Design of an Electric Motor Control System on a Milling Machine Sled Model UH-IF Series No. 1508 Based on Variable Frequency Drive (VFD)

Abstract

The UH-I.F Series No. 1508 milling machine in the Production Laboratory of the Mechanical Engineering Department at Politeknik Negeri Manado has an electric motor control system on the carriage that no longer functions optimally, resulting in less flexible and inefficient speed regulation, reduced machining accuracy, and diminished quality of student practical activities. This study aims to design and implement an electric motor control system based on a Variable Frequency Drive (VFD) to replace the outdated system, enabling precise, energy-efficient, and user-friendly motor speed control. The method involved analyzing the existing system, selecting components, configuring VFD parameters, modifying the motor connection from star (Y) to delta, and installing a manual control panel with a potentiometer. The research was conducted at the Manufacturing Workshop of the Mechanical Engineering Department from March to July 2025. The results show that the VFD-based control system operates effectively, providing more accurate, responsive, and stable speed control according to operational needs while restoring the milling machine’s performance to support practical learning. In conclusion, the application of a VFD to the carriage motor of the milling machine improves energy efficiency, extends machine lifespan, and offers speed control flexibility that conventional systems cannot provide.