Extremely low loss circuit for megawatt average power switch testing

Testing of megawatt average power switches has become prohibitively expensive in conventional RLC circuits. The major costs are the power supply, the resistive load, the heat removal system, and electricity. A several hundred thousand dollar investment in a megawatt average power, high voltage supply to be completely utilized in a year-long life test can itself drive the cost of testing to several thousands dollars per hour. At this rate a single day's testing can cost as much as the device under test. If the cost of cooling water, ancillary equipment, electricity, and overhead is included, the total cost to life-test a few thousand dollar component can approach nearly one million dollars. To reduce these costs, a new class of high power pulse component test circuits have been developed to test megawatt average power devices at full power ratings, but with only kilowatts of input power. These "artificial" test circuits reduce the size of the power supply, nearly eliminate the cooling requirement, and reduce the power consumption to a reasonable and affordable level. The figure of merit for these circuits is expressed as Power Switched/Power In. This ratio can approach 100 as the efficiency of the artificial test circuit is optimized. The system described in this report is one of the new near loss-free test circuits. This particular circuit is specifically designed for lower voltage (<20 kV) components and includes provisions for pulse shaping along with an affordable way to test megawatt average power devices.