Optically Gated, Silicon Carbide Semiconductors for Aircraft Electrical Actuator Motor Drives

We propose an optically controlled power switch based on 4H-SiC TI-VJFETs for applications in EHA and EMA actuator motor drives for air platforms. It comprises a UV LED light source driver, an integrated gate buffer driver and a high power 4H-SiC TI-VJFETs as power switch. The UV LED light source driver includes a driver circuit and UV LED light source with a wavelength of 375nm or less. The integrated gate buffer driver includes a unipolar Darlington structure formed by two or more stages of 4H-SiC TI-VJFETs. The integrated gate buffer driver and the power switch are designed to be able to operate at temperatures up to 200C and are suitable for 600-1200V, 10-100A applications. In phase I, we propose to experimentally demonstrate a prototype of the proposed optically controlled power switch using the integrated gate buffer driver. In phase II, we propose to perform the major R&D work, fabricate and characterize multiple batches of the proposed optically controlled power switch, improve the design and push up the voltage and current of the optically-controlled switch to 1.2kV-100A, build SiC-based UV LED driver so that the entire switch can be operated at temperatures up 200C. Phase III will focus on commercialization development.   BENEFIT: Anticipated benefits include a new power switch with inherent immunity to dynamic electromagnetic events, having high-reliability and harsh-environment operability, capable of high temperature operation, having improved component efficiency with reduced on-state and switching losses, and having higher frequency switching capability.  A successfully developed optically controlled EHA or EMA flight surface control subsystem based on the optically-controlled switch could dramatically increase the survivability of air and other DoD platforms.  An additional benefit is the possibility of reducing the volume and weight associated with conventional filters used to protect low-voltage control devices from the inherent radiated EMI associated with switching large voltages and currents.  Commercial applications would include HV DC transmission, over-voltage protection systems and circuit breakers.