• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.627-630
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• 1991

This study is about vector controlled inverter for high quality elevator drive that is to improve the settling accuracy of elevator car and passenger's comfort in commercial buildings. In this study, an instantaneous space vector control type inverter was used to reduce the torque ripple ant to improve the velocity follow-up. This method calculates Instantaneous actual output torque and flux of induction motor by voltage and current, then compares them with a reference values by a speed regulator. The outputs of comparators select a switching mode, for an optimal voltage vector. Also, this study used IGBT (Insulated Gate Bipolar-Transistor), a high speed switching element, to reduce sound noise level, and DSP (Digital Signal Processor) was used to improve the reliability of the control circuit by fully digitalization.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.2
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• pp.116-121
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• 2009

Distributed power systems (DPSs) has been widely used various industrial/military applications due to their various advantages. Furthermore, the "All electric" concept, in conjunction with DC DPS, appears to be more advanced and mature in the AEV(All-Electric Vehicular) industry. Generally, AEV carry many loads with varied functions. However, there may be large pulsed loads with short duty ratios which can affect the normal operation of other loads. In this paper, a converter with spilt capacitors and a simple adaptive controller is proposed as a active damping device to mitigate the voltage transients on the bus. The proposed converter allows the smaller capacitive storage. In addition, the proposed control approach has the advantage of requiring only one sensor and performing both the functions of mitigating the voltage bus transients and maintaining the level of energy stored. The control algorithm has been implemented on a TMS320F2812 Digital Signal Processor (DSP). Simulation and experimental results are presented which verify the proposed control principle and demonstrate the practicality of the circuit topology.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1009-1012
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• 1995

This paper presents an example of the development of motor drives for machine tools. Machine tools need motor drives with high control precision and performance. We developed a motor drive system that meets these requirements. The converter, the one component of drive system, adopts modular structure and high DC-link voltage. The drive which consists rest part of drive system is developed based on TMS320C32 DSP and state-of-the-art circuit technology. In this paper each developed parts are described in terms of its structure, specification and features.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.121-124
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• 2004

In this paper, Simple and inexpensive analog maximum power point tracker (MPPT) algorithm for photovoltaic power system and low power system of doesn't use digital signal processor (DSP). The control circuit is composed such that the actual current and voltage are sensed directly from the PV array. These two signals are then multiplied by a single-chip multiplier. The multiplier output go through different time constants genesis pulse width modulated to switch. Finally those were verified through simulation.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.1
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• pp.96-102
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• 1995

This paper presents the VHSIC Hardware Description Language(VHDL) implementation of the Fixed Point Covariance Lattice(FLAT) algorithm for an Linear Predictive Coding(LPC) analysis and its related algorithms, such as the forth order high pass Infinite Impulse Response(IIR) filter, covariance matrix calculation, and Spectral Smoothing Technique(SST) in the Vector Sum Exited Linear Predictive(VSELP) speech coder that has been Selected as the standard speech coder for the North America and Japanese digital cellular. Existing Digital Signal Processor(DSP) chips used in digital cellular phones are derived from general purpose DSP chips, and thus, these DSP chips may not be optimal and effective architectures are to be designed for the above mentioned algorithms. Then we implemented the VHDL code based on the C code, Finally, we verified that VHDL results are the same as C code results for real speech data. The implemented VHDL code can be used for performing logic synthesis and for designing an LPC Application Specific Integrated Circuit(ASOC) chip and DsP chips. We first developed the C language code to investigate the correctness of algorithms and to compare C code results with VHDL code results block by block.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.351-357
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• 2007

SRM (Switched Reluctance Motor) has not been put into practical use since it has been developed in mid 19th centuries, but the switching element using semi-conductor was developed in 1950's which made possible to produce small size staffing motors. The research activities have been lively conducted regarding SRM since 1960's, nowadays, more research activities are being carried out focusing on developing small home appliances such as vacuum cleaners and washing machines. This thesis explains the study of controller design applied to SRM concept. This controller executes controller algorithms via $\mu$ - processor to increase stability and precise measurement, and VHDL (Very high speed integrated circuit Hardware Description Language) is designed to generate SRM driving signal.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.362-368
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• 2007

A single-phase uninterruptible power supply system equipped with a superconducting magnet energy storage unit is proposed to achieve a simple circuit configuration and higher system reliability. It reduces a number of switching devices by applying a common-arm scheme. Removing some switches or substituting passive elements for active switches can increase the sophistication and reduces degree of freedom in control strategy. However, high-performance DSP controller can execute the complicated control task with no additional cost. Operational principles to normal, stored-energy, and bypass mode are discussed in detail. The validity of the proposed system is verified by experimental results.

• Journal of Power Electronics
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• v.13 no.5
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• pp.787-797
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• 2013

Despite the advantages offered by multilevel inverters, one of the main drawbacks that prevents their widespread use is their circuit complexity as the number of power switches employed is usually high. This paper presents a new multilevel inverter topology with a considerable reduction in the number of power switches used through the switch-sharing approach. The fact that the proposed inverter applies two bidirectional power switches for sharing among the three phases does not prevent it from producing seven levels in the line-to-line output voltage waveforms. A modified scheme of space vector modulation via the application of virtual voltage vectors is developed to generate the PWM signals of the power switches. The performance of the proposed inverter is investigated through MATLAB/SIMULINK simulations and is practically tested using a laboratory prototype with a DSP-based modulator. The results demonstrate the satisfactory performance of the inverter and verify the effectiveness of the modulation method.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.149-153
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• 2003

This paper presents a current-source-inverter based on a buck-boost configuration and its application for residential photovoltaic system. The proposed circuit has five switches. Among them, only one switch acts as chopping, and the other determine the polarity of output; therefore, it can reduce the switching loss. Because the input inductor current is operated on the discontinuous conduction mode, high power factor can be achieved without additional input current controller. So the overall system shows a simple structure. The operational modes are analysed in depth, and then it was verified through the experimental results using a 150 [W] prototype equipped with digital signal processor TMS320F241.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.154-157
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• 2003

This paper presents a current-source-inverter based on a buck-boost configuration and its application for residential photovoltaic system. The proposed circuit has five switches. Among them, only one switch acts as chopping, and the other determine the polarity of output; therefore, it can reduce the switching loss. Because the input inductor current is operated on the discontinuous conduction mode, high power factor can be achieved without additional input current controller, So the overall system shows a simple structure. The operational modes are analysed in depth, and then it was verified through the experimental results using a 150 [W] prototype equipped with digital signal processor TMS320F241.