• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.4
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• pp.332-341
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• 2014

A cascaded H-bridge multi-level STATCOM(STATic synchronous COMpensator), which is composed of many cell inverters with independent dc-sources, generates inevitably dc-side voltage unbalance among phases when it compensates unbalanced load. It comes from the difference of flowing active power in each phase when this compensator makes negative-sequence current to eliminate the unbalance of source-side current. However, this unbalance can be controlled by injecting zero-sequence current which is decoupled with grid currents, so the compensator can work well during this balancing process. Both a feedback control algorithm, which produces zero-sequence current proportional to dc-side voltage unbalance within each phase, and a feedforward control algorithm, which makes zero-sequence current directly from the compensator's negative-sequence current, were proposed. The dc-side voltage of each phase can be controlled stably by these proposed algorithms in both steady-state and transient, so the compensator can have fast response to satisfy control performance under rapid changing load. These balancing controllers were implemented and verified via simulation and experiment.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.99-102
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• 2001

The brief proposes to reduce the misadjustment of the adaptive filter coefficients that trace the interference signal in the sidelobe. The proposed sidelobe canceller that has the form of Griffiths-Jim sidelobe canceller with an adaptive compensator that reduces the misadjustment. The proposed sidelobe canceller updates the filter coefficients by the error Signet of the adaptive compensator instead of the output signal. This brief shows the Improvement of the performance by comparing the computer simulation of the output signal of the Griffiths-Jim sidelobe canceller to the output signal of the proposed sidelobe canceller.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.299-302
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• 1997

This paper describes a dynamic var compensator to compensate the line reactance for power transmission and distribution system. The compensator consists of a voltage source inverter with dc capacitor, coupling transformers, and control circuit. The operation of compensator was verified by computer simulations with EMPT and experimental works with a scaled hardware model. The advantage of the proposed system is rapid and continuous regulation of the reactive power.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.508-511
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• 2001

This paper deals with the control algorithm of series voltage compensator that is used to maintain the load voltage when the supply voltage deviates from its nominal voltage. The two reference frame-based controllers using the state feedback algorithm are proposed and verified in the simulation and the experiment The simulation and the experiment show the effectiveness of the proposed control algorithm.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.597-600
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• 2004

In this paper, a static var compensator using PWM Cuk AC-AC converter is presented. The PWM Cuk AC-AC converter is modelled by using complex circuit DQ transformation whereby the basic condition to be used as a var compensator is derived and the static characteristic equations such as input current and reactive power is analytically obtained. Finally, the PSIM simulations show the validity of the modelling and analysis.

• 한국정보통신설비학회:학술대회논문집
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• 2003.08a
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• pp.47-48
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• 2003

A polarization mode dispersion(PMD) compensator with a reponse time less than 200ms has been developed. In our PMD compensator, a reset-free $LiNbO_3$ polarization controller was used in order to reduce the response time, and the compensation algorithm was based on maximization of degree of polarizaiton(DOP).

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.680-683
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• 1999

A thyristor controlled shunt compensator, which is installed in the middle of the transmission line is adopted for controlling real power flow in a simple power transmission system. By means on the Fourier series representation of the thyristor switching action and the system parameters, the thyristor current equations are derived, which transmit the required real power of the simple power transmission system and inform the thyristor firing angle, the thyristor conduction angle, the power flows and the harmonic characteristics EMTP simulations at the various operating points show the dynamic characteristics of the thyristor controlled shunt compensator and correspond to the results calculated with the Fourier series representation.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.220-220
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• 2000

In this paper, some non-interaction problems in tandem cold rolling mill are considered, which are required to control effectively a thickness of the cold .oiled strip. First, Interstand non-interactive compensate. (Interstand NIC) is designed for decoupling the interaction between stands. Next, a L2 optimization based pre-compensator is designed for decoupling the interaction between roll gap and strip tension in the stand. Finally, the effectness of the proposed decoupling methods is demonstrated via simulations.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.237-237
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• 2000

In this paper, The modified dead-time compensator for plants with an integrator and long dead time is proposed. The design procedure takes account of the closed-loop performance and robustness. The tuning of the controller can be done using some information about the plant and its uncertainties. The proposed controller is compared to others recently presented in the literature. Some simulation results verify good closed-performance and robustness of the proposed DTC.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.9
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• pp.1456-1467
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• 1990

The time domain adaptive noise canceller (time domain ANC) with the adaptive compensator and its algorithm, so called compensated least mean squares(CLMS) algorithm, had been introduced to improve the performance of ANC[1]. In this paper the time domain ANC with the adaptive compensator is transformed into the frequency domain ANC with the adaptive ocmpensator. An compensated frequency-domain least mean squares(CFLMS) algorithm that can adapt the proposed frequency domain ANC is presented.