Patent ID: 8610483

Claim:
A voltage-limiting circuit, comprising: a) a series branch circuit comprising a plurality of power switching devices, the plurality of power switching devices comprising a first power switching device; b) a plurality of energy temporary-storage circuits, the plurality of energy temporary-storage circuits comprising a first energy temporary-storage circuit, the first energy temporary-storage circuit comprising a first energy return end; and c) a centralized voltage-limiting circuit for limiting voltage for the series branch circuit; wherein: each of the plurality of power switching devices comprises a control terminal, a high-end, and a low-end; in the series branch circuit, the series connection of the plurality of power switching devices is that a high-end of a power switching device is connected with a low-end of another power switching device in series; each of the plurality of power switching devices is connected in parallel with one energy temporary-storage circuit; each of the plurality energy temporary-storage circuits comprises a clamping diode, an energy storage capacitor, a static voltage-sharing resistor, and an energy return end; in each of the plurality of energy temporary-storage circuits, the energy storage capacitor is connected in parallel with the static voltage-sharing resistor to form the energy return end, and then connected in series with the clamping diode; the centralized voltage-limiting circuit comprises a voltage-limiting functional circuit and a plurality of energy concentration diodes for concentrating the energy temporarily stored by the corresponding energy temporary-storage circuits, the plurality of energy concentration diodes comprising a first energy concentration diode and a second energy concentration diode; the voltage-limiting functional circuit returns inflow energy to a power supply or provides inflow energy for a load converter; anodes and cathodes of the plurality of energy concentration diodes except the first energy concentration diode are in series connected in sequence; anodes of the plurality of energy concentration diodes except the first energy concentration diode are connected with the corresponding energy return ends, respectively; a cathode of the second energy concentration diode is connected with the first energy return end; a high voltage end of the voltage-limiting functional circuit is connected with a cathode of the first energy concentration diode, and a low voltage end of the voltage-limiting functional circuit is connected with a high-end of the first power switching device; and an anode of the first energy concentration diode is connected with an energy return end of the first energy temporary-storage circuit.