• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.350-353
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• 1999

In this paper, a new simple control method for active power filter which can realized the complete compensation of the harmonic currents is proposed. In the proposed scheme, a compensating current reference generator employing lossless resonato implemented by a DSP(Digital Signal Processor) is introduced. Deadbeat control is employed to contro the active power filter. The switching pulse width based SVM(Space Vector Modulation) is adopted so that the current of active power filter is been exactly equal to its reference at the next sampling instant. To compensate the computation delay of digital controller, the prediction of current is achieved by the current observer with deadbeat response.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1228-1230
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• 1998

The deadbeat control has many advantage such as the ouput response without a ripple and the fast settling time. This paper presents a deadbeat control system to damp out the sustained low frequency oscillation. The proposed deadbeat control system consists of th integral controller and the state observer, and it is simulated on the one-machine infinite-bus model of a power system. The efficiency of the proposed control system is verified through the several case studies.

• Journal of Power Electronics
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• v.11 no.4
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• pp.583-590
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• 2011

Three-level NPC inverters have been put into practical use for years especially in high voltage high power grids. This paper researches three-level active power filters (APFs). In this paper a mathematical model in the d-q coordinates is presented for 3-phase 3-wire NPC APFs. The deadbeat control scheme is obtained by using state equations. Canceling the delay of one sampling period and providing the predictive value of the harmonic current is a key problem of the deadbeat control. Based on this deadbeat control, the predictive output current value is obtained by the state observer. The delay of one sampling period is remedied in this digital control system by the state observer. The predictive harmonic command current value is obtained by the repetitive predictor synchronously. The repetitive predictor can achieve a better prediction of the harmonic current with the same sampling frequency, thus improving the overall performance of the system. The experiment results indicate that the steady-state accuracy and the dynamic response are both satisfying when the proposed control scheme is implemented.

• Journal of Power Electronics
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• v.4 no.2
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• pp.102-111
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• 2004

This paper is concerned with a deadbeat current control implementation of shunt-type three-phase active power filter (APF). Although the one-dimensional deadbeat control method can attain time-optimal response of APF compensating current, one sampling period is actually required fur its settling time. This delay is a serious drawback for this control technique. To cancel such a delay and one more delay caused by DSP execution time, the desired APF compensating current has to be predicted two sampling periods ahead. Therefore an adaptive predictor is adopted for the purpose of both predicting the control error of two sampling periods ahead and bringing the robustness to the deadbeat current control system. By adding the adaptive predictor output as an adjustment term to the reference value of half a source voltage period before, settling time is made short in a transient state. On the other hand, in a steady state, THD (total harmonic distortion) of the utility grid side AC source current can be reduced as much as possible, compared to the case that ideal identification of controlled system could be made.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1791-1804
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• 2018

To achieve a fast dynamic response and to solve the multi-objective control problems of the output currents, capacitor voltages and system constraints, this paper proposes a deadbeat and hierarchical predictive control with space-vector modulation (DB-HPC-SVM) for five-level nested neutral point piloted (NNPP) converters. First, deadbeat control (DBC) is adopted to track the reference currents by calculating the deadbeat reference voltage vector (DB-RVV). After that, all of the candidate switching sequences that synthesize the DB-RVV are obtained by using the fast SVM principle. Furthermore, according to the redundancies of the switch combination and switching sequence, a hierarchical model predictive control (MPC) is presented to select the optimal switch combination (OSC) and optimal switching sequence (OSS). The proposed DB-HPC-SVM maintains the advantages of DBC and SVM, such as fast dynamic response, zero steady-state error and fixed switching frequency, and combines the characteristics of MPC, such as multi-objective control and simple inclusion of constraints. Finally, comparative simulation and experimental results of a five-level NNPP converter verify the correctness of the proposed DB-HPC-SVM.

• 전기의세계
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• v.20 no.4
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• pp.17-22
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• 1971

This paper deals with the analytic structure of feedback controller for linear time invariant discrete systems. On the way of developing the deadbeat controller, some necessary conditions for control policy have been derived. In the case of time delay, it was proved that the q periods delay in the control causes q periods delay in the point at which deadbeat response occurs. Theorems and conclusions are illustrated with some simple nontrivial numerical examples and signal state tracking application problems.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.4
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• pp.47-51
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• 2003

Due to the asymptotic property, deadbeat control which is well used in digital control system can not be applied to the continuous time system. But recently by use of the finite Laplace Transform to transfer function and establishment of some settling conditions, CDBC(Continuous time Deadbeat Control) is studied. For CDBC design, transfer function is constituted with delay elements and then order and interpolation conditions are derived. In other way, digital deadbeat controller is implemented and it's output is changed to continuous type by smoothing elements. In this paper multirate sampling is used and so inner controller is sampled faster than output feedback loop. And End order smoothing elements is placed to the output of digital deadbeat controller. By the multirate sampling overall output response is improved. The controller is impleneted as a serial integral compensator in the forward path and a local feedback compensator introduced into the outpute feedback loop. Matlab Simulink is used for simulation.

• 전기의세계
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• v.25 no.5
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• pp.59-62
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• 1976

Applications of the digital computers in the control systems are not new. But when one tries to integrate the control system with a digital computer to form a feedback loop, he has to solve a great deal of problems in both hardware and software aspects. Such problems are investigated in this paper. For the hardware aspect, one has to design interfaces for both ADC and DAC. Since these are absolutely necessary pieces of hardware, one can notavoid from using them. The interface which employ the programmed data transfer method was designed for this research. For the software aspect, one has to build models for the digital compensator and the controlled system. In order to do that it is necessary to utilize the real time clock and to write his own interrupt service routine. As a sample case, a deadbeat compensator was desinged and tested.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.579-582
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• 1999

This paper presents a design method of deadbeat controller for DC motor driving a rotational system with gear. The results of sampling a continuous-data process does not guarantee that no ripples occur between the sampling instants in the continuous-data output, but the proposed deadbeat control system that consists of the integral controller and the full state observer, and zero order hold using in continuous systems, has many advantages of such as an output response without the ripple and reaching the steady state without error after a given sampling period and faster settling time than the optimal control system in the short sampling period. The results of case study through matlab simulation shown that the efficiency of the proposed controller for DC motor driving a rotational system with gear, is verified by comparing with optimal controller etc.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1056-1058
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• 2000

Deadbeat technique has been proposed as a digital controller for an UPS inverter to achieve the fast response to a load variation and to conserve a very low THD under a nonlinear load condition. This scheme contains a fatal drawback, sensitivity against parameter variation and calculation time delay. This paper proposes a second order deadbeat current controller, which fundamentally solves the calculation time delay problem and certainly guarantees the robustness of the parameter's variation. This is shown theoretically and practically through simulation and experiment.