基于数字控制的高频高压电源

发布时间：2018-01-23 03:31

本文关键词： 高频高压电源数字控制功率因数校正移相控制单周期控制　出处：《西安电子科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：当前高压电源在很多领域得到了广泛的应用,医疗、通信、国防等领域都离不开高压电源。本文所研究的高频高压电源主要应用于X射线衍射仪,为其提供10KV~60KV的工作电压。X射线衍射仪对电源的要求很高,电源电压的稳定性和控制精度直接影响X射线衍射仪的成像质量。高频开关电源的出现实现了高压电源的高精度、高效率,很适合用于X射线衍射仪,因此本文采用了高频开关电源的设计方案。本文设计的基于数字控制的高频高压电源不仅实现了电源的高频化,同时采用了基于数字的控制方案,简化了控制电路的复杂度,提高了输出电压的控制精度。电源采用了常用的两级结构,前级的PFC(功率因数校正)电路和后级的串并联谐振电路。PFC电路采用了单周期控制策略,实现了输入电流与输入电压同相位,提高了电源的功率因数。串并联谐振电路不仅具有串联谐振和并联谐振的优点,同时克服了这两种电路的缺点,并且容易实现软开关。由于采用了数字控制方式,控制芯片输出控制信号不能直接驱动MOS管,并且谐振电路的工作电压比较高,控制电路和开关管之间也要做相应的电气隔离。因此专门设计了驱动电路,实现对开关管的控制。此外各个控制芯片和驱动电路需要低压驱动,本文专门设计了辅助电源为其提供工作电压。考虑到辅助电源需要低压多路输出,最终采用了单端反激式拓扑结构。文中通过对各部分电路的分析,给出了电路的等效模型,推导出影响电路性能的关键元件参数选定公式。对功率因数校正电路和串并联谐振电路进行了建模仿真,验证了单周期控制原理的正确性,并根据仿真结果对电路的部分参数进行了优化。本文对高压电源各部分元件进行了分析和计算,并根据计算结果制作出了试验样机。经过测试,各部分性能基本达到设计要求,接下来要对参数做进一步的优化。
[Abstract]:At present, high voltage power supply is widely used in many fields, such as medical treatment, communication, national defense and other fields can not be separated from high voltage power supply. The high frequency high voltage power supply studied in this paper is mainly used in X ray diffractometer. The working voltage of 10kV / 60KV. X ray diffractometer has a high requirement for power supply. The stability and control precision of power supply directly affect the imaging quality of X-ray diffractometer. The appearance of high frequency switching power supply realizes the high precision and high efficiency of high voltage power supply, which is very suitable for X-ray diffractometer. Therefore, the design scheme of high frequency switching power supply is adopted in this paper. The high frequency and high voltage power supply based on digital control not only realizes the high frequency of power supply, but also adopts the digital control scheme. The complexity of the control circuit is simplified and the control precision of the output voltage is improved. The former PFC (Power Factor Correction) circuit and the series and parallel resonant circuit. PFC circuit adopt a single period control strategy to realize the same phase of input current and input voltage. The series and parallel resonant circuit not only has the advantages of series resonance and parallel resonance, but also overcomes the shortcomings of these two circuits. Because of the digital control mode, the output control signal of the control chip can not drive the MOS transistor directly, and the working voltage of the resonant circuit is relatively high. Therefore, the drive circuit is specially designed to realize the control of the switch tube. In addition, each control chip and drive circuit need low-voltage drive. In this paper, the auxiliary power supply is specially designed to provide the working voltage. Considering that the auxiliary power supply needs low-voltage multi-output, the single-end flyback topology is adopted. The circuit of each part is analyzed in this paper. The equivalent model of the circuit is given, and the selection formula of the key component parameters affecting the performance of the circuit is derived. The power factor correction circuit and the series-parallel resonant circuit are modeled and simulated. The correctness of the single-cycle control principle is verified, and some parameters of the circuit are optimized according to the simulation results. In this paper, the components of the high-voltage power supply are analyzed and calculated. According to the calculation results, the experimental prototype is made. After testing, the performance of each part basically meets the design requirements, and then the parameters should be further optimized.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN86

【相似文献】