Comparative Study Of Reactive Power Compensation Methods On Power System

In the electrical power system, there is lot of wattless load congenitally. The wattless load is caused by power circuit, power transformer and electrical equipments of user, these devices work properly, the system need to provide reactive power, used to establish and maintain the necessary magnetic field. When system works there is lot of wattless power caused, and the power factor of system will be lower. Circuit Voltage Loss and energy loss will be increased, it affacts the economic benefit of power enterprise strongly. Wattless power compensation is the method to solve these problems.The commonly used methods of wattless power compensation in power system were, transformer substation concentration compensation method, transformer low voltage busbar compensation method, circuit distribution compensation method and user disperse compensation method. Transformer substation concentration compensation aims at wattless balance of power transmission, its main purpose is to improve the power factor of transmission network, enhance voltage of terminal transformer substation and compensate the wattless loss of main transformer. Transformer low voltage busbar compensation method aims at enhancing power factor of special transformer user, it can help to decrease the loss of transmission circuit and the loss of transformer, and enhance the voltage quality and stabilize voltage level for the related user. Circuit distribution compensation method aims at compensating the wattless shortage of public transformer to enhance the power factor of transmission network and then decrease loss and improve voltage. User disperse compensation method aims at compensating the needs of terminal user who has electronical equipment such as electromotor, improving the voltage quality of electronical equipment. Use of reactive compensation equipment:power capacitors, synchronous condenser, SVC, STATCOM, etc, power capacitors which can only provide static reactive power, synchronous condenser, SVC and STATCOM can provide dynamic reactive power. Chapter three obtained by comparing the sum to control the voltage characteristics, the preferred choice SVC and SVG and the synchronous condenser; and for the cost saving, tend to choose the power capacitors.Since transformer substation concentration compensation method can only decrease loss of main transformer and loss of circuit of transformer substation or above, it cannot decrease loss of transmission network. But this method help the wattless power flow control greatly, it should be used together with other few compensation methods. Therefore, in this essay, it explains five sets of wattless compensation solutions, that is transformer substation concentration compensation method combineds to circuit distribution compensation method, transformer substation concentration compensation method combines to user disperse compensation method, transformer substation concentration compensation method combines to circuit distribution compensation method and user disperse compensation method, transformer substation concentration compensation method combines to transformer low voltage busbar compensation method and user disperse compensation method, transformer substation concentration compensation method combines to transformer low voltage busbar compensation method, ircuit distribution compensation method and user disperse compensation method. To compare the voltage index, loss reduction index, economic index obtained by these five solutions, it shows that the method of transformer substation concentration compensation method combining to transformer low voltage busbar compensation method and user disperse compensation method is better than other solutions.