High-power Energy Storage Flywheel Control And Its Application In Thermal Power Generation System

Flywheel energy storage is an efficient,fast and accurate physical energy storage method.It has significant advantages in frequency modulation and peaking of thermal power units.It can solve the problem of long response time and low adjustment efficiency of traditional thermal power units in peak and frequency modulation.It is not possible to fully track the AGC instructions and other issues.This paper mainly studies the charging and discharging control of flywheel energy storage system and the application of flywheel energy storage system in response to AGC commands of thermal power units,assisting thermal power units to respond quickly and tracking AGC commands in time,alleviating peak and frequency modulation pressure of thermal power units,and reducing thermal power units The number of responses increases the service life of the unit.First,a three-phase asynchronous motor was selected as the drive motor of the flywheel by comparison.Based on the vector control principle,the mathematical model of the asynchronous motor in the three-phase dynamic coordinate system and the two-phase rotating coordinate system was established,and the vector control method of the rotor flux orientation was selected.Determine the motor control strategy for the energy storage flywheel,and obtain the motor torque and rotor flux control law.Secondly,combined with the vector control mathematical model,in the Matlab/Simulink software,the motor side adopts m speed outer loop and current inner loop control strategies,and the grid side adopts the voltage outer loop and current inner loop control strategies,and establishes the motor side and grid side simulations respectively.Model,determine the relevant module parameters,and carry out the simulation verification of the charging and discharging process of the flywheel energy storage system.The results show that the control strategy has good control performance for the charging and discharging process of the flywheel energy storage system.Matching the motor side and the grid side with inverters,given the changing power signal,simulate the process of the flywheel energy storage system continuously switching charging and discharging working states in actual work,observing the speed,output power and other signals,the simulation results show that the energy storage The switching efficiency of the system during charging and discharging.Establish a charging and discharging protection module for the flywheel energy storage system to prevent charging or discharging when the speed is the highest or the lowest,and to protect the flywheel energy storage system.Finally,the AGC command signal and AGC performance indicators are analyzed,and a mathematical model of the thermal power unit’s power response is established.Combining the characteristics of the energy storage flywheel,the AGC command is decomposed,and the active power of the thermal power model and the active power of the energy storage flywheel are obtained respectively.The sum of the two is the power response of the thermal power unit with the energy storage flywheel system.Compared with the response,the energy storage flywheel can speed up the response speed of the fire storage system to AGC commands,effectively reduce the response frequency of thermal power,and increase the service life of the unit.