Four-kilowatt homogeneous microwave heating system using a power-controlled phase-shifting mode for improved heating uniformity

• Published in: Electronics letters 2019-04, Vol.55 (8), p.465-467
• Main Authors: Jeong, C.-H, Ahn, S.-H, Lee, W.-S
• Format: Article
• Language: English
• Subjects: dielectric materials; homogeneous microwave heating system; magnetron output power controls; magnetrons; microwave generation; microwave generators; microwave heating; microwave power; Microwave technology; multimode microwave cavity; phase‐shifting WR‐340 waveguides; power control; power‐controlled phase‐shifting mode; system controller; uniform heating distribution
• ISSN: 0013-5194; 1350-911X; 1350-911X
• DOI: 10.1049/el.2019.0060

For homogeneous microwave heating in a microwave cavity with multiple 2.45 GHz microwave generators, power-controlled phase-shifting mode is proposed in this Letter. The proposed microwave heating system consists of a multimode microwave cavity in which dielectric materials are placed to be heated, four phase-shifting WR-340 waveguides for different phase excitation, four 1 kW magnetrons that produce microwave power at 2.45 GHz, and a power supply with a system controller for the magnetron output power controls. Using the proposed power-controlled phase-shifting mode, uniform heating distribution is achieved by reducing the hot and cold spots in the microwave cavity. The proposed experiments demonstrated that in comparison to a conventional mode with simultaneous multiple inputs, the proposed mode can achieve an improved heating uniformity of $\sim $∼64.4$\%$%.