电机与控制应用
電機與控製應用
전궤여공제응용
Electric Machines & Control Application
2015年
10期
12-17
,共6页
三电平逆变器%空间矢量调制%控制因子%中点电压平衡
三電平逆變器%空間矢量調製%控製因子%中點電壓平衡
삼전평역변기%공간시량조제%공제인자%중점전압평형
three-level inverter%space vector modulation%control factor%neutral-point voltage balance
二极管钳位式三电平逆变器的拓扑结构导致了中点电位的不平衡,其实质在于有电流流过直流侧的电容中点. 准双极性调制策略能充分利用冗余电压小矢量抑制中点电压波动,但对深度调制时中矢量引起的电位波动却无能为力. 为此提出一种抑制中点电位波动的有效控制方法. 该方法基于首发矢量为正小矢量的准双极性调制策略,并引入一个控制因子k,根据直流侧中点电位重新分配下一个采样周期内的正、负小矢量作用时间,以此来实时控制流入电容中点的电荷量,减小中点电位的波动. 为便于硬件实现,减少窄脉冲的发生,又对k进行了分级控制设计. Simulink仿真结果验证了该方法的有效性.
二極管鉗位式三電平逆變器的拓撲結構導緻瞭中點電位的不平衡,其實質在于有電流流過直流側的電容中點. 準雙極性調製策略能充分利用冗餘電壓小矢量抑製中點電壓波動,但對深度調製時中矢量引起的電位波動卻無能為力. 為此提齣一種抑製中點電位波動的有效控製方法. 該方法基于首髮矢量為正小矢量的準雙極性調製策略,併引入一箇控製因子k,根據直流側中點電位重新分配下一箇採樣週期內的正、負小矢量作用時間,以此來實時控製流入電容中點的電荷量,減小中點電位的波動. 為便于硬件實現,減少窄脈遲的髮生,又對k進行瞭分級控製設計. Simulink倣真結果驗證瞭該方法的有效性.
이겁관겸위식삼전평역변기적탁복결구도치료중점전위적불평형,기실질재우유전류류과직류측적전용중점. 준쌍겁성조제책략능충분이용용여전압소시량억제중점전압파동,단대심도조제시중시량인기적전위파동각무능위력. 위차제출일충억제중점전위파동적유효공제방법. 해방법기우수발시량위정소시량적준쌍겁성조제책략,병인입일개공제인자k,근거직류측중점전위중신분배하일개채양주기내적정、부소시량작용시간,이차래실시공제류입전용중점적전하량,감소중점전위적파동. 위편우경건실현,감소착맥충적발생,우대k진행료분급공제설계. Simulink방진결과험증료해방법적유효성.
Topology structure of diode-clamped three-level inverter leads to its neutral voltage balance problems, the essence of the neutral-point potential variation lie in the current which through the Capacitance midpoint of the DC side. Although semi-bipolar PWM pattern can take full advantage of redundancy small voltage vector, and be beneficial to restrain the neutral-point voltage potential variation, it is helplessness to the potential variation caused by medium-vector, especially at high modulation depth. Based on a semi-bipolar PWM pattern strategy where positive small vectors were adopted as first active vector, and a control factor k was introduced, so according to the neutral-point voltage potential variation of the DC side, we could redistribute the action time of the positive or negative small vector in next sampling period. It was able to control the charge of capacitance in real-time, and reduced the neutral-point voltage variation. For the convenience of hardware realization and decrease narrow pulse generation, the control factor k was classified. Finally, the effectiveness of proposed approach was confirmed via Simulink simulation results.