Low voltage reactive power compensation module and networking expansion of system capacity

TAO Hai-jun， CHEN Guo-zhu
（College of Electrical Engineering， Zhejiang University， Hangzhou 310027， China）

Abstract： Aiming at solving the problems that the traditional reactive power compensation device is complicated in structure，inconvenient in wiring，lack of agility，and meet the user's demand of easy-using，the components of the traditional reactive power compensation device were integrated together to form the low voltage reactive power compensation module. In the design，module size and operational reliability were taken into consideration. In order to enlarge the compensation capacity easily，several modules were used to form a networking system and RS485 communication technology was applied to realize the communication and harmonized operation of the modules in the system. In the operation of the system，a master module was produced automatically to control the operation of the rest modules which were called slave modules and the master module can detect all the existing slave modules in the system. In case of breakdown of the master module such as communication failure，a new master module was produced to manage the normal operation of the system and enhance the system stability. The compensation method is suitable for both three-phase compensation module and split-phase compensation module and the module number in the system can reach to as many as 32. Thus the networking system fits for the compensation of imbalanced loads and the compensation capacity is enlarged significantly. The networking system has been taken into practical using and the operation status indicates stability，feature of easy-using，good compensation performance of the system and the system can meet the demand of the users well.
Key words： low voltage reactive power compensation； modularization； RS485； network expansion operation