The Coordinated Control Of The Gas Network And The Power Grid In The Energy Internet

With the depletion of fossil fuels and increasingly serious environmental problems,the use of clean energy is becoming more and more widespread.A large number of intermittent distributed power supply is connected to the power grid,the intermittent distributed power supply has a great influence on the power quality of the power grid.In view of the rigid fluctuations of the power grid caused by this distributed power supply and the development of Combined Cooling Heating and Power,in this paper,a power generation system composed of natural gas pipe network and micro gas turbine is used to cut the peak and fill the val ey.The modeling simulation of the power generation system composed of natural gas pipe network and micro-gas turbine turns the rigid fluctuation of the power grid into the flexible fluctuation of natural gas pipe network.In the background of the intermittent distributed power supply to power grid,the research of micro-turbine and photovoltaic composite micro network is of great significance.The main contents of this paper are as follows:1)According to the mathematical model of each element in the joint simulation of natural gas pipe network and micro-gas turbine,the Simulink simulation model of each component of the pipeline,valve and micro gas turbine is constructed,and the algebraic ring problem of natural gas pipeline element in real time simulation is solved.Then the real-time simulation model of pipeline element is built.Based on Simulink simulation platform,through the joint simulation of gas pipeline network and the micro gas turbine.The influence of the change of gas net load on the output power of microgas turbine and the influence of the output power of micro gas turbine on the gas net were analyzed.2)According to the structure of natural gas-micro-turbine power generation system,the simulation of micro-turbine power generation system is carried out by dual PWM converter,and the control strategy of the rectifier model in the converter is controlled by the voltage current double loop,the inverter model is controlled by VF in isolated island operation mode and PQ control is adopted in parallel operation mode.The operation characteristics of natural gas-micro gas turbine power generation system are simulated based on isolated island operation mode.This chapter analyzes the influence of power grid load change on natural gas network.3)The operating characteristics of the photovoltaic system are investigated according to the structure and principles of photovoltaic power generation.Photovoltaic power generation system adopts two-stage structure.In the DC-DC link,the boost chopper and the maximum power tracking control are realized,and the maximum power tracking control adopts perturbation observation method.Through the simulation model of photovoltaic power generation system,the output characteristic curve of photovoltaic cel s was verified,and the influence of light intensity and temperature of photovoltaic array on output power of power generation system is analyzed.4)A hybrid micro network consisting of a photovoltaic power generation system and a natural gas-micro-gas turbine power generation system is simulated,the simulation of hybrid micro grid is simulated by using the universal real-time experimental platform(UREP),the simulation platform uses two industrial controls based on xPCtarget technology.One of them with large step simulation operation of natural gas pipeline network and on the Simulink simulation model,the other Simulink model,which USES small steps to simulate the power grid of photovoltaic power generation system.The power generation system consisting of natural gas and microgas turbine can be realized in real time to suppress the power grid fluctuation caused by photovoltaic power generation system to ensure the power quality of the grid.Through the joint simulation of the hybrid micro grid,the effect of the fluctuation of the natural gas-micro-gas turbine generation system is verified.The rigid fluctuation of the power grid is transformed into the flexible fluctuation of natural gas net.