Power Generation Compensation System Of Micro Gas Turbine Based On Flywheel Energy Storage

Micro-gas turbine,as the main form of distributed energy equipment,has been widely concerned in modern times because of its small size,high efficiency,light weight and low emission.In recent years,the micro-gas turbine power generation system technology has been developing rapidly,which is widely used in power generation,ship,locomotive,industrial process,vehicle and other equipment.However,there is a problem of impact load in the industrial process,and the traditional microgas turbine power generation system cannot respond to the impact load quickly due to its characteristics of combustion delay.In order to adapt to some special applications and improve the quality of micro-gas turbine power generation,this paper proposes a new micro-gas turbine power generation system based on flywheel pure energy storage structure,aiming to improve the performance of micro-gas turbine power generation system.At first,the traditional micro-gas turbine power generation system is studied in this paper and the mathematical model of permanent magnet synchronous generator and PWM rectifier is established.The unit power factor control strategy is adopted to control the permanent magnet synchronous generator,and the PI regulator setting in the control system is adjusted to obtain good transient state and steady state response of the system.Based on the steady control of the dc bus voltage,the system efficiency is improved,meanwhile the influence of armature current on the magnetic field is also reduced.Step change is set on the load side to simulate the impact load condition,which is used to analyze the fluctuation of the dc bus voltage on the dc side of the micro-gas turbine power generation system in the face of the impact load problem.Secondly,the structure of flywheel energy storage system is built,which adopts the combination structure of flywheel,doubly-fed motor and PWM rectifier.The mathematical model of doubly-fed motor is constructed to control its active and reactive power.The response rate of a flywheel generator to the required power is analyzed in the face of changing rated power demand.The results show that the flywheel energy storage system has a fast response speed and can quickly reach the stable value of the system.Therefore,it can be well used in the occasion of micro-gas turbine power compensation.In the end,a new type of instantaneous power compensation power generation system is proposed to solve the problem of slow output power regulation rate of traditional micro-turbine generator system.The system can quickly compensate the power mismatch on the dc side and absorb the regenerative power to reach the power balance.This paper analyzes the energy flow and power flow loss of the new generation system structure,and studies the conversion of various energy as well as the improvement of conversion efficiency.By building the model of instantaneous power compensation controller,DC side load identification and output power prediction of permanent magnet synchronous generator were carried out for impact load.Then the flywheel compensation power is calculated,which is converted to active doubly-fed motor output power and passes to the doubly-fed motor to control itself,to realize a power balance of the new power generation system under the condition of the load step change.The power generation system model was built on the MATLAB-Simulink platform for simulation verification.Finally,it is proved that the new micro-gas turbine generation system can solve the problem of power mismatch well and effectively improve the power generation quality of micro-gas turbine under impact load.