摘要
在级联型多电平变换器的功率单元中,用PWM整流器替代二极管整流器,可以实现能量的双向流动;利用隔离变压器的副边漏抗代替整流器的输入电抗器,可以减少变换器的体积和成本;隔离变压器的副边绕组移相消除了由单个功率单元所引起的谐波电流,抑制了网侧谐波尤其是低次谐波的产生。在整流器控制中使用锁相环对电网的相位和频率跟踪,采用PWM整流器的PIR电流控制策略,有利于在整流器接单相逆变负载的情况下维持母线电压的稳定。给出了PWM整流器的数学模型、定向策略及PIR控制策略,通过实验验证了新型整流器及其控制策略在电机加速减速过程中能够实现能量回馈。
In the power units of cascaded multilevel converters, replacing the diode rectifier with PWM rectifier can make the converter have the regenerative abitity; using the leak inductance as the filter reactor of the PWM rectifier can reduce the volume and cost of the converter; the phase-shift secondary side of the trans- former can eliminate the current harmonics caused by the single power unit, restraining the grid side harmonic especially the low order harmonic. In the control scheme PLL is employed to track the grid voltage＇s phase and frequency. The PIR control strategy of the PWM rectifier is used to maintain the DC-link voltage stable when feeding the single-phase inverter. The mathematic model of the PWM rectifier, its orientation method and the PIR current control strategy were introduced. The experiment results verify that the converter can achieve the regenerative abilitv when operating in the accelerating and decelerating of electrical machines.
出处
《电气传动》
北大核心
2011年第3期19-23,共5页
Electric Drive
