基于晶闸管的配电变压器有载自动调压系统设计

On-load Automatic Voltage Regulation System with Thyristors for Distribution Transformer

配电网中各配电变压器分布较零散,使得电压调节困难,电压稳定性较差。为解决这一突出问题,提出并设计了一种能够自动对配电变压器输出电压进行调节的系统。该系统用晶闸管代替机械开关,结合嵌入式控制技术,以监测到的变压器二次侧电压为基准,通过切换高压侧分接绕组,在有载情况下自动对输出电压就地进行调节,以提高配网电压稳定性。此外,在对现有无触点有载分接开关的研究基础上,对调压电路拓扑结构进行了改进并设计了合闸保护方案,对电压检测及分接绕组切换算法进行了优化,从而有效降低了系统制造成本,且使系统运行更加可靠、稳定。现场测试验证了所设计样机的有效性。

Transformers in power distribution network are usually scattered, resulting in difficult voltage regulation and poor voltage stability. To solve this problem, a system which can automatically adjust the voltage output of the distribution transformer was designed in this study. In this technique, thyristors are substituted for mechanical switch, and the embedded control technology is employed to automatically adjust the output voltage in situ under load condition with the monitored transformer secondary voltage as the reference by way of switching the high-voltage side tap winding, hence the stability of the power distribution network can be enhanced. In addition, on the basis of the existing no-contact on-load tap-changer analysis, the regulator circuit topology was improved, a closing protection scheme was designed, and the voltage detection and winding switching algorithm was optimized. Thereby, the manufacturing cost of the system get lower, and the system becomes more reliable and stable. The prototype of the designed automatic voltage regulation system was tested to verify its effectiveness.