摘要 |
A local power generation system generates a substantially DC inverter input voltage, which is modulated to generate a resulting output AC power signal to a load. The inverter input voltage may be obtained from an engine generator, providing an AC power signal that is rectified, or from a fuel cell generator providing a DC voltage converted to the desired voltage value at the inverter input. An energy storage device helps maintain the DC voltage when load power increases, until the engine (or fuel cell reaction) accelerates enough to accommodate the increased demand. In an uninterruptible power supply (UPS) application, the load draws power from a utility-provided AC power source until a fault occurs. When the fault occurs, the load switches its draw to the inverter output. The energy storage device helps maintain the DC voltage at the inverter input until the generator (engine or fuel cell) starts and accelerates to a level sufficient provide the DC voltage. The system may also include switching devices for providing uninterruptible power to a critical load, while permitting a noncritical load to be subjected to a fault-condition for a short period of time, before switching to receive power from the inverter output. <IMAGE> |