• Proceedings of the KIEE Conference
• /
• 2005.10c
• /
• pp.279-281
• /
• 2005

In DC traction substation with 12-pulse diode rectifiers, the DC line voltage tends to rise above noload voltage because it can't absorb the regenerative power caused by electric brakes of train. To solve this problem, an IGBT regenerative inverter should be installed and thus recycles the surplus regenerative power by delivering it to the supply grid. In this paper, the DC traction substation equipped with a IGBT regenerative inverter is studied using computer simulation. Matlab/simulink is used to simulate the operation of regenerative inverter which injects the regenerative power into the supply grid and stabilizes the DC line voltage. It is confirmed that the high quality regenerative power is delivered to the supply grid thorough computer simulation.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.13 no.4
• /
• pp.247-256
• /
• 2008

Regenerative energy generated by regenerative braking of DC traction can cause the system malfunction or damage to the rectifier, or malfunction of the power conversion device in power supply system by DC Line voltage rise in feeder line. Regenerative energy storage system using super capacitor is one of the ways to stabilize DC line voltage. In this paper, energy storage system of DC traction system using super-capacitor bank is implemented and using the field measurement data of the station N and the station S on the Line 2, the operation characteristics of line voltage caused by regenerative energy of electric trains are verified. Also, charge/discharge characteristics of super capacitor are verified as well. Thus, we can verify the operation characteristics of super-capacitor bank for regenerative energy storage system installed in DC Traction. And if we can use field measurement data of DC line voltage, we have obtained cost reduction. The stabilization of the system will be improved by measuring the operation characteristics of regenerative energy storage system in certain section operated by DC traction and predicting the capacity and lifetime of super-capacitor.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.1825-1831
• /
• 2011

One of the major trends in traction power electronics is increasing the switching frequencies. The advances in the frequency elevation have made it possible to reduce the total size and weight of the passive components such as capacitors, inductors and transformers in the DC/DC converter and hence to increase the power density. The traction dynamic performance is also improved. This document describes several aspects relating to the design of resonant DC/DC converter operating at high frequency(10KHz) and the converter topologies and the control method of MAGLEV, which result in soft switching, are discussed.

• Proceedings of the KSR Conference
• /
• 2000.11a
• /
• pp.720-726
• /
• 2000

The advance of traction motor control technology and the complexity of the traction power supply system makes the simulation essential in determining the dimension of the traction power supply system. The conventional method, use of the simplified and/or empirical equations, becomes inadequate in optimization of the design. The simulator presented in this paper is a numerical time based simulator running on a PC. The input to the simulator includes the track data, the train characteristic, network data and operating data. Basically the simulator conducts train running simulation and loadflow study repeatedly. The principle algorithms and its output is discussed in the paper.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.13 no.3
• /
• pp.213-220
• /
• 2008

In this paper, the regenerative inverter system with voltage drop compensation mode is proposed. When the main rectifier is broken, the DC traction can not be supplied the power from the utility. Actually, the reserve rectifier is mounted in the substation to prevent this accident. In this paper, the voltage drop compensation mode is added to the regenerative inverter system in order to substitute the reserve rectifier. The proposed regenerative inverter system returns the regenerative energy from the DC line voltage to the utility. In addition, the inverter can be compensate the harmonics caused by the power conversion devices used in the DC traction system. We demonstrated the effectiveness of the proposed control algorithm by using computer simulation.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.836-845
• /
• 2007

In DC 1500V electric traction substations, diode rectifiers are commonly used to supply stable DC power with electric train sets. However, it operates in the first quadrant of the voltage-current plane and thus needs regenerative inverters which transfer the surplus regenerative power caused by regenerative braking of electric train sets into the grid. In order to select the proper capacity and installation position of regenerative inverter, it needs to investigate the consumed and regenerative energy of the electric traction substations in advance. This paper presents an analysis of regenerative energy in two substations operating in Seoul line 2 and Kwangju line 1. DC line voltage and feeder currents are measured for a day to calculate consumed and regenerative power for four feeders. We calculated an amount of regenerative energy consumed in other feeders and estimated the cost reduction in energy consumption due to the reuse of regenerative energy.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.3
• /
• pp.491-496
• /
• 2012

There are several protective relays used to protect DC traction power supply system for DC railway. These relays, however, are made by different manufactures and they have different ways for their operations. Therefore, there are difficulties for cooperation between the devices or the devices and an upper system. In order to increase interoperability and stability of the system composed of devices made by different manufactures, IEC 61850 international standards are applied to design logical nodes for modeling protective elements used in protective relays.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2004.05a
• /
• pp.104-109
• /
• 2004

Recently, when electric traction system used DC 1500[Vdc] runs on decline of rail road track and slows down, dc voltage goes beyond regular voltage. In this case extra power is forcibly wasted by resister because rectifier of substation and electric train including power converter and so on are out of order. Therefore this paper proposes that the extra power is regenerated through regeneration inverter to AC utility in result this system obstruct to go beyond regular voltage and improve the efficiency. In addition, electric traction system products harmonic current and voltage distortion and reactive power because power converter is used so regeneration inverter normally runs such as active power filter(APF) for improving power quality.

• Proceedings of the KIPE Conference
• /
• 2004.07a
• /
• pp.439-442
• /
• 2004

This paper described a dc power system, which can generate the excessive do power form do bus line to ac source in substation for traction system. The proposed regeneration inverter system for dc traction can be used as both an inverter and an active power filter(APF). As a regeneration inverter mode, it can recycle regenerative energy caused by decelerating tractions and as an active power filter mode, it can compensate for harmonic distortion produced by the rectifier substation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.4
• /
• pp.86-97
• /
• 2006

For the design of DC traction power supply system at new Light Rail Transit(LRT) construction, it is very important to determine system configuration, location and power capacity of substation. However, a LRT system consists of a number of subsystems such as train movement, power supply and traction drives, which inevitably contains many complexities and diversities. The objective of this paper is to clarify and systematize the design procedure and its assessment for the electrification system of a LRT line. This paper discusses in detail our approach to system design and its assessment. The whole DC-feeding network configuration, characteristics of a train, and design method of substation arrangements is thoroughly investigated for the design. As a result of the investigations, the design procedure is clarified and systematized and a computer program for the design and evaluation of the system is developed using the most suitable iterative method with nodal equation. To verify the proposed design and its assessment procedure, case studies for the DC traction power supply system of a planed Korean LRT line are performed.