基于晶闸管的自动调压变压器故障诊断技术

Fault diagnosis technology of automatic voltage regulating transformer based on thyristor

[目的]船用设备的供电电压经常发生波动,现有的稳压方案经济效益和可靠性低,亟待研发适用于恶劣工作环境的自动配电设备。[方法]设计基于双向晶闸管与调压变压器的三相串联调压装置,通过控制双向晶闸管组件的投切方式,即可调节电压的幅值及方向。针对该调压装置的3种故障模态,分析其故障诊断方法和处理方案,并开展仿真验证实验。[结果]结果表明:该设计可以仅参考输入电压进行双向晶闸管组件投切,从而实现输出电压的调节、稳定功能。当晶闸管组件的H桥发生断路故障时,仅对装置的调压效果产生影响;当变压器高压侧的短路晶闸管发生断路故障时,将可能在变压器高压侧感应出大电压或在低压侧产生冲击大电流,进而对装置造成损害;当晶闸管组件发生短路故障时,若等效为变压器不补偿工作,对装置没有影响;而若等效为变压器短路运行,将可能在整个回路中产生冲击大电流,进而危害装置和用电设备。[结论]该设计方案将调压变压器直接串入供电回路之中,故其调压反馈效果较为显著;采用性价比更高的双向晶闸管作为交流开关,并采用所提出的故障诊断技术,可有效提升调压变压器的可靠性和使用寿命。

[Objectives]The voltage of marine electrical equipment often fluctuates, but the existing stabilization schemes have low reliability and high cost. As such, distribution equipment that can operate in harsh environments is required to stabilize the voltage.[Methods]This paper puts forward the design for a threephase series voltage regulator based on a bidirectional thyristor and voltage regulator. It functions by controlling the magnitude and direction of voltage regulation through switching the bidirectional thyristor. Furthermore, the fault modes of the thyristor are analyzed and its fault diagnosis scheme obtained.[Results]The results show that this design can realize the stabilization of only the output voltage by switching the bidirectional thyristor only according to the input voltage. when the H-bridge of the thyristor assembly breaks, it only affects the voltage regulation effects of the device. When the short-circuit thyristor of the high-voltage side of the transformer has an open-circuit fault, a large voltage or a large impact current is generated on its low voltage side, causing damage to the device. When the thyristor component has a short-circuit fault, if the equivalent is that the transformer does not compensate for the work, it has no effect on the device. If the equivalent is the short-circuit operation of the transformer, a large impact current may be generated in the entire circuit, causing damage to the device and electrical equipment.[ Conclusions] The voltage-regulating effects of this design are significant because it directly integrates the voltage-regulating transformer into the power supply circuit. With the more cost-effective bidirectional thyristor as an AC switch and the designed fault diagnosis technology, the reliability and service life of voltage regulating transformers can be improved.