Research On The Wireless Monitoring System Of Air Source Heat Pump Water Heater Unit

Air energy is a new type of energy. At present, many electronics manufacturers have developed a series of products of air-source heat pump water heater units to meet the demand of plenty of hot water for public places such as hotels and schools. But a unit is often composed of one host and multiple slave machines. Due to large quantities and big ground occupation area, the units are usually installed on the roof, which brings operators inconvenience to detect and maintain. Meanwhile, the temperature setting of water and the start-stop control of defrost operation is usually artificially. It is necessary to further improve their control precision, intelligence level and maintainability. Motivated by above discussions, this thesis researches and designs a wireless intelligent monitoring system of air-source heat pump water heaters unit. The main work includesFirstly, this thesis introduces the characteristics and current status of air-source heat pump water heater unit and the operation principle of air-source heat pump. We synthetically analyze various factors impacting property and consumed power of heat pump water heater. The results show that it can decrease Heating COP and increase power dissipation to reduce the evaporation temperature and improve the condensation temperature for a series of products of air-source heat pump water heaters. The results also show that the higher the ambient temperature is, the better the heating performance of the unit is. Also, the higher the return water temperature is, the worse the heating performance of the unit is.Secondly, to optimize heating performance of unit, fuzzy PID control method is proposed. To solve the control problem of outlet water temperature, improve the evaporation temperature, reduce the condensing temperature and set appropriate return water temperature. Choosing appropriate membership function and fuzzy rule, we establish fuzzy PID model based on LabVIEW. Simulation and live debug indicate that fuzzy PID control effectively solve the properties of large overshoot, long transition time and realize intelligent control to water temperature.Thirdly, we perform research and improvement on the communication mode between host and slave machines, design the main control panel outside unit and add Non-contact level measurement module. Through the above efforts, we realize real-time acquisition and transmission of state parameters such as outlet water temperature, tank level, electric current of compressor, frost temperature and environmental temperature.Finally, to solve the existing problems of real time observation and wire communication, we design a remote wireless communication method. In this scheme, we send each state parameter to remote upper computer to display, realizing wireless transmission by means of Wireless RF transceiver modules. Accordingly, we design a host computer interface based on LabVIEW to monitor the operating state of unit. And the integration level of the system is further improved by combing fuzzy PID control operation with wireless monitoring system. Live debug and tests indicate that the wireless remote monitoring system works well, and meet consumers′ needs.