Abstract
This paper presents the experimental verification of a 2 kW battery energy storage system (BESS). The BESS comprises a full-bridge bidirectional isolated dc-dc converter and a PWM converter that is intended for integration with a photovoltaic (PV) generator, resulting in leveling of the intermittent output power from the PV generator at the utility side. A phase-shift controller is also employed to manage the charging and discharging operations of the BESS based on PV output power and battery voltage. Moreover, a current controller that uses the d-q synchronous reference frame is proposed to regulate the dc voltage at the high-voltage side (HVS) to ensure that the voltage ratio of the HVS with low-voltage side (LVS) is equivalent to the transformer turns ratio. The proposed controllers allow fast response to changes in real power requirements and results in unity power factor current injection at the utility side. In addition, the efficient active power injection is achieved as the switching losses are minimized. The peak efficiency of the bidirectional isolated dc-dc converter is measured up to 95.4% during battery charging and 95.1% for battery discharging.
Highlights
Current grid codes for low-voltage grid-connected PV systems consider a low PV penetration and in many countries stipulate the regulation for anti-islanding and total harmonic distortion of injected current to be less than 5%
This paper describes a battery energy storage system (BESS) that consists of a battery unit, a bidirectional isolated dc-dc converter, and a PWM converter that can be applied to regulate the output power of a PV system
The BESS system is designed to supply a constant power of 2 kW into the grid at the point of common coupling (PCC)
Summary
Current grid codes for low-voltage grid-connected PV systems consider a low PV penetration and in many countries stipulate the regulation for anti-islanding and total harmonic distortion of injected current to be less than 5%. Battery energy storage systems could be employed to absorb active power from PV during the FRT conditions. A bidirectional isolated dc-dc converter with highfrequency galvanic isolation is one of the technologies that enables the integration of energy storage devices such as batteries and electric double-layer capacitors to the utility grid [2,3,4,5,6]. The high-frequency galvanic isolation increases the power density and the reliability of the energy storage system. The performance of the latest-generation IGBT improved in device switching losses. The authors of [5] showed that, with the usage of silicon carbide MOSFETs, the performance of the bidirectional isolated dc-dc converter is greatly improved as compared to the dc-dc converter using siliconbased switching devices.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
