Search

This paper proposes an optimal energy management of grid-connected PV-Diesel-Battery power system using a newly developed supervision algorithm. The main advantage of the proposed control technique is to reduce the size of the power system, lower the power cost and ensure fuel economy, which can be achieved by using the concepts of: two-level control strategy, high-priority and low-priority loads, bidirectional power flow to and from the utility grid, and energy selling in timely manner. To examine the effectiveness of the proposed control technique, MATLAB simulations are carried out under a challenging scenarios, namely irradiance of typical day, two variable loads with high and low priority and one battery charge cycle. The obtained results confirmed the effectiveness of the control technique in general and the management algorithm in particular in satisfying the load power needs and selling/buying the power to/from the utility grid in the right time, while protecting battery from the overcharging and the deepdischarging.

Over the past few decades, the fast development of high switching frequency power electronics drives towards wider application of voltage source inverters in AL power generation. Thus, a modulation technique with less total harmonic distortion, fewer switching losses, and wider linear modulation range, was needed. An analyze of the potential variation of middle point for three level inverter and based on redundant small vectors compensation, we have proposed the action time correction methods for the basic voltage vectors and the original fundamental voltage vector This study, afford a contribution to the problem of neutral-point voltage balancing in three-level NPC converter. That showed the three-level neutral point potential fluctuations can be suppressed effectively by the middle point potential compensation algorithm. MATLAB was used to build a simulation model for analysis.