Advances in solid-state RF cooking technology mean that we can now control the way we cook with precision, producing high-quality food quickly. We expect its use to grow in both commercial and domestic settings. However, its integration into ovens presents a number of challenges, not least of which is thermal design, or how we deliver RF power for cooking while keeping the delivery system cool, in a cost efficient manner. An article published in AMPERE Newsletter discusses this topic and the tools Goji uses to address the challenge successfully.
The solid-state power transistors used in Goji’s RF cooking technology are comprised of a semiconductor die attached to a metal base, packaged and connected with bond wires to external conductors. The transistor delivers RF output to the oven cavity, and it is precise control of this element that enables different food loads to be cooked appropriately. As it can generate 250 watts of RF power, has a maximum operating temp of around 200 degrees Celsius, and produces up to 200 watts of dissipated heat, having an effective cooling system is crucial.
Having designed the first complete RF cooking system to be fully integrated into an oven for domestic use, the Goji engineering team is well-versed in these challenges.
Factors such as acoustic noise level, size and cost must be taken into consideration in the thermal management of RF cooking systems. Coupled with this, balancing cost and performance are critical in bringing any appliance for use in the home to the market. Having designed the first complete RF cooking system to be fully integrated into an oven for domestic use, the Goji engineering team is well-versed in these challenges.
Goji’s Vecton™ RF power module has a base plate constructed from die-cast aluminum, which helps minimize its cost. We knew that embedding a copper insert in the base plate would make it a more efficient heat sink, thanks to the higher thermal conductivity of copper, compared to aluminum. Copper is significantly more expensive than aluminum, but by running a heat sink simulation, our team were able to identify the optimal balance between cooling performance and raw materials cost.
In developing tools and processes designed to optimize thermal management, while also balancing performance and cost, Goji engineers are bringing solid-state RF cooking technology closer to the mass consumer market. Our experience also enables us to provide services to appliance companies seeking to improve the thermal management of their own RF systems.
The full article on Thermal Management of Solid-State RF Cooking Appliances is available on pages 14 to 18 in Issue 91 of AMPERE Newsletter.
RF cooking utilizes a high power solid-state amplifier which, as part of a complete RF module, transmits radio wave energy into an object to heat it. Unlike the magnetron in a microwave oven, the digital RF module can accurately control the frequency, amplitude and phase of the radio-waves. When combined with Goji’s proprietary closed-feedback sensing algorithm, the RF module enables more uniform and consistent cooking results, while shortening and simplifying the cooking process.
Goji develops and markets RF cooking technologies for household, commercial and industrial applications in the food industry. The novel Goji™ technology facilitates controlled and responsive heating, delivering unprecedented cooking performance. The company holds a broad IP portfolio, with over 200 issued and pending patents on its technology. Goji provides a full range of licensing, design and manufacturing services to commercial and white goods appliance manufacturers. For more information, visit www.gojifoodsolutions.com.