6-5. Considerations of Power Conversion Techniques in Future Space Applications PRAVEEN JAIN, J. BOTTRILL & M. TANJU Summary This paper presents some advanced concepts of DC/AC, DC/DC and AC/DC power conversion for high power space applications. Main design driving factors for these types of power conversion are presented. For high power applications, the resonant mode converters offer high efficiency, low mass and volume, reduced EMI, and high reliability. For DC/AC power conversion three types of resonant inverter configurations—parallel, series-parallel and hybrid, are investigated. Two basic control techniques, phase shift and pulse width modulation, are described and qualitatively compared. With the employment of MOS Controlled Thyristors (MCT) in these inverters, the pulse width modulation control technique is preferred. Both quantitative and qualitative analyses are presented. The series-parallel inverter has potential application where the ratio of peak power/average power demand is not large (not greater than 4:1). For the pulse power applications with large ratios of peak power/average power demand, the hybrid resonant inverter is best suited. The parallel resonant inverter is reserved for those applications which have severe short circuit requirements. For DC/DC power conversion, the pulse width modulated series, parallel and series-parallel resonant topologies are presented. Again, both quantitative and qualitative analyses are performed. These analyses show that the series resonant converter is suitable for all applications except low voltage, high current outputs. For low voltage and high current outputs, the series-parallel converter is preferred. For AC/DC power conversion, two new converter configurations (Type-1 and Type- 2) are introduced. These converters convert high frequency AC voltage to controlled DC voltage by using a single conversion stage and draw close to sinusoidal input current with a near unity power factor. This results in the highest efficiency and lowest mass. The Type-1 converter is suitable for the lower range of high power applications (up to approximately 1 kW). However, the Type-2 converter is best suited for higher power ratings. 1 Introduction Many future spacecraft systems will require high power to meet mission objectives. Designing and building high power space systems are challenging and expensive. Several studies on advanced space power systems, such as Space Station, show that Praveen Jain, J. Bottrill and M. Tanju, Canadian Astronautics Limited, Space Systems Group, 1050 Morrison Drive, Ottawa, Ontario K2H 8K7, Canada. Paper number IAF-ICOSP89-6-5.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==