【作者】 赵慧；

【导师】 沈锦飞；

【作者基本信息】 江南大学 ， 电力电子与电力传动， 2012， 硕士

【摘要】 本文以三相合成数字化倍频感应加热电源为研究对象,介绍了感应加热电源的基本知识和国内外感应加热电源的发展历程。针对焊接、热处理等领域对高频化和大功率化的要求,本文以180KHz/300KW为高频感应加热电源技术指标,设计了一种新型的主电路拓扑结构系统,采用三个单相合成三相的二极管不控整流不加滤波直接加倍频式逆变电路,通过控制逆变器实现单位功率因数。综合脉冲密度调制(PDM)与移相调制(PSPWM),设计了分时-PDM&PSPWM新型控制策略,改变驱动信号的脉冲密度和移相角实现功率调节,并分析了其电路的工作原理,同时采用IGBT并联分时控制的思想,达到增加输出频率的目的。基于器件串并联扩容技术会带来电压电流分配不均的问题,为提高电源的功率,采用变压器初级并联次级串联的功率合成的思想。对主电路各元器件进行了精确计算与设计,并详细分析了以TMS320F2812DSP和高速芯片CPLD为核心的控制与保护电路,同时,搭建了180KHz/300kW的感应加热电源样机,编写了基于分时-PDM&PSPWM控制策略,应用DSP实现数字化功率控制及采样、保护等功能,CPLD实现数字锁相及分频控制,这种控制方式能实时、自动地跟踪负载谐振频率。在理论分析的基础上,通过PSPICE仿真软件对单相逆变器主电路等效结构和控制方法进行仿真分析,并给出了部分仿真波形。实验结果表明,该新型的电路拓扑及新型控制策略的可行性。更多还原

【Abstract】 This paper, based on three-phase synthesis digital frequency induction heating power supply as the research object, briefly introduced the development and the basic theory of the induction heating. For high-frequency and great-power requirements, this paper research on 180KHz/300KW high frequency induction heating power supply, using three single-phase synthesis of three-phase diode rectifier is not controlled directly without filtering plusharmonic-type inverter circuit, which is controlled to achieve the purpose of unit power factor.Based on the power modulation strategies analasys of PDM and PSPWM, Time-sharing-PDM&PSPWM is presented, and its working principle is analysised.This paper used IGBT in parallel time-control theory to add output frequence. In order to raise output power, Synthesis power chose the way of primary parallel and second series of transformer. Every part in main circuit is designed. And the control and protection circuit based on TMS320F2812DSP and high-speed chip CPLD is detailed analysised. Setting up a sample of 180KHz/300KW, the microcontroller DSP realized all digital power control, and CPLD realized digital phase-locked and frequency division control. This control method can in real time and automatically track the load resonant frequency. Based on the the theoretical analysis, giving simulation analysis and key waveforms for single-phase inverter main circuit equivalent structure and control methods by PSPICE simulation software. The experimental proves the new power regulating strategy available.更多还原