New Design Of Reactive Power Compensation Controller

Reactive power compensation is related to security and steady of the electric power system,and it is important to improve quality and saving in power quality. Based on the investigation of reactive power compensation controller which used widely in the current domestic electric power market,we analyze it's existing problem of precision, oscillation and the problem of the electronic components of capacitance compensation case are damaged sometimes in harmonic condition. In this paper,we mainly use the electrical energy measurement chip ATT7022B as the AD chip and use the MCU PIC18F4520 for reactive power compensation controll chip.The strategy of cosφcriterion of the compensator has changed to the mainly criterion of reactive power and auxiliary criterion of voltage and harmonic composite from the real-time data acquisition.It can avoids oscillation on the condition of light loading better.And put up the compensation mode points of ingle-phase compensation and three-phase compensation together, it's more reasonable of adjustment in the three-phase reactive unbalanced situation. At the same time take the mathod of zero-crossing triggering capacitance can avoid electrical components damage in capacitors circuit of under overweight harmonic better.The reactive power compensation controller carries out the function such as automatic sampling analysis of reactive power, regulating the reactive power automatically,giving protection in case of faults,etc. This paper designs and realizes comparatively integrate microcomputer controlled circuit and program. They include signal sampling circuit, man-machine interface circuit and control circuit, main chip interface circuit, zero-crossing triggering circuit,and communication circuit, etc. The device has power measurement precision ,the control method is rational and feasible, man-machine interface and friendly, system runs reliable,it has more advantage in control of speed, the rationality of the compensation capacitor and safety. Experimental results show that the design is up to specifications of interrelated industry in nation.The device can realize the function anticipated.