Intrinsically safe switching converters are the best choice for low-voltage DC power supplies in explosive environments (such as coal mine). To obtain the optimal design method of the inner-intrinsically safe buck-boost converter (IISBBC), the equivalent circuits for various switching states and operating conditions of the buck-boost converter are studied, and the most dangerous inductor-disconnected discharge (IDD) condition of the buck-boost converter is obtained. Based on this condition, the IDD behavior of the IISBBC is studied. According to the minimum ignition curves (MICs) of the resistive circuit and the simple inductive circuit, the expressions describing the IDD ignition capability of the IISBBC in terms of the critical ignition power and the critical ignition energy are derived. The IDD has the strongest ignition capability based on power when the IISBBC is working at its maximum input voltage and minimum load resistance, and it has the strongest ignition capability based on energy when the IISBBC is working at its minimum input voltage and minimum load resistance. The converter is inner-intrinsically safe only when the maximum arc power is less than the critical ignition power and the inductive energy is less than its critical value. By incorporating the proposed criterion, the optimal design method for IISBBCs that meets the demands of electric and inner-intrinsic safety performance is obtained. Based on this method, the design range of the inductance and capacitance and the optimal inductance to give the IISBBC the best inner-intrinsic safety performance are obtained. The feasibility and reliability of the proposed optimal design method are demonstrated by an explosion test.

中文翻译：

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基于点火能力的本安型降压-升压变换器的优化设计方法

本质安全型开关转换器是爆炸性环境（例如煤矿）中低压直流电源的最佳选择。为了获得本安型降压-升压转换器（IISBBC）的最佳设计方法，研究了降压-升压转换器各种开关状态和工作条件的等效电路，以及最危险的电感器断开放电（IDD）获得降压-升压转换器的条件。基于此条件，研究了IISBBC的IDD行为。根据电阻电路和简单电感电路的最小点火曲线（MIC），推导了根据临界点火功率和临界点火能量描述IISBBC的IDD点火能力的表达式。当IISBBC在其最大输入电压和最小负载电阻下工作时，IDD基于功率的点火能力最强，而当IISBBC在其最小输入电压和最小负载电阻下工作时，IDD基于能量的点火能力最强。仅当最大电弧功率小于临界点火功率且感应能量小于其临界值时，转换器才具有内部本质安全性。通过结合提出的标准，获得了满足电气和内在安全性能要求的IISBBCs的最佳设计方法。基于此方法，获得了使IISBBC具有最佳内部本安性能的电感和电容的设计范围以及最佳电感。