The Research For Intelligent Control Of Constant Temperature On Heat Pump

The intelligent heat pump technology with the feature of energy-saving and environmental protection is becoming the direction of the water heater in the future. As the core part of the heat pump water heater, the majority of the constant temperature control system have to manually adjust the water temperature, but the temperature is not stable and have large overshoot. In order to promote the constant temperature control system is under development towards intelligent, integrated and stabilization, the paper proposed an intelligent constant temperature regulating system which based on DSP and STM32 provides a perfect solution for the temperature control. These two parts collaborate with each other and play their greatest advantages.Because the water heater set in the outdoor, and the operation of the user in the room, so the paper determines the design scheme is master-slave mode which is made up with the control unit and the setting-display unit. The two units transfer the data by Zig Bee which is a wireless communication. The control unit with DSP as CPU, is mainly responsible for the acquisition signal, and then processing the signal data, in which embedded control algorithm, is a control algorithm platform; The setting-display unit with STM32 as CPU, is mainly responsible for reading and displaying data, as well as the users could input the parameters about the system, which is the displaying and operating platform in the air source heat pump water heater.In hardware design part, this paper completed the system power supply module, DSP system design, STM32 system design, signal acquisition module, signal output module, step motor drive circuit module, ethernet communication module, design of communication module and touch screen display.In software part, based on the analysis of the software function demand on the constant temperature control system of air source heat pump water heater, the whole software control flow of the constant temperature control and complex intelligent control algorithm are designed. And it is achieved by experiment platform. In the part of control algorithm, study out the complex intelligent control algorithm which suitable for the constant temperature control system. This control algorithm is on the basis of traditional incremental PID algorithm is optimized by intelligent PID algorithm, joined the augmentation with the first valve close technology, temperature slope control technology and valve tracking technology to form the complex intelligent control algorithm.In the last part of this paper, the constant temperature control system has been tested and verified overall. We verified the feasibility of the constant temperature control system through the heat pump water heater and achieve the goal that fast response speed, high precision of temperature and reached the desired performance indicators.