交流励磁抽水蓄能机组运行功率能力计算

CALCULATION OF OPERATION POWER ABILITY FOR ADJUSTABLE SPEED PUMPED STORAGE UNIT WITH AC-EXCITATION MACHINE

具有交流励磁电机变速、功率解耦优点的抽水蓄能机组将在电力系统调峰、调频中发挥更好的作用,有必要研究考虑水头、流量和机组运行工况等约束条件下的可调速抽水蓄能机组运行功率能力的计算方法。首先,基于交流励磁电机电磁等效电路,考虑定、转子侧功率,推导发电和电动运行工况下的交流励磁电机接入电网侧的功率表达式;其次,考虑发电和抽水工况下水泵水轮机的工作特性,推导以水头和转速为变量的抽水蓄能机组的机械功率表达式,从而提出电动和发电工况下交流励磁抽水蓄能机组运行功率极限的计算方法和流程;最后,以某实际抽水蓄能机组参数为例,分析不同水头和转速下机组运行功率范围,并通过时域仿真结果验证所提计算方法的有效性。

Based on the advantages of adjustable speed and power decoupling of AC-excitation machine,the pumped storage unit are playing a better role in the peak shaving and the frequency adjustment in electric power system,and so it is necessary to study calculation method of operational power ability for adjustable speed pumped storage unit considering its impact factors including the water head,the flow rate and the operational condition.First,the power ability expressions of AC-excitation machine in generating and motoring are derived by using the electromagnetic equivalent circuit.Then,based on the working characteristics of pump-turbine units and pumping conditions,the mechanical power expression is presented with the water head and speed as variables,so that the operational power ability calculation method can be derived for the pump storage units using AC-excitation machine.Finally,taking the actual parameters of the pumped storage unit as an example,the operation power ability is analyzed with different water heads and speeds and the power decoupling operation is simulated.The results show that the presented operation power ability calculation method is valid.