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Belt conveyors offer advantages such as reliable operation, the ability to transport over long distances in large quantities, as well as reliability in operation and ease of automation and centralized control. They are key devices in the mechatronic technologies and equipment used for efficient coal mining today. With the development of efficient mining technologies, belt conveyors are evolving toward larger sizes, featuring longer distances, higher capacity, faster belt speeds, and greater power. Therefore, the drive system of modern large-scale belt conveyors employs a multi-motor, multi-point drive approach, which can significantly reduce the strength required of the belt, lower the production costs for enterprises, reduce the peak voltage in the power grid, and also contribute to the miniaturization of the conveying equipment, thereby improving the economic efficiency of these enterprises. Due to the viscoelastic properties of the conveyor belt and various types of resistance, the control system for the drive mechanism of a belt conveyor is a complex electromechanical system. There is a key issue here, namely the stable power control of belt conveyors. Given the need for coordinated control in multi-motor driven belt conveyors, the master-slave control technique is employed for multiple frequency converters that are used for frequency conversion adjustments. This approach enables power balance among the motors, helps to reduce the impact of starting currents, lowers production costs for enterprises, and improves the productivity of coal mines. Master-slave control of belt conveyors refers to a control method in which the relevant parameters of one of several drive units that need to be synchronized are used as targets for the other drive units to follow, thereby achieving synchronized operation. That is, one motor in the drive system is selected as the master motor, while the remaining motors serve as slave motors. The host uses the values specified by the user, such as the set speed, as reference values, and tracks the system’s specified values during operation ； The slave no longer tracks the system setpoint; instead, it uses the output values such as the master’s torque as its reference values, and tracks the relevant parameters of the master during operation. In this way, the multiple motors do not each track the system’s set value independently; instead, the subordinate motors follow the lead motor, thereby enabling synchronized and coordinated control as well as power balance among the motors. In multi-motor master-slave control systems for belt conveyors, the transmission system is driven by several drive units, and the motor shafts of these drive units are connected to each other in different ways. Its connection methods are divided into two types: rigid connection and flexible connection, and this article mainly analyzes the rigid connection method. A rigid connection refers to the connection between several different motor shafts through hard coupling methods such as reducers, gears, and chains. In this connection method, as long as one of the motors is operating, the other motor or motors will also operate passively; the mechanical connection between the master and slave units ensures speed synchronization.