传统有限控制集的模型预测控制(finite control set model predictive control,FCS-MPC)在一个控制周期内输出单一的开关状态,当采样频率较低时,控制精度较差,且开关频率不固定导致交流侧滤波器难以设计。针对上述问题,在传统FCS-MPC的...传统有限控制集的模型预测控制(finite control set model predictive control,FCS-MPC)在一个控制周期内输出单一的开关状态,当采样频率较低时,控制精度较差,且开关频率不固定导致交流侧滤波器难以设计。针对上述问题,在传统FCS-MPC的基础上,为三相脉冲宽度调制(pulsewidth modulation,PWM)整流器提出一种基于功率跟踪目标函数的定频模型预测控制。首先基于FCS-MPC的功率跟踪目标函数最小值求解,精确计算变换器输出电压矢量的扇区,接着根据扇区确定控制周期作用的两个有效矢量和零矢量,最后利用3个矢量的功率跟踪差值计算各电压矢量的作用时间。通过仿真验证,与传统FCS-MPC相比,所提方法能实现开关频率的固定,减小功率脉动,提高整流器的输出性能。展开更多
提出了一种新型的控制策略,将模型预测(Model Predict Control,MPC)控制应用于PWM整流器的直接功率控制(Direct Power Control,DPC)中。这种控制方法是在开关频率固定的情况下以功率误差最小为原则来选择最佳的电压矢量。此外,还设计了...提出了一种新型的控制策略,将模型预测(Model Predict Control,MPC)控制应用于PWM整流器的直接功率控制(Direct Power Control,DPC)中。这种控制方法是在开关频率固定的情况下以功率误差最小为原则来选择最佳的电压矢量。此外,还设计了控制延时补偿方案,用以消除控制延时所产生的功率误差。实验结果表明这种控制策略不仅实现了网侧电流正弦化和单位功率因数,而且还获得了更好的稳态性能和更快的动态响应速度。该控制策略以新颖的方法实现了定频直接功率控制,简化了整流器系统参数的设计。展开更多
In the conventional cascade control structure of aerospace electrically powered actuators, the current(or electromagnetic torque) loop plays a critical role in realizing a rapid response for a digitally controlled B...In the conventional cascade control structure of aerospace electrically powered actuators, the current(or electromagnetic torque) loop plays a critical role in realizing a rapid response for a digitally controlled Brush Less Direct Current(BLDC) motor. Hysteresis Current Control(HCC) is an effective method in improving the performance of current control for a BLDC motor.Nevertheless, the varying modulating frequency in the traditional HCC causes severe problems on the safety of power devices and the electromagnetic compatibility design. A triangular carrier-based fixed-frequency HCC strategy is expanded by relaxing the constraints on the rising and descending rates of the winding current to advance the capability of HCC to realize fixed-frequency modulation in the steady state. Based on that, a new flexible-bound-size quasi-fixed-frequency HCC is proposed, and the range feasible to realize fixed-frequency modulation control can cover the entire running process in the steady state. Meanwhile, a corresponding digital control strategy is designed,and four digitalization rules are proposed to extend the capacity to achieve fixed-frequency modulation control to the unsteady working state, that is, a novel fixed-frequency modulation is realized.Simulation and experimental results prove the effectiveness of this improved fixed-frequency HCC strategy.展开更多
文摘传统有限控制集的模型预测控制(finite control set model predictive control,FCS-MPC)在一个控制周期内输出单一的开关状态,当采样频率较低时,控制精度较差,且开关频率不固定导致交流侧滤波器难以设计。针对上述问题,在传统FCS-MPC的基础上,为三相脉冲宽度调制(pulsewidth modulation,PWM)整流器提出一种基于功率跟踪目标函数的定频模型预测控制。首先基于FCS-MPC的功率跟踪目标函数最小值求解,精确计算变换器输出电压矢量的扇区,接着根据扇区确定控制周期作用的两个有效矢量和零矢量,最后利用3个矢量的功率跟踪差值计算各电压矢量的作用时间。通过仿真验证,与传统FCS-MPC相比,所提方法能实现开关频率的固定,减小功率脉动,提高整流器的输出性能。
文摘提出了一种新型的控制策略,将模型预测(Model Predict Control,MPC)控制应用于PWM整流器的直接功率控制(Direct Power Control,DPC)中。这种控制方法是在开关频率固定的情况下以功率误差最小为原则来选择最佳的电压矢量。此外,还设计了控制延时补偿方案,用以消除控制延时所产生的功率误差。实验结果表明这种控制策略不仅实现了网侧电流正弦化和单位功率因数,而且还获得了更好的稳态性能和更快的动态响应速度。该控制策略以新颖的方法实现了定频直接功率控制,简化了整流器系统参数的设计。
基金supported by the National Natural Science Foundation of China (Nos.51275021,61327807)
文摘In the conventional cascade control structure of aerospace electrically powered actuators, the current(or electromagnetic torque) loop plays a critical role in realizing a rapid response for a digitally controlled Brush Less Direct Current(BLDC) motor. Hysteresis Current Control(HCC) is an effective method in improving the performance of current control for a BLDC motor.Nevertheless, the varying modulating frequency in the traditional HCC causes severe problems on the safety of power devices and the electromagnetic compatibility design. A triangular carrier-based fixed-frequency HCC strategy is expanded by relaxing the constraints on the rising and descending rates of the winding current to advance the capability of HCC to realize fixed-frequency modulation in the steady state. Based on that, a new flexible-bound-size quasi-fixed-frequency HCC is proposed, and the range feasible to realize fixed-frequency modulation control can cover the entire running process in the steady state. Meanwhile, a corresponding digital control strategy is designed,and four digitalization rules are proposed to extend the capacity to achieve fixed-frequency modulation control to the unsteady working state, that is, a novel fixed-frequency modulation is realized.Simulation and experimental results prove the effectiveness of this improved fixed-frequency HCC strategy.