Design Method of Output Intrinsic Safety Boost Converter Based on Minimum Frequency and Considering Temperature Effects

Aiming at the complexity caused by the multiple iterations and the unreliability resulted by ignoring the temperature effect in the traditional design method of the output intrinsic safety boost converter (OISBC), the convenient and reliable design method is proposed. Through analyzing the relationship among output voltage ripple (OVR), intrinsic safety performance (ISP), operating frequency, and component parameters, it is concluded that the maximum capacitance ${C} _{\mathbf {max}}$ allowed by ISP requirement is independent of operating frequency, and the minimum capacitance ${C} _{\mathbf {min}}$ meeting OVR requirement increases with the decrease of operating frequency. When ${C} _{\mathbf {min}}$ equals ${C} _{\mathbf {max}}$ , the corresponding operating frequency is defined as the minimum frequency ${f} _{\mathbf {min}}$ , and its expression is derived. Assuming a capacitance change range, the capacitance adjustment factor is introduced. Considering the influence of the temperature change on OVR and ISP, the reliable capacitance adjustment factor $\alpha _{\mathbf {T}}$ and value range of the capacitance are derived. The actual operating frequency can be obtained according to ${f} _{\mathbf {min}}$ and $\alpha _{\mathbf {T}}$ . Finally, the specific design flow of the proposed design method based on ${f} _{\mathbf {min}}$ and considering temperature effects is presented. The feasibility of the proposed design method of the OISBC is verified by experimental results.