Implementation of a Two-Stage PV System Testbed with Power Reserves for Grid-Support Applications

This paper presents the implementation of a solar tracking algorithm for a small-scale, two-stage photovoltaic (PV) systems with power reserves. The work combines two algorithms found in the literature regarding the power curtailment of PV systems. The first is focused on providing a fast irradiance tracking capability, whereas the second is focused on achieving real-time maximum power point estimation (MPPE) when the system operates in power curtailment mode. By combining both algorithms, a technique providing fast tracking with real-time power reserves estimation is presented. First, a testbed of a two-stage PV system composed by a dc/dc boost converter cascaded with a single-phase inverter is built in Simulink. Next, simulations are carried to match the experimental data from the first algorithm to validate the testbed. Then, the second algorithm is combined with the first to create a testbed with potential to provide power reserves while maintaining fast irradiance tracking. Results demonstrate that the Simulink testbed can match the performance from experimental tests for PV system studies.