基于PSD-FDS的内蒙古电网中长期动态仿真分析

Mid-and-Long Term Dynamic Simulation of Inner Mongolia Power System Based on PSD-FDS

基于全过程动态仿真软件PSD-FDS,在内蒙古电网仿真数据中加入典型中长期模型,即火电厂锅炉及其调速器模型、发电机过励磁限制器(OEL)和有载调压变压器(OLTC)模型,分析其对系统稳定性的影响。仿真结果显示,加入锅炉及其调速器模型后,机组的机械输出功率跟随系统需求的能力减弱,更好地模拟了火力发电机组的出力特性;OEL正确动作虽达到了保护发电机的目的,但却使相关节点电压明显跌落;加入OLTC后,负荷侧端电压得到提高,但在无功功率储备较不充裕的区域,分接头动作会加重系统无功缺额。对此提出提高过励恢复系数及锅炉汽包存储时间常数、合理设置有载调压变压器参考电压、加装无功补偿装置等提高电网中长期电压稳定性的措施。

Based on the whole-process dynamic simulation software PSD-FDS,mid-and-long term is added to Inner Mongolia power grid simulation data,which includes the boiler and its control system,over-excitation limiter(OEL)and on-load tap changer(OLTC).The impact on system stability is analyzed.The simulation results show that after adding the boiler and its control model,the mechanical output power of the unit can weaken the ability of the unit mechanical power to follow the system demand,which better simulates the output characteristics of the thermal power generator.The correct action of OEL can protect the generator,but the relevant node voltage drops significantly.Adding OLTC increases the load-side voltage,but in the areas where the reactive power reserve is less abundant,the tap action will aggravate the reactive power shortage.Finally,this paper proposes measures to improve the mid-and-long term voltage stability,such as improving the overexciting recovery coefficient and boiler drum storage time constant,rationally setting the on-load tap changer voltage,and installing reactive power supplement devices,etc.