• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1333-1335
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• 2005

STATCOM has many advantages rather tan SVC at a view point of a continuous controllability of reactive power and response time of reactive power compensation In this paper, 30kVA STATCOM for compensation of low voltage industrial loads is designed and its operation characteristics is analyzed and verified by simulation.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.180-181
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• 2017

Recently as distributed source has increased, the distribution system has changed from unidirectional power flow to bi-directional power flow. This power flow causes the PCC voltage variation, which can adversely affect voltage sensitive loads. In this paper, the relation between the active power, reactive power and PCC voltage of the distributed source is analyzed, and the PCC voltage control scheme by reactive power compensation is proposed in the distributed source itself. In addition, limitations and conditions according to the standard for interconnecting distributed resources are specified and verified through simulation.

• Journal of Power Electronics
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• v.5 no.4
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• pp.329-334
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• 2005

The DSTATCOM(Distribution Static Synchronous Compensator) is one of the Custom Power Devices that can regulate voltage. The DSTATCOM operates as a shunt connected static var compensator whose capacitive or inductive output current can be controlled independent of the system voltage. The magnitude of the compensated voltage is limited by characteristics of the system and the load. Compensation capability of the DSTATCOM which can inject 1 MVAR reactive power was simulated by EMTDC under several conditions. This paper analyzes the effect of the DSTATCOM's compensation considering the length and kind of distribution line, the power factor and magnitude of the load, and the duration and magnitude of the voltage variation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.6
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• pp.330-335
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• 1999

This paper proposed the p-q-r coordinate system where the instantaneous active power p, and the two instantaneous reactive powers qq, qr were defined. The three power components are linearly independent, so the compensation for the two instantaneous reactive powers leads to control the two components of the current space vector. With the theory, the neutral current of a three-phase four-wire system can be eliminated by only compensating the instantaneous reactive power using no energy storge element.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.6
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• pp.82-89
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• 2011

Reactive power support is considered to be necessary for dealing with a voltage stability issue with wind turbine system employing squirrel-cage induction generator(SCIG). This paper analyses steady-state characteristics of the SCIG wind turbine system by simulating torque-slip characteristics of SCIG with respect to variations of interconnecting network strength and generator terminal voltage. It also presents dynamics analysis of SCIG wind turbine system on Simulink to investigate the impact of static var compensator(SVC) and static synchronous compensator(STATCOM) on transient stability enhancement. It analysed transient stability with varying fault duration times and compared the transient stability characteristics with varying rated capacities of SVC and STATCOM. It is shown that the STATCOM has a better performance and reactive power support compared to SVC.

• Plant Journal
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• v.17 no.2
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• pp.48-53
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• 2021

In the case of a 900 MW combined cycle power plant, most of the load on the site is a rotating device and is operated at a low power factor, and the power factor decrease increases the reactive power, which causes the efficiency of the device to be consumed and unnecessary unnecessary power consumption. This study intends to present the results by installing and operating a reactive power compensation device that absorbs and removes reactive power, which is a solution to this problem, on a 6.9 kV on-board bus. As a result of application of this system, first, it was confirmed that the power factor of the rotating machine was improved to 0.22 and the load power in the house was reduced by 1.4%, and the thermal efficiency of the generator was increased by 0.1% and the power generation power by 810 kW. Next, it was confirmed that the cost of construction and operation can be reduced in the future due to economic feasibility, with a decrease of 200 million won/year in electricity loss compared to 1.5 billion won in investment, an increase of 1 billion won/year in sales, and a one-year capital recovery period.

• Journal of Power Electronics
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• v.13 no.5
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• pp.854-860
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• 2013

The voltage variation problem at the point of common coupling (PCC) in a grid-connected wind turbine is investigated. The voltage variation problem is one of the most frequent power quality issues for the grid connection of large amounts of input power in a weak grid. Through the simplified modeling of the wind turbine and power network, the magnitude of PCC voltage variation is calculated by using the equivalent circuit parameters and output power of the wind turbine. The required amount of reactive power that can compensate the voltage variation is also presented analytically by using the vector diagram method. The proposed calculation and compensation method of the PCC voltage variation is verified by computer simulations and experiments.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.1
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• pp.65-76
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• 2024

With the recent activation of the offshore wind power industry, there has been a development of power plants with a scale exceeding 400MW, comparable to traditional thermal power plants. Renewable energy, characterized by intermittency depending on the energy source, is a prominent feature of modern renewable power generation facilities, which are structured based on controllable inverter technology. As the integration of renewable energy sources into the grid expands, the grid codes for power system connection are progressively becoming more defined, leading to active discussions and evaluations in this area. In this paper, we propose a method for selecting optimal reactive power compensation capacity when multiple offshore wind farms are integrated and connected through a shared interconnection facility to comply with grid codes. Based on the requirements of the grid code, we analyze the reactive power compensation and excessive stability of the 400MW wind power generation site under development in the southwest sea of Jeonbuk. This analysis involves constructing a generation site database using PSS/E (Power System Simulation for Engineering), incorporating turbine layouts and cable data. The study calculates reactive power due to charging current in internal and external network cables and determines the reactive power compensation capacity at the interconnection point. Additionally, static and dynamic stability assessments are conducted by integrating with the power system database.

• Journal of Power Electronics
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• v.9 no.5
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• pp.691-699
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• 2009

This paper presents the analysis of series active power filter for reactive power compensation, load balancing, harmonic elimination, and neutral current eradication in three-phase four-wire power systems. Generally, the three-phase four-wire system is widely employed in distributing electric energy to several office building and manufacturing plants. In such systems, the third harmonic and its 3rd harmonics are termed as triple and zero sequence components that do not cancel each other in the system neutral. Consequently, the triple harmonics add together creating a primary source of excessive neutral current. Regarding this concern, this paper presents a new control algorithm for a series hybrid active system, whereas the control approach it adopts directly influence its compensation characteristics. Hence, the advantage of this control algorithm is the direct extraction of compensation voltage reference without phase transformations and multiplying harmonic current value by gain and the required rating of the series active filter is much smaller than that of a conventional shunt active power filter. In order to show the effectiveness of the proposed control algorithm, experiments have been carried out.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.705-707
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• 2000

In this paper, a static synchronous compensator(STATCOM) is proposed in order to compensate both negative-sequence and reactive power. The STATCOM control unit is designed considering the proposed compensation scheme for the unbalanced loads. As a result, the effectiveness of the STATCOM for compensating both negative-sequence and reactive power is verified by computer simulations.