GaN (gallium nitride) buck-rectifier has been proposed to realize high power density ISOP (input series and output parallel)-IPOS (input parallel and output series) converter-based dc distribution system. The ul...GaN (gallium nitride) buck-rectifier has been proposed to realize high power density ISOP (input series and output parallel)-IPOS (input parallel and output series) converter-based dc distribution system. The ultra-low loss bi-directional switch can be developed by the GaN power device because of the low on-resistance, the high-speed switching behavior and its own device structure. The buck-rectifier using the GaN bi-directional switches has the potential to achieve higher power density than the commonly utilized boost-rectifier. Availability of the GaN-HEMT (high electron mobility transistor) for the buck rectifier has been verified taking the theoretical limit of the on-resistance and the switching loss energy into account. Design consideration for a high power density buck-rectifier has been also conducted and the application effect of the GaN bidirectional switches has been evaluated quantitatively. The ISOP-IPOS converter-based dc (direct current) distribution system takes full advantage of the buck-rectifier and the rectifier using GaN devices contributes to realizing higher power density dc distribution system.展开更多
In order to improve the ability of harmonic suppression,and reduce the loss of switching devices,this paper proposes an active harmonic suppression method at dc side of multi-pulse rectifier(MPR) . The circulating cur...In order to improve the ability of harmonic suppression,and reduce the loss of switching devices,this paper proposes an active harmonic suppression method at dc side of multi-pulse rectifier(MPR) . The circulating current through secondary winding of active inter-phase reactor(AIPR) is derived from the current relation between the ac and dc sides of MPR when the threephase input currents are sinusoidal simultaneously,and an applicable circulating current is presented. According to the relation between voltage across secondary winding of AIPR and the applicable current,it is confirmed that harmonic energy of input line current can be consumed by the resistor in series with the secondary winding. A half-bridge PWM rectifier is designed to abstract the harmonic power and to feed the load,which can realize the recycling of harmonic energy. Experimental results show that the power factor of the proposed system is approximately equal to one when the PWM rectifier operates normally,and that the proposed system has the ability of anti-variation of load and input voltage.展开更多
文摘GaN (gallium nitride) buck-rectifier has been proposed to realize high power density ISOP (input series and output parallel)-IPOS (input parallel and output series) converter-based dc distribution system. The ultra-low loss bi-directional switch can be developed by the GaN power device because of the low on-resistance, the high-speed switching behavior and its own device structure. The buck-rectifier using the GaN bi-directional switches has the potential to achieve higher power density than the commonly utilized boost-rectifier. Availability of the GaN-HEMT (high electron mobility transistor) for the buck rectifier has been verified taking the theoretical limit of the on-resistance and the switching loss energy into account. Design consideration for a high power density buck-rectifier has been also conducted and the application effect of the GaN bidirectional switches has been evaluated quantitatively. The ISOP-IPOS converter-based dc (direct current) distribution system takes full advantage of the buck-rectifier and the rectifier using GaN devices contributes to realizing higher power density dc distribution system.
基金supported by the National Natural Science Foundation of China (Grant Nos.50977018,51107019)the Fundamental Research Funds for the Central Universities (Grant No.HIT.NSRIF.2010101)
文摘In order to improve the ability of harmonic suppression,and reduce the loss of switching devices,this paper proposes an active harmonic suppression method at dc side of multi-pulse rectifier(MPR) . The circulating current through secondary winding of active inter-phase reactor(AIPR) is derived from the current relation between the ac and dc sides of MPR when the threephase input currents are sinusoidal simultaneously,and an applicable circulating current is presented. According to the relation between voltage across secondary winding of AIPR and the applicable current,it is confirmed that harmonic energy of input line current can be consumed by the resistor in series with the secondary winding. A half-bridge PWM rectifier is designed to abstract the harmonic power and to feed the load,which can realize the recycling of harmonic energy. Experimental results show that the power factor of the proposed system is approximately equal to one when the PWM rectifier operates normally,and that the proposed system has the ability of anti-variation of load and input voltage.