The solid state RF microwave oven has no magnetron or heavy transformer that has been the mainstay of microwave oven design since the first one was launched by Raytheon in 1947. Among key breakthroughs was the invention of an oscillation scheme that produces 2450 MHz using Freescale devices aimed at cell phone applications.
Moving to a solid state design allows more controllability and intelligence in the oven design and lower noise operation, as well as longer life, lower voltage operation, full DC operation capability and smaller footprint.
The design has seen seven key technology breakthroughs, each with a patent application, including four fundamental 'invention' patents. These include RF high-power synthesis technology, RF output power adjustable technology, RF microwave oven heating efficiency promotion technology, heating frequency automatic control technology, the technology of RF microwave feeding, RF power source load rigid lifting technology and RF microwave oven matching technology.
The first oven has three power levels including 150W, 300W and 600W output. Midea plans to continue research and development in order to launch higher output power microwave ovens using Freescale LDMOS solid state RF power semiconductor technology.
Established in 1968, Midea has grown from what was once a local workshop into a leading consumer appliances and air conditioning systems manufacturer with a global turnover of $22bn last year.