The start-up current control of the high-speed brushless DC(HS-BLDC) motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is ...The start-up current control of the high-speed brushless DC(HS-BLDC) motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network(ANN)inverse system and the two degrees of freedom(2-DOF) internal model controller(IMC). The HS-BLDC motor is identified by the online least squares support vector machine(OLS-SVM) algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.展开更多
The tokamak start-up is a very important phase during the process to obtain a suitable equalizing plasma, and its governing model can be described as a set of nonlinear ordinary differential equations(ODEs). In this...The tokamak start-up is a very important phase during the process to obtain a suitable equalizing plasma, and its governing model can be described as a set of nonlinear ordinary differential equations(ODEs). In this paper, we first estimate the parameters in the original model and set up an accurate model to express how the variables change during the start-up phase, especially how the plasma current changes with respect to time and the loop voltage. Then, we apply the control parameterization method to obtain an approximate optimal parameters selection problem for the loop voltage design to achieve a desired plasma current target. Computational optimal control techniques such as the variational method and the costate method are employed to solve the problem, respectively. Finally, numerical simulations are performed and the results obtained via different methods are compared. Our numerical parameterization method and optimization procedure turn out to be effective.展开更多
Controlling the poloidal field (PF) in the HT-7U superconducting tokamak is critical to the realization of the mission of advanced tokamak research. Plasma start-up, plasma position, shape, current control and plasma ...Controlling the poloidal field (PF) in the HT-7U superconducting tokamak is critical to the realization of the mission of advanced tokamak research. Plasma start-up, plasma position, shape, current control and plasma shape reconstruction have been performed as a part of its design process. The PF coils have been designed to produce a wide range of plasmas. Plasma start-up can be achieved for multiple conditions. Fast controlling coils for plasma position inside the vacuum vessel are used for controlling the plasma vertical position on a short timescale. The PF coils control the plasma current and shape on a slower timescale. VXI (VME bus extensions for Instrumentation) Bus system and DSP (Digital Signal Processor is a basic unit of the feedback control system), the response time of which is about (2-4) ms. The basic unit of this system, the shape-controlling algorithms of a few critical points on plasma boundary and real-time equilibrium fitting (RTEFIT) will be described in this paper.展开更多
中压设备是列车上较大功率的设备,这些设备分散在列车各系统中,由辅助供电系统集中为其供电。由于电感效应,中压设备启动时的峰值电流会对辅助供电系统的安全性和稳定性产生不利影响。为保证列车辅助供电系统稳定、可靠运行,需要有效地...中压设备是列车上较大功率的设备,这些设备分散在列车各系统中,由辅助供电系统集中为其供电。由于电感效应,中压设备启动时的峰值电流会对辅助供电系统的安全性和稳定性产生不利影响。为保证列车辅助供电系统稳定、可靠运行,需要有效地控制中压设备启动时的峰值电流。基于列车控制与管理系统(TCMS,Train Control and Management System)的控制逻辑,研究列车上电自检阶段中压设备错时顺序启动控制方法,列车运行中空调压缩机错时启动控制方法,以及辅助供电系统故障工况下中压设备减载启动控制方法,避免中压负载峰值电流叠加对辅助供电系统造成的不良影响,确保在故障情况下有足够的辅助供电能力。通过实验室仿真测试和运营线上实车试验,初步验证了在辅助供电备用率和启动峰值电流的限制约束下,列车中压设备启动控制方法的有效性。展开更多
基金co-supported by the National Major Project for the Development and Application of Scientific Instrument Equipment of China (No. 2012YQ040235)
文摘The start-up current control of the high-speed brushless DC(HS-BLDC) motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network(ANN)inverse system and the two degrees of freedom(2-DOF) internal model controller(IMC). The HS-BLDC motor is identified by the online least squares support vector machine(OLS-SVM) algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.
基金supported by the National Natural Science Foundation of China(Grant Nos.61104048 and 61473253)the National High Technology Research and Development Program of China(Grant No.2012AA041701)
文摘The tokamak start-up is a very important phase during the process to obtain a suitable equalizing plasma, and its governing model can be described as a set of nonlinear ordinary differential equations(ODEs). In this paper, we first estimate the parameters in the original model and set up an accurate model to express how the variables change during the start-up phase, especially how the plasma current changes with respect to time and the loop voltage. Then, we apply the control parameterization method to obtain an approximate optimal parameters selection problem for the loop voltage design to achieve a desired plasma current target. Computational optimal control techniques such as the variational method and the costate method are employed to solve the problem, respectively. Finally, numerical simulations are performed and the results obtained via different methods are compared. Our numerical parameterization method and optimization procedure turn out to be effective.
基金This work was supported by the National Meg-science Engineering Project of the Chinese Government
文摘Controlling the poloidal field (PF) in the HT-7U superconducting tokamak is critical to the realization of the mission of advanced tokamak research. Plasma start-up, plasma position, shape, current control and plasma shape reconstruction have been performed as a part of its design process. The PF coils have been designed to produce a wide range of plasmas. Plasma start-up can be achieved for multiple conditions. Fast controlling coils for plasma position inside the vacuum vessel are used for controlling the plasma vertical position on a short timescale. The PF coils control the plasma current and shape on a slower timescale. VXI (VME bus extensions for Instrumentation) Bus system and DSP (Digital Signal Processor is a basic unit of the feedback control system), the response time of which is about (2-4) ms. The basic unit of this system, the shape-controlling algorithms of a few critical points on plasma boundary and real-time equilibrium fitting (RTEFIT) will be described in this paper.
文摘中压设备是列车上较大功率的设备,这些设备分散在列车各系统中,由辅助供电系统集中为其供电。由于电感效应,中压设备启动时的峰值电流会对辅助供电系统的安全性和稳定性产生不利影响。为保证列车辅助供电系统稳定、可靠运行,需要有效地控制中压设备启动时的峰值电流。基于列车控制与管理系统(TCMS,Train Control and Management System)的控制逻辑,研究列车上电自检阶段中压设备错时顺序启动控制方法,列车运行中空调压缩机错时启动控制方法,以及辅助供电系统故障工况下中压设备减载启动控制方法,避免中压负载峰值电流叠加对辅助供电系统造成的不良影响,确保在故障情况下有足够的辅助供电能力。通过实验室仿真测试和运营线上实车试验,初步验证了在辅助供电备用率和启动峰值电流的限制约束下,列车中压设备启动控制方法的有效性。