电流源型脉宽调制(Pulse width modulation,PWM)整流器因其网侧存在LC滤波器,系统的控制难度增加。传统直接功率控制策略下的整流器功率波形存在脉动,因模型预测控制具有卓越的动态特性以及直观的控制规律,采用模型预测直接功率控制(Mod...电流源型脉宽调制(Pulse width modulation,PWM)整流器因其网侧存在LC滤波器,系统的控制难度增加。传统直接功率控制策略下的整流器功率波形存在脉动,因模型预测控制具有卓越的动态特性以及直观的控制规律,采用模型预测直接功率控制(Model predictive direct power control,MPDPC)对传统控制策略进行改进。首先建立了三相PWM整流器的数学模型,给出了每个采样周期内的功率变化率,并推导出相邻采样周期之间的功率关系,然后给出基于单矢量的模型预测直接功率控制策略,提出了基于双矢量的模型预测直接功率控制策略,并优选出两个电流矢量,计算在一个采样周期内的作用时间,并对其进行修正。最后,在Matlab/Simulink仿真软件验证了所提控制策略的可行性和有效性。展开更多
模型预测直接功率控制(MPDPC)以其原理简单、动态响应快和控制目标灵活等优点在并网变换器控制中得到了广泛关注。它利用系统模型来预测下一时刻的有功功率和无功功率,通过枚举比较得到使给定功率和反馈功率之间误差最小的电压矢量,相...模型预测直接功率控制(MPDPC)以其原理简单、动态响应快和控制目标灵活等优点在并网变换器控制中得到了广泛关注。它利用系统模型来预测下一时刻的有功功率和无功功率,通过枚举比较得到使给定功率和反馈功率之间误差最小的电压矢量,相比传统的基于矢量表的直接功率控制具有更好的动态和稳态性能。为了进一步提高稳态性能并降低采样频率,提出一种基于双矢量的改进模型预测直接功率控制,即把一个控制周期分配给一个非零矢量和一个零矢量,通过优化非零矢量的作用时间来进一步减小功率脉动。通过合理安排矢量作用顺序甚至可以获得比传统MPDPC更低的开关频率而且稳态性能更好。在15 k W双馈风力发电系统上的仿真结果表明,相比传统MPDPC,所提出的双矢量MPDPC能够以更低的采样频率实现快速平滑的并网同步和灵活的有功、无功控制,并且开关频率更低,具有较大的实用价值。展开更多
For a permanent magnet synchronous motor(PMSM)model predictive current control(MPCC)system,when the speed loop adopts proportional-integral(PI)control,speed regulation is easily affected by motor parameters,resulting ...For a permanent magnet synchronous motor(PMSM)model predictive current control(MPCC)system,when the speed loop adopts proportional-integral(PI)control,speed regulation is easily affected by motor parameters,resulting in the inability to balance the system robustness and dynamic performance.A PMSM optimal control strategy combining linear active disturbance rejection control(LADRC)and two-vector MPCC(TV-MPCC)is proposed.Firstly,a mathematical model of a PMSM is presented,and the PMSM TV-MPCC model is developed in the synchronous rotation coordinate system.Secondly,a first-order LADRC controller composed of a linear extended state observer and linear state error feedback is designed to reduce the complexity of parameter tuning while linearly simplifying the traditional active disturbance rejection control(ADRC)structure.Finally,the conventional PI speed regulator in the motor speed control system is replaced by the designed LADRC controller.The simulation results show that the speed control system using LADRC can effectively deal with the changes in motor parameters and has better robustness and dynamic performance than PI control and similar methods.The system has a fast motor speed response,small overshoot,strong anti-interference,and no steady-state error,and the total harmonic distortion is reduced.展开更多
文摘电流源型脉宽调制(Pulse width modulation,PWM)整流器因其网侧存在LC滤波器,系统的控制难度增加。传统直接功率控制策略下的整流器功率波形存在脉动,因模型预测控制具有卓越的动态特性以及直观的控制规律,采用模型预测直接功率控制(Model predictive direct power control,MPDPC)对传统控制策略进行改进。首先建立了三相PWM整流器的数学模型,给出了每个采样周期内的功率变化率,并推导出相邻采样周期之间的功率关系,然后给出基于单矢量的模型预测直接功率控制策略,提出了基于双矢量的模型预测直接功率控制策略,并优选出两个电流矢量,计算在一个采样周期内的作用时间,并对其进行修正。最后,在Matlab/Simulink仿真软件验证了所提控制策略的可行性和有效性。
文摘模型预测直接功率控制(MPDPC)以其原理简单、动态响应快和控制目标灵活等优点在并网变换器控制中得到了广泛关注。它利用系统模型来预测下一时刻的有功功率和无功功率,通过枚举比较得到使给定功率和反馈功率之间误差最小的电压矢量,相比传统的基于矢量表的直接功率控制具有更好的动态和稳态性能。为了进一步提高稳态性能并降低采样频率,提出一种基于双矢量的改进模型预测直接功率控制,即把一个控制周期分配给一个非零矢量和一个零矢量,通过优化非零矢量的作用时间来进一步减小功率脉动。通过合理安排矢量作用顺序甚至可以获得比传统MPDPC更低的开关频率而且稳态性能更好。在15 k W双馈风力发电系统上的仿真结果表明,相比传统MPDPC,所提出的双矢量MPDPC能够以更低的采样频率实现快速平滑的并网同步和灵活的有功、无功控制,并且开关频率更低,具有较大的实用价值。
文摘For a permanent magnet synchronous motor(PMSM)model predictive current control(MPCC)system,when the speed loop adopts proportional-integral(PI)control,speed regulation is easily affected by motor parameters,resulting in the inability to balance the system robustness and dynamic performance.A PMSM optimal control strategy combining linear active disturbance rejection control(LADRC)and two-vector MPCC(TV-MPCC)is proposed.Firstly,a mathematical model of a PMSM is presented,and the PMSM TV-MPCC model is developed in the synchronous rotation coordinate system.Secondly,a first-order LADRC controller composed of a linear extended state observer and linear state error feedback is designed to reduce the complexity of parameter tuning while linearly simplifying the traditional active disturbance rejection control(ADRC)structure.Finally,the conventional PI speed regulator in the motor speed control system is replaced by the designed LADRC controller.The simulation results show that the speed control system using LADRC can effectively deal with the changes in motor parameters and has better robustness and dynamic performance than PI control and similar methods.The system has a fast motor speed response,small overshoot,strong anti-interference,and no steady-state error,and the total harmonic distortion is reduced.
