Filter-based PV power smoothing control for island hybrid energy systems with high PV penetration

Abstract

Hybrid energy system are a promising option considering low cost energy supply. The integration of renewable sources to diesel only systems allows for a reduction in diesel generator fuel consumption. However, significant issues with renewable power systems are their intermittency and unpredictability. This influence can be limited by an improved energy management strategy. State of the art strategies, which claim a low energy cost, are based on averaged photovoltaic (PV) data. Applying these methods to systems using real PV data results in an inefficient operation of the diesel generator and increased cost. In this paper, a new control strategy for the operation of diesel generators in systems with high (> 70%) PV penetration is proposed. This new operational strategy is based on a filter-based control, including a Kalman or Particle filter and a small storage to undertake the standby capacity of the diesel generator. Based on the filtered photovoltaic data, an optimal operating point for the diesel generator is identified. Simulation analysis using the load profile of a cargo complex shows that this method significantly improves the diesel generator operation by 50% reduction in cold starts compared to conventional hybrid energy management strategies. The proposed strategy also achieves up to 7% savings in cost of energy with high PV penetration.