配电台区无功功率及三相不平衡电容调节的研究

针对我国配电台区普遍存在无功不足和三相不平衡的问题,通过相间电容和分相电容来实现无功功率和三相不平衡的调节。分析了相间和分相跨接电容进行无功功率和三相不平衡调节的原理。以补偿后系统三相不平衡度最小为目标,采用非线性约束优化算法计算出最优的补偿容量配置。并以功率因数为0.4～0.9、不平衡度为0～50%、负载率为40%～70%的400 kVA配电台区变压器为验证模型,给出了不同变压器工况下补偿电容容量的选择方案。通过仿真和工程应用验证了该电容调节方法的正确性,最后给出了电容调节方法的适用范围。

Study on reactive power and three-phase unbalance regulated by capacitor in distribution network

In view of the problems of reactive power and three-phase unbalance existing in distribution networks in China, this paper realizes the regulation of reactive power and three-phase unbalance by using phase-to-phase capacitor and split-phase capacitor and analyzes the principle of the above regulation method. Taken three-phase unbalanced degree minimum after compensation as the objective, the optimal allocation of the compensation capacity is calculated by applying nonlinear constrained optimization algorithm. Taking the 400 kVA substation transformer when power factor is 0.4~0.9, unbalanced degree is 0~50% and load ratio is 40%~70% as the verification model, this paper gives the selection schemes of the compensation capacitor capacity under different working conditions. By simulation and engineering application, the method of the capacitor regulation proves to be correct and finally the application range of the method is worked out. This work is supported by National Natural Science Foundation of China (No. 51507138).