三相四线制系统中的微电源控制

Micro source control of three-phase four-wire system

研究了基于逆变器并网的微电源在三相四线制微电网中的多目标控制问题。由节点电压的实时采样获得其相位和幅值的估计;采用比例积分控制由微电源有功输出误差确定网侧有功设定;依据网侧有功和无功设定,同时考虑三相不平衡和谐波补偿的要求,确定网侧电流的参考值;将实际负荷电流减去网侧电流的参考值获得微电源输出电流的参考值,通过滞环控制实现微电源输出电流对参考电流的快速跟踪,实现了输出功率、三相不平衡补偿和谐波补偿的多目标控制。针对开关动态对节点电压采样值的干扰,引入带通滤波,滤除高频动态的同时避免了常规低频滤波的延时。基于Simulink的仿真结果验证了上述策略的有效性。

The multi-objective control of micro source is studied for three-phase four-wire system.The phase and magnitude of node voltage are estimated according its real time measurement;the grid-side setting P is regulated by the PI controller according to the real output of micro source;the grid-side reference current is set according to the grid-side setting P and Q,as well as the requirements for unbalance and harmonic compensation;the reference current of micro source is obtained by subtracting the grid-side reference current from load current.The multi-objective control is implemented by a hysteresis control of micro source output current,which follows the reference current quickly.Band pass filter is adopted to remove the high-frequency switching disturbance in node voltage measurements and avoid the time delay of common low pass filter.The control strategy is verified by simulation on Simulink platform.