开关电源本安防爆性能试验与评价的理论及方法研究

At present, the explosive test is the only effective method to evaluate the intrinsically safe explosion-proof performance of a switching power supply. However, due to the potential problems in the test conditions, its evaluating results may be questioned. Moreover, because only a few institutions have the explosive test conditions, the researches on the intrinsically safe switching power supply have to be restricted. To solve these problems, its typical breaking and short-circuit spark discharge characteristic curves are obtained through the explosive test of the switching power supply by using the safety spark test apparatus in this project. The equivalent circuits and their corresponding system-level simulation models are searched, which can simulate the breaking and short-circuit spark discharge characteristics of the switching power supply. A simulating test system is built to simulate the breaking and short-circuit explosive test of the switching power supply on the safety spark test apparatus. The numerical analysis method is explored to evaluate the intrinsic safety performance of the switching power supply. Just entering the topology of the switching power supply and its relevant parameters, its limit parameters are analyzed and its safety performance is evaluated. Through the numerical simulation analysis of safety performance in the whole operating ranges, the most dangerous breaking and short-circuit spark discharge conditions are concluded. The theories and methods to improve the credibility of the explosive test method are studied. The simulation test system and numerical simulation analysis method can provide theoretical guidance for the design of the intrinsically safe switching power supply products and test & evaluation of the intrinsically safe explosion-proof performance, and make an important contribution to the safe production of coal mines and other dangerous fields.

爆炸性试验是目前评判开关电源本安防爆性能的唯一有效方法，但由于其试验工况存在潜在问题，致使其评判结果受到质疑；同时，只有少数机构具备进行爆炸性试验的条件，也制约了相关企业对本安防爆开关电源的研究。为此，本项目拟通过安全火花试验装置对开关电源进行爆炸性试验，得出其典型分断及短路火花放电特性曲线；寻求能模拟开关电源分断及短路火花放电特性的等效电路及其对应系统级仿真模型；构建能模拟开关电源进行开闭爆炸性试验的仿真试验系统；探索开关电源本安性能的数值仿真评价方法，只需输入开关电源拓扑结构及电路参数，即可对其极限参数进行分析并评判其本安性能；对开关电源整个动态范围内的本安性能进行仿真试验和数值仿真分析，得出其最危险的分断及短路放电工况，并研究提高爆炸性试验评价结果可信度的理论及方法，为本安防爆开关电源产品的设计及其本安防爆性能的试验与评价提供理论指导，对煤矿等危险行业的安全生产作出贡献。

应用于煤矿等危险环境的本安电源必须要通过本安认证，评估其本安性能的方法包括爆炸性试验和非爆炸性评价。爆炸性试验存在研发周期长、成本高等不足，且不能直接指导本安开关电源的研制，还不能确保评价结果的可信性，因此，研究提高评价结果可信度的理论及方法，建立本安性能评价系统具有重要理论意义和实用价值。. 应用安全火花试验装置对开关变换器的输出短路及分断电弧放电特进行研究，指出其输出短路放电机制是场致发射。通过建立电极微凸起物理模型及短路放电数学模型，得出了场致发射增强因子的解析式。指出最小建弧电压与初始电感电流无关，建立了电弧电阻模型，得出了模拟分断电弧放电的数学模型。. 依据开关变换器分断及短路放电电压、电流波形，建立了可模拟安全火花试验装置对开关变换器进行分断及短路爆炸性试验的等效电路模型，求取了电路模型参数，得到了电弧放电电阻的解析式，实验结果说明所建立的模型能较准确地反映开关变换器的分断电弧放电及输出短路火花放电特性。. 对开关变换器的输出短路放电能量进行了深入分析，考虑到电气及元器件参数的实际取值范围，得出了使得火花放电能量最大的最危险输出短路放电工况。对于开关变换器的分断电弧放电，依据能量守恒求得等效电感，并推导得出了使得等效电感最大的最危险分断放电工况。将最危险工况参数作为爆炸性试验条件，可提高评价结果的可信度。. 建立了基于MATLAB的本安性能评价系统，通过回调函数提取关键参数，求得等效电容或电感，并与查询数值化最小点燃曲线得到的临界电容或电感进行比较，判定输出或内部本安性能。通过所建立的本安评价系统，可缩短本安开关变换器的研制周期，节约研发成本。. 针对非最小相位本安开关变换器系统的负调问题，分析了负调电压随电气及元件参数的变化关系，提出了抑制负调的非线性限幅控制策略及元件参数设计方法。发明了电感能量旁路电路及自恢复截止型保护电路，有助于促进大功率本安电源及电气设备在煤矿等危险环境的推广应用。