SoC-based Controller of B4 Inverters for a Low-Cost PV System in Grid-connected Mode

Abstract

SoC-based control unit for B4 inverters in a cheap grid-connected Photovoltaic (PV) system is proposed in this paper. Because the inverter is the main element of Photovoltaic module, we utilized the B4 one here for decrement of entire expenditure of Photovoltaic system. This paper also coupled the Photovoltaic system to the main grid via IGBT switches for removing the bulky transformers. Besides, in order to inject the real energy to the main grid, this kind inverter is able to compensate to make up the real power and mitigate the harmonics related to the non-linear loads. Instead of the conventional PV systems on which a DSP processor is used to control the B4 inverter, we applied a zynq-7020 SoC-base control unit for effective control of the B4 inverter. Several characteristics of such control units such as dedicated low power and fast 32bit×32bit multipliers, with modified algorithm, enable the application of the required control methods. The operation of the proposed control unit in a PV system is implemented on zynq-7020. Implementation of the control unit in the SoC zync-7020 is the main contribution of this paper. Comparison with the conventional DSP-based control systems, TMS320F28335 DSP processor, demonstrated the high efficiency of the proposed SoC-based control unit for B4 inverters.