大容量辅机启动对孤立电网电压影响仿真

Simulation for effect of large capacity auxiliary machine start-up on isolated power grid voltage

针对电网孤立运行条件下大容量辅机直接启动造成电网电压大幅下降的问题,基于辅机启动的基本原理以及孤立电网网架结构,建立了相应地区电网的电磁暂态仿真模型,并提出可行的孤立电网辅机启动策略.对电厂辅机的启动特性、辅机启动对电网电压的影响以及动态无功补偿装置在辅机启动过程中的补偿特性进行了仿真计算与分析,仿真结果表明,大容量辅机启动虽未造成电网失稳,但给电网电压带来很大冲击,而该启动策略可以有效地抑制冲击,为孤立电网的安全稳定运行提供了理论依据和可行性建议.

In order to solve the substantial decrease problem of power grid voltage caused by large capacity auxiliary machine direct start-up under the isolated power grid operating condition, an electromagnetic transient simulation model for the power grid in the related region was established based on the basic principles of auxiliary machine start-up and the power grid frame of isolated power grid, and the strategy for the auxiliary machine start-up of isolated power grid was proposed. In addition, the set-up characteristics of auxiliary machine in the power plant, the influence of auxiliary machine start-up on the power grid voltage and the compensation characteristics of dynamic reactive power compensation devices in the auxiliary machine start-up process were simulated and analyzed. The simulated results show that the large capacity auxiliary machine start-up will not cause the power grid instability, but imposes the great impact on the power grid voltage. However, the proposed start-up strategy can effectively suppress the impact, and provide both theoretical foundation and feasible suggestions for the safe and stable operation of isolated power grid.