Control strategy for an off-grid hybrid stirling engine/supercapacitor power generation system

Abstract

In this paper, a novel control strategy is proposed for a hybrid Stirling engine/supercapacitor power generation system functioning in isolated sites rich in sunshine. The controller should drive the system through its electrical part to satisfy the varying load demand and maintain the state of charge of the supercapacitor at an appropriate level. The system includes a thermodynamic machine (Stirling Engine) that drives a Permanent Magnet Synchronous Generator (PMSG). An appropriate power electronics is interfaced between this PMSG and the AC load to be supplied with the desired power. In order to meet the load transient demand, a supercapacitor is used and its delivered power is controlled by mean of a bidirectional DC/DC converter. As the testbed is under construction, a simulation scenarios are proposed to assess the efficiency of the proposed control architecture.