• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.88-90
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• 2020

운송업의 시장 규모가 커짐에 따라 물건들을 분류하는 방식에 관한 연구들이 활발하게 이루어지고 있다. 그중 크로스벨트소터 방법이 많이 쓰이고 있다. 물건이 카트 위에서 이동하다가 원하는 위치에서 출하는 하는 방식이다. 현재 Bus bar와 collector의 접촉을 이용해 출하 시 전력을 공급하는 방법을 사용하고 있다. 이 방법은 유지와 관리에서 비용이 많이 든다는 단점이 있다. 본 논문에서는 Bus bar와 collector를 사용하지 않고, 카트에서 직접 물건 출하 시 필요한 전력을 만드는 방식에 대해 언급한다. 기존 배터리의 사용 대신, 온도와 수명, 전류방전에 이점을 가진 슈퍼캐패시터를 사용한다. 시뮬레이션을 통해 슈퍼캐패시터의 충전과 출력이 높은 상황에서 슈퍼캐패시터가 전력을 보상해주는 동작을 검증한다.

• Journal of Wind Energy
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• v.13 no.1
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• pp.21-29
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• 2022

With the technological advances of offshore wind turbines, the share of power generated by offshore wind farms in power systems is increasing significantly. An export cable transmission system is necessary to connect offshore wind farms to power systems. The voltage rating and reactive power compensation methods of the export transmission system are very critical, as they can influence the power transmission capacity and CAPEX. With this in mind, this paper suggests an acceptable transmission voltage and reactive power compensation method for an export cable system connecting a 400[MW] offshore wind farm to a power system.

• Proceedings of the KIPE Conference
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• 2013.07a
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• pp.244-245
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• 2013

This paper proposes a control algorithm for permanent magnet synchronous generator with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage offshore wind power system under unbalanced grid conditions. The proposed control algorithm particularly compensates for the unbalanced grid voltage at the point of common coupling in a collector bus of offshore wind power system. This control algorithm has been formulated based on the symmetrical components in positive and negative rotating synchronous reference frames under generalized unbalanced operating conditions. Instantaneous active and reactive power are described in terms of symmetrical components of measured grid input voltages and currents. Negative sequential component of ac input current is injected to the point of common coupling in the proposed control strategy. The amplitude of negative sequential component is calculated to minimize the negative sequential component of grid voltage under the limitation of current capability in a voltage source converter. The proposed control algorithm makes it possible to provide a balanced voltage at the point of common coupling resulting in the generated power of high quality from offshore wind power system under unbalanced network conditions.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.1
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• pp.1-10
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• 2015

This paper proposes a control algorithm for permanent magnet synchronous generators with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage off-shore wind power system under unbalanced grid conditions. Specifically, the proposed control algorithm compensates for unbalanced grid voltage at the PCC (Point of Common Coupling) in a collector bus of an off-shore wind power system. This control algorithm has been formulated based on symmetrical components in positive and negative synchronous rotating reference frames under generalized unbalanced operating conditions. Instantaneous active and reactive power is described in terms of symmetrical components of measured grid input voltages and currents. Negative sequential component of AC input current is injected into the PCC in the proposed control strategy. The amplitude of negative sequential component is calculated to minimize the negative sequential component of grid voltage under the limitation of current capability in a voltage source converter. The proposed control algorithm enables the provision of balanced voltage at the PCC resulting in the high quality generated power from off-shore wind power systems under unbalanced network conditions.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.215-216
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• 2014

This paper proposes a control algorithm for permanent magnet synchronous generator with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage offshore wind power system under unbalanced grid conditions. The proposed control algorithm particularly compensates for the unbalanced grid voltage at the point of common coupling in a collector bus of offshore wind power system. This control algorithm has been formulated based on the symmetrical components in positive and negative rotating synchronous reference frames under generalized unbalanced operating conditions. Instantaneous active and reactive power are described in terms of symmetrical components of measured grid input voltages and currents. Negative sequential component of ac input current is injected to the point of common coupling in the proposed control strategy. The amplitude of negative sequential component is calculated to minimize the negative sequential component of grid voltage under the limitation of current capability in a voltage source converter. The proposed control algorithm makes it possible to provide a balanced voltage at the point of common coupling resulting in the generated power of high quality from offshore wind power system under unbalanced network conditions.