Power management and coordinated control of standalone active PV generator for isolated agriculture area-case study in the South of Algeria

Abstract

This paper aims to elaborate a local energy management and coordinated control of a 15 kW Standalone Active PV Generator (SAAPG), dedicated to the electrical supply of a remote farm in southern Algeria. The SAAPG is composed of four sources: Photovoltaics, Lead Acid Batteries, Ultra-capacitors, and Diesel generators (DGs); all these sources are coupled together in the DC-link (VDC-ref = 700 V). This agricultural area is mainly equipped with unpredictable high dynamic (transient) loads composed of two cold room compressors, an immersed pump and a watering pump. Unlike usual, a DC side coupling structure of the DG is proposed in this paper in order to ensure two dominant advantages: the first one is to slow the dynamics of the DG output power, which will be imposed by the DG boost converter instead of the load (like AC side coupling), allowing a low maintenance frequency in the diesel engine by reducing thermo-mechanical stresses in diesel engine cylinder heads due to transients. The second one guarantees both efficiency and cost effectiveness of the system by operating the DG near to its rated power in either transient or steady state conditions, and thus, such an oversizing of the DG will be avoided unlike the AC coupling case. The four power sources are managed in coordination, according to their dynamics, to maintain the DC-link voltage value regulated around its reference. A three-phase DC-AC PWM converter operates independently considering the DC link as a fixed DC source voltage in order to power supply AC loads.

Climate-Smart Agriculture in African Countries: A Review of Strategies and Impacts on Smallholder Farmers

“…Smallholder farmers in Algeria are currently required to raise agricultural production while using fewer resources (such as less energy and more water) and under more constraints (e.g., an increase in temperatures, soil salinity and desertification). A number of CSA practices have been initiated and implemented, such as water saving, construction of dams and hill reservoirs, fight against erosion and desertification, anti-drought programs, protection and rehabilitation of steppe lands and preservation and extension of forests [43][44][45][46][47][48]. Here are some examples of climate-smart innovations in the agricultural, livestock and forestry sectors, financial resources and policy evolution.…”

Photovoltaic-Battery-Ultracapacitor-Diesel Hybrid Generation System for Mobile Hospital Energy Supply

“…In the same context, Ref. [23] proposes a coupling structure of the DG on the DC bus side to slow down the power dynamics produced by the DG and ensure the efficiency and profitability of the system by operating the DG around its rated power. A voltage and frequency control strategy is developed in [24] for a renewable power generation system.…”

Energy Conversion System based on Photovoltaic-Battery-Ultra Capacitor-Diesel Sources for a Mobile Hospital

“…In [34], proposes a method for controlling the power balance of a multi-source micro-grid hybrid system to meet the DC load power demand with reliability and DC bus voltage stabilization. In the same context, [38] proposes a coupling structure of the DG on the DC bus side to slow down the power dynamics produced by the DG, which will be imposed by the inverter and ensure the e ciency and pro tability of the system by operating the DG around its rated power, on the other hand [36] proposes a voltage and frequency control strategy for a system with high intermittent renewable power generation.…”

“…Indeed, in [35] and [37], a transition control strategy between the connected and disconnected modes of the grid was proposed for a three-phase voltage source based on the calculation of reference powers and a virtual impedance control strategy to achieve e cient power distribution in the hybrid energy storage elements, where the battery provides steady-state power and supports only transient power uctuations respectively or the synchronization problem has been well studied in both modes. In [38], a clear control methodology for the transition between the different modes was developed.…”