This paper presents the construction of an active suspension control of a one-wheel car model using fuzzy reasoning and a disturbance observer. The one-wheel car model to be treated here can be approximately described...This paper presents the construction of an active suspension control of a one-wheel car model using fuzzy reasoning and a disturbance observer. The one-wheel car model to be treated here can be approximately described as a nonlinear two degrees of freedom system subject to excitation from a road profile. The active control is designed as the fuzzy control inferred by using single input rule modules fuzzy reasoning, and the active control force is released by actuating a pneumatic actuator. The excitation from the road profile is estimated by using a disturbance observer, and the estimate is denoted as one of the variables in the precondition part of the fuzzy control rules. A compensator is inserted to counter the performance degradation due to the delay of the pneumatic actuator. The experimental result indicates that the proposed active suspension system improves much the vibration suppression of the car model. Key words One-wheel car model - Active suspension system - Single input rule modules fuzzy reasoning - Pneumatic actuator - Disturbance observer Document code A CLC number TH16展开更多
Wind is one kind of clean and free renewable energy sources. Wind speed plays a pivotal role in the wind power output. However, due to the random and unstable nature of the wind, accurate prediction of wind speed is a...Wind is one kind of clean and free renewable energy sources. Wind speed plays a pivotal role in the wind power output. However, due to the random and unstable nature of the wind, accurate prediction of wind speed is a particularly challenging task. This paper presents a novel neural fuzzy method for the hourly wind speed prediction. Firstly, a neural structure is proposed for the functional-type single-input-rule-modules(FSIRMs) connected fuzzy inference system(FIS) to combine the merits of both the FSIRMs connected FIS and the neural network. Then, in order to achieve both the smallest training errors and the smallest parameters, a least square method based parameter learning algorithm is presented for the proposed FSIRMs connected neural fuzzy system(FSIRMNFS). Further,the proposed FSIRMNFS and its parameter learning algorithm are applied to the hourly wind speed prediction. Experiments and comparisons are also made to show the effectiveness and advantages of the proposed approach. Experimental results verified that our study has presented an effective approach for the hourly wind speed prediction. The proposed approach can also be used for the prediction of wind direction, wind power and some other prediction applications in the research field of renewable energy.展开更多
A single column model (SCM) is constructed by extracting the physical subroutines from the NCAR Community Climate Model version 1 (CCM1).Simulated data are generated by CCM1 and used to validate the SCM and to study t...A single column model (SCM) is constructed by extracting the physical subroutines from the NCAR Community Climate Model version 1 (CCM1).Simulated data are generated by CCM1 and used to validate the SCM and to study the sensitivity of the SCM to errors in its input data.It is found that the SCM temperature predictions are moderately sensitive to errors in the input horizontal temperature flux convergence and moisture flux convergence.Two types of error are concerned in this study,random errors due to insufficient data resolution,and errors due to insufficient data area coverage.While the first type of error can be reduced by filtering and/or increasing the data resolution,it is shown that the second type of error can be reduced by enlarging the data area coverage and using a suitable method to compute the input flux convergence terms.展开更多
An efficient method for blind classification of space time block codes （STBCs） based on fourth-order cumulants is proposed for a single receiver antenna. This paper presents a model of received STBCs signals in mult...An efficient method for blind classification of space time block codes （STBCs） based on fourth-order cumulants is proposed for a single receiver antenna. This paper presents a model of received STBCs signals in multiple input single output （MISO） communication systems and applies the characteristics of coding matrices to derive analytical expressions for the fourth-order cumu- lants to be used as the basis of an algorithm. The fourth-order cumulants at various delay vectors present non-null values that depend on the transmitted STBCs. Tests of nullity are accomplished by hypothesis testing. The proposed algorithm avoids the need for a priori information of modulation scheme, channel coefficients, and noise power. Consequently, it is well suited for non-cooperative scenarios. Simulations show that this method performs well even at low signal-to-noise ratios （SNRs）.展开更多
Inter-area low frequency oscillation in power system is one of the major problems for bulk power transmission through weak tie lines.Use of wide-area signal is more effective than the local area signal in damping out ...Inter-area low frequency oscillation in power system is one of the major problems for bulk power transmission through weak tie lines.Use of wide-area signal is more effective than the local area signal in damping out the inter-area oscillations.Wide area measurement system(WAMS)is convenient to transmit the wide area signal through the communication channel to the remote location.Communication failure is one of the disastrous phenomena in a communication channel.In this paper,a dual input single output(DISO)Hm controller is designed to build the control resiliency by employing two highest observability ranking wide area signals with respect to the critical damping inter-area mode.The proposed controller can provide sufficient damping to the system and also the system remains stabilized if one of the wide-area signals is lost.The time delay is an unwanted phenomenon that degrades the performance of the controllers.The unified Smith predictor approach is used to design a Hm controller to handle the time delay.Kundur's two-area and IEEE-39 bus test systems are considered to verify the effectiveness of the proposed controller.From the simulation results,it is verified that,the proposed controller provides excellent damping performance at normal communication and improves the controller resiliency to counteract the communication failure.展开更多
The feedback delay can severely affect the quality of the channel state information at the transmitter(CSIT)which is fed back from the receiver.The outdated CSIT will cause large performance loss in the transmit beamf...The feedback delay can severely affect the quality of the channel state information at the transmitter(CSIT)which is fed back from the receiver.The outdated CSIT will cause large performance loss in the transmit beamforming systems.The effect of variable feedback delay on the capacity of transmit beamforming systems over Rayleigh fading channels is studied.First,the case of fixed feedback delay is considered and a closed-form expression of system capacity is derived.Based on the results of fixed delay,the delay following certain distributions in variable delay case is assumed and the closed-form expressions of capacities are derived.The closed-form expressions show that the capacity is significantly affected by the statistical characteristics of the feedback delay.The obtained results provide an analytical insight into the effects caused by variable delay on the system capacity.展开更多
An on-board charger for efficiently charging multiple battery-operated electric vehicles(EVs)is introduced.It has evolved as a single-input dual-output(SIDO)integrated boost-single ended primary inductor converter(SEP...An on-board charger for efficiently charging multiple battery-operated electric vehicles(EVs)is introduced.It has evolved as a single-input dual-output(SIDO)integrated boost-single ended primary inductor converter(SEPIC)fly-back converter,offering cost-effectiveness,reliability,and higher efficiency compared to conventional chargers with equivalent specifications.The proposed system includes an additional regulated output terminal,in addition to an existing terminal for charging the EV battery of a 4-wheeler,which can be used to charge another EV battery,preferably a 2-wheeler.With the aid of control techniques,unity power factor operations are obtained during constant-voltage(CV)/constant-current(CC)charging for the grid-to-vehicle(G2V)operating mode.Using mathematical modelling analysis,the proposed system is developed in a Matlab/Simulink environment,and the results are validated in a real-time simulator using dSPACE-1104.The proposed system is employed for charging the batteries of two EVs with capacities of 400 V,40 A·h and 48 V,52 A·h for the 4-wheeler and 2-wheeler,respectively.Its performance is investigated under different operating modes and over a wide range of supply voltage variations to ensure safe and reliable operation of the charger.展开更多
文摘This paper presents the construction of an active suspension control of a one-wheel car model using fuzzy reasoning and a disturbance observer. The one-wheel car model to be treated here can be approximately described as a nonlinear two degrees of freedom system subject to excitation from a road profile. The active control is designed as the fuzzy control inferred by using single input rule modules fuzzy reasoning, and the active control force is released by actuating a pneumatic actuator. The excitation from the road profile is estimated by using a disturbance observer, and the estimate is denoted as one of the variables in the precondition part of the fuzzy control rules. A compensator is inserted to counter the performance degradation due to the delay of the pneumatic actuator. The experimental result indicates that the proposed active suspension system improves much the vibration suppression of the car model. Key words One-wheel car model - Active suspension system - Single input rule modules fuzzy reasoning - Pneumatic actuator - Disturbance observer Document code A CLC number TH16
基金supported by the National Natural Science Foundation of China(61473176,61402260,61573225)the Natural Science Foundation of Shandong Province for Outstanding Young Talents in Provincial Universities(ZR2015JL021,ZR2015JL003)the Open Program from the State Key Laboratory of Management and Control for Complex Systems(20140102)
文摘Wind is one kind of clean and free renewable energy sources. Wind speed plays a pivotal role in the wind power output. However, due to the random and unstable nature of the wind, accurate prediction of wind speed is a particularly challenging task. This paper presents a novel neural fuzzy method for the hourly wind speed prediction. Firstly, a neural structure is proposed for the functional-type single-input-rule-modules(FSIRMs) connected fuzzy inference system(FIS) to combine the merits of both the FSIRMs connected FIS and the neural network. Then, in order to achieve both the smallest training errors and the smallest parameters, a least square method based parameter learning algorithm is presented for the proposed FSIRMs connected neural fuzzy system(FSIRMNFS). Further,the proposed FSIRMNFS and its parameter learning algorithm are applied to the hourly wind speed prediction. Experiments and comparisons are also made to show the effectiveness and advantages of the proposed approach. Experimental results verified that our study has presented an effective approach for the hourly wind speed prediction. The proposed approach can also be used for the prediction of wind direction, wind power and some other prediction applications in the research field of renewable energy.
文摘A single column model (SCM) is constructed by extracting the physical subroutines from the NCAR Community Climate Model version 1 (CCM1).Simulated data are generated by CCM1 and used to validate the SCM and to study the sensitivity of the SCM to errors in its input data.It is found that the SCM temperature predictions are moderately sensitive to errors in the input horizontal temperature flux convergence and moisture flux convergence.Two types of error are concerned in this study,random errors due to insufficient data resolution,and errors due to insufficient data area coverage.While the first type of error can be reduced by filtering and/or increasing the data resolution,it is shown that the second type of error can be reduced by enlarging the data area coverage and using a suitable method to compute the input flux convergence terms.
基金co-supported by the Taishan Scholar Special Foundation of China(No.ts201511020)
文摘An efficient method for blind classification of space time block codes （STBCs） based on fourth-order cumulants is proposed for a single receiver antenna. This paper presents a model of received STBCs signals in multiple input single output （MISO） communication systems and applies the characteristics of coding matrices to derive analytical expressions for the fourth-order cumu- lants to be used as the basis of an algorithm. The fourth-order cumulants at various delay vectors present non-null values that depend on the transmitted STBCs. Tests of nullity are accomplished by hypothesis testing. The proposed algorithm avoids the need for a priori information of modulation scheme, channel coefficients, and noise power. Consequently, it is well suited for non-cooperative scenarios. Simulations show that this method performs well even at low signal-to-noise ratios （SNRs）.
基金support by the Central Power Research Institute,India(CPRI/RD/RSOP/GRANT/2015)
文摘Inter-area low frequency oscillation in power system is one of the major problems for bulk power transmission through weak tie lines.Use of wide-area signal is more effective than the local area signal in damping out the inter-area oscillations.Wide area measurement system(WAMS)is convenient to transmit the wide area signal through the communication channel to the remote location.Communication failure is one of the disastrous phenomena in a communication channel.In this paper,a dual input single output(DISO)Hm controller is designed to build the control resiliency by employing two highest observability ranking wide area signals with respect to the critical damping inter-area mode.The proposed controller can provide sufficient damping to the system and also the system remains stabilized if one of the wide-area signals is lost.The time delay is an unwanted phenomenon that degrades the performance of the controllers.The unified Smith predictor approach is used to design a Hm controller to handle the time delay.Kundur's two-area and IEEE-39 bus test systems are considered to verify the effectiveness of the proposed controller.From the simulation results,it is verified that,the proposed controller provides excellent damping performance at normal communication and improves the controller resiliency to counteract the communication failure.
基金supported by the Natural Science Foundation of Shanghai(09ZR1430500)the Chinese National Science and Technology Major Project(2011ZX03003-001-01,2009ZX03002-003-004)
文摘The feedback delay can severely affect the quality of the channel state information at the transmitter(CSIT)which is fed back from the receiver.The outdated CSIT will cause large performance loss in the transmit beamforming systems.The effect of variable feedback delay on the capacity of transmit beamforming systems over Rayleigh fading channels is studied.First,the case of fixed feedback delay is considered and a closed-form expression of system capacity is derived.Based on the results of fixed delay,the delay following certain distributions in variable delay case is assumed and the closed-form expressions of capacities are derived.The closed-form expressions show that the capacity is significantly affected by the statistical characteristics of the feedback delay.The obtained results provide an analytical insight into the effects caused by variable delay on the system capacity.
文摘An on-board charger for efficiently charging multiple battery-operated electric vehicles(EVs)is introduced.It has evolved as a single-input dual-output(SIDO)integrated boost-single ended primary inductor converter(SEPIC)fly-back converter,offering cost-effectiveness,reliability,and higher efficiency compared to conventional chargers with equivalent specifications.The proposed system includes an additional regulated output terminal,in addition to an existing terminal for charging the EV battery of a 4-wheeler,which can be used to charge another EV battery,preferably a 2-wheeler.With the aid of control techniques,unity power factor operations are obtained during constant-voltage(CV)/constant-current(CC)charging for the grid-to-vehicle(G2V)operating mode.Using mathematical modelling analysis,the proposed system is developed in a Matlab/Simulink environment,and the results are validated in a real-time simulator using dSPACE-1104.The proposed system is employed for charging the batteries of two EVs with capacities of 400 V,40 A·h and 48 V,52 A·h for the 4-wheeler and 2-wheeler,respectively.Its performance is investigated under different operating modes and over a wide range of supply voltage variations to ensure safe and reliable operation of the charger.
