In order to achieve a state-of-charge (SOC) balance among multiple energy storage units (MESUs) in an islanded DC microgrid, SOC balancing and coordinated control strategy based on the adaptive droop coefficient algorithm for MESUs is proposed. When deviation significant, unit (ESU) with higher (or lower) set minimum value when discharging charging). The ESU controlled discharge charge) rated power, while other compensates remaining power demanded charging) greater than of individual ESU....

During the operation of DC microgrid, energy storage system plays an important role in supplying power difference between distributed generation unit and load maintaining voltage stability bus, recent years, hybrid technology has gradually attracted attention researchers. In this paper, a distribution control strategy (HESS) is studied. The droop based on virtual capacitor used for converter supercapacitor (SC) to realize HESS, improved solve problem that deviation bus caused by control....

Regarding PMSG-based wind turbine generation system, this study proposes a super-capacitor energy storage unit (SCECU) connected parallel to the DC-link of back-to-back converter enhance its high voltage ride through performance. The analysis operation and control for grid-side SCECU are conducted. Based on real-time digital simulators (RTDS), model with is developed, simulation results show that absorbs imbalanced inductive reactive power during period swell. based RTDS verify correctness...

Matrix converters (MC) have been considered for applications in renewable power generation and microgrids. However, similar to other electronic converter-interfaced systems, the MC-interfaced system cannot provide inertia or damping effect support grid's frequency voltage. To improve of distributed realize grid-friendly connection new energy generation, a virtual synchronous generator (VSG) control strategy suitable is proposed. Aiming at problem that traditional VSG be restored nominal...

This paper investigates the use of a static synchronous compensator (STATCOM) to mitigate voltage fluctuations and improve fault ride-through capability wind farm with fixed speed induction generators. In order assure STATCOM running safely reliably in both normal faulty conditions, novel control strategy which combines negative-sequence feed-forward conventional vector is proposed make negative sequence current zero effectively suppress overcurrent. The positive-sequence components at point...

Due to the randomness and intermittent characteristics of wind energy resources, it has a great impact on issues like voltage, frequency, system reliability so by power paralleling in grid directly. The novel control scheme synchronous compensator static (STATCOM) with hybrid storage (HESS) is proposed this paper. combination positive-and negative-sequence independent harmonic feed-forward compensation used for STATCOM mitigate voltage fluctuation, while double-loop adopted parallel type...

Regarding PMSG-based wind turbine generation system, this paper proposes a supercapacitor energy storage unit (SCESU) which is connected in parallel with the DC-link of back-to-back converter to enhance its high voltage ride through performance. The analysis operation and control for grid-side SCESU are conducted. Based on real time digital simulators (RTDS), model Hardware-in-the-Loop (HiL) platform developed, simulation results show that absorbs imbalanced inductive reactive power during...

Power variation, voltage fluctuation and flicker are critical issues related to the connecting wind turbines with squirrel-cage induction generators (SCIG) into grid. This paper investigates use of a static synchronous compensator (STATCOM) mitigate fluctuations improve power quality turbine SCIG. The experimental setup which contains STATCOM generation system (WTGS) SCIG is designed. control designed implemented based on fix-point DSP SEED-DEC2812. simulator composed motor (SCIM), converter...

In order to achieve the state of charge (SOC) balancing among multiple energy storage units in an islanded DC microgrid, SOC control strategy multi-energy based on a piecewise adaptive droop coefficient algorithm is proposed. The proposed dynamically adjusts according lithium battery deviation. When deviation large, adjusted so that has high (low) when discharging (charging) discharged (charged) with maximum power. Simultaneously, another controlled make up remaining power, accelerated....

The unbalanced grid voltage in wind farm with squirrel-cage induction generators (SCIG) can cause generator torque oscillations double frequency that reduce lifetime of drive train. In this paper, the mechanism and control strategy reducing using static synchronous compensator (STATCOM) is investigated for SCIG under voltage. oscillation analyzed based on its positive negative equivalent circuits as well power expressions. Mathematical formula relationship among sequence voltage, STATCOM...

In order to ensure the grid side converter and static reactive compensator in wind power systems run safely reliably under unbalanced voltage, it is basic requirement that phase frequency of positive sequence fundamental component voltage are obtained quickly accurately. Because dynamic behavior locked loop (PLL) based on synchronous reference frame dissatisfactory distorted improved PLL put forward not only extract unbalance eliminate effect voltages detection, but also suppress influence...

The DC microgrid has the advantages of simple internal structure, flexible control and no power quality issues related to frequency or reactive power. In an independent operation mode, energy storage units are required maintain stability system. However, multiple operated in parallel. It will have inconsistent state charge (SOC) problem due unreasonable distribution. To achieve SOC fast balancing be-tween different units, improved adaptive current distribution coefficient algorithm is...

Accurate estimation of the state charge (SOC) Lithium-ion batteries is critical technology for developing batteries. Aiming at problem that noise covariance UKF fixed, an adaptive algorithm proposed in this paper. The can estimate and correct characteristics system real-time, suppress possible filter divergence improve accuracy SOC. By analyzing simulation results constant discharge pulsed variable current pulse discharge, it proved filtering effect better higher.

With the increasing penetration of renewable energy integrated into power system and demand for flexible conversion, pulse width modulated (PWM) converter is being extensively used in many areas. Either working rectification inversion mode, PWM usually connected to grid. Appropriate control strategies are essential guaranteeing performance grid-connected converters various applications. There exist some adverse disturbances such as parameter variations, source load changes, measurement...