The project belongs to the field of energy and environmental science. The development of new energy vehicles is an important engine for promoting sustainable economic and social development in our country. However, traditional electric air conditioners using thermistors (PTC) heating will reduce the cruising range by 50% in winter~60%, which restricts the promotion and application of electric vehicles in the northern region. Automotive heat pump technology uses the principle of reverse Carnot cycle to absorb heat from an air source instead of direct electricity consumption. It is the most effective technical means to improve heating energy efficiency and solve the problem of large attenuation of cruising range in winter. There are the following core technical bottlenecks in the application of automotive heat pump air conditioning systems: rapid degradation of low-temperature environmental performance and frequent frosting and defrosting, insufficient reliability and efficiency of heat pump compressors, and coupled control of energy conservation and comfort of complex mode systems. This project team has lasted for 10 years. With the support of several key industrialization projects in Shanghai City, it has carried out technical research around the automotive heat pump system architecture, electric scroll compressors and system intelligent control, and achieved the following results: 1. Invented a vehicle heat pump air conditioning architecture for efficient heating in ultra-low temperature environments: Developed quasi-two-stage compression and large-flow air supply independent control technology, indoor dual heat exchanger series technology, motor electronically controlled waste heat source energy recovery technology, plug-in and indirect outdoor microchannel heat exchanger anti-frosting technology to achieve The system has increased total flow, enhanced condenser heat exchange efficiency, improved heating energy efficiency, and reduced frosting frequency, allowing the system to operate stably and efficiently in a-20℃ environment, and increased heating energy efficiency (COP) from 1.0 to 2.2. The vehicle cruising range has increased by 25%. 2. Invented a wide temperature zone and wide speed electric scroll compressor for a vehicle heat pump: Developed variable pitch profile design and end correction compensation technology, dynamic and stationary scroll adaptive shaft radial flexibility system, 6-stage 9-slot concentrated winding motor design technology, and high-frequency injection sensorless motor control technology, overcome the heat pump operating conditions The technical difficulties such as easy fracture of aluminum alloy at the end of the scroll, wear failure of the scroll disk, and vibration reliability of mechanical components during the limit speed and the limit pressure ratio of the heat pump are achieved.~Reliable operation in the range of 8600 RPM), doubling the comprehensive operating life, and improving compressor heating energy efficiency by 5%~10%。3. Invented the artificial intelligent energy-saving control technology for vehicle heat pump systems: proposed the dual-stage guidance and intelligent flow control technology for vehicle electronic expansion valves, which solved the difficulties of flow fluctuations and valve reliability under severe working conditions of the heat pump; A neural network optimal control strategy based on subcooling in heating mode, a collaborative sensing vehicle heat pump system control assembly, and a calibration technology based on sensitivity analysis have been developed to realize coupled control of the vehicle heat pump system that takes into account comfort and energy conservation. The system cycle has been expanded from single cooling mode to more than 6 working modes (heating, defrosting, low-temperature air supply, etc.), and the total calibration period of the vehicle heat pump system has been shortened by 50%. The project has obtained a total of 58 national invention patent authorizations, 7 software copyrights, and 75 papers have been published. Successfully developed the first ultra-low-temperature vehicle heat pump air conditioning system with independent intellectual property rights in China, developed more than 70 series of products, and took the lead in realizing industrialization in the field of new energy buses. In Jialeng Songzhi, Zhengzhou Kelin, Haili New Energy, etc. The company has implemented the transformation of results, with an added output value of 4.454 billion yuan in the past three years, a profit of 847 million yuan, and a tax revenue of 257 million yuan. The market share of electric bus air conditioning exceeds 60%. The products and technologies developed have been applied in more than 20 leading new energy vehicle companies such as BYD Bus, Yutong Bus, and Jianghuai Passenger Car. China Refrigeration and Air Conditioning Industry Association organized the appraisal of the project's research results reaching the international advanced level, the Ministry of Science and Technology organized the appraisal of JLD electric bus air conditioners as a national key new product, and the Shanghai Industry-University-Research Award Committee selected energy-saving bus air conditioners as the first prize for outstanding industry-university-research project.