Power systems and methods using an uniterruptible power supply to transition to generator-powered operation
A loss of a power source for a bus is detected. Responsive to detecting the loss of the power source, a voltage is generated on the bus using an uninterruptible power supply (UPS). A generator is transitioned to a desired output state concurrent with generating the voltage on the bus using the UPS. The generator is coupled to the bus responsive to the generator attaining the desired output state. The UPS may be used to provide power to a load connected to the bus while the generator is in transition. For example, detecting the loss of the power source may be preceded by operating a converter of the UPS coupled to the bus as a rectifier and generating the voltage on the bus using the UPS may include operating the converter of the UPS as an inverter.
1. A method of operating a power system, the method comprising:
detecting a loss of a power source that supplies power to an uninterruptible power supply (UPS) and load via a first bus;
responsive to detecting the loss of the power source, disconnecting the first bus from a second bus that connects the first bus to the lost power source;
generating a voltage on the first bus using the UPS to thereby provide power from the UPS to the load;
transitioning a generator to a desired output state concurrent with generating the voltage on the first bus using the UPS; and
coupling the generator to the first bus via the second bus responsive to the generator attaining the desired output state to enable power transfer from the generator to the UPS and the load.
2. The method of claim 1 , wherein the load comprises cooling equipment that cools electronic equipment served by the UPS.
3. The method of claim 1 , wherein coupling the generator to the first bus via the second bus responsive to the generator attaining the desired output state comprises:
coupling the generator to the second bus responsive to transition of the generator to the desired output state; and then
coupling the first bus to the second bus.
4. The method of claim 3 , further comprising coupling a load to the second bus following coupling of the generator to the second bus and prior to coupling the first bus to the second bus.
5. The method of claim 1 , wherein transitioning the generator to the desired output state concurrent with generating the voltage on the first bus using the UPS comprises synchronizing the generator with the UPS.
6. The method of claim 1 :
wherein detecting the loss of the power source is preceded by operating a converter of the UPS coupled to the first bus as a rectifier; and
wherein generating the voltage on the first bus using the UPS comprises operating the converter of the UPS as an inverter.
7. The method of claim 1 , wherein generating the voltage on the first bus using the UPS comprises coupling an inverter output of the UPS to the bus via a bypass.
8. The method of claim 1 , further comprising providing power to a critical load connected to the UPS concurrent with generating the voltage on the first bus using the UPS.
9. A power distribution system comprising:
a first bus;
a UPS configured to be coupled to the first bus;
a second bus configured to be coupled to the first bus to provide power from a power source to the UPS and a load via the first bus;
a generator configured to be coupled to the second bus; and
a control circuit operatively coupled to the UPS and the generator and configured to detect a loss of the power source, to disconnect the first bus from the second bus responsive to detection of the loss of the power source, to cause the UPS to generate a voltage on the first bus responsive to detection of the loss of the power source to thereby provide power from the UPS to the load, to transition the generator to a desired output state concurrent with generating the voltage on the first bus using the UPS and to couple the generator to the first bus via the second bus responsive to the generator attaining the desired output state to enable power transfer from the generator to the UPS and the load.
10. The system of claim 9 , wherein the load comprises cooling equipment that cools electronic equipment powered by the UPS.
11. The system of claim 9 , wherein the control circuit is configured to couple the generator to the second bus responsive to the generator attaining the desired output state and to subsequently couple the first bus to the second bus.
12. The system of claim 9 , wherein the control circuit is configured to couple a load to the second bus following coupling of the generator to the second bus and prior to coupling the first bus to the second bus.
13. The system of claim 9 , wherein the control circuit is configured to synchronize the generator responsive to the voltage generated on the first bus by the UPS.
14. The system of claim 9 , wherein the control circuit is configured to operate a converter of the UPS as a rectifier prior to detecting the loss of the power source and to operate the converter of the UPS as an inverter to generate the voltage on the first bus using the UPS.