Abstract: Vector control technology, with its wide speed range and excellent dynamic and static response performance, has become the preferred high-efficiency control strategy for electric drive systems. This paper adopts a model-based minimum loss control method, which reduces the iron loss of the motor by controlling a variable in the loss function, thereby achieving a balance between copper loss and iron loss and realizing the optimal efficiency of the asynchronous motor under light load steady state. Simulation results show that this method has fast control speed, good stability, and requires no additional hardware investment. Keywords: induction motor; vector control; efficiency optimization; loss minimization controller Abstract: The vector control technology, with the advantages of a wide velocity-adjusting range and dynamic and static response quality, has become the top choice for the high-efficiency control in the current electricity-powered system. The dynamic mathematic model founded on the synchronous rotating coordination was induced with the consideration of core loss. Based on which, a minimum control method based on the model was applied (that is, controlling a variable in the waste function) to reduce the core loss of the motor and balance the core loss and copper loss. Then, the optimal efficiency of the induction motor under the partial load and stable status was realized. Simulation results show that this method can achieve high control velocity and good stability without increasing costs. Key words: induction motor; vector control; efficiency optimization; loss minimization controller 1 Introduction Asynchronous motors, with their many advantages, have gradually replaced DC motors and are widely used in many fields[1]. In my country, the electricity consumption of asynchronous motors accounts for 60% of the total electricity consumption in the country, driving more than 90% of the moving machinery powered by electricity. Therefore, studying the energy-saving technology of asynchronous motors and improving their operating efficiency is of great practical significance for saving energy and controlling environmental pollution [2]. Vector control is an advanced and high-performance motor speed regulation method, which plays a positive role in saving energy and reducing losses of asynchronous motors. The standard vector control method adopts a constant flux control strategy in the constant torque speed regulation range. However, under light load, the system will inevitably cause excessive iron core loss when operating at the rated flux, resulting in a decrease in motor efficiency. In other words, the high-performance vector control frequency conversion drive system is not optimal in terms of efficiency [3,4]. If vector control is combined with the principle of optimal efficiency, the high-efficiency operating range of asynchronous motors can be effectively extended [5]. This paper uses model-based minimum loss control (LMC) to conduct an in-depth study on the efficiency optimization problem of vector control asynchronous motors under light load steady state. For details, please click: Research on model-based vector control asynchronous motor efficiency optimization control.