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Systems and methods for operating a variable speed drive to receive an input AC power at a fixed AC input voltage and frequency and provide an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter stage to convert the input AC voltage to a booste

Systems and methods for operating a variable speed drive to receive an input AC power at a fixed AC input voltage and frequency and provide an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter stage to convert the input AC voltage to a boosted DC voltage, a DC link connected to the converter stage to filter and store the boosted DC voltage from the converter stage; and an inverter stage to convert the boosted DC voltage into AC power with variable voltage and the variable frequency. An integral bypass contactor is connected in parallel with the VSD between the AC power source and the AC output power. The integral bypass contactor is arranged to bypass the VSD when the VSD output frequency and voltage are approximately equal with the AC input voltage and frequency.

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What is claimed is: 1. A variable speed drive system (VSD) configured to receive an input AC voltage at a fixed AC input voltage and frequency, and provide an output AC power at a variable voltage and variable frequency, the variable speed drive comprising:a converter stage connected to an AC power

What is claimed is: 1. A variable speed drive system (VSD) configured to receive an input AC voltage at a fixed AC input voltage and frequency, and provide an output AC power at a variable voltage and variable frequency, the variable speed drive comprising:a converter stage connected to an AC power source providing the input AC voltage, the converter stage being configured to convert the input AC voltage to a boosted DC voltage;a DC link connected to the converter stage, the DC link being configured to filter and store the boosted DC voltage from the converter stage;an inverter stage connected to the DC link, the inverter stage being configured to convert the boosted DC voltage from the DC link into the output AC power having the variable voltage and the variable frequency;an integral bypass contactor connected in parallel with the VSD between the AC power source and the AC output power, the integral bypass contactor configured to bypass the VSD when the VSD output frequency and voltage are approximately equal with the AC input voltage and frequency; andan output current limiting control and a sensorless torque control;the output current limiting control configured to limit the amount of output current available at the AC output power to a predetermined current value; andthe sensorless motor torque control configured to control the motor torque based on a motor current and motor voltage.