Model-Free Predictive Control of a Wind-Battery DC Microgrid Supplying a Surface Water Heat Pump

Abstract

The decarbonization of heating systems requires efficient integration of renewable energy sources (RESs) for heat pump (HP) applications. This digest presents a hybrid DC microgrid integrating a 35 kW wind turbine (WT) and a 30 kWh battery energy storage system (BESS) to supply a surface water heat pump (SWHP) through a regulated DC bus. Unlike conventional model-based approaches, the proposed strategy employs model-free predictive control (MFPC) to control the inductor currents of both the WT and BESS converters without requiring an accurate system model. The WT controller tracks the reference current derived from the wind power demand, while the BESS controller manages bidirectional current flow according to the DC bus voltage and battery state of charge (SoC). Simulation results demonstrate stable DC bus regulation with a maximum deviation of 7 V and accurate current tracking errors below 4 A, ensuring continuous and reliable operation of the SWHP.