Abstract: External energy Gatling machine guns are equipped with a type of special motor with a short startup time and high overload, and its improved power density is beneficial to the minimization and mechatronics design of weapon systems. The key characteristics of the electric motor, including fast starting speed, high torque, and short working time, are considered in the motor design. By analyzing the test data of the resistance torque and supply resistance torque of the automata under different radio frequencies, the motor design requirements are determined. Using Maxwell software, a 12-slot 10-pole electric motor model is developed. Results shows that the torque ripple can be reduced by optimizing the magnetic circuit structure, stator slot parameters, and the permanent magnet structure. The overload capacity and power density of the electric motor are improved by optimizing the core flux density at the working point and the saturation flux density of the stator core. Simulation results agree well with the experimental data. The maximum output power of the electric motor is 16.3 kW at 5 000 r/min, and the peak power density is 5.8 kW/kg. Experiments are conducted at a firing rate of 1 000-3 000 rounds/min. The automatic acceleration of the electric motor is completed within 200 ms. Upon reaching the rated firing frequency, the speed fluctuation of the electric motor is less than 10%, meeting the design requirements.

Key words: permanentmagnetmotor, externalenergyGatlinggun, startupcharacteristics, highpowerdensity