| Voltage is an important index of power quality and maintaining normal voltagelevel is an important guarantee to power system economic operation. Grid operatingvoltage level and reactive power is closely related. If the balance relationship betweenreactive power supply and reactive load is broken, it will lead to voltage changes andseverely affects power system safe operation. Rational regulation of reactive powersupply is an important measure to guarantee normal voltage level. Synchronousgenerators as important reactive power supply of power system have importantinfluence to the network voltage level. Excitation system voltage adjustment is animportant parameter to describe the external characteristic of synchronous generatorsvoltage and reactive power. Excitation system voltage adjustment is not only hasimportant influence on the synchronous generators voltage and reactive power, butalso on the network voltage level. Therefore, subset selection for improving thevoltage level of power system is problem crying for solve.In this paper, the new node type of generator and a strategy is proposed to set theexcitation system adjustment coefficient of the generators and to improve the powersystem voltage level. The effect of excitation system adjustment coefficient on powersystem voltage is studied, and the principle for setting the generator excitation systemadjustment coefficient region by region is proposed. An optimization model isdeveloped with the voltage fluctuation index minimum as control variables. Theparticle swarm optimization(PSO) algorithm is used in finding the solution.The case studies of Jilin province power system show that the optimizationstrategy is meaningful in improving the quality of the power system operation voltageand the potential of generator reactive power regulation. |
