Distribution Transformers Arc Oltc Research

Voltage is one of the important targets to verify power quality. The higher desire for power supply quality and reliability has been advanced along with the rapid development of national economy and the continuing elevation of people's standard of living. Voltage excursion in electric power system can been made by various causes, when it is severe, enormous losses and breakage will be brought to power equipments and power users as well as the system per se. On-load transformer can regulate voltage with load, and it is a effective means for voltage control. So on-load transformer has been gotten all-pervading application step by step in distribution networks in recent years. On-load tap changer made up of mechanical and dynamoelectric components is adopted in traditional on-load transformer. Its speed of voltage regulating is slow, and arc is produced easily, as well as its fault ratio is high all long. The function of on-load voltage regulation for transformer is then affected badly. The development of power electronic technology makes it possible to carry out tap shift by using microprocessor to control directly power electronic switch. The development trend in this field is that mechanical voltage regulation technology is replaced by quick and arc less power electronic voltage regulating technology.It was put forward that a new technology scheme of arcless on-load voltage regulation regarded power electronic switch as the key part in this paper, and this was based on investigating as well as summing-up and analysis to this technology over the world. The simulation model of the scheme was established using PSCAD/EMTDC (Electro Magnetic Transients for DC). Simulation study and analysis for the shift and transition of power electronic switches was carried through, and the feasibility of this scheme was validated primarily.The final realization of arcless on-load voltage regulating scheme depends on the reliable and effective control of its auto control system. The correlative interference and technical countermeasures for SCM measure and control system were analyzed and studied, and a control device with Cygnal mixed beacon age CMOS chip C8051F SCM (Single Chip Micyoco) of arcless on-load voltage regulation was set up. The hardware structure and function circuit design and the software flow design of control system were carried through.Finally, Low voltage test model of arcless on-load voltage regulating scheme was established with the new technology scheme of arcless on-load voltage regulation and the design of control system. Simulating voltage excursion instance in...