基于碳化硅器件小型化大功率高压电源的研究

发布时间：2018-01-19 18:24

本文关键词： 碳化硅MOSFET 高频开关小型化大功率高压电源　出处：《电子科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：高压电源是电力电子系统中的基本能量转换单元,在军事、科研、医疗、环境工程等方面表现得十分抢眼。它为高功率微波(HPM)源提供能量,尤其是以回旋管为代表的电真空器件需要它提供极高的电压和足够大的功率。而在应对非传统安全时,对高功率微波系统的可移动性和隐蔽性提出了苛刻的要求,因此在系统设计时,提高大功率高压电源的功率密度十分迫切。碳化硅(SiC)器件打破了硅(Si)器件的物理应用极限,使用它能够提高开关频率、减少损耗和简化复杂庞大的散热系统,可有效的实现高压电源的小型化。全文设计有效的利用了碳化硅绝缘栅型场效应管(MOSFET)和肖特基势垒二极管(SBD)的高频开关特性以及耐高温、耐高压和导通损耗小的物理特性。本文对高压电源的基本拓扑结构和馈电方式做了介绍,分析了串并联谐振充电(LCC)技术,对谐振参数的计算公式做了详细的推导,并提出了简易、精确的计算方法。本文重点解决了一个主要矛盾:提高开关频率时,谐振电感电容乘积小而输出功率却很大、升压很高。由于开关频率过高,变压器升压困难、高频损耗很大,并且绝缘处理棘手,导致变压器漏感和高压分布参数的乘积很大,限制了谐振电路的正常工作,以致单个模块的输出有限。所以着重针对大功率高压高频电源的升压结构和高压模块的组合进行了分析和设计,有效的降低了谐振电感电容的乘积,实现了功率容量的扩展和系统工程的集成。在提高开关频率时还要解决后继问题:高压高频变压器及整流器的封装、高频整流和大功率MOSFET的快速驱动。而高频整流不同于传统的高压硅堆整流,需要考虑高压分布参数和绝缘的影响,本文用SiC-SBD的串联来替换了高压硅堆整流器,并考虑了高压二极管串联的均压问题。在进行电气设计和高电压试验时,要保证设计的合理性和安全性,因此本文分析和总结了大量的工程实践经验,包括:高电压分布参数的处理和测试、高电压接地技术和安全放电、快速驱动和保护电路设计、热设计和绝缘处理、以及电磁兼容分析和负载测试。最后分别计算、仿真和对比了全碳化硅开关高压电源和传统高压电源。
[Abstract]:High voltage power supply is the basic energy conversion unit in power electronic system, which is very attractive in military, scientific research, medical treatment, environmental engineering and so on. It provides energy for high power microwave / HPM-based power source. Especially the electrical vacuum device represented by gyrotron needs it to provide extremely high voltage and enough power. The mobility and concealment of the high power microwave system are demanding, so in the design of the system. It is very urgent to improve the power density of high power high voltage power supply. Sic device has broken the physical application limit of SiC device, and the switching frequency can be increased by using it. Reduce wastage and simplify complex and large heat dissipation systems. It can realize the miniaturization of high voltage power supply effectively. The full design makes use of silicon carbide insulated gate FET (MOSFET) and Schottky barrier diode (SBD). High frequency switching characteristics and high temperature resistance. In this paper, the basic topology and feed mode of high voltage power supply are introduced, and the series-parallel resonant charging technology is analyzed. The formula of resonant parameters is deduced in detail, and a simple and accurate calculation method is put forward. This paper focuses on solving a major contradiction: increasing the switching frequency. The resonant inductance capacitance product is small, but the output power is very big, the boost voltage is very high, because the switching frequency is too high, the transformer boost voltage is difficult, the high frequency loss is very big, and the insulation processing is difficult. As a result, the product of leakage inductance and high voltage distribution parameters of transformer is very large, which limits the normal operation of resonant circuit. As a result, the output of a single module is limited. Therefore, the combination of the high-power high-voltage high-frequency power supply and the high-voltage module is analyzed and designed, which effectively reduces the product of the resonant inductance capacitance. It realizes the expansion of power capacity and the integration of system engineering. It also solves the following problems when increasing the switching frequency: the packaging of high-voltage high-frequency transformer and rectifier. The high frequency rectifier is different from the traditional high voltage silicon stack rectifier, and the influence of high voltage distribution parameters and insulation should be considered. In this paper, the SiC-SBD series is used to replace the high voltage silicon stack rectifier, and the voltage equalization problem of the high voltage diode in series is considered. The electrical design and high voltage test are carried out. To ensure the rationality and safety of the design, this paper analyzes and summarizes a large number of engineering experience, including: processing and testing of high voltage distribution parameters, high voltage grounding technology and safe discharge. Fast drive and protection circuit design, thermal design and insulation treatment, electromagnetic compatibility analysis and load test. Finally, the calculation, simulation and comparison of the full carbide switch high voltage power supply and the traditional high voltage power supply are given.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN86;TN386

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