Buck converter is a kind of converter device with high efficiency, wide adjustable output voltage, small loss, small size and light weight. Its circuit has nonlinearity and will exhibit abundant nonlinear phenomena with the change of circuit parameters, resulting in unstable output voltage and being susceptible to load and external disturbances. Therefore, a control method based on Extreme Learning Machine (ELM) combined with a proportionalintegral-derivative (PID) controller is proposed in this paper and used for output voltage control of buck converter. Firstly, the mathematical model of buck converter in Continuous Conduction Mode (CCM) is established by the state space averaging method. Then the PID tuning algorithm is designed in combination with ELM, and the stability analysis of the model is carried out. Finally, the simulation experiment is carried out under different disturbances. By comparing with the open-loop control strategy, the effectiveness of the proposed ELM-PID control strategy is verified, indicating that the proposed method can achieve the stability of output voltage and good dynamic response.

降压转换器是一种效率高，输出电压可调，损耗小，体积小，重量轻的转换器。其电路具有非线性特性，并且随着电路参数的变化将表现出丰富的非线性现象，从而导致输出电压不稳定，并容易受到负载和外部干扰的影响。因此，本文提出了一种基于极限学习机（ELM）结合比例积分微分（PID）控制器的控制方法，并将其用于降压变换器的输出电压控制。首先，通过状态空间平均法建立了连续导通模式下降压变换器的数学模型。然后结合ELM设计了PID整定算法，并对模型进行了稳定性分析。最后，仿真实验是在不同干扰下进行的。通过与开环控制策略的比较，验证了所提出的ELM-PID控制策略的有效性，表明所提出的方法可以实现输出电压的稳定性和良好的动态响应。