Abstract: As the structure of DC microgrid becomes more and more complex and there are more and more operating conditions.However,the existing stability analysis methods are mainly aimed at single operating condition. Therefore,it is necessary to study general stability analysis methods suitable for the system operating in multiple operating conditions. Firstly,the impedance model of each unit of optical storage DC microgrid is established according to different operating conditions,and the boundary conditions of load power and bus capacitance are derived by the method of steady state analysis combined with Routh criterion. Secondly,by redefining the loop gain expression of the system,a more general stability criterion based on BVCC and BCCC is obtained,and the system stability under various operating conditions is analyzed by using this criterion. With the help of the obtained boundary conditions,appropriate system parameters are calculated using the operating conditions with low stability margin to ensure that the system can be in stable operating state. Finally,the system simulation model is built,and the accuracy of the boundary conditions and stability analysis conclusions is verified by the simulation analysis of three typical working conditions.