Active power management in a low-voltage islanded microgrid

Abstract

The growing electricity demand and scarcity of energy sources are the driving force of exploration of the renewable energy sources. However, uncertain energy production of these sources makes difficulties in their control and operation with or without a grid utility connection. This paper proposes a novel power control strategy which employs a voltage band in the DC-link voltage to maintain voltage stability and thereby improve the power quality during temporary disturbances in a network. It is applied to act as an inverter's inertia and obtain maximum benefit from the storage system, based on the features of a DC busbar to avoid a voltage limit violation. It also presents a demand dispatch strategy based on a client's terminal voltage, which avoids the complexity of communication lines, for balancing the network power during power shortages. The developed control algorithm is tested on an IEEE 16 bus test feeder with multiple DG units and from the results it is found that the proposed control methods provide effective control of the voltage and power quality during transient conditions and scarce power generation.

Evolution of Microgrids with Converter-Interfaced Generations: Challenges and Opportunities

“…In [74], an ESS used as an inertia energy to regulate the frequency of a microgrid has the capability to seamlessly transfer. A capacitor employed to decouple a converter's input power from the boost converter's output can be used as an inertia of the converter to control the terminal voltage [1]. In order to apply the well-established conventional control algorithms/theories to converter-interfaced generators, the concept of a synchronverter, which mimics the behaviours of conventional synchronous ones over short periods of time for the integration of RESs in a distribution network, is proposed in [75].…”

Evolution of Microgrids with Converter-Interfaced Generations: Challenges and Opportunities

“…In [73], an ESS used as an inertia energy to regulate the frequency of a microgrid has the capability to seamlessly transfer. A capacitor employed to decouple a converter's input power from the boost converter's output can be used as an inertia of the converter to control the terminal voltage [1]. In order to apply the well-established conventional control algorithms/theories to converter-interfaced generators, the concept of a synchronverter, which mimics the behaviours of conventional synchronous ones over short periods of time for the integration of RESs in a distribution network, is proposed in [74].…”

“…These types of microgrids can be constructed in both residential and commercial premises, such as university campuses, hospitals, data centres, communities, industries and shopping malls. Remote microgrids: These microgrids are constructed in remote areas where a grid utility has no access for geographical reasons, such as military installations, islands and hilly areas [1,111]. As these microgrids, also known as islanded microgrids, are not connected to the grid supply, they do not require rules and regulations like urban microgrids.…”

“…Currently, there is a shift in power generation from conventional energy sources to renewable ones for a number of reasons. These include mitigating the effects of climate change and the gradual depletion of energy sources (coal, gas and oil), dealing with the steadily increasing consumption of energy, satisfying the need for local economic and social development, reducing power losses over long transmission lines and decreasing the amount of investment required to construct new power transmission lines [1,2]. Figures 1a and 1b depict investments in solar and wind power, and their integration in generating power around the world [3].…”

Modified PSO Algorithm for Real-Time Energy Management in Grid-Connected Microgrids

“…The penetration of intermittent renewable energy sources (RESs), such as wind and solar, into existing distribution networks has increased significantly to meet the growing electricity demand and fulfil the target of reducing greenhouse gas emissions [1,2]. However, these RESs, depending on weather conditions and time of day, are stochastic in nature, resulting in variable power generation.…”