毕业论文（设计）基于单片机的直流电子负载设计（硬件）.doc

基于单片机的直流电子负载设计(硬件)

摘要:电子负载的原理是控制内功率MOSFET或晶体管的导通量,靠功率管的耗散功率消耗电能的设备,它的基本工作方式有恒压、恒流、恒阻、恒功率这几种。
本设计从直流电子负载系统方案分析入手,详细讨论了整个系统的硬件电路和软件实现,并给出较为合理的解决方案。论述了直流电子负载的设计思路和过程。为便于控制的实现和功能的扩展,采用了STC89C52单片机作为核心控制器,可实现以下功能:电子负载有恒压和恒流两种模式,可手动切换。恒压模式时,电子负载端电压保持恒定,且可设定,流入电子负载的电流随被测直流电源的电压变化而变化。恒流方式时不论输入电压如何变化(在一定范围内),流过该电子负载的电流恒定,且电流值可设定。A/D模块接受电路电压和电流模拟信号,转化为数字信号,经液晶模块同步显示电压电流。设计了D/A输出控制电路、A/D电压电流检测电路、键盘电路、显示电路和驱动电路,通过软、硬件的协调配合,实现了整个设计;能够检测被测电源的电流值,电压值;各个参数都能直观的在数码管上显示。
关键词:电子负载,恒压,恒流,单片机
指导老师签名:
Design based on MCU DC electronic load(Hardware)
Student name: Zhang Lianqi Class:1082022
Supervisor: Qiu Yulan
Abstract: The principle of electronic load is control of transistors inside power MOSFET or the guide flux of power tube, it is a consumption power equipment which depends on the dissipation power of tube, there are four basic working ways that persistence pressure, constant current, the constant resistance, constant power .
This design start with the analysis of DC electric load system solutions, it discussed the realization of the whole system hardware circuit and software in detail, and give a reasonable solution. Discusses the design idea and process of DC electronic load. In order to realize the control and the expansion of function conveniently, we adopted the STC89C52 microcontroller as the core controller, Can achieve the following functions: Electronic load with constant voltage and constant current two modes, you can manually switch . Constant voltage mode, the electronic load voltage is kept constant, which can be set, into the electronic load current with voltage variation of the measured DC power supply and change. No matter how the change in input voltageconstant current mode (in a certain range), constant current through the electronic load current, and the current value can be set. The A/D module receives the circuit voltage and current analog signal into digital signal, LCD module, the synchronous display of voltage and current. The D/A output cont