Directed Energy weapon (DEW) systems are being developed for both ground and airborne applications. Typically, they consist of microwave or laser powered guns. Both the microwave application and the diode based laser applications require significant amount of power. This power ranges from several hundred kilowatts (kW) for microwave applications to Megawatts (MW) for laser applications. The laser application requires that the full power be available for short duration, typically 5 seconds, which could be repeated several times with short pauses in between. The control of a generator, which delivers Megawatt of the intermittent power greatly differs from the of normal steady state generator control. It poses significant challenges.
Application of power (and for this matter its removal) is a transient phenomenon that takes time and its effects ripple through the whole system. In the case at hand, the large applied power, which is required for a short duration, can have a more significant effect on the system. Furthermore, it is imperative that the full power will be available for the required duration with no degradation in quality on both ends (application and removal). There are four entities that interact affecting the performance of the system:
Controls: The generator regulator control loop
Power Generation: The generator electromagnetic and mechanical properties
Propulsion: The engine / FADEC transient performance characteristics
Load: Load transients and feeder impedances
Innovative Power Solutions and PC Krause and Associates under AF SBIR program conducted the investigation of different systems approaches to design a MW Digital Generator Control Unit (MDGCU) and selected the winning topology. The final MDGCU will control a class of 1MW continuous or intermittent generators (Figure 1 shows IPS designed 1MW intermittent generator).