Electric Control System Design And Research Of Carbon Dioxide Heat Pump

With the improvement of people's quality of life requirements,especially in the demand for heating and hot water supply,traditional heating methods like coal burning or direct electric heating have been unable to meet people's needs,and have drawbacks of unfriendly environment and low efficiency.Carbon dioxide?CO₂?heat pump uses CO₂ as the refrigerant,its efficiency was several times that of the heat pump that use other refrigerants because of unique working principle,so there was no pollution to the environment.It will have far-reaching implications for solving energy and environmental problems.The task of this project was to design a carbon dioxide heat pump electronic control system.In this paper,the core component of the heat pump—DC inverter compressor and its drive system was simulated by Simulink tools,the main controller of the heat pump with STM32 MCU as the core was designed,the EMI filter and protection for input power was designed and explained,the auxiliary power supply in the variable frequency driver,the three-phase IGBT module circuit and its drive circuit,the voltage and current measurement circuit was designed and analyzed,the temperature and pressure data acquisition circuit,electronic expansion valve and relay drive circuit,PWM output and digital I/O interface,and communication interface circuit in the main controller was designed and analyzed.In the software design,all the various underlying drivers,control algorithms and control logic are written by C language.The paper is mainly about the research and design of the electric control system in the heat pump.Under the control of the main controller,the heat pump system operates safely,efficiently and continuously according to specific control logic.Experiments show that in the actual case of considering the efficiency of motor,compressor and heat exchanger,the coefficient of performance?COP?of carbon dioxide heat pump can reach above 2.2,and the outlet water temperature can be maintained at a higher temperature above 55°C.