发电机励磁限制协调配合优化分析

Optimization Analysis of Generator Excitation Restriction Coordination

当前发电机励磁调节器普遍配置各种励磁限制功能,包括低励限制、V/f限制、过励限制等,各种限制功能对于提高电力系统动态、暂态稳定均有重要作用。该文针对某地区电网线路故障后孤网运行期间在低频低压状态下由于励磁低励限制与V/f限制配合失当,造成孤网电压始终偏低并进而造成孤网瓦解。基于此,提出针对地区电网运行时发电机励磁限制配置方案及参数优化,以使所配置的励磁限制参数满足地区电网运行方式多变特征。利用PSCAD/EMTDC电磁暂态仿真软件搭建含有风电场的地区电网模型,对所提出的励磁限制间协调控制进行分析计算,优化限制功能参数设置及其与PSS参数配合关系,算例计算结果表明所提出的励磁限制协调优化方法的正确性,同时不会导致系统阻尼弱化。

At present,generator excitation regulators are generally equipped with various excitation limiting functions,including low excitation limit,V/f limit,over-excitation limit,etc.Various limiting functions play an important role in improving power system dynamics and transient stability.It shows that under the low frequency and low voltage state of the isolated network,due to the mismatch between the excitation low excitation limit and the V/f limit,the isolated network voltage is caused.It is always low and causes the network to collapse.Based on this,the configuration scheme and parameter optimization of generator excitation limit for regional grid operation are proposed,so that the configured excitation limit parameters can meet the varied characteristics of regional grid operation mode.The PSCAD/EMTDC electromagnetic transient simulation software is used to build a regional power grid model with wind far ms.The proposed coordination control between excitation limits is analyzed and optimized,and the limit function parameters are optimized.The calculation results show that the proposed excitation limit coordination optimization method The correctness will not cause the system damping to weaken.