Redundant power supply for HVAC system including refrigerant leakage mitigation
An exemplary heating ventilation and cooling (HVAC) system includes a multi-phase power input, an AC-DC rectifier connected to a DC-AC inverter via a DC power bus, a multi-phase power output connecting the DC-AC inverter to a fan blower motor, and at least one redundancy power system. The redundancy power system is configured to bypass at least one of the AC-DC rectifier and the DC-AC inverter.
1. A heating ventilation and cooling (HVAC) system comprising:
an air-conditioning unit containing a fan blower motor;
a power source including:
a multi-phase power input
an AC-DC rectifier connected to a DC-AC inverter via a DC bus,
a multi-phase power output connecting the DC-AC inverter to the fan blower motor, and
at least one redundancy power system configured to bypass at least one of the AC-DC rectifier and the DC-AC inverter; and
a controller configured to control operations of the HVAC system, the controller further configured to:
maintain the fan blower motor in a continuous operating state in response to a signal indicative of a refrigerant leak, and
activate the at least one redundancy power system in response to the presence of both a detected failure in the power source and the signal indicative of the refrigerant leak.
2. The HVAC system of claim 1 , wherein the at least one redundancy power system comprises a plurality of bypass switches connecting the multi-phase power input to the multi-phase power output.
3. The HVAC system of claim 2 , wherein the plurality of bypass switches include transistors, and wherein each of the transistors includes a control input.
4. The HVAC system of claim 3 , wherein each of said control inputs is electrically connected to the controller, the controller configured to control an open/closed state of each of the transistors.
5. The HVAC system of claim 4 , wherein the controller is configured to instruct each of the transistors to close in response to the detected failure in the power source.
6. The HVAC system of claim 1 , wherein the at least one redundancy power system comprises an energy storage system connected to the DC bus.
7. The HVAC system of claim 6 , wherein the energy storage system comprises at least one of a battery and a super capacitor.
8. The HVAC system of claim 6 , wherein the energy storage system is sized to power the fan blower for a maximum leak time, the maximum leak time determined by the total amount of refrigerant in the air conditioning unit.
9. The HVAC system of claim 1 , wherein the redundancy power system comprises one of a backup AC-DC rectifier and a backup DC-AC inverter arranged in parallel with a corresponding one of the AC-DC rectifier and the DC-AC inverter.
10. The HVAC system of claim 9 , wherein the redundancy power system comprises both the backup AC-DC rectifier and the backup DC-AC inverter arranged in parallel with the corresponding one of the AC-DC rectifier and the DC-AC inverter.
11. The HVAC system of claim 10 , wherein both the backup AC-DC rectifier and the backup DC-AC inverter are connected to the DC bus.
12. The HVAC system of claim 1 , wherein the at least one redundancy power system comprises a second AC-DC rectifier connected to a second DC-AC inverter via a second DC bus, wherein the at least one redundancy power system is parallel to the AC-DC rectifier and the DC-AC inverter.
13. The HVAC system of claim 1 , wherein the at least one redundancy power system includes a redundant input winding in the fan blower motor.
14. The HVAC system of claim 1 , wherein the controller is configured to maintain the fan blower motor in the continuous operating state for a duration of the refrigerant leak.
15. The HVAC system of claim 1 , wherein the at least one redundancy power system comprises a first redundancy power system and a second redundancy power system.
16. The HVAC system of claim 15 , wherein:
the first redundancy power system comprises a plurality of bypass switches connecting the multi-phase power input to the multi-phase power output; and
the second redundancy power system comprises an energy storage system connected to the DC bus.
17. The HVAC system of claim 1 , wherein the at least one redundancy power system comprises:
a plurality of bypass switches connecting the multi-phase power input to the multi-phase power output;
an energy storage system connected to the DC bus; and
a backup AC-DC rectifier and a backup DC-AC inverter arranged in parallel with the corresponding one of the AC-DC rectifier and the DC-AC inverter.