GaN器件具备更快的开关速度，可以降低噪音，显著减小伺服驱动器体积，但电磁干扰(EMI)问题更加突出。采用随机载波频率调制策略(RCFPWM)可有效抑制EMI，但载波频率随机化后使转矩脉动更为剧烈。因此，提出一种基于Markov链的混合载波频率调制策略(Markov-HCFPWM)，采用混合载波频率调制减小相邻开关周期的载波频率差值，采用Markov链使局部平均载波频率接近期望值。仿真和试验结果表明，所提策略相较RCFPWM策略在有效抑制EMI的前提下也可减小转矩脉动。

GaN devices have faster switching speeds that reduce noise and significantly reduce servo-driver size, but electromagnetic interference (EMI) issues are more pronounced. The random carrier frequency modulation strategy (RCFPWM) can effectively suppress EMI, but the torque ripple is more severe after the carrier frequency is randomized. Therefore, a hybrid carrier frequency modulation strategy based on Markov chain (Markov-HCFPWM) is proposed. This strategy uses mixed carrier frequency modulation to reduce carrier frequency difference between adjacent switching cycles, and uses Markov chain to make local average carrier frequency close to the expected value. The simulation and test results show that compared with RCFPWM strategy, the proposed strategy can reduce torque ripple on the premise of effectively suppressing EMI.