摘要
PWM整流器的带载能力是动态电压恢复器在不同电压补偿深度下直流侧电压稳定的关键。针对PWM整流器带重载时直流侧电压不稳定的现象,定性分析了直流侧电压稳定与其带载能力的关系,得出了定参数下最大跟踪电流值以及直流侧电压与各参数量的关系,揭示了直流侧电容电压随电路参数变化的原理,并建立了单相PWM整流器带载能力数学模型;然后通过分析功率平衡与带载能力的关系得出逆变基波电压相位滞后电网电压相位的范围,利用该方法分析单相PWM整流器带载能力与基于直流侧电压稳定分析的结果一致;最后探讨了直流侧电容电压二次纹波对单相PWM整流器带载能力的影响,提出了通过调节电压外环比例系数改善其带载能力的方法。仿真和实验结果验证了上述理论分析的正确性。
Loading capacity of PWM rectifier plays key role in DVR＇s DC voltage stability under different voltage compensation degrees. According to unstable phenomenon of DC voltage resulting from PWM rectifier overloading, firstly, based on relationship between DC voltage and load capacity, maximum value of follow current and relationship between DC voltage and each circuit parameter were obtained. It revealed adjustment principle of DC voltage by changing circuit parameters and established mathematic model of PWM rectifier＇s loading capacity. Phase-lag scope of inverter＇s fundamental voltage relative to power grid voltage was obtained by analyzing relation of power balance with load. With this method, result of mathematic model of PWM rectifier load was consistent with DC voltage stability analysis. Influence of secondary ripple voltage in DC side on PWM rectifier＇s load capacity was discussed. An outer loop controller optimization method was put forward to reduce ripple voltage influence. Finally, correctness of the theoretical analysis was verified with simulation and experiment.
出处
《电网技术》
EI
CSCD
北大核心
2017年第1期230-237,共8页
Power System Technology
基金
国家自然科学基金项目(51377051)~~
