Self-starting control strategy of variable speed pumped storage unit based on adaptive full order state observer

Abstract

When the variable speed pumped storage unit operates in the electrical state, the self-starting control strategy is generally used to start the process from zero speed to grid connection, which saves the starting device of the traditional constant speed unit and saves the construction cost of the unit. For the self-starting control process, the traditional open-loop flux calculation method will produce cumulative errors in the amplitude and angle of the flux when the motor parameters change. To solve this problem, an adaptive full order state observer is designed to observe the motor stator flux, which has stronger parameter robustness. Based on the flux observation, the speed adaptive law is designed to estimate the rotor speed and position angle, and the speed sensorless vector control of variable speed pumped storage unit is accomplished. The simulation results show that compared with the open-loop flux calculation method, the full order state observer can greatly reduce the flux estimation error and accurately estimate the rotor speed and position angle.