This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried o...This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried on the test in transmission field. This paper introduces in detail the structure and characteristic of DSP system, and gives a design scheme of Doubly Fed Speed Control System of motor based on this chip.展开更多
During flight operations,quadrotor UAVs are susceptible to interference from environmental factors such as wind gusts,battery depletion,and obstacles,which may compromise flight stability.This study proposes a fuzzy a...During flight operations,quadrotor UAVs are susceptible to interference from environmental factors such as wind gusts,battery depletion,and obstacles,which may compromise flight stability.This study proposes a fuzzy adaptive PID controller(Fuzzy PID)combining PID control with fuzzy logic to achieve self-adaptive adjustment of PID parameters in UAV flight control systems,thereby enhancing system robustness.A quadrotor UAV control model was developed in Simulink,and a Fuzzy PID control system was constructed by integrating fuzzy control logic for simulation and experimental validation.Test results demonstrate that UAVs governed by Fuzzy PID control exhibit faster regulation speed and improved stability when subjected to disturbances.展开更多
A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis ...A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis and experiment results show the frequency difference method is a ideal power saving speed regulation method for the dou- ble inverter and motor system.The experiment system is simply structured,convenient to operate and provides a new way of character testing for frequency conversion speed regulation.展开更多
Main Exhauster is one of the main equipment of sintering production. It needs to consume a lot of electricity. Therefore, the system＇ s reconstruction for energy-saving will effectively reduce electricity for the pro...Main Exhauster is one of the main equipment of sintering production. It needs to consume a lot of electricity. Therefore, the system＇ s reconstruction for energy-saving will effectively reduce electricity for the production. The paper takes an iron and steel enterprise that had successfully transformed the synchronous motors of main exhauster of sintering as an example, which describes the application of high-voltage variable frequency speed regulation system in main exhauster of Sintering, so as to provide a reference for other iron and steel enterprises.展开更多
The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg rats.However,the current stimulation techniques cannot realize the graded control of the speed.In this s...The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg rats.However,the current stimulation techniques cannot realize the graded control of the speed.In this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration period.We concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg rats.Whereas the amplitude of stimulation was found to affect the response time exhibited by the cyborg rats.Our study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.展开更多
During the operation of the speed governing system of the power plant, the deterioration of fire-resistant oil is common, which will not only affect the normal operation of the whole system, but also lead to the waste...During the operation of the speed governing system of the power plant, the deterioration of fire-resistant oil is common, which will not only affect the normal operation of the whole system, but also lead to the waste of resources. Therefore, in actual work, relevant technicians need to strengthen the in-depth analysis of the causes of this problem, implement the working principle of adjusting measures to local conditions, and select the correct protective measures to ensure the normal use of the speed governing system of the power plant. Reduce the occurrence of various contradictions and establish more scientific maintenance measures through experience summary to improve the production effect of power plants and promote the stable development of power plants in China.展开更多
The Hydro-Viscous Drive(HVD)speed regulating system finds extensive application in air transport transmission systems to regulate the stepless speed or conduct overload protection.However,its intrinsic hysteretic beha...The Hydro-Viscous Drive(HVD)speed regulating system finds extensive application in air transport transmission systems to regulate the stepless speed or conduct overload protection.However,its intrinsic hysteretic behaviors,such as the asymmetric hysteretic and dead zone,could introduce inaccuracy and delay in control applications,posing challenges to system regulation.This paper investigates a Nonlinear Hysteresis Compensation Control(NHCC)that consists of two parts to control the HVD output speed by operating the valve under different engine operating conditions.In the first part,the Inverse Hysteresis Compensator(IHC)based on major loop data is introduced for the asymmetric hysteresis characterization and compensation of the HVD speed control system of the power generation and distribution,which aims to reduce the hysteresis and dead zone effect and expand the effective input range.In the second part,the Active Disturbance Rejection Controller(ADRC)is employed to mitigate the hysteresis effects of the compensated system and remove the steady-state error,which allows real-time compensation of the estimated perturbations as state feedback to achieve the required performance.An experimental laboratory station has been fabricated to evaluate the proposed method.The test results show that the NHCC method can regulate the fan speed to the desired value(45 r/min at steady state)and broaden the effective input range to the full range under different engine conditions.Besides,the proposed control method can reduce the non-linearity of the input and output curves(from 18%to 4%)and compensate for the asymmetric hysteresis(from 38%to 5%).展开更多
The blisk is a core component of an aero-engine,and electrochemical machining(ECM)is the primary method for its manufacture.Among several ECM methods for blisks,multi-tool synchronous machining is the most efficient a...The blisk is a core component of an aero-engine,and electrochemical machining(ECM)is the primary method for its manufacture.Among several ECM methods for blisks,multi-tool synchronous machining is the most efficient and advantageous for machining channels.The allowance distribution of the blank after blisk channel machining directly influences the blade profile accuracy.This paper proposes a trajectory control strategy to homogenize the allowance distribution of the blisk channel in multi-tool ECM.The strategy includes the design of the three-dimensional space motion of the tool and blisk,as well as the regulated feed speed.The structural characteristics of the blisk channel and the principle of ECM allow for designing and optimizing the multidimensional trajectory.The electric field simulations elucidate the influence law of the three-axis feed speed on the side gap.An algorithm is adopted to iteratively optimize the speeds for different positions to realize multi-dimensional motion control and allowance homogenization.The proposed trajectory control strategy is applied to ECM experiments for the blisk channel.Compared with the constant feed speed mode,the regulated speed strategy reduces the maximum allowance difference between the convex(CV)profiles by 36.18%and that between the concave(CC)profiles by 37.73%.Subsequently,the one-time ECM of eight blisk channels was successfully realized.The average time for a single channel was 12.5 min,significantly improving the machining efficiency.In conclusion,the proposed method is effective and can be extended for synchronously machining various blisk types with twisted channels.展开更多
This paper investigates the issue of load disturbances in DC motor speed regulation systems.In response to the limited disturbance rejection capability of traditional PID controllers,a PID controller with feedforward ...This paper investigates the issue of load disturbances in DC motor speed regulation systems.In response to the limited disturbance rejection capability of traditional PID controllers,a PID controller with feedforward compensation is designed.The study first analyzes the dynamic impact mechanism of sudden load changes on motor speed,and then achieves precise control of the DC motor using PWM technology.Through comparative analysis of simulation and experimental results,the proposed feedforward-compens ated PID control demonstrates significant improvements in dynamic response speed,overshoot,and steady-state accuracy compared to traditional PID control.The findings indicate that the proposed control strategy effectively supp resses load disturbances,e nhances system stability and robustness,and offers valuable insights for practical engineering applications.展开更多
Steering control strategy for high-speed tracked vehicle with hydrostatic drive is designed based on analyzing the fundamental steering theories of the hydrostatic drive tracked vehicle. The strategy is completed by t...Steering control strategy for high-speed tracked vehicle with hydrostatic drive is designed based on analyzing the fundamental steering theories of the hydrostatic drive tracked vehicle. The strategy is completed by the cooperation between integrated steering control unit and pump ＆ motor displacement controller. The steering simulation is conducted by using Simulink of Matlab. It is indicated that this steering control strategy can reduce the average vehicle speed automatically to achieve the driver＇s expected steering radius exactly in the case of en- suring not exceeding the system pressure threshold and no sideslip.展开更多
Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the...Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the requirements of fast response,high accuracy and good robustness.In order to improve the performance of DTP-PMSM speed regulation system,a control strategy of PI controller based on genetic algorithm is proposed.Firstly,the basic mathematical model of DTP-PMSM is established,and the PI parameters of DTP-PMSM speed regulation system are optimized by genetic algorithm,and the modeling and simulation experiments of DTP-PMSM control system are carried out by MATLAB/SIMULINK.The simulation results show that,compared with the traditional PI control,the proposed algorithm significantly improves the performance of the control system,and the speed output overshoot of the GA-PI speed control system is smaller.The anti-interference ability is stronger,and the torque and double three-phase current output fluctuations are smaller.展开更多
The speed regulation problem with only speed measurement is investigated in this paper for a permanent magnet direct current(DC)motor driven by a buck converter.By lumping all unknown matched/unmatched disturbances an...The speed regulation problem with only speed measurement is investigated in this paper for a permanent magnet direct current(DC)motor driven by a buck converter.By lumping all unknown matched/unmatched disturbances and uncertainties together,the traditional active disturbance rejection control(ADRC)approach provides an intuitive solution for the problem under consideration.However,for such a higher-order disturbed system,the increase of poles for the extended state observer(ESO)therein will lead to drastically growth of observer gains,which causes severe noise amplification.This paper aims to propose a new model-based disturbance rejection controller for the converter-driven DC motor system using output-feedback.Instead of estimating lumped disturbances directly,a new observer is constructed to estimate the desired steady state of control signal as well as errors between the real states and their desired steady-state responses.Thereafter,a controller with only speed measurement is proposed by utilizing the estimates.The performance of the proposed method is tested through experiments on dSPACE.It is further shown via numerical calculations and experimental results that the poles of the observer within the proposed control approach can be largely increased without significantly increasing magnitude of the observer gains.展开更多
This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed control...This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed controller is designed to include an active damping term that regulates the motor speed in accordance with the first-order low-pass filter dynamics through the pole-zero cancellation.Meanwhile,the angular acceleration and its reference are obtained from simple first-order estimators using only the speed information.The effectiveness is experimentally verified using hardware comprising the QUBEServo2,myRIO-1900,and LabVIEW.展开更多
This study aims to develop an accurate calculation model of transmission torque and load-bearing capacity for hydro-viscous clutches(HVC)used in high-power vehicles,which is important to investigate the step-less spee...This study aims to develop an accurate calculation model of transmission torque and load-bearing capacity for hydro-viscous clutches(HVC)used in high-power vehicles,which is important to investigate the step-less speed regulation characteristics in a fan drive system.However,most of the existing models ignore the distribution differences of groove area along the radial direction,which may lead to significant deviations in calculating the mechanical property of friction pairs related to operating conditions and the engagement process.To fill this gap,a new calculation model for bearing capacity and frictional torque of friction pairs with different oil grooves is proposed,in which the traditional fixed contact area ratio coefficient for oil groove measurement is replaced by a more precise discrete micro-ring area ratio(DMAR)integration method.Then,a 32-degree-of-freedoms dynamic model of HVC at a fan drive system is established for the prediction of dynamic responses during speed regulation.Results show that friction pairs with different oil grooves have a direct influence on frictional torque and bearing capacity through the change of DMAR along the radial direction.The friction pairs with different groove structures have oscillation phenomena at the engagement steady-state boundary.Furthermore,a step-less speed regulation experimental setup is established to verify the correctness of the proposed model.It is demonstrated that the axial engagement force and the speed regulation curve predicted by the proposed method are in good agreement with the experimental data.The results could effectively predict the engagement dynamic characteristics.The numerical relationship among the structure parameters,the mechanical properties of friction pairs,and the speed regulation characteristics of the system are established through the proposed model,which lays a theoretical foundation for the structure design of friction plates and optimization of step-less speed regulation performance.展开更多
With the continuous development of peoples life, the requirements for the quality of life are getting better and better, especially for the living environment and green development. In order to protect the environment...With the continuous development of peoples life, the requirements for the quality of life are getting better and better, especially for the living environment and green development. In order to protect the environment and take the path of green development, it is necessary to change the source of energy. Hydropower is favored by people with its advantages of environmental protection. The wide application of hydropower also promotes the increasing number of hydropower stations. The number of hydropower stations in China is large, but the service time of hydropower stations is relatively short, and there are still some problems in many aspects. Governor is an indispensable device for hydropower generation, which plays an irreplaceable role in hydropower generation. Once there is a problem with the governor of hydropower station, it will affect the whole power station. In order to reduce the impact of the governor failure of hydropower station, we must analyze the common faults of the governor of hydropower station, and prepare the corresponding maintenance plan for these common faults, which can be repaired quickly in case of failure, so as to minimize the impact on the hydropower station as far as possible. This paper briefly analyzes the common faults and maintenance methods of the governor of hydropower station.展开更多
The principle and structure of hydro-viscous drive(HVD) set is introduced. Through theoretical analysis of the HVD set start-up steadiness, the conclusions were obtained that the non-linearity of the pressure performa...The principle and structure of hydro-viscous drive(HVD) set is introduced. Through theoretical analysis of the HVD set start-up steadiness, the conclusions were obtained that the non-linearity of the pressure performance curve and dynamic pressure instability of the pilot-operated electro-hydraulic pressure relief valve, which is used for the HVD speed regulating purpose and usually works within micro flow-rate and low oil pressure state, are the main causes of the poor start-up steadiness. So a special speed regulating valve for HVD set is developed, with which the start-up steadiness of HVD set is much improved.展开更多
This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally s...This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally spaced circularly which are joined by six connecting boards to form a whole closed hexagonal body to clasp a cable. The whole design is entirely modular to enable to assenably the robot on-siteeasy eaoily. To analyze the static features of the robot, a mathematical model of climbing is deduced. Furthermore, taking a cable with a diameter of 80mm as an example, we calculate the design parameters of the robot. For safly landing in the case of electrical accident, a centrifugal speed regulator is proposed and applied to consume useless energy generated when the robot is slipping down along the cables. A simplified mathematical model of the landing mechanism is deduced. Finally, several experiments on the climbing mechanism demonstrate that the robot can carry payloads less than 2.2kg to climb up a cable with diameters varying from 65mm to 205mm.展开更多
Due to the working environment and process requirements of 100 ton crane of iron casting machine, the high failure rate of 100 tons crane of iron casting machine directly leads to the high maintenance cost of 100 tons...Due to the working environment and process requirements of 100 ton crane of iron casting machine, the high failure rate of 100 tons crane of iron casting machine directly leads to the high maintenance cost of 100 tons crane, the large workload of maintenance workers and the working efficiency of iron casting machine is low which restricts the production of iron casting machine. For many years, all kinds of day car owners hook motor speed regulation has been using the motor rotor series resistance speed regulation method, the differential power in the form of heating consumption of resistance. The application of voltage regulating and speed regulating controller in one hundred ton crane fundamentally solves this problem. This paper mainly introduces the working principle, use and maintenance of voltage regulating and speed regulating controller展开更多
In the process of oilfield water injection volume of injection allocation often appear with the pump displacement situation does not match, the widespread adoption of stator frequency technology allows the pump displa...In the process of oilfield water injection volume of injection allocation often appear with the pump displacement situation does not match, the widespread adoption of stator frequency technology allows the pump displacement and volume of injection allocation phase matching. But the technology in pump class load application speed range is limited, there is still a reflux valve control blind area,＂ turn off undead＂ problem. ＂ One-for-several＂ rotor frequency Technique in water injection station application, solved the control blind area problem, the full realization of the variable frequency close return voltage injection, at the same time, the successful implementation of the slip power efficient feedback. Stable water injection pressure of the system, and the electric energy is saved, satisfy the oilfield high efficiency, fine water needs, has a high application value.展开更多
Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also benefic...Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.展开更多
文摘This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried on the test in transmission field. This paper introduces in detail the structure and characteristic of DSP system, and gives a design scheme of Doubly Fed Speed Control System of motor based on this chip.
基金The 2023 Scientific and Technological Project in Henan Province of China(232102220098)。
文摘During flight operations,quadrotor UAVs are susceptible to interference from environmental factors such as wind gusts,battery depletion,and obstacles,which may compromise flight stability.This study proposes a fuzzy adaptive PID controller(Fuzzy PID)combining PID control with fuzzy logic to achieve self-adaptive adjustment of PID parameters in UAV flight control systems,thereby enhancing system robustness.A quadrotor UAV control model was developed in Simulink,and a Fuzzy PID control system was constructed by integrating fuzzy control logic for simulation and experimental validation.Test results demonstrate that UAVs governed by Fuzzy PID control exhibit faster regulation speed and improved stability when subjected to disturbances.
文摘A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis and experiment results show the frequency difference method is a ideal power saving speed regulation method for the dou- ble inverter and motor system.The experiment system is simply structured,convenient to operate and provides a new way of character testing for frequency conversion speed regulation.
文摘Main Exhauster is one of the main equipment of sintering production. It needs to consume a lot of electricity. Therefore, the system＇ s reconstruction for energy-saving will effectively reduce electricity for the production. The paper takes an iron and steel enterprise that had successfully transformed the synchronous motors of main exhauster of sintering as an example, which describes the application of high-voltage variable frequency speed regulation system in main exhauster of Sintering, so as to provide a reference for other iron and steel enterprises.
基金the National Key R&D Program of China(2020YFB1313501)Zhejiang Provincial Natural Science Foundation(LZ24F020003)+2 种基金National Natural Science Foundation of China(T2293723)the Key R&D program of Zhejiang Province(2021C03003)the Fundamental Research Funds for the Central Universities(No.226-2022-00051).
文摘The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg rats.However,the current stimulation techniques cannot realize the graded control of the speed.In this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration period.We concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg rats.Whereas the amplitude of stimulation was found to affect the response time exhibited by the cyborg rats.Our study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.
文摘During the operation of the speed governing system of the power plant, the deterioration of fire-resistant oil is common, which will not only affect the normal operation of the whole system, but also lead to the waste of resources. Therefore, in actual work, relevant technicians need to strengthen the in-depth analysis of the causes of this problem, implement the working principle of adjusting measures to local conditions, and select the correct protective measures to ensure the normal use of the speed governing system of the power plant. Reduce the occurrence of various contradictions and establish more scientific maintenance measures through experience summary to improve the production effect of power plants and promote the stable development of power plants in China.
文摘The Hydro-Viscous Drive(HVD)speed regulating system finds extensive application in air transport transmission systems to regulate the stepless speed or conduct overload protection.However,its intrinsic hysteretic behaviors,such as the asymmetric hysteretic and dead zone,could introduce inaccuracy and delay in control applications,posing challenges to system regulation.This paper investigates a Nonlinear Hysteresis Compensation Control(NHCC)that consists of two parts to control the HVD output speed by operating the valve under different engine operating conditions.In the first part,the Inverse Hysteresis Compensator(IHC)based on major loop data is introduced for the asymmetric hysteresis characterization and compensation of the HVD speed control system of the power generation and distribution,which aims to reduce the hysteresis and dead zone effect and expand the effective input range.In the second part,the Active Disturbance Rejection Controller(ADRC)is employed to mitigate the hysteresis effects of the compensated system and remove the steady-state error,which allows real-time compensation of the estimated perturbations as state feedback to achieve the required performance.An experimental laboratory station has been fabricated to evaluate the proposed method.The test results show that the NHCC method can regulate the fan speed to the desired value(45 r/min at steady state)and broaden the effective input range to the full range under different engine conditions.Besides,the proposed control method can reduce the non-linearity of the input and output curves(from 18%to 4%)and compensate for the asymmetric hysteresis(from 38%to 5%).
基金co-supported by the National Natural Science Foundation of China(No.52075253)the National Natural Science Foundation of China for Creative Research Groups(No.51921003)the Industrial Technology Development Program(No.JCKY2021605B026)。
文摘The blisk is a core component of an aero-engine,and electrochemical machining(ECM)is the primary method for its manufacture.Among several ECM methods for blisks,multi-tool synchronous machining is the most efficient and advantageous for machining channels.The allowance distribution of the blank after blisk channel machining directly influences the blade profile accuracy.This paper proposes a trajectory control strategy to homogenize the allowance distribution of the blisk channel in multi-tool ECM.The strategy includes the design of the three-dimensional space motion of the tool and blisk,as well as the regulated feed speed.The structural characteristics of the blisk channel and the principle of ECM allow for designing and optimizing the multidimensional trajectory.The electric field simulations elucidate the influence law of the three-axis feed speed on the side gap.An algorithm is adopted to iteratively optimize the speeds for different positions to realize multi-dimensional motion control and allowance homogenization.The proposed trajectory control strategy is applied to ECM experiments for the blisk channel.Compared with the constant feed speed mode,the regulated speed strategy reduces the maximum allowance difference between the convex(CV)profiles by 36.18%and that between the concave(CC)profiles by 37.73%.Subsequently,the one-time ECM of eight blisk channels was successfully realized.The average time for a single channel was 12.5 min,significantly improving the machining efficiency.In conclusion,the proposed method is effective and can be extended for synchronously machining various blisk types with twisted channels.
文摘This paper investigates the issue of load disturbances in DC motor speed regulation systems.In response to the limited disturbance rejection capability of traditional PID controllers,a PID controller with feedforward compensation is designed.The study first analyzes the dynamic impact mechanism of sudden load changes on motor speed,and then achieves precise control of the DC motor using PWM technology.Through comparative analysis of simulation and experimental results,the proposed feedforward-compens ated PID control demonstrates significant improvements in dynamic response speed,overshoot,and steady-state accuracy compared to traditional PID control.The findings indicate that the proposed control strategy effectively supp resses load disturbances,e nhances system stability and robustness,and offers valuable insights for practical engineering applications.
基金Sponsored by the Ministerial Level Advanced Research Foundation(2630103)
文摘Steering control strategy for high-speed tracked vehicle with hydrostatic drive is designed based on analyzing the fundamental steering theories of the hydrostatic drive tracked vehicle. The strategy is completed by the cooperation between integrated steering control unit and pump ＆ motor displacement controller. The steering simulation is conducted by using Simulink of Matlab. It is indicated that this steering control strategy can reduce the average vehicle speed automatically to achieve the driver＇s expected steering radius exactly in the case of en- suring not exceeding the system pressure threshold and no sideslip.
基金supported in part by the Liaoning Provincial Department of Education Key Research Project under JYT2020160by the Liaoning Provincial Department of Education General Project under LJKZ0224。
文摘Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the requirements of fast response,high accuracy and good robustness.In order to improve the performance of DTP-PMSM speed regulation system,a control strategy of PI controller based on genetic algorithm is proposed.Firstly,the basic mathematical model of DTP-PMSM is established,and the PI parameters of DTP-PMSM speed regulation system are optimized by genetic algorithm,and the modeling and simulation experiments of DTP-PMSM control system are carried out by MATLAB/SIMULINK.The simulation results show that,compared with the traditional PI control,the proposed algorithm significantly improves the performance of the control system,and the speed output overshoot of the GA-PI speed control system is smaller.The anti-interference ability is stronger,and the torque and double three-phase current output fluctuations are smaller.
基金supported in part by the Natural Science Foundation of China(61973080,61973081)by the Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration(201928069002)the Key R&D Plan of Jiangsu Province(BE2020082-4)。
文摘The speed regulation problem with only speed measurement is investigated in this paper for a permanent magnet direct current(DC)motor driven by a buck converter.By lumping all unknown matched/unmatched disturbances and uncertainties together,the traditional active disturbance rejection control(ADRC)approach provides an intuitive solution for the problem under consideration.However,for such a higher-order disturbed system,the increase of poles for the extended state observer(ESO)therein will lead to drastically growth of observer gains,which causes severe noise amplification.This paper aims to propose a new model-based disturbance rejection controller for the converter-driven DC motor system using output-feedback.Instead of estimating lumped disturbances directly,a new observer is constructed to estimate the desired steady state of control signal as well as errors between the real states and their desired steady-state responses.Thereafter,a controller with only speed measurement is proposed by utilizing the estimates.The performance of the proposed method is tested through experiments on dSPACE.It is further shown via numerical calculations and experimental results that the poles of the observer within the proposed control approach can be largely increased without significantly increasing magnitude of the observer gains.
基金supported in part by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(2020M3H4A3106326)supported in part by the NRF grant funded by the Korea government(Ministry of Science and ICT)(NRF-2020R1A2C1005449)。
文摘This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed controller is designed to include an active damping term that regulates the motor speed in accordance with the first-order low-pass filter dynamics through the pole-zero cancellation.Meanwhile,the angular acceleration and its reference are obtained from simple first-order estimators using only the speed information.The effectiveness is experimentally verified using hardware comprising the QUBEServo2,myRIO-1900,and LabVIEW.
基金Supported by the National Natural Science Foundation of China(Grant Nos.52475089,52035002)National Key Research and Development Program of China(Grant No.2021YFB2011400)the Chongqing Natural Science Foundation(Grant No.CSTB2022NSCQ-MSX1243).
文摘This study aims to develop an accurate calculation model of transmission torque and load-bearing capacity for hydro-viscous clutches(HVC)used in high-power vehicles,which is important to investigate the step-less speed regulation characteristics in a fan drive system.However,most of the existing models ignore the distribution differences of groove area along the radial direction,which may lead to significant deviations in calculating the mechanical property of friction pairs related to operating conditions and the engagement process.To fill this gap,a new calculation model for bearing capacity and frictional torque of friction pairs with different oil grooves is proposed,in which the traditional fixed contact area ratio coefficient for oil groove measurement is replaced by a more precise discrete micro-ring area ratio(DMAR)integration method.Then,a 32-degree-of-freedoms dynamic model of HVC at a fan drive system is established for the prediction of dynamic responses during speed regulation.Results show that friction pairs with different oil grooves have a direct influence on frictional torque and bearing capacity through the change of DMAR along the radial direction.The friction pairs with different groove structures have oscillation phenomena at the engagement steady-state boundary.Furthermore,a step-less speed regulation experimental setup is established to verify the correctness of the proposed model.It is demonstrated that the axial engagement force and the speed regulation curve predicted by the proposed method are in good agreement with the experimental data.The results could effectively predict the engagement dynamic characteristics.The numerical relationship among the structure parameters,the mechanical properties of friction pairs,and the speed regulation characteristics of the system are established through the proposed model,which lays a theoretical foundation for the structure design of friction plates and optimization of step-less speed regulation performance.
文摘With the continuous development of peoples life, the requirements for the quality of life are getting better and better, especially for the living environment and green development. In order to protect the environment and take the path of green development, it is necessary to change the source of energy. Hydropower is favored by people with its advantages of environmental protection. The wide application of hydropower also promotes the increasing number of hydropower stations. The number of hydropower stations in China is large, but the service time of hydropower stations is relatively short, and there are still some problems in many aspects. Governor is an indispensable device for hydropower generation, which plays an irreplaceable role in hydropower generation. Once there is a problem with the governor of hydropower station, it will affect the whole power station. In order to reduce the impact of the governor failure of hydropower station, we must analyze the common faults of the governor of hydropower station, and prepare the corresponding maintenance plan for these common faults, which can be repaired quickly in case of failure, so as to minimize the impact on the hydropower station as far as possible. This paper briefly analyzes the common faults and maintenance methods of the governor of hydropower station.
文摘The principle and structure of hydro-viscous drive(HVD) set is introduced. Through theoretical analysis of the HVD set start-up steadiness, the conclusions were obtained that the non-linearity of the pressure performance curve and dynamic pressure instability of the pilot-operated electro-hydraulic pressure relief valve, which is used for the HVD speed regulating purpose and usually works within micro flow-rate and low oil pressure state, are the main causes of the poor start-up steadiness. So a special speed regulating valve for HVD set is developed, with which the start-up steadiness of HVD set is much improved.
基金Supported by the National High Technology Research and Development Programme of China （No. 2006AA04Z234） and the China Postdoctoral Science Foundation （ No. 20090461051 ）
文摘This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally spaced circularly which are joined by six connecting boards to form a whole closed hexagonal body to clasp a cable. The whole design is entirely modular to enable to assenably the robot on-siteeasy eaoily. To analyze the static features of the robot, a mathematical model of climbing is deduced. Furthermore, taking a cable with a diameter of 80mm as an example, we calculate the design parameters of the robot. For safly landing in the case of electrical accident, a centrifugal speed regulator is proposed and applied to consume useless energy generated when the robot is slipping down along the cables. A simplified mathematical model of the landing mechanism is deduced. Finally, several experiments on the climbing mechanism demonstrate that the robot can carry payloads less than 2.2kg to climb up a cable with diameters varying from 65mm to 205mm.
文摘Due to the working environment and process requirements of 100 ton crane of iron casting machine, the high failure rate of 100 tons crane of iron casting machine directly leads to the high maintenance cost of 100 tons crane, the large workload of maintenance workers and the working efficiency of iron casting machine is low which restricts the production of iron casting machine. For many years, all kinds of day car owners hook motor speed regulation has been using the motor rotor series resistance speed regulation method, the differential power in the form of heating consumption of resistance. The application of voltage regulating and speed regulating controller in one hundred ton crane fundamentally solves this problem. This paper mainly introduces the working principle, use and maintenance of voltage regulating and speed regulating controller
文摘In the process of oilfield water injection volume of injection allocation often appear with the pump displacement situation does not match, the widespread adoption of stator frequency technology allows the pump displacement and volume of injection allocation phase matching. But the technology in pump class load application speed range is limited, there is still a reflux valve control blind area,＂ turn off undead＂ problem. ＂ One-for-several＂ rotor frequency Technique in water injection station application, solved the control blind area problem, the full realization of the variable frequency close return voltage injection, at the same time, the successful implementation of the slip power efficient feedback. Stable water injection pressure of the system, and the electric energy is saved, satisfy the oilfield high efficiency, fine water needs, has a high application value.
文摘Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.
