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Analysis and design of PDM HF converter for mining local fanner

Driven by the compulsory requirement of dilution the deleterious gas immediately in coal well underground laneway for safety production, a novel pulse density modulation (PDM) HF converter for the mining local fanner is introduced in the paper. In this PDM converter, the high frequency technique is employed to minimize the converter cubage owing to the limitation of the small work space in the underground laneway. PDM switch mode is analyzed, and soft switched control strategy is implemented. Computer simulation is carried out to estimate the characteristics of the converter. The performance results show that PDM HF converter is effectively reduce switching loss in high frequency application and has the merit of the lightweight for the mining local fanner drive system.