The magnetic particle dynamometer is composed of a stator, a solid rotor, a magnetic coil, a magnetic particle medium, a bracket, a bottom plate, etc., when the internal coil of the magnetic particle dynamometer passes through the current, a magnetic field is generated, so that the internal magnetic particles are arranged into magnetic chains according to the magnetic field lines, and the pulling force generated by the magnetic particle chain becomes the resistance to prevent the rotor from rotating, and the force is the load moment. The load torque can be changed by changing the excitation current. It is suitable for occasions with high torque and low speed, such as constant torque with load starting, asynchronous motors, reducers, hydraulic motors, mining machinery and other power machinery. Features: Simple structure, compact, large braking torque Good stability, fast dynamic response Long service life, easy maintenance