Recharging system of hybrid vehicle using neutral points of two motors

A recharging system of a hybrid vehicle, comprising:

• a battery in which DC voltage is stored or for outputting the DC voltage;
• first and second motors configured to function as an electric motor or a generator;
• first and second inverters for operating the first and second motors respectively;
• a voltage converter (or raisins or lowering the DC voltage of the battery such that the raised or lowered DC voltage is supplied to the first and second inverters, in order to raise or lower the DC voltage supplied from the first and second inverters such that the raised or lowered DC voltage is supplied to the battery, and provided with a DC link;
• first and second diodes each provided with an anode terminal connected to a negative terminal of the first and second inverters, and a cathode terminal connected to a source of commercial electricity and connected in parallel to first and second neutral points of the first and second motors;
• a recharging controller for carrying out a recharging mode by detecting at least one of a phase of the commercial electricity supplied to the first and second neutral points of the first and second motors, a voltage of a DC link capacitor connecting the voltage converter and the first and second inverters, a battery voltage, a voltage of a smoothing capacitor connected at both terminals of the battery, a battery current, and a current flowing from the voltage converter to the battery, and controlling the voltage converter through a PWM duty according to the recharging mode of the batters such that the voltage of the DC link capacitor is raised or lowered, and is supplied to the battery;
• a main relay selectively connecting the battery with the voltage converter:
• a recharging port selectively connecting the commercial electricity disposed at an exterior of the vehicle to the first and second diodes;
• a connection detector for detecting a connection of the commercial electricity;
• and
• an input terminal switch mounted between the recharging port and the first and second motors and selectively connecting the commercial electricity to the first and second neutral points of the first and second motors by control of the recharging controller
• wherein the input terminal switch comprises:
• a first relay connected to the first diode and the first neutral point of the first motor;
• a second relay connected to the second diode and the second neutral point of the second motor;
• and
• a third relay connected in parallel with the first relay and connected in series with a resistance.