Design of a Speed Regulation Control System for Mine Hoists Based on PLC

The mine hoist, as a critical large-scale equipment in mining production, plays a pivotal role in operational efficiency and safety. To address the prevalent issues in small- and medium-sized mines—such as poor speed regulation performance, high failure rates, and excessive energy consumption in AC wound-rotor motor systems with series resistance—this study integrates the robust control capabilities of Programmable Logic Controllers (PLCs) with variable-frequency drive (VFD) technology. An S-curve speed control strategy is employed, wherein the PLC generates the speed reference curve via software programming, transmitting it to the VFD through analog input interfaces to regulate motor speed during startup, constant-speed operation, deceleration, crawling, and stopping. Experimental results demonstrate that this design significantly reduces hardware components and control wiring while markedly enhancing system stability and reliability.