• Proceedings of the KIEE Conference
• /
• 1987.11a
• /
• pp.359-361
• /
• 1987

It is known that the reactive component of AC power in the Power system gives no energy to outside and causes enlargement of power apparatus, voltage fluctuation and unstability of power system. The power conversion system and control system which are composed of power semiconductor devices such as Thyrisor, transistor, GTO and so on have been appeared as new sources of Harmonics. So the reduction of harmonics in power semiconductor system is one of impending problems on the point of energy conservation and improvement of power factor. This paper treates the fundamental review of the harmonics reduction by Current type PWM-Inverter. This Inverter-detects not only the fundamental wave but also that of all harmonics created in the power semiconductor system and is scheduled to control by sampled value.

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.249-251
• /
• 1994

This paper introduces an implementation of high performance voltage source inverter system based on 16bit micro-processor and DSP for the application to modem rolling stock traction system. In contrast with other industry oriented inverter system, this system requires precise control action complying with various load condition and high overload capability. An asynchronous PWM generation and 3' pulse mode technology are adopted in order to improve compliant starting torque characteristics at starting phase and soft backward-forward starting motion.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.12 no.4
• /
• pp.310-317
• /
• 2007

In this paper, the system equation for the balanced two-phase induction motor is derived and the characteristics for speed control is also analyzed in the region of constant torque and constant power. The modified vector control theory is applied to two-phase motor drive system. The speed of two-phase motor drive can be controlled precisely by the modified indirect vector control theory. The modified vector control theory is simpler comparing to the conventional vector control because of the simpler axis transformation. The computer simulations and the experimental results presented to confirm the vector control for two-phase inverter fed two phase induction motor system.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1515-1521
• /
• 2007

In this paper, a unified regenerative inverter system for railway with DC line voltage simulator is proposed. In order to determine the operation characteristics of the regenerative inverter, the DC line voltage simulator is proposed. The DC line voltage simulator, which is based on the AC-DC PWM converter, varies the DC voltage according to the fluctuating voltage which is measured in the actual DC line. The suitable operating point of the regenerative inverter can be estimated from the simulation result. The regenerative inverter operates two modes. When the DC line voltage exceed the operating point, already set up, it works as regenerative inverter to return the excessive power of DC line to the grid. When the DC line voltage is under the operating point, it works as active power filter to compensate harmonic currents. In this paper, the control algorithm of the DC line voltage simulator and that of the regenerative inverter is proposed.

• 한국태양에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.371-376
• /
• 2009

The Power Conditioning System is Power Transfer System which make array DC current to the Grid sinusoidal current. These are Low Frequency Transformer Inverter Type, High Frequency Transformer Inverter Type and Transformer-less Type. Low Frequency Transformer Type has a Excellent Isolation property, but doesn't have competitiveness in Size and Cost. Also High Frequency Transformer Type has a good Isolation property but there are many steps in Power transfer Switching. Nowadays, Transformer-less Type inverter change a transformer to DC/DC Converter which is small and cost effective. In this paper shown the DC/DC Converter Transformer-less Type multi-string inverter design and simulation. The Control Algorithm will be introduced and Simulation was accomplished.

• Proceedings of the KIPE Conference
• /
• 2001.07a
• /
• pp.85-89
• /
• 2001

In this paper, a new line-commutated SCR inverter for renewable power generation system is proposed. The proposed inverter system includes a 6-pulse SCR inverter and an auxiliary circuit. By the proper operation of the auxiliary circuit, the pulse number of the inverter system is increased and the output harmonic currents are reduced. Analysis, control and simulation for 24 pulse operation of the proposed scheme is presented and the experimental results will be provided in the final paper.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.6
• /
• pp.750-755
• /
• 2013

In-wheel motor system gets the driving force from direct-driven motor in the wheel of electric vehicle. It is known as good system for vehicles, from an efficiency, packaging, handling and safety. This paper describes motor and inverter technologies, system configuration and control algorithms for in-wheel type electric vehicle. It is necessary to control on an interrelation perspective because this system drives two motors at same time. In system design, IPMSM(Interior Permanent Magnet Synchronous Motor) including a wide operating range and high-speed rpm is used and flux weakening control is performed in constant power range. Under the torque command from the host controller, auto control box, inverter's output torque is calculated with using torque estimation technique and applied to actual vehicle driving system. It is verified that the configuration and the algorithm are suitable for the in-wheel motor system.

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.283-286
• /
• 1994

A speed control system of the induction motor drives by the load commutated current source inverter is studied in this paper. In general, since the rotating equipments such as pumps, fans and blowers do not require necessarily the accurate speed control performance, a voltage control and a speed sensorless vector control systems are mainly used for this application. In this paper, a new control scheme which has better performance than the voltage control system and simpler control structures than the vector control system is presented. This new proposed method controls the angle of the current vector using the relationship between the inverter output voltage and current, as well as uses the simple method to compensate the effect of the output capacitors.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.7
• /
• pp.74-80
• /
• 2006

This paper describes a solar energy conversion strategy is applied to grid-connected single phase inverter by the maximum power point of conversion strategy. The maximum power point of tracking is controlled output power of PV(photovoltaic)modules, based on generated circuit control MOSFET switch of two boost converter for a connected single phase inverter with four IGBT's switch in full bridge. The generation control circuit allows each photovoltaic module to operate independently at peak capacity, simply by detecting of the output power of PV module. Furthermore, the generation control circuit attenuates low-frequency ripple voltage. which is caused by the full-bridge inverter, across the photovoltaic modules. The effectiveness of the proposed inverter system is confirmed experimentally and by means of simulation.

• Journal of the Korean Society for Railway
• /
• v.2 no.1
• /
• pp.56-66
• /
• 1999

This purpose of this paper is to perform the readhesion control algorithm of the urban railway traction. A study on readhesion control algorithm is done for the adhesion system. This system has all characteristics of the voltage source converter by a process ability to regenerate power. The traction motor is controlled by IGBT inverter. The test equipment composes traction motor, torque-meter, clutch, and a tubular type of interia mass.