• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.9
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• pp.39-46
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• 2007

This paper presents a programmable single-phase ac power source that provides a sinusoidal output voltage with an adjustable output amplitude and frequency over a wide range as well as an arbitrary waveform. The ac power source under consideration have a linear power amplifier. The desired output values can be programmed with a personal computer. The power source operates at 220[V]/60[Hz] mains and the output voltage is isolated from the input circuit. The system consists mainly of a power converter to generate and amplify the waveform signal, a controller to control the desired output signal and measure the output parameters, and a control program to set the desired output and display the values. The prototype ac power source was constructed and tested with the results demonstrating a good performance.

• Journal of electromagnetic engineering and science
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• v.16 no.4
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• pp.225-228
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• 2016

KRISS-V, a V-band millimeter-wave source module for a primary RF power standard and calibration system developed by the Korea Research Institute of Standards and Science is here presented. The output power of KRISS-V is several times higher than that of commercial amplifier/multiplier chains and is highly stable (the standard deviations of output power are less than 0.01% in the worst case). The spectral purity of KRISS-V is high enough to consider it a single-tone signal generator. We also added programmable attenuation capability to KRISS-V for remote power control. Moreover, the in-house source module is cost-effective and adaptable to various measurement schemes. The structure of the model as well as detailed component information are introduced so that it can be reproduced.

• Journal of Power Electronics
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• v.17 no.1
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• pp.172-180
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• 2017

The repetitive control (RC) strategy is widely used in AC power systems because of its high performance in tracking period signal and suppressing steady-state error. However, the dynamic response of RC is determined by the fundamental period delay $T_0$ existing in the internal model. In the current study, a ($nk{\pm}i$)-order harmonic RC structure is proposed to improve dynamic performance. The proposed structure has less data memory and can improve the tracking speed by n/2 times. $T_0$ proves the effectiveness of the ($nk{\pm}i$)-order RC strategy. The simulation and experiments of ($6k{\pm}1$)-order and ($4k{\pm}1$)-order RC strategy used in the voltage source inverter is conducted in this study to control the harmonic current source, which shows the validity and advantages of the proposed structure.

• Journal of Power Electronics
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• v.16 no.2
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• pp.553-563
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• 2016

This paper presents a digital hardware implementation of a real-time simulator for a multiphase drive using a field-programmable gate array (FPGA) device. The simulator was developed with a modular and hierarchical design using very high-speed integrated circuit hardware description language (VHDL). Hence, this simulator is flexible and portable. A state-space representation model suitable for FPGA implementations was proposed for a dual three-phase induction machine (DTPIM). The simulator also models a two-level 12-pulse insulated-gate bipolar transistor (IGBT)-based voltage-source converter (VSC), a pulse-width modulation scheme, and a measurement system. Real-time simulation outputs (stator currents and rotor speed) were validated under steady-state and transient conditions using as reference an experimental test bench based on a DTPIM with 15 kW-rated power. The accuracy of the proposed digital hardware implementation was evaluated according to the simulation and experimental results. Finally, statistical performance parameters were provided to analyze the efficiency of the proposed DTPIM hardware implementation method.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.274-277
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• 1999

The paper describes a implementation of space vector pulse-width modulation (SVPWM) voltage source inverter using Field Programmable Gate Array(FPGA) for a induction motor control system. The implemented chip is included logic circuits for SVPWM, dead time compensation and speed detection using Quick Logic, QL16X24B. The maximum operating frequency and delay time can be set to 110MHz and 6 nsec. The designed FPGA for SVPWM can be incorporated with a digital signal processing to provide a simple and effective solution for high performance voltage source inverter drives. Simulation and Implementation results are shown to verify the usefulness of FPGA as a Application Specific Integrated Circuit(ASIC) in power electronics applications

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.8
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• pp.1000-1003
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• 2014

There are 70 vertical and 70 horizontal correctors for Pohang Light Source. Until mid of 2000, power supplies for these correctors were based on 1990's technology, so the global orbit feedback system was not possible with poor 12 bit resolution. A new task force team was assembled to develop new power supplies with BESSY type DAC cards. After the project, two vertical correctors in each lattice were connected with new power supplies, and the global orbit feedback was available within the accuracy of 5 microns. However, this replacement was not enough to satisfy the beam stability requirement of 2 microns for PLS. We have launched another power supply design based on all digital technology. This attempt was completed within a year, and 80 units were assembled in house. Currently, the global orbit feedback system is running successfully with new digital power supplies and the compensation of chamber motion due to the thermal load by using digital displacement transducers attached on each BPMs.

• Journal of Power Electronics
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• v.14 no.4
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• pp.733-741
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• 2014

The integration of photovoltaic (PV) energy sources into DC grid has gained considerable attention because of its enhanced conversion efficiency with reduced number of power conversion stages. During the integration process, a local control unit is normally included with every power conversion stage of the PV source to accomplish the process of maximum power point tracking. A centralized monitoring and supervisory control unit is required for monitoring, power management, and protection of the entire system. Therefore, we propose a field-programmable gate array (FPGA) based centralized control unit that integrates all local controllers with the centralized monitoring unit. The main focus of this study is on the process of integrating many local control units into a single central unit. In this paper, we present design and optimization procedures for the hardware implementation of FPGA architecture. Furthermore, we propose a transient analysis and control design methodology with consideration of the nonlinear characteristics of the PV source. Hardware experiment results verify the efficiency of the central control unit and controller design.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.9
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• pp.698-706
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• 2017

The risk of high power electromagnetic(HPEM) pulse exposure to the devices used in digital control system such as PLC(programmable logic controller) and communication cable is increasing. In this paper, two different frequency ranges HPEMs were exposed to those control systems to assess the each vulnerability. The vulnerability of the EUTs exposed from HPEM were analyzed and compared with a variation of distances and source power. As the EUTs were exposed to higher level of HPEM, the voltage and communication waveform of the control system had shown a distorted response. And the unshielded twisted pair(UTP) cable connected to the EUTs showed operation failures with induced voltage. However, the foiled twisted pair(FTP) cable shielded the connected device efficiently from the HPEM exposure. Therefore, the necessity of the protection measures against the vulnerability of HPEM exposure for the digital control system used in power facilities and industrial site were verified.

• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.214-220
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• 2005

In order to improve energy efficiency and solve power disturbances, power components measurement for both the supply and demand side of a power system must be implemented before appropriate action on the power problems can be taken. This paper presents a DSP (Digital Signal Processor)-based multi-channel (voltage 8-channel and current 10-channel) power measurement system that can simultaneously measure and analyze power components for both supply and demand. Voltage 8-channel and current 10-channel measurement is made through voltage and current sensors connected to the developed system, and power components such as reactive power, power factor and harmonics are calculated and measured by the DSP. The measured data are stored in a personal computer (PC) and a commercial program is then used for measurement data analysis and display. After voltage and current measurement accuracy revision using YOKOGAWA 2558, the developed system was tested using a programmable ac power source. The test results showed the accuracy of the developed system to be about 0.3 percent. Also, a simultaneous measurement field test of the developed system was implemented by application to the supply and demand side of the three-phase power system.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.103-108
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• 1999

The paper describes a implementation of space vector pulse-width modulation voltage source inverter and interfacing of DSP using field programmable gate array(FPGA) for a induction motor vector control system. The implemented chip is included logic circuits for SVPWM, dead time compensation and speed detection using Quick Logic, QLl6X24B. The maximum operating frequency and delay time can be set to 110MHz and 6 nsec. The designed Application Specific Integrated Circuit(ASIC) for SVPWM can be incorporated with a digital signal processing to provide a simple and effective solution for high performance induction motor drives with a voltage source inverter. Simulation and implementation results are shown to verify the usefulness of ASIC in a motor drive system and power electronics applications.