An integral-droop based dynamic power sharing control for hybrid energy storage system in DC microgrid

Abstract

Power sharing performance is a critical issue of hybrid energy storage system (HESS) in autonomous DC microgrid (MG). In this paper, a novel integral droop (ID) is proposed to mimic dynamic characteristics of the capacitor by using energy storages (ESs) with quick response. The main advantage of the proposed controller is that dynamic power sharing among ESs is automatically realized in the decentralized level. For a given HESS, ESs with the proposed ID enables to compensate fast power change while ESs with conventional voltage-power (V-P) droop provide low frequency components of power demand. With coordinated control between ID and V-P droop, high/low pass filters (LPF/HPF) are intrinsically formulated in HESS in order to obtain reasonable dynamic power allocations among ESs. Matlab/Simulink model of HESS is established for the verification of ID controller, in which the impacts of different ID coefficients on transient performances of the system are analyzed in detail. Finally, the effectiveness of proposed ID is experimentally validated on a HIL (hardware in loop) HESS platform.

Disturbance Observer Based Distributed Consensus Control Strategy of Multi‐Agent System with External Disturbance in a Standalone DC Microgrid

“…The DC link voltage deviates as load decrease or increase. By observing the SoC profile at node 5 during the disturbance in case II, the SoC variation is around 0.00039% and the obtained result from [17] gives 0.06% of SoC. From Figure 26 A, B, it is noted that the proposed leader follower controller reduces power stress on the battery during the disturbance as compared to leaderless approach…”

“…Let us consider the time delay, τ ij >0 on the communication network from agent j to agent i . A time delayed consensus law was investigated in [17]. The same delayed control law is incorporated to design the controller by considering the effects of communication time delay in the heterogeneous MG network.…”

“…Since the communication delay is introduced unavoidably it would worsen the performance of the controller. Generally, time delay varies from tens to hundred milliseconds [17].…”

Decentralised control strategy for hybrid battery energy storage system with considering dynamical state‐of‐charge regulation

“…Various HBESS topologies based on their connection topology have been proposed to optimise the system dynamic performance [21–23]. Based on lots of tests, the active connection topology was proved the most flexible topology; it not only can effectively coordinate the energy storages with different ramp rates but also has high system reliability.…”

A Low-pass Filter Method to Suppress the Voltage Variations Caused by Introducing Droop Control in DC Microgrids

“…Therefore, droop coefficient (or virtual resistance) plays a key role in current sharing. Many papers have been published on the study of droop control including decreasing circulating current [2], current sharing [3][4][5] and adaptive power distribution [6][7][8]. However, methods to select proper droop coefficients and analyze the impact to the previous designed closed loop are rarely discussed, which is important to study the dynamics of droop control and influence of system stability.…”