CAJ | 학술논문

对于中点箝位式三电平有源电力滤波器，建立了中线电流与中线电压的定量数学模型。基于上述模型，提出了一种三电平中点电位控制方法。通过引入表示中线电流与电容中点电位关系的系数，可以根据上下电容电压差直接计算出注入的中线电流的合理值。同时通过合理选择滤波器参数与采样频率，可以抑制该方法对于 APF 补偿效果的影响。仿真与实验研究结果表明，该方法在基本不影响补偿效果的同时可消除中点电位不平衡。
대우중점겸위식삼전평유원전력려파기，건립료중선전류여중선전압적정량수학모형。기우상술모형，제출료일충삼전평중점전위공제방법。통과인입표시중선전류여전용중점전위관계적계수，가이근거상하전용전압차직접계산출주입적중선전류적합리치。동시통과합리선택려파기삼수여채양빈솔，가이억제해방법대우 APF 보상효과적영향。방진여실험연구결과표명，해방법재기본불영향보상효과적동시가소제중점전위불평형。
A quantitative mathematical model for neutral current and neutral voltage in neutral point clamping (NPC) three-phase four-wire tri-level active power filter (AFP) is established. Based on the established model, a control method for neutral point potential of tri-level APF is proposed. Leading in a coefficient representing the relation between neutral current and neutral potential of capacitor, according to the voltage difference between upper capacitor and lower capacitor the reasonable value of neutral current to be injected can be calculated directly. Meanwhile, by means of reasonably choosing filter parameters and sampling frequency, the effect of the proposed control method on the compensation effect of APF can be suppressed. Results of simulation and experiments show that using the proposed method the neutral potential unbalance can be eliminated when the compensation effect of APF is basically not affected.