Introduction  The paper aims to realize constant voltage or constant current microgrid control under different types of load conditions.

  Method  A simple DC microgrid was built by using a microcontroller and other circuit components, a closed-loop PID controller was used to control the circuit, and a Simulink simulation model was built at the same time, and the PID parameters were designed and simulated in advance using the simulation model. It could make the PID parameter setting reasonable, reduced the hidden danger of hardware in the microgrid, and ensured the normal operation of each part of the circuit in the process of hardware construction.

  Result  It can be seen from the experimental data that the output value error can be guaranteed to be less than 2% in terms of constant voltage or constant current output.

  Conclusion  The feasibility of using a microcontroller to control the voltage and current of the microgrid is demonstrated in this paper.