Development Of Semiconductor Thermoelectric Generator Based On STM32

In order to solve the problem of the recycle of industrial waste heat and respond to the national appeal forconserving energy and reducing emissions,the semiconductor thermoelectric generatoris developed on the basis of thermoelectric effect in this thesis and it can be realized under laboratory conditions,achieving the goal of thermoelectric power generation and the presentation function.The main work of this paper can be summarized as the following aspects:(1)Design and Research on the overall scheme of semiconductor thermoelectric generator.According to the basic principle of thermoelectric power generation, the ideal model of semiconductor thermoelectric generator is set up.And the expression of the output characteristic of thermoelectric generator is derived by using the theory of thermodynamics. On the basis of qualitative analysis of the main factors that affect the output performance of thermoelectric generator,the structure and working mechanism of the semiconductor thermoelectric generator are analyzed, especially the core of the control system of semiconductor thermoelectric device.. According to the overall design principles of the instrument and the new requirements of the project, the overall design scheme is given from the perspective of maintainability, aesthetics and the following promotion. STM32F103C8T6 is used as the main control unit.And the hardware circuit control module is made of voltage and current detection circuit, A/D conversion circuit, temperature control circuit, man-machine interaction module and temperature acquisition unit.The design of the overall scheme of the thermoelectric generator is completed by combining with PID control algorithm and the PC statistical algorithm.(2) Research and implementation of the hardware design of semiconductor thermoelectric generator.The hardware design of the device’s control system is put forward on the basis of key module of the thermoelectric generator’s control system. The specific circuit is establishedbased on the function of hardware circuit of each module.The output voltage of the thermoelectric power generation module is entered to ADC of the main control chipthrough an amplifying filter clamp circuit. Then the transformation results are introduced into the PID operationso as to control the power module’s heating time and achieve the purpose of temperature control.The load circuit is drived by stable output voltage finally.The temperature acquisition unit works as the auxiliary control function.And all datacollectedis sent to the upper computer through the Serial to USB circuit.(3)Research and implementation of the software design scheme of semiconductor thermoelectric generator.The software design of Semiconductor thermoelectric generator’s control systemis the key link of the development of the instrument. The software is mainly composed of the upper computer and the lower computer. The upper computer software is written by C#language,which is responsible for serial data acquisitionand achieves the functions of unpack data, data storage, data analysis and graph drawing. The software of singlechip processor is programmed by C language,which mainly accomplishsthe functions of the acquisition of temperature, voltage conversion, simple human-computer interaction, the heating temperature control, control the load control and so on.And All data is sent to the upper computer through USB serial port.The singlechip processor sendsthe collected data to the upper computer software swiftly and efficiently,and the ADC sampling is optimized to make the sampling and conversion parallel.The DMA in the main control chip is utilized to preform PWM transformation to eliminatethe intervention of ALU in order to improve the transmission efficiency.(4)Research and implementation ofthe design scheme of the test platform of semiconductor thermoelectric generator.According to the basic heat flux method of thermodynamic,the vertical distribution of thermoelectric power generatoris determined so as to provide a vertical flow channel for heat transfer conveniently.The testing platform of semiconductor thermoelectric generator is set up on the basis of design principles such as good appearance and reasonable structure design.Heat source is simulated in the laboratory.The DJR-G type silicon rubber heater is used as the heating device,the fin radiator is employed as the cooling device and the heat insulation layer is combioned.Thetesting platform of semiconductor thermoelectric generatoris formed.(5) Implementationof the output characteristic test of semiconductor thermoelectric generator.The semiconductor thermoelectric generator is applied tostudy and analyse the power generation characteristics of the module.The load resistance has a complicated influence on the thermoelectric power generation device. With the increase of the load resistance, the output power increases first and then decreases, and the maximum value is achieved when the matching resistance is reached.The cold end of the thermoelectric module has great effect on the output power.And the output power is different if the various cooling modes are adopted.Effective cooling strategies are taken to increase the output power.The successful implementation of the project provides a good platform for talents cultivation and the further application of semiconductor thermoelectric generator,and finds a new way for the recovery of industrial low-grade waste heat.