Large-scale pumped storage units are frequently started,and the working conditions are changeable.The protection adopts the auxiliary switch contacts of the electrical primary equipment and the contact signals output by the control system to identify the working conditions,and reasonably configures the protection according to the operating conditions and automatically switches on and off.In the low-frequency start-up stage,the frequency of the voltage and current signals is extremely low,the amplitude is small and the fluctuation is large.The conventional Fourier algorithm is used,and the error cannot meet the protection operation requirements.This paper analyzes the disadvantages of using fast frequency tracking to adjust the sampling interval,and proposes a protection adaptive algorithm based on asynchronous sampling data.By using the second-order low-pass filtering and frequency-independent RMS algorithm,the correctness of the algorithm is verified by simulation.The protection device using this algorithm has been applied in many pumped storage projects in China,and the equipment is running well.
关键词
大型抽水蓄能机组/启动工况/异步采样数据/自适应算法
Key words
large pumped storage unit/start condition/asynchronous sampling data/adaptive algorithm
维普
万方数据