• Title, Summary, Keyword: electric retarder

Search Result 12, Processing Time 0.087 seconds

A Study on Electromagnetic Retarder's Power Recovery System and Regenerating Voltage Control (전자기형 리타더의 전력회수장치 및 회생전압제어에 대한 연구)

  • Jung, Sung-Chul;Ko, Jong-Sun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.66 no.8
    • /
    • pp.1207-1214
    • /
    • 2017
  • In the case of frequent braking, when driving downhill or long distance, conventional brakes using friction are problematic in braking safety due to brake rupture and fading phenomenon. Therefore auxiliary brakes is essential for heavy vehicles. And several research has been actively conducted to improve energy efficiency by regenerating mechanical energy into electric energy when the vehicles brake. In this paper, a voltage control method is utilized to recover the electric energy generated in the electromagnetic retarder instead of the eddy current. To regenerate the braking energy into the electrical energy, a resonant L-C circuit is configured in the retarder. The retarder can be modeled as self-excited induction generator due to its operating principle. The driving conditions according to the retarder's parameters are made into 3-D maps. Also, the voltage of the resonant circuit changing depending on the driving pulse applied to the FET was analyzed. For the control of this voltage, we proposed an algorithm using the PI controller. The controlled voltage is converted by a 3-phase AC/DC converter and then charged to a battery inside the heavy vehicles through a DC/DC converter. Electromagnetic retarder and its controller are validated using Matlab Simulink. We also demonstrate the voltage controller through the actual M-G set experiment.

Electromagnetic Retarder's Power Recovery Device and Voltage Control (전자기형 리타더의 전력회수장치 및 전압제어)

  • Jung, Sung-Chul;Yoon, In-Sik;Ko, Jong-Sun
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.21 no.5
    • /
    • pp.396-403
    • /
    • 2016
  • Usually, large-sized buses and trucks have a very high load. In addition, frequent braking during downhill or long-distance driving, causes the conventional method using the brake friction to have a problem in safety because of brake fade and brake burst phenomenon. Auxiliary brakes dividing the braking load is essential. Hence, environment-friendly auxiliary brakes, such as contactless brake rather than the engine auxiliary brake system are needed. A study aimed at improving the energy efficiency by recharging electric energy with changing mechanical to electrical energy that occurs when braking is actively in progress. In this paper, the voltage control method is utilized to recover the electric energy generated in the electromagnetic retarder instead of the eddy current. To regenerate the braking energy into the electrical energy, the resonant L-C circuit is configured in the retarder. The voltage generated in the retarder is simply modeled as a transformer. However, retarder voltage control in this paper is simulated by modeling the induction generator because this induction generator modeling is more practical than transformer modeling. The changes in the voltage of the resonance circuit, which depends on the switch pulse duration of the control device, were analyzed. A PI controller algorithm to control this voltage is proposed. The feasibility of modeling retarder and voltage controller are shown by using MATLAB Simulink in this paper.

The liquid crystal alignment effect of in-cell retarder using homogeneous alignment layer (수평 배향막을 이용한 내장형 위상지연 박막의 액정 배향 효과)

  • Choi, Min-Oh;Lim, Young-Jin;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.449-450
    • /
    • 2005
  • Alignment characteristic of liquid crystal (LC) on in-cell retarder which is composed of reactive mesogens has been tested. The in-cell retarder which is polymerized on top of the homogeneous alignment layer (AL) has an optic axis along the rubbing direction of the homeogenous AL and does show good alignment effect of the LC without showing any defects, which possibly allows a skip of another AL on the in-cell retarder that was required conventionally to control alignment of the LC. However, the measured pretilt angle is only 0.04 degree so that disclination lines are generated for a cell that uses the in-cell retarder as an AL when the LC is tilted upward by a vertical electric field.

  • PDF

Study on Scoring of Hypoid Gear Set in Bus with Retarder (리타더 장착 버스 하이포이드 기어의 스코링에 관한 연구)

  • Yang, J.H.;Kim, Y.J.
    • Journal of the Korea Society For Power System Engineering
    • /
    • v.13 no.6
    • /
    • pp.102-109
    • /
    • 2009
  • A retarder, as a supplementary brake system that is not friction-based, is frequently used in heavy-duty vehicles generally to slow the vehicles down on inclines. The electric retarder mainly used in a heavy-duty bus is generally placed between the transmission and the axle. The rotor inside the retarder system is attached to the axle. The operation of the retarder within a driven vehicle generates reverse torque due to coast driving force on hypoid gears in the differential gear system. By the reverse torque, scoring or scuffing on the hypoid gear teeth may directly occur. The scoring may be generated due to excessive contact stresses on the tooth surface. In this study, tooth contact stresses and contact patterns were analysed in order to investigate on the tooth scoring phenomenon using a finite element analysis program T900 in which the Hertzian contact stress formula was taken. Backlash, wear and surface finish were considered in the finite element simulation on the scoring.

  • PDF

DC-DC Converter Design For Electric Regenerative auxiliary Brake System (전기식 회생 보조 브레이크 시스템을 위한 DC-DC 컨버터 설계)

  • Kwak, Tae-Kyun;Moon, Chae-Joo;Lee, Jun-Young;Ko, Jong-Sun;Yoo, Chang-Hee
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.14 no.3
    • /
    • pp.519-528
    • /
    • 2019
  • Current brake system changes the kinetic energy into heat energy by friction-type of brake that the braking action is diverging into the air. The system has a device called a retarder that generates braking force. High-tech research on the high-speed response characteristics of retarders utilizing part of the braking energy of the retarder to save electrical energy consumption is already underway in advanced countries. In this paper, we propose DC-DC converter which converts 3-phase voltage generated from retarder to 24V DC voltage for battery charging and verify its validity through experiments.

The Development of a Motor and Controller for Hybrid System (하이브리드 시스템용 모터 및 제어기 개발)

  • Ha, Hoi-Doo;Park, Jung-Woo;Kim, Jong-Moo
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.231-233
    • /
    • 1995
  • The new hybrid scheme for electric bus is presented in this paper. This system is composed of a three-phase AC induction motor, one inveter and one system controller. The motor can be acted as starter, motor itself, alternator, generator and retarder. Various functions are simulated. The design stage has been finished. And the various experimental tests are undertaken now.

  • PDF

Design and Analysis of the Eddy Current Brake with the Winding Change

  • Cho, Sooyoung;Liu, Huai-Cong;Lee, Ju;Lee, Chang-Moo;Go, Sung-Chul;Ham, Sang-Hwan;Woo, Jong-Hyuk;Lee, Hyung-Woo
    • Journal of Magnetics
    • /
    • v.22 no.1
    • /
    • pp.23-28
    • /
    • 2017
  • This paper is a study of the eddy current brake designed to replace the air brake of railway application. The eddy current brake has the advantage of being able to take a high current density compared to the other application because this brake is used for applying brakes to the rolling stock for a shorter amount of time. Also, this braking system has the merit of being able to take a high current density at low speed rather than at high speed, because the heat generated by the low speed operation is less than that of the high speed operation. This paper also presents a method of improving the output torque of the eddy current brake at low speed operation through a change of the winding as well as the basic design.

Wide Viewing Angle Transflective Liquid Crystal Display using Fringe-Field Switching Mode (FFS 모드를 이용한 광시야각 반투과형 액정 디스플레이)

  • Song, Je-Hoon;Lim, Young-Jin;Park, Chi-Hyuk;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.567-570
    • /
    • 2004
  • We have designed a single gap transflective liquid crystal display (LCD) driven by a fringe electric field, in which the LCs are homogeneously aligned in the initial state. In the reflective and transmissive areas, the degrees of the rotation of the LC director are $22.5^{\circ}$ and $45^{\circ}$, respectively. Utilizing this mechanism and an in-cell retarder with a quarter-wave plate that is used below the LC layer, the transflective LCD using fringe-field switching (FFS) mode is realized.

  • PDF

Analysis and Performance of the Self Excited Eddy Current Brake

  • Cho, Sooyoung;Jeong, Teachul;Bae, Jaenam;Yoo, Changhee;Lee, Ju
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.1
    • /
    • pp.459-465
    • /
    • 2017
  • This paper describes a performance analysis of self-excited eddy current brake(SECB). Stator winding of SECB is connected by capacitor instead of voltage source, and SECB's braking force is generated by L-C resonance. SECB has wide range of driving and nonlinear inductance as well. Therefore, it is important to select capacitance based on the value of inductance. This paper discusses about the process of deciding capacitance and the change of resonance frequency based on the inductance change in each speed. Also the braking force was confirmed by the experimental model of SECB.