Research Of Double Variable Frequency Control System Of Air Conditioning Based PMV In Pure Electric Buses

With the development of China’s economy and the continuous progress of society,traffic has become more and more convenient,but the following problems are increasingly serious,such as environmental pollution,energy depletion,road congestion.These sounded the alarm for the sustainable development of human life and society.Therefore,governments strongly urge sustainable development measures and advocate people to choose buses,subways and other means of transportation as much as possible to ease traffic congestion and exhaust emissions.As the representative of the new energy vehicle,pure electric buses are an important breakthrough to realize sustainable development and environmental protection.Air conditioning is the main adjustment tool of bus compartment environment,how to make the air conditioning to reach the human comfort level and reduce the energy consumption have become an urgent problem to be solved.This paper has done some research on thermal comfort prediction modeling of the electric indoor environment and double variable frequency control system of air conditioning,the main contents are as follows:(1)The research on modeling of air conditioning control system.From the perspective of energy saving,the structure and working principle of air conditioning system about pure electric bus are studied,air conditioning system with more energy consumption is improved,the energy conversion of the compressor and the fan are analyzed and the mathematical model of double variable frequency control system is established.This lays a good foundation for the simulation and hardware design and implementation of double variable frequency air conditioning control system.(2)The research on thermal comfort prediction model in pure electric bus environment.The thermal comfort index PMV(Predicted Mean Vote)is as control target of air-conditioning control system in bus,the thermal comfort intelligent prediction model is established based on the nonlinear and complex problems in the calculation process of PMV.According to the characteristics of small sample data in this paper,SVM(Support Vector Machine)regression prediction algorithm is adopted,a prediction model based on improved PSO(Particle Swarm Optimization)algorithm to optimize SVM parameters was proposed.Three kind of prediction algorithms for thermal comfort index PMV are compared,such as BP(Back Propagation)neural network,BP neural network based on improved PSO and SVM based on improved PSO.By comparing and analyzing the simulation results to prove the validity of the prediction algorithm.(3)The research on thermal comfort index PMV control system in air conditioning.The temperature and wind speed are as control variables of system,the thermal environment in pure electric bus is adjusted by thermal comfort PMV directly control.AGA(Adaptive Genetic Algorithm)is optimized the traditional fuzzy control algorithm and a thermal comfort index PMV fuzzy control system based on AGA is established.The fuzzy control algorithm based on AGA and the traditional fuzzy control algorithm are compared to prove the validity of the algorithm and the rationality of the control system.(4)Design and implementation of double variable frequency air conditioning control system in pure electric bus.According to the specific functions of double variable frequency air conditioning,the hardware circuit of the core controller,the embedded control system,is designed.According to the control objectives in bus,the fuzzy control algorithm is as the core part of the software design,the fuzzy control rules about the working frequency of the compressor and fan speed are designed.Through the performance analysis,the air conditioning control system are carried out to prove the effectiveness in practical application.