配电变压器负荷不平衡有源补偿技术应用研究

随着配网建设的推进和用电负荷的广泛接入,配电变压器负荷三相不平衡问题日益突出,本文研究有源三相不平衡补偿装置在配电台区的应用技术。首先指出了负荷三相不平衡带来的问题,并从理论上分析了该装置提高台区电能质量、降低配变和线路损耗的原理;然后基于贵州电科院“电网节能降损技术实验室”平台,模拟实际配变、线路及负荷情况,验证了该装置能在调节负荷不平衡的同时补偿无功,实验中还通过控制变量法得出影响装置降损效果的两个关键因数：装置接入点至变压器之间低压线路长度、装置自身效率,进而提出有源补偿装置应用于台区三相不平衡治理的技术改进方向;最后,在贵阳供电局安装了两台有源补偿装置,现场运行结果验证了理论分析和实验测试结果的正确性。

Application Research of Active Compensation Technology for Load Unbalance of Distribution Transformer

With the development of distribution network and the wide access of power load, the unbalanced three-phase load problem of distribution transformers is becoming more and more serious. In this paper, the active three-phase unbalanced compensation device is applied to the distribution area. Firstly, problems brought by the unbalanced three-phase load is pointed out. Meanwhile the principle of power quality improvement and loss reduction of the distribution area is analyzed. Secondly, actual distribution transformer, line and load conditions are simulated based on the "power grid energy saving and loss reduction technology laboratory". Experiment results verify that the device can compensate reactive power while adjusting the load imbalance. Two key factors that affect the loss reduction effect of the device are obtained through the variable control method: the length of the power line between the device access point and the transformer and the efficiency of the device itself. Furthermore technical improvement of the active compensation device is put forward. Finally, two devices have been installed in the power supply bureau of Guiyang. The operation of the active compensation device verifies the correctness of the theoretical analysis and experimental results.