This paper presents a new power management algorithm for an off-grid photovoltaic system. The algorithm uses linear algebra control and includes DC Bus voltage control. To evaluate the effectiveness of the proposed controller, computer simulations are conducted on a standalone system configured as an Off-Grid system. Simulations incorporate models of the photovoltaic array and batteries. The results show that the linear algebra control performs well and is reliable in power management. Therefore, the proposed system can supply energy to the load even with abrupt changes in solar radiation, temperature, and load dynamics.