Systems and methods of powering a refrigeration unit of a hybrid vehicle

A system for powering a load coupled with a vehicle having a first power source, the system comprising:

• a power system coupled to the first power source, the power system configured to receive power from the first power source, a second power source, and a third power source, wherein the power system includes a power converter having a PWM rectifier, the power converter configured to receive a DC power and an AC power and configured to convert the received DC power and the received AC power into a second DC power;
• and
• a load control unit coupled to the power system, the load control unit receiving an indication from the power system of the availability of power from the first power source, the second power source, and the third power source;
• wherein the load control unit links power from the power system to the load when power is available from the power system,
• wherein the PWM rectifier includes:
• a bridge rectifier that converts the received AC power to the second DC power, wherein the bridge rectifier includes a plurality of diodes,
• a voltage control circuit that boosts a voltage of the second DC power, wherein the voltage control circuit includes a plurality of electronic switches, one of the plurality of electronic switches coupled across each of the plurality of diodes, and
• a pre-charging circuit that maintains power to the power converter when switching between the first power source, the second power source, and the third power source, and
• wherein the power converter includes a frequency inverter configured to receive the second DC power from the PWM rectifier and convert the second DC power to a third AC power, the third AC power supplied to the load.

A method of powering a load, the method comprising:

• receiving at a first input a first power from first power source;
• receiving at a second input a second power from a second power source;
• receiving at a third input a third power from a third power source;
• connecting the first input, the second input and the third input to a power converter, the connecting act coupling one of the first power source, the second power source, and the third power source to the power converter thereby resulting in a coupled power;
• converting the first power, the second power and the third power into a DC power by directing the first power, the second power and the third power through a PWM rectifier of the power converter;
• a voltage control circuit of the power converter boosting a voltage of the DC power;
• directing the DC power through a pre-charging circuit, the pre-charging circuit maintaining power to the power converter when switching between the first input, the second input, and the third input;
• directing the DC power outputted from the PWM rectifier to a frequency inverter, the frequency inverter converting the DC power into an output AC power;
• providing the output AC power to the load;
• and
• the pre-charging circuit buffering a current surge when switching between receiving the first power from the first power source and receiving the second power from the second power source, wherein buffering the current surge includes directing one of the first power and the second power through the pre-charging circuit at an output of the PWM rectifier, the pre-charging circuit including a pair of diodes coupled in series across the output of the bridge rectifier, an electronic switch coupled across one of the pair of diodes, and a resistor and a capacitor coupled in series across the output of the bridge rectifier, the resistor and the capacitor also coupled to the series connection of the pair of diodes.