应用于煤矿、石化等易燃易爆环境中的电子设备必须通过本安认证，目前判定其本安性能的方法主要包括爆炸性试验和非爆炸性方法。爆炸性方法存在评价过程繁琐、时间长、整改困难及评价结果可信性等问题；现有本安判据存在分析计算过程复杂、不便推广应用等问题。Buck-Boost变换器作为非隔离变换器的基本拓扑之一，可实现升、降压输出，且具有反极性功能，在危险环境的电气电子设备中得到广泛应用。因此，研究一种高效、便捷、可靠的Buck-Boost变换器非爆炸本质安全评价方法具有重要理论意义和实用价值。 针对Buck-Boost变换器实现本质安全面临的问题，通过设计合适的保护电路可组成本安型Buck-Boost变换器，其本安性能评价类型可分为输出本安和内部本安。分别分析了CCM与DCM、CISM与IISM的临界电感及不同模式下的峰值电感电流和输出纹波电压，推导得出了变换器在整个动态范围内的最大电感电流和最大输出纹波电压。 通过爆炸性试验对简单电容电路及Buck-Boost变换器的短路放电特性进行了对比分析，建立了模拟安全火花试验装置对其进行爆炸性试验的等效电路模型，且得出了模型参数的确定方法。深入研究负载电阻、输入电压等参数对输出短路放电能量的影响，对于给定参数的Buck-Boost变换器，存在一工作于CCM与DCM的临界负载电阻RLC，分别得到其工作于两种模式下的最大输出短路放电能量。通过分析全动态范围内的最大输出短路火花能量，得到了Buck-Boost变换器最危险的输出短路放电工况，据此提出一种爆炸性试验评价输出本安性能的可信方法。根据能量等效原理，得出了模拟Buck-Boost变换器的输出短路放电引燃能力的等效电容及等效简单电容电路，依据临界点燃电压曲线得出了Buck-Boost变换器的输出本安判据。 应用安全火花试验装置对简单电感电路及Buck-Boost变换器内部电感的分断电弧放电特性进行了试验研究，依据描述分断电弧放电的线性衰减模型，对分断电弧放电持续时间进行了分析，建立了模拟爆炸性试验的时变电阻模型，得出了模型参数的求取方法。对给定Buck-Boost变换器工作于不同模式下的分断电弧放电能量进行了分析，得出了对应于最大分断电弧放电能量的最危险工况及相应元件与性能指标参数，据此提出一种爆炸性试验评价内部本安性能的可信方法。根据能量等效原理，得出了模拟Buck-Boost变换器的分断电弧放电引燃能力的等效电感及等效简单电感电路，依据感性电路的临界点燃电流曲线得出了Buck-Boost变换器的内部本安判据。 应用MATLAB的Cftool工具箱，以三次样条插值法对临界点燃电压和电流曲线进行拟合，通过程序设计实现了临界点燃曲线的数值化查询。以Buck-Boost变换器的非爆炸性本安判据、模拟其电感分断与输出短路放电的等效电路模型及临界点燃曲线的数值化查询为基础，建立了基于MATLAB的本安性能评价系统。采用Saber和MATLAB的Simulink模块搭建待评价的Buck-Boost变换器电路，通过回调函数提取变换器的关键运行参数，求取分断及输出短路最大放电能量，利用能量等效原理得到等效电感及等效电容，并与数值化查询所得临界电感和临界电容进行比较，从而评估Buck-Boost变换器的内部及输出本安性能，在GUI界面中就能直观显示所提取参数及本安评价结果。采用评价系统及爆炸性试验对Buck-Boost变换器的本安性能进行判定，结果验证了所建立评价系统的可行性。

Electronic devices applied in high risk industrial environments should comply with intrinsic safety certification compulsorily, such as inflammable and explosive coal mines and petrochemical industry. Two kinds of methods, explosive and non-explosive, are always employed in intrinsic safety performance evaluation. Explosive methodstake long time in experiments and evaluations, but get low credibility in results, which are not reliable for afterwards improvements and also not qualified for further widespread promotions. As one of the most important non-isolated topologies, buck-boost circuit can realize DC/DC conversion flexibly with reversed input-output polarity, which is widely used in high risk ndustries. Develop effective and reliable no-explosive intrinsic safety performance evaluation technology for buck-boost converter application will significantly benefit social and scientific interest theoretically and practically. Auxiliary circuit for protection is then developed, together with which the buck-boost converter is improved to intrinsic safe type. Two aspects of intrinsic safety evaluation processes are carried out, including internal and output of a buck-boost converter. Critical inductance under CCM, DCM, CISM and IISM conditions are calculated, respectively. Meanwhile, peak current of the inductor and maximum output voltage ripple in each mode are evaluated with whole range variations of load, input voltage and output voltage. Through explosive test to basic capacitor circuit and short circuit experiment of buck-boost converter, explosive equivalent circuit model of buck-boost converter is established based on spark experimental circuit. Furthermore, parameter determination approach of this model is proposed. Then further information of sparking energy with different loads and input voltage levels are collected.For a buck-boost converter with certain parameters, there is a critical resistance RLC, which is separating DCM and CCM. Then the maximum short-circuit spark energy in two modes are evaluated through testing and causation. By analyzing the maximum discharge energy in all working situations, a credible intrinsic safety evaluation criterition is proposed based on explosive experiments. According to energy balance principle, under short circuit output conditions the buck-boost converter can be equivalent to a capacitor circuit with equal energy. Then according to critical arcing voltagecurve, the output intrinsic safety criterion is derived. With similar philosophy, through safe explosive test to basic inductor circuit and open circuit experiment of inductor in buck-boost converter, explosive equivalent time varying resistor model is established based on breaking arc sparking linear attenuation characters. Furthermore, parameter determination approach of this model is proposed. Then further information of breaking arc sparking energy with different loads and input voltage levels are collected.For a buck-boost converter with certain parameters, the extreme working conditions and paramour valuesare then derived and a credible intrinsic safety evaluation criteria is proposed based on explosive experiments. According to energy balance principle, under inductor open circuit condition, the buck-boost converter can be equivalent to an inductor circuit with equal energy. Then according to critical arcing voltage curve, the internal intrinsic safety criterion is derived. Cftool toolbox of MATLAB is activated to refine the proposed criteria through cubic spline interpolation method. The critical sparking voltage and current curves can be derived and refined, making the criteria more flexible in a numerical way.Furthermore, Saber and Simulink toolbox is applied to build a Buck-Boost converter, then the key operation status are collected by recall function to estimate the maximum breaking and short circuit sparking energy. From the proposed approach, equivalent inductance and capacitance can be calculated, which are compared with the results from numerical inquire, then the internal and output intrinsic safety of a boost converter is evaluated, which can be clearly presented in GUI. All this work has proved effectiveness of the proposed intrinsic safety criteria for buck-boost converter.