Patent ID: 7375985
Filing Date: 2008-05-20
Classification: H02J,H02M,Y02E

Abstract:
1. A high efficiency single-stage multi-input bi-directional converter, comprising: a first DC input circuit, including first DC input voltage source; a second DC input circuit, including second DC input voltage source, i.e. rechargeable battery; a first winding circuit, including first winding of a coupled inductor and a first power semiconductor switch; the first winding of the coupled inductor is connected in series to the first power semiconductor switch; through on/off of the first power semiconductor switch controls energy storing and releasing of the first winding of the coupled inductor; a second winding circuit, including second winding of the coupled inductor and a second power semiconductor switch; the second winding of the coupled inductor is connected in series to the second power semiconductor switch; a third winding circuit, including third winding of the coupled inductor, a balance capacitor, a first high voltage diode, a second high voltage diode, a first high voltage capacitor and a second high voltage capacitor; one end of the third winding of the coupled inductor connects to positive end of the first high voltage capacitor, negative end of the first high voltage capacitor connects to positive end of the second high voltage capacitor, negative end of the second high voltage capacitor connects to input end of the second high voltage diode, the output end of the second high voltage diode connects to back to input end of the first high voltage diode; at the same time, the other end of the third winding of the coupled inductor connects to one end of the balance capacitor, and the other end of the balance capacitor connects to negative end of the first high voltage capacitor; a clamping circuit: including a clamping capacitor, a first clamping diode and a second clamping diode; output end of the first clamping diode and output end of the second clamping diode both connect to positive end of the clamping capacitor; a DC output circuit, including load, i.e., DC high voltage bus bar; a charging/discharging control and drive circuit, including feedback voltage of the first DC input voltage source, voltage of the second DC input voltage source and the DC output voltage; the charging/discharging control and drive circuit generates driving signal with adjustable duty cycle, to turn on and off the first and second power semiconductor switches; depending on the conditions of the first and second power semiconductor switches, three states exist; designating the first DC input voltage source is first preferred supplier; the first is discharging state, in which first and second power semiconductor switches are turned on/off at the same time; the second is charging state, in which first and second power semiconductor switches are turned on/off at the same time; the third is standalone state, in which only first power semiconductor switch is turned on/off.