## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Enhancing microwave oven performance and transformer quality through efficient high voltage transformer cooling

**ABSTRACT**

This paper describes a method and device for effectively cooling a high voltage transformer inside a microwave oven, with the aim of swiftly removing heat generated during operation, hence improving both the microwave oven's and the transformer's performance and quality. The device incorporates corrugated tank surfaces, electrical connection lines with protrusions, and epoxy to prevent cooling oil leakage. The transformer is inserted into a designated tank and sealed to separate the coil and core from the outside environment, allowing for better cooling and protection against electrical shock. Additionally, an oil is injected to absorb heat generated by the high temperature of the core and coil. The effectiveness of this method is validated through the finite element method and computational fluid dynamics techniques. Numerical analysis revealed a significant decrease in the maximum temperature rise of the transformer by around 44.2°C. This finding suggests that transformer oil cooling is a more effective method for controlling temperature rise in microwave ovens compared to traditional cooling methods.

**KEYWORDS**

PAPER SUBMITTED: 2023-10-21

PAPER REVISED: 2024-03-01

PAPER ACCEPTED: 2024-03-11

PUBLISHED ONLINE: 2024-05-18

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