基于比例谐振调节器的逆变器双环控制策略研究

摘要

逆变器采用比例谐振（PR）调节理论上能够实现无静差的输出电压。分析比较了数字实现的谐振控制器在两种离散方式下的特性,选择了脉冲不变法作为谐振控制器的离散方法。以单相全桥逆变器为研究对象,在离散域上详细设计了采用PR调节的双环数字控制策略;加入多个谐波谐振控制器减小非线性负载对输出电压的影响。分析比较了PR调节和PI调节两种策略下的输出外特性。理论分析和实验结果表明,采用该方案的逆变器具有优良的输出特性。%Output voltage of the inverter can be obtained without steady state error using proportional-resonant （PR） control. The characteristics of digital resonant controller under two discrete forms are analyzed and compared, and it finally comes to be used with impulse invariant method. Double-loop control strategy based on PR control is designed detailedly in the discrete region. In order to reduce the influence of nonlinear load on output voltage, several harmonic resonant controllers are adopted. Both theory analysis and experimental result show that the inverter based on PR control has superior output characteristic using this method.