Abstract : Based on Kron's tensor electrical network theory, a digital simulation model of a frequency converter-brushless doubly-fed motor speed control system is established. This model, through secondary network transformation, can automatically handle time-varying topology networks composed of switching elements. Furthermore, by coupling with the brushless doubly-fed motor equations, a unified state equation for the system is established, enabling rapid simulation of the frequency converter-brushless doubly-fed motor speed control system. Keywords : Tensor method; brushless doubly-fed motor; simulation 1 Introduction Brushless doubly-fed motor speed control systems, with their advantages such as small frequency converter capacity, reliable performance, and low price, are increasingly attracting attention from scholars both domestically and internationally. This speed control system is particularly suitable for speed control of fans and pumps, and is a promising energy-saving speed control system. The stator of a brushless doubly-fed motor has two sets of windings. The power winding is connected to a constant-frequency, constant-voltage three-phase power supply, while the control winding is connected to the frequency converter. Due to the switching action of semiconductor devices in the converter, the brushless doubly-fed motor operates in a transient process, practically devoid of a steady state, making it difficult to adapt using conventional analysis methods. For this type of problem, the best approach is to use computer simulation to couple the motor equations with the inverter equations for solution. However, due to the switching action of semiconductor devices in the inverter, its topology changes, causing changes in its state equations, making simulation calculations cumbersome and time-consuming. This paper establishes a simulation mathematical model of the inverter-brushed doubly-fed motor speed control system based on Kronen's tensor electrical network theory. This model can automatically establish the system coupling equations composed of power electronic circuits and the brushless doubly-fed motor, overcoming the above difficulties and obtaining accurate and rapid results. [Full text of the simulation study of the inverter-brushed doubly-fed motor speed control system available for download.]