Network partition-based hierarchical decentralised voltage control for distribution networks with distributed PV systems

The penetration level of a PV system is often limited due to the violation of voltage variation introduced by the large intermittent power generation. This paper discusses the use of an active power curtailment strategy to reduce PV power injection during peak solar irradiation to prevent voltage violation so that the PV penetration level of a distribution feeder can be increased to fully utilize solar energy. When using the proposed voltage control scheme for limiting PV power injection into the study distribution feeder during high solar irradiation periods, the total power generation and total energy delivered by the PV system over a 1-year period are determined according to the annual duration of solar irradiation. With the proposed voltage control to perform the partial generation rejection of PV systems, the optimal installation capacity of PV systems can be determined by maximizing the net present value of the system so that better cost effectiveness of the PV project and better utilization of solar energy can be obtained.

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Centralized voltage control for distribution networks with embedded PV systems

Renewable Energy ◽

10.1016/j.renene.2014.11.015 ◽

2015 ◽

Vol 76 ◽

pp. 173-185 ◽

Cited By ~ 28

Author(s):

A. Cagnano ◽

E. De Tuglie

Keyword(s):

Voltage Control ◽

Distribution Networks ◽

Pv Systems

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Micro Static Var Compensator for Over-Voltage Control in Distribution Networks with High Penetration of Rooftop Photovoltaic Systems

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.839.54 ◽

2016 ◽

Vol 839 ◽

pp. 54-58 ◽

Cited By ~ 1

Author(s):

Piyadanai Pachanapan ◽

Phudit Inthai

Keyword(s):

Power Control ◽

Reactive Power ◽

Control Method ◽

Voltage Control ◽

Distribution Networks ◽

Static Var Compensator ◽

Pv System ◽

Reactive Power Control ◽

Pv Systems ◽

Dynamic Voltage

A micro static var compensator (µSVC) is introduced in this work to prevent the over-voltage problems in radial distribution networks with high number of rooftop photovoltaic (PV) connections. The µSVC is aimed to use in the PV system that has the fixed-power factor inverter, which cannot provide the active voltage controllability. The µSVC is a small shunt compensator installed parallel with the PV system and providing the automatic reactive power support to deal with the dynamic voltage variations at the point of common coupling. Two reactive power control methods, Q(P) and Q(V), can be employed into each µSVC depending on the location of PV systems. Moreover, the coordinated reactive power control among µSVCs, without communication system requirement, is presented for enhancing the Volt-Var controllability to the group of PV systems located in the same feeder. The dynamic voltage control performances are examined on simulation in DIgSILENT PowerFactory software. The results showed that the proposed control method can mitigate the rise of voltage level sufficiently.

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Optimal PV Allocation & Minimal tap-Changing Transformers Achieving Best Distribution Voltage Profile & Minimum Losses in Active Distribution Networks

Electrical Science & Engineering ◽

10.30564/ese.v1i2.1188 ◽

2019 ◽

Vol 1 (2) ◽

Author(s):

Hisham Soliman

Keyword(s):

Distribution Systems ◽

Reactive Power ◽

Voltage Control ◽

Distribution Networks ◽

Control Voltage ◽

Voltage Profile ◽

Voltage Standard ◽

Pv Systems ◽

Important Means ◽

Bus Voltage

In distribution systems, voltage levels of the various buses should be maintained within the permissible limits for satisfactory operation of all electrical installations and equipment. The task of voltage control is closely associated with fluctuating load conditions and corresponding requirements of reactive power compensation. The problem of load bus voltage optimization in distribution systems that have distributed generation (DG) has recently become an issue. In Oman, the distribution code limits the load bus voltage variations within ±6% of the nominal value. Several voltage control methods are employed in active distribution systems with a high share of photovoltaic systems (PV) to keep the voltage levels within the desirable limits. In addition to the constraint of targeting the best voltage profile, another constraint has to be achieved which is the minimum loss in the distribution network. An optimised solution for voltage of load busses with on-load tap-changing (OLTC) tarnsformers and PV sources is presesnted in this paper. This study addresses the problem of optimizing the injected power from PV systems associated with the facilities of tap-changing transformers, as it is an important means of controlling voltage throughout the system. To avoid violating tap-changing constraints, a method is depicted for determining the minimal changes in transformer taps to control voltage levels with distributed PV sources. The taps of a range + 5 to -15 %, can be achieved by tap-changing transformers. The OLTC operation was designed to keep the secondary bus within the voltage standard for MV networks.

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