Thermal Management Integration Trend Outlook
Thermal management is becoming more and more important to electric vehicles. As the system becomes increasingly complex, integrated and modular design ideas are gradually recognized by the industry. Correspondingly, integrated design reduces the versatility of modules. How to use them in different applications Achieving compatibility and reuse between vehicle models is a practical problem faced by many companies. At the same time, the complex requirements of the system and the high degree of integration of components require more intelligent control to ensure the safety and stable operation of the system. Further, with the The popularization of heat pump systems, waste heat recovery and new heat-creating technologies requires improving the comprehensive utilization efficiency of energy from the perspective of integrated energy management of multiple heat sources. What must be paid attention to is the use of environmentally friendly refrigerant thermal management systems. Due to the physical properties of the refrigerant and Due to the particularity of system work, there are new problems that need to be solved during integrated design.
1. Integrated module platform
The thermal management system of electric vehicles is becoming more and more complex, and the concept of integrated design has gradually become popular, and has rapidly transformed from local integration and regional integration to system integration. As the degree of module integration increases, its versatility becomes less and less. In order to improve The compatibility and reuse rate of integrated modules between different vehicle models requires the construction of an integrated module platform. According to the functional requirements and performance bandwidth of different vehicle models, different integrated modules should be developed with reference to certain design principles and evaluation indicators, while taking into account the Reuse of each component sub-part. In subsequent model development, the corresponding modules will be selected from the platform for matching according to specific function and performance requirements, thereby effectively reducing the development time of the entire vehicle.
2. Intelligent system control
With the integrated design of electric vehicle thermal management systems, the number of related control parameters and control targets is increasing, resulting in increasing control dimensions and difficulties. Relying on traditional distributed control not only greatly increases development costs, but also causes problems due to too long transmission paths. Low control accuracy and poor reliability make it difficult to achieve refined, high-energy-efficiency optimal control. In order to give full play to the advantages of integrated thermal management of the three subsystems of the passenger compartment, power battery and drive motor, so that each component can maximize its performance, An efficient and intelligent control system must be equipped to achieve fast, stable and accurate system response.
Three integrated control schemes for battery management systems are proposed, in which the cell sampling module, relay driving module and data storage module are kept inside the battery pack, while the remaining functions are moved to the outside, becoming the mainstream solution for current passenger cars. The electronic and electrical architecture and typical domain controllers analyze the development direction of the current automotive architecture. It is pointed out that the integration of domain controllers can effectively reduce the total parts volume and reduce the difficulty of overall layout, while also facilitating subsequent fault location and vehicle completion. Maintenance. The traditional discrete controller structure in electric vehicles is integrated into one controller for research, which reduces unnecessary middle layers. The quality is reduced by 26.6% and the cost is reduced by about 21.2%. The real-time communication performance is also improved. The degree of improvement.
Integrated energy management
In order to widen the operating temperature range of electric vehicles, especially to achieve better battery life retention at lower temperatures, the thermal management system needs to be able to provide more heat and higher quality heat sources. In addition to PTC electric heaters and the increasingly popular air In addition to source heat pump air conditioners, technologies such as motor waste heat recovery, jet enthalpy increasing system, and compressor triangular cycle heating are also becoming increasingly mature and are gradually being applied to mass-produced models. How to choose and switch according to needs among so many heat sources? Directly affects the comprehensive utilization efficiency of vehicle energy.
Take motor waste heat recovery as an example. When the motor temperature is too low, the heat quality of the motor waste heat is low, and the heat utilization efficiency recovered through the heat exchanger is low. When the motor temperature is too high, the heat exchange between the motor and the outside air will be enhanced. , so that most of the heat is dissipated, the amount of heat that can be recovered decreases, and it cannot be used efficiently. Similarly, air source heat pump air conditioning technology uses the vapor compression cycle to utilize low-grade heat in the environment, and the heat during heating is The theoretical COP is greater than 1;
As for the PTC electric heater heating and compressor triangle cycle heating technology, due to the heat exchange losses in the pipelines and heat exchangers in the system, the system heating efficiency is less than 1, and the thermal efficiency of the PTC and compressor also exists under different working conditions. Differences. Therefore, the characteristics of multiple heat sources are analyzed, and they are reasonably allocated according to factors such as ambient temperature, vehicle demand, system mode, heat exchange efficiency, etc., and the echelon utilization of energy is considered from the perspective of the entire vehicle, and the energy consumption and low temperature of the entire vehicle are Battery life is crucial.
