Simulation And Energy Management Optimization Of Hybrid Power Gas Engine Heat Pump Based On Continuously Variable Transmission

Transmission device has attracted much attention as the power transmission system affects the operation of gas engine and the energy conversion efficiency of the whole system in the study of hybrid power gas engine heat pump(HPGHP).Hence,stable and efficient transmission device has been a new direction to optimize HPGHP.In this paper,continuously variable transmission(CVT)is used instead of multistage transmission to connect drive system and heat pump system,and energy management control strategies which include drive system and heat pump system are studied.The main research contents are as follows:(1)HPGHP are classified based on the structure.The thermal efficiency of drive system is defined to measure the performance of the whole system to select the most suitable type.The result shows that the parallel type is better than other types.(2)The main components of HPGHP are modeled.In drive system,the models of gas engine and motor as well as battery packs are established.And the transmission ratio of CVT changes in the range of 0.95 to 4.8.In heat pump system,the models of compressor,evaporator,condenser,expansion valve are built,and the simulation platform is also established.(3)The logic threshold control strategy based on the maximal drive system efficiency(S2)is put forward.And the upper and lower bound of SOC and gas engine power of the economic zone are selected as the threshold values.The method to get optimal working curve of gas engine and motor are made.Related parameters are maintained on the simulation platform.Then,compared with HPGHP with multistage constant speed ratio based on logic threshold control strategy(S1).The result shows that the drive system efficiency of the studied system is 5.7%,3.3%,2.7%higher than that of S1 in mode C,mode D,mode E,respectively.(4)The instantaneous optimization strategy based on the minimal equivalent energy consumption(S3)is put forward.The equivalent factor and penalty function are introduced to correct the objective function.The process of the strategy is developed and the simulation platform is built.The switching rule of different mode is get,the related parameters are also maintained.(5)The two proposed strategies of HPGHP with CVT are compared with HPGHP with multistage constant speed ratio(S1)in terms of fuel-consumed rate,gas quantity and recovery heat capacity.The results show that the fuel-consumed rate of S3 is 2.6%,1.1%lower than S1 and S2,and S3 saves 32%,4%more gas quantity than S1 and S3,respectively.As to recovery heat capacity,S2 and S3 collect 11.5%,14.2%less than S1.