Stand-alone wind system with Vanadium Redox Battery energy storage

Abstract

Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a standalone wind energy system attractive. This paper proposes the integration of a VRB system with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge controller, transformer, inverter, ac loads and VRB (to store a surplus of wind energy and to supply power during a wind power shortage). The main purpose is to supply domestic appliances through a single phase 230V, 50Hz inverter. Simulations are accomplished in order to validate the stability of the supply. Figure 1. A vanadium redox flow battery I.

Design of a Bidirectional Energy Storage System for a Vanadium Redox Flow Battery in a Microgrid with SOC Estimation

“…The traditional method for SOC estimation is based on the equivalent circuit of the VRB, which is shown in Figure 3 [16,17]. In Figure 3, the stack voltage Ustack is imitated by a voltage-controlled source, which is influenced by the value of the SOC and the cell voltage of the VRB, as shown in Equation (3).…”

“…However, most of these are based on how to establish an objective function of a VRB for describing the performance characterization of a VRB. In [14][15][16][17][18], an equivalent model of a VRB was comprehensively introduced, to obtain the operational characteristics of a VRB. In [19,20], a comprehensive equivalent circuit model of a VRB was presented for system level analysis, in which the concentration over potential is modeled as a function of flow rate, in an order to determine determine an appropriate variable flow rate.…”

Hybridization of Energy Storage Systems for electric transportation by means of bidirectional Power Electronic Converters

“…As the control of SDESS bidirectional boost converter is to maintain the DC link voltage constant. A typical cascaded control scheme is used, being the outer loop the DC link voltage control and the inner loop the inductor current control [6], [23]- [27] as shown in Fig. 5.…”

Control Structure for Single-Phase Stand-Alone Wind-Based Energy Sources

“…Thus, an adequate controlling method, based on Maximum Power Point Tracking (MPPT), must be used, in order to maximize the electric output power and to adjust the generator speed [12], [13], [26].…”