Power Management Strategy Based on Virtual Inertia for DC Microgrids

Abstract

This paper presents a power management strategy (PMS) to control the power flow in a DC microgrid operating in the grid-connected mode. The microgrid model is composed of the AC utility grid interfaced with a voltage source inverter operating as a grid-forming converter (VSC), an energy storage system (ESS) formed by a battery bank and a bidirectional DC-DC converter operating as a grid-supporting unit, a distributed generation acting as a grid-feeding unit, and the customer loads with strict voltage regulation. The power management technique applies a virtual inertia concept together with a state of charge-based management function to regulate the charging and discharging process of the battery bank according to the DC microgrid power flow. Thus, high-rate peaks of power are avoided, which improves the ESS life cycle. With the proposed PMS, an autonomous power flow is achieved inside the DC microgrid, while the AC utility grid focuses exclusively upon forming the DC bus and processing the surplus or shortage of power. In addition, the proposed strategy simplifies the communication link between the grid inverter and the ESS, since the VSC power is the sole information exchanged. The experimental results show that the proposed PMS is reliable, leading to high ESS performance and power flow control within the DC microgrid, without degrading the DC bus voltage.

Modeling and Predictive Control of Shipboard Hybrid DC Power Systems

“…As an alternative controller proposed by this paper as shown in the duty cycle calculation block in Fig. 3, the predicted v dc (k + 2) in ( 10) can be filtered and used to control the DC-DC converter by calculating i bat,ref (k + 1) to compensate the voltage deviation from the battery output voltage reference (v dc,bat,ref ) given by the high-level controller in (18) as…”

“…The proposed control method has a voltage compensation function by the battery. This function is realized by assigning reference battery current in consideration of the voltage control as specified in (18). Therefore, the charging/discharging power of the battery should be determined accordingly.…”

“…In the previous studies, a single energy source represented by one AFE rectifier with a resistive load is normally considered, and PI control method that comprises an inner (current) and outer (voltage) control loop is prevalently used for ESS control as a conventional method [18]. In the shipboard DC power systems, the tight control of the heavy power loads and switching operation between the multiple energy sources can cause serious DC voltage fluctuations which can result in a blackout in the entire power system, so the dynamic load profile should be considered as a constant power load (CPL).…”

Design and Implementation of a Solar Pv Microgrid: A Case Study of Palestine

“…Many countries in the world encourage applying the microgrid systems by assigning certain policies and in corporation with research institutes, universities and private sectors. However, there are two main standards for microgrids issues: IEC 61850-7-420 titled by "communications standard for distributed energy resources", and IEEE Std 1547.4™-2011 which is titled by " IEEE guide for design, operation, and integration of distributed resource island systems with electric power systems" [3][4][5][6].…”

Revitalisasi Pembangkit Listrik Tenaga Surya (Plts) Pada Sistem Microgrid Pulau Tomia

“…Terdapat beberapa peneliti yang sudah membahas sistem microgrid, dimulai dari pemanfaatan baterai sebagai penyimpan energi (Mckeon et al, 2013;Serban et al, 2013), fungsi baterai sebagai penyangga frekuensi maupun tegangan jika terjadi perubahan yang signifikan pada pembangkit dan beban (Bae et al, 2012;Xia et al, 2019), pembahasan sistem kontrol pengaturan daya pada inverter (Che et al, 2015;Jiang et al, 2007;Patarroyo-montenegro et al, 2017;Wang et al, 2011;Zhao et al, 2015;Liu et al, 2019), serta manajemen energinya (Dong et al, 2020;Jos et al, 2020). Namun, belum ditemukan artikel yang membahas mengenai proses revitalisasi suatu aset microgrid yang sedang mengalami permasalahan.…”