Multi-pulse constant voltage transformer for a variable speed drive in chiller applications

A variable speed drive system, comprising:

• a multiple pulse transformer connected to a three-phase AC power source configured to provide input AC voltage;
• a converter configured to convert the input AC voltage to a DC voltage;
• a DC link connected to the converter, wherein the DC link is configured to filter and store the DC voltage from the converter;
• an inverter connected to the DC link, wherein the inverter is configured to convert the DC voltage from the DC link into output AC power having a variable voltage and a variable frequency;
• and
• a control panel configured to output a control signal to the variable speed drive system to adjust the output AC power based on feedback indicative of a condition of a vapor compression system;
• wherein the multiple pulse transformer comprises:
• three primary windings, each of the primary windings connected to a phase of the three-phase AC power source, each of the primary windings comprising a plurality of input terminals for connection to the three-phase AC power source, wherein a first input terminal of the plurality of input terminals is wound for a first utility voltage available at the three-phase AC power source, and a second input terminal of the plurality of input terminals is wound for a second utility voltage available at the three-phase AC power source, and wherein the first utility voltage is different than the second utility voltage;
• and
• a plurality of secondary phase windings, each secondary phase winding having multiple voltage output terminals.

A chiller system, comprising:

• a refrigerant circuit comprising a compressor, a condenser, and an evaporator connected in a closed refrigerant loop;
• a converter;
• a DC link connected to the converter;
• an inverter connected to the DC link;
• and
• a multiple pulse transformer comprising three primary windings connected to a three-phase AC power source and a plurality of secondary windings connected to a variable speed drive to power a motor of the compressor,
• wherein each of the primary windings comprises a plurality of input terminals for connection to the three-phase AC power source, wherein a first input terminal of the plurality of input terminals is wound for a first utility voltage available at the three-phase AC power source, and a second input terminal of the plurality of input terminals is wound for a second utility voltage available at the three-phase AC power source, wherein the first utility voltage is different than the second utility voltage, and wherein each secondary winding comprises multiple voltage output terminals.