为提高模块化多电平高压直流输电系统在电网电压不平衡时的运行能力,提出一种新型不平衡控制策略。该策略在正向同步旋转坐标系下电流比例积分(proportional integral,PI)闭环控制的基础上引入以抑制负序电流、抑制有功波动或抑制无功...为提高模块化多电平高压直流输电系统在电网电压不平衡时的运行能力,提出一种新型不平衡控制策略。该策略在正向同步旋转坐标系下电流比例积分(proportional integral,PI)闭环控制的基础上引入以抑制负序电流、抑制有功波动或抑制无功波动为控制目标的辅助控制器,避免了电压、电流正负序分解和繁琐的指令电流计算。为实现上述3种控制目标,对二阶广义积分器(second order generalized integrator,SOGI)、降阶广义积分器(reduced order generalized integrator,ROGI)和降阶矢量比例积分器(reduced order vector proportional integrator,ROVPI)这3种控制器进行了研究对比。研究发现,SOGI作为辅助控制器将产生3次正序谐波,导致电流畸变;与ROGI相比,ROVPI具有更好的控制精度和相位裕度,因此选择ROVPI作为辅助控制器。仿真结果验证所提不平衡控制策略的正确性和有效性。展开更多
Dynamic characteristics and tracking precision are studied in the photoelectric tracking system and a linear active disturbance rejection control( LADRC) scheme is proposed for position loop. A current and speed contr...Dynamic characteristics and tracking precision are studied in the photoelectric tracking system and a linear active disturbance rejection control( LADRC) scheme is proposed for position loop. A current and speed controller is designed by a transfer function model,which is obtained by adaptive differential evolution. Model error,friction and nonlinear factor existing in position loop are treated as ‘disturbance',which is estimated and compensated by generalized proportional integral( GPI)observer. Comparative results are provided to demonstrate the remarkable performance of the proposed method. It turns out that the proposed scheme is successful and has superior features,such as quick dynamic response,low overshoot and high tracking precision. Furthermore,with the proposed method,friction is suppressed effectively.展开更多
文摘为提高模块化多电平高压直流输电系统在电网电压不平衡时的运行能力,提出一种新型不平衡控制策略。该策略在正向同步旋转坐标系下电流比例积分(proportional integral,PI)闭环控制的基础上引入以抑制负序电流、抑制有功波动或抑制无功波动为控制目标的辅助控制器,避免了电压、电流正负序分解和繁琐的指令电流计算。为实现上述3种控制目标,对二阶广义积分器(second order generalized integrator,SOGI)、降阶广义积分器(reduced order generalized integrator,ROGI)和降阶矢量比例积分器(reduced order vector proportional integrator,ROVPI)这3种控制器进行了研究对比。研究发现,SOGI作为辅助控制器将产生3次正序谐波,导致电流畸变;与ROGI相比,ROVPI具有更好的控制精度和相位裕度,因此选择ROVPI作为辅助控制器。仿真结果验证所提不平衡控制策略的正确性和有效性。
基金Supported by the National High Technology Research and Development Programme of China(No.2015AA8082065)the National Natural Science Foundation of China(No.61205143)
文摘Dynamic characteristics and tracking precision are studied in the photoelectric tracking system and a linear active disturbance rejection control( LADRC) scheme is proposed for position loop. A current and speed controller is designed by a transfer function model,which is obtained by adaptive differential evolution. Model error,friction and nonlinear factor existing in position loop are treated as ‘disturbance',which is estimated and compensated by generalized proportional integral( GPI)observer. Comparative results are provided to demonstrate the remarkable performance of the proposed method. It turns out that the proposed scheme is successful and has superior features,such as quick dynamic response,low overshoot and high tracking precision. Furthermore,with the proposed method,friction is suppressed effectively.
