能馈式级联型高压变频器运行特性研究

基于传统级联型变频器驱动的高压异步电动机只能电动运行,为克服这一不足,提出了一种能馈式级联型高压变频器。用PWM整流器替代传统级联单元的不控整流桥,并对输入电流进行直接控制,在异步电动机处于再生制动状态时,输入电流自动反相,将再生能量回馈到电网,进而实现异步电动机的再生运行。所提出的新型高压变频器具有输入电流波形近似正弦,谐波污染小,自动实现能量双向流动,节能效果明显等优点。仿真和实验研究结果证明了该新型变频器的正确性和可行性。

Study on Operating Characteristics of Regenerative Cascade High Voltage Inverter

High voltage induction motor driven by traditional cascade inverter can only operate in electrical statement.A regenerative cascade high voltage inverter is proposed.Through replacing the non-control rectifier bridge by the PWM rectifier,the input currents are controlled directly.When the induction motor is in the regenerative braking statement,the phase of input current is inversed automatically,the regenerative power is feeding back into power line,thus the regenerative operation of induction motor is realized.The proposed regenerative cascade inverter has the merits that the input current is near sinusoidal,the bi-directional flow of the power is realized automatically.The simulative and experimental results indicate its validity and feasibility.