WO2006028319A1

WO2006028319A1 - Levitation control apparatus for magnetic levitation train

Info

Publication number: WO2006028319A1
Application number: PCT/KR2004/003557
Authority: WO
Inventors: Ho Kyung Sung; Dong Sung Kim; Heong Jae Cho; Mun Hwan Yoo; Bong Seop Kim; Chong Min Lee
Original assignee: Korea Institute of Machinery and Materials KIMM
Current assignee: Korea Institute of Machinery and Materials KIMM
Priority date: 2004-09-10
Filing date: 2004-12-31
Publication date: 2006-03-16
Anticipated expiration: 2007-03-10
Also published as: KR100626335B1; KR20060023815A

Abstract

The present invention provides a levitation control apparatus a magnetic levitation train, which includes a main operation unit digitally converting data inputted from the magnetic levitation train, performing pulse width modulation on the converted data, and transferring the modulated data to a state check & display unit to display a state of the magnetic levitation train, a signal conversion unit removing noise of analog signals inputted from a gap sensor and an acceleration sensor connected to the magnetic levitation train, setting up an initial gap by a variable resistor, and clipping the noise-removed signals to the main operation unit, a transformer over-current protection circuit unit cutting off a signal inputted to the main control unit if an over-current inputted to the main control unit occurs, an RF controller unit detecting a current flowing in the main control unit to make the detected current into a packet from of 23-bytes, transferring the packet to the main control unit to be used for a levitation control, and allowing the main control unit not to use a PWM signal if the current is equal to or greater than a predefined over-current, and a state check & display unit connected to the RF controller unit, controlled by the main control unit to check abnormality of RF reception, and displaying a result of the checked test. Accordingly, the occurrence of malfunction due to the hardware simplification is reduced and other peripheral circuits can sufficiently provide their functions as the protection circuit of the magnetic levitation train as well.

Description

Levitation Control Apparatus for Magnetic Levitation Train

TECHNICAL FIELD

The present invention relates to a levitation control apparatus a magnetic levitation train, in which the same system of the magnetic levitation train is employed overall, in which a structure failing to essentially match with that of the real magnetic levitation train is configured to fit the characteristics of the magnetic levitation train, and by which a test can be performed with the same performance of the magnetic levitation train.

BACKGROUND ART

Generally, a rapid transit railway is opened for traffic to develop a public traffic means with the purpose of supporting the national economy base. Accordingly, life patterns have been changed as well as life paradigms. For instance, the National Capital region is expanded.

The rapid transit railway, which employs a wheel system, reduces its contact and the like in aspect of operating the wheel system, prepares various systems including a railway, a train, and the like such as a rotation of the train to fit its speed, and operates its control system to fit its high speed. Yet, limitation is put on the high-speed train using the wheel system and there are various problems caused by the rapid transit service. Moreover, to overcome the problems, various kinds of technical know-how and operational know-how are needed.

A magnetic levitation train, which is expected as one of the next generation solutions, needs to solve its own problems for test such as an excessive expense, wide test area occupancy, and the like. Currently, the magnetic levitation train system is operated by such an advanced country as Japan, U.S.A., Germany, China, and the like for test equipments and limited regions only. And, it is still regarded as reckless to commercialize the magnetic

i levitation train system despite the excessive expense and the risk proportional to a national-wide scale that combines the entire country as a one-day life zone.

In order to secure the performance and reliability, a levitation control and propulsion system configuring the magnetic levitation train system needs to be sufficiently tested to enhance controller hardware and software reliability. However, there are too many risks and danger in testing the real system variously. And, the various tests need vast expenses as well. Hence, it is preferably recommended to perform a test using a reduced or miniaturized system.

DISCLOSURE OF THE INVENTION TECHNICAL PROBLEM

Even though miniature models imitating the configuration and structure have been prepared in Korea, the reduced model having the basic principle of the magnetic levitation train applied thereto has never been prepared. Hence, it is unable to substantially perform a simulation test of the magnetic levitation train. ^l

TECHNICAL SOLUTION

An object of the present invention is to provide a levitation control apparatus a magnetic levitation train, in which a hardware configuration including an electromagnet generating a levitation force of an intake type magnetic levitation system, a gap sensor detecting an interval signal between a rail and a train, a levitation controller, and a levitation power supply device (chopper) is equivalent to that of a real magnetic levitation train but differs in size only, in which a miniaturized linear motor of a three-phase linear form is installed as a propulsion system, and in which a propulsion power supply device (inverter) employs an operational system of the real magnetic levitation train. Another object of the present invention is to provide a levitation control apparatus a magnetic levitation train, in which the magnetic levitation train is miniaturized to be provided with the same performance of a real magnetic levitation train to enable a same result of testing the real magnetic levitation train, in which the magnetic levitation train is capable of being fully functional, in which a hardware structure of the magnetic levitation train failing to match with that of the real magnetic levitation train is configured with a circuit fitting the characteristic of the magnetic levitation train, and by which a protection circuit for system simplification and endurance enhancement is provided.

ADVANTAGEOUS EFFECTS

Accordingly, the present invention acquires high¬ speed operational processing capability of DSP using the controller as hardware of the magnetic levitation train based on DSP. And, various functions are built in the processor to reduce a size of hardware and the occurrence of malfunction due to the hardware simplification. Moreover, other peripheral circuits can sufficiently provide their functions as the protection circuit of the magnetic levitation train as well.

BRIEF DESCRIPTION QF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

In the drawing, FIG. 1 is a block diagram of a levitation control apparatus a magnetic levitation train according to one embodiment of the present invention.

<brief description of principal cord part of figures> levitation controller 100 main operation unit 110 input/output unit 111

RAM 112 pulse width modulation generator 113 analog/digital converter 114

CPU 115 signal conversion unit 120 gap detection unit 121 1^st and 2^nd differential amplifiers 122, 126

1^st and 2^nd amplifiers 123, 127 first and second 3.3V clipping units 124 and 128 acceleration detection unit 125 over-current protection circuit unit 130 electromagnet 131

MOSFET 132 over-current protection unit 133 current detector 134 signal amplifier 135 RF controller unit 140

RF receiver 141

RF controller 142 state check & display unit 150

BEST MODE FOR CARRYING OUT THE INVENTION

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a levitation control apparatus a magnetic levitation train according to the present invention includes a main operation unit digitally converting data inputted from the magnetic levitation train, performing pulse width modulation on the converted data, and transferring the modulated data to a state check & display unit to display a state of the magnetic levitation train, a signal conversion unit removing noise of analog signals inputted from a gap sensor and an acceleration sensor connected to the magnetic levitation train, setting up an initial gap by a variable resistor, and clipping the noise-removed signals to the main operation unit, a transformer over-current protection circuit unit cutting off a signal inputted to the main control unit if an over- current inputted to the main control unit occurs, an RF controller unit detecting a current flowing in the main control unit to make the detected current into a packet form of 23-bytes, transferring the packet to the main control unit to be used for a levitation control, and allowing the main control unit not to use a PWM signal if the current is equal to or greater than a predefined over- current, and a state check & display unit connected to the RF controller unit, controlled by the main control unit to check abnormality of RF reception, and displaying a result of the checked test.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

FIG. 1 is a block diagram of a levitation Control Apparatus a magnetic levitation train according to one embodiment of the present invention. Referring to FIG. 1, a levitation controller 100 includes a main operation unit 110, a signal conversion unit 120, an over-current protection circuit unit 130 of a transformer, an RF controller unit 140 controlling the magnetic levitation train by wireless, and a state check & display unit 150.

The main operation unit 110 includes an input/output unit 111, a RAM 112, a pulse width modulation generator 113, and analog/digital converter 114, and a CPU 115.

The main operation unit 110 digitally converts data inputted from a signal converting unit to a packet signal, performs pulse width modulation on the converted data, and then transfers the modulated data to the state check & display unit 150 to display a state of the magnetic levitation train.

The input/output unit lllcontrols the data mutually inputted/outputted to/from the signal conversion unit 120, the over-current protection circuit unit 130 of the transformer, and the RF controller unit 140 and provides a protocol suitable for transmitting/receiving the inputted/outputted data. The RAM 112 is a flash RAM provided with a capacity of about 32K words x 16-bits and stores the information necessary for a control and the inputted/outputted data therein.

The pulse width modulation generator 113 receives the data and then performs pulse width modulation on the received and digitalized data. In doing so, if the digitalized data exceeds a reference, the pulse width modulation is not allowable.

The analog/digital converter 114 converts an analog signal, which is inputted from the signal conversion unit 120 and the RF controller unit 140, to a digital signal.

The CPU 113 is a 32-bit device based on a DSP CPU core, in which the flash RAM 111 is built. The CPU 115 is provided with a pulse width modulation (PWM) function, a 10-bit A/D converting function, a serial communication input/output function, a watchdog timer module, and the like, thereby simplifying the control circuit.

The levitation controller 100 has a shape of a rack in which a slot for loading the main operation unit 110 therein can be built, thereby facilitating the assembly or disassembly for a test. The main operation unit 110 is provided with an operation speed of 40MIPS, sixteen A/D channels, eight PWM (pulse width modulation) channels, a data memory of 2.5K words, and a programmable memory of 32Kbytes, and is capable of executing levitation control algorithm smoothly and multiply. The signal conversion unit 120 includes a gap detection unit 121 connected to the magnetic levitation train to detect a gap between the magnetic levitation train and the railway and an acceleration detection unit 125 detecting an acceleration of the magnetic levitation train.

The signal conversion unit 120 is an analog signal processing unit processing signals inputted from a gap sensor and an acceleration sensor. A noise of the detected signal is preferentially removed by a differential amplifier, an initial gap is set up by a variable resistor, and clipping is performed within a range of 3.3V requested by the A/D converter 114 of the main operation unit 110.

The gap signal detected via the gap detection unit 121 of the signal conversion unit 120 is amplified by a first differential amplifier 122. The amplified signal is by a first amplifier 123 again with the setup of an initial gap value. The amplified signal is clipped by a first 3.3V clipping unit 124 to clip to the voltage of 3.3V and is then transferred to the main operation unit 110. The acceleration signal detected via the acceleration detection unit 125 of the signal conversion unit 120 is amplified by a second differential amplifier 126. The amplified signal is amplified by a second amplifier 127 again with the setup of the acceleration value according to 1.5V/g. And, the amplified signal is clipped by a second 3.3V clipping unit 128 to clip to the voltage of 3.3V and is then transferred to the main operation unit 110.

The over-current protection circuit unit 130 of the transformer is a chopper control unit. Once over-current occurs, the over-current protection circuit unit 130 turns off a MOSFET transistor as a signal is cut off by a NAND gate. In doing so, PC922 is used for the electrical insulation between a power unit and a control unit.

Specifically, in the over-current protection unit 130 of the transformer, a current detector 134 preferentially detects a supply current that is supplied to an electromagnet 131.

The current detector 134 transfers the corresponding information to an over-current protection unit 133. The signal detected by the current detector 134 is amplified by a signal amplifier 135 to be transferred to the main operation unit 110. The over-current protection unit 133 recognizes the gap and acceleration signals received from the main operation unit 110 and a current value of the electromagnet inputted via the signal amplifier 135, and adjusts the current value of the electromagnet 131. This means to change the current value of the electromagnet 131 according to the gap value and the acceleration value. Thus, the current value is repeatedly fed back to be inputted so that the current value is varied, whereby a constant speed and a constant gap can be sustained.

Meanwhile, in the RF controller unit 140, the current flowing in the main control unit 110 is detected as a voltage form by a current detection analog photo-coupler. The current detection analog photo-coupler is a device capable of measuring a maximum peak current of 35 [A] and a regulated current of 25 [A] according to arrangement of an input terminal. In this case, by considering the current supplied to the electromagnet 131, the circuit is configured to measure a maximum current of the device. And, the measured current is A/D-converted to be transferred to the main control unit 110 to be used for a levitation control. Moreover, if the measured current exceeds an over- current set up by a comparator, a PWM signal cannot be used. The RF controller unit 140 makes the data of the gap sensor and the acceleration sensor and the data of a current state of the miniaturized magnetic levitation train into 23-byte packets and then transfers the packets to a monitoring PC.

The RF controller unit 140 includes an RF receiver 141 and an RF controller 142. The RF receiver 141 receives data from a magnetic levitation train system. The data received from the magnetic levitation train may be gap information, acceleration information, or other magnetic levitation train information required for operating the magnetic levitation train. The data are controlled by the main control unit 110 so as to be smoothly received from the signal conversion unit 120 by wireless.

The RF controller 142 includes an analog/digital converter, a CPU, an input/output unit, and a communication control unit. And, the state check & display unit 150, which is connected to the RF controller unit 140, is controlled by the main control unit 110 to check abnormality of RF reception. Moreover, the state check & display unit 150 displays the test results to enable a tester or operator to recognize the operational state of the magnetic levitation train.

INDUSTRIAL APPLICABILITY

The present invention relates to a levitation control apparatus a magnetic levitation train, in which the same system of the magnetic levitation train is employed overall, in which a structure failing to essentially match with that of the real magnetic levitation train is configured to fit the characteristics of the magnetic levitation train, and by which a test can be performed with the same performance of the magnetic levitation train, thereby the occurrence of malfunction due to the hardware simplification is reduced and by testing protection circuit of the magnetic levitation train it can be apply to the real magnetic levitation train.

Claims

WHAT IS CLAIMED IS:

1. A levitation control apparatus a magnetic levitation train, comprising: a main operation unit 110 digitally converting data inputted from the magnetic levitation train, performing pulse width modulation on the converted data, and transferring the modulated data to a state check & display unit 150 to display a state of the magnetic levitation train; a signal conversion unit 120 removing noise of analog signals inputted from a gap sensor and an acceleration sensor connected to the magnetic levitation train, setting up an initial gap by a variable resistor, and clipping the noise-removed signals to the main operation unit 110; a transformer over-current protection circuit unit 130 cutting off a signal inputted to the main control unit 110 if an over-current inputted to the main control unit occurs; an RF controller unit 140 detecting a current flowing in the main control unit 110 to make the detected current into a packet form of 23-bytes, transferring the packet to the main control unit 110 to be used for a levitation control, and allowing the main control unit 110 not to use a PWM signal if the current is equal to or greater than a predefined over-current; and a state check & display unit 150 connected to the RF controller unit 140, controlled by the main control unit 110 to check abnormality of RF reception, and displaying a result of the checked test.

2. The apparatus of claim 1, the signal conversion unit 120 comprising: a gap detection unit 121 detecting a gap between the magnetic levitation train and a railway; an acceleration detection unit 125 detecting an acceleration of the magnetic levitation train; differential amplifiers 122 and 126 amplifying gap and acceleration signals detected via the gap and acceleration detection units 121 and 125, respectively; amplifiers 123 and 127 setting the amplified signals to an initial gap value and an acceleration value according to 1.5V/g to amplify, respectively; and first and second 3.3V clipping units 124 and 128 clipping the signals amplified by the amplifiers 123 and 127 by a voltage value of 3.3V, respectively.

3. The apparatus of claim 1, the over-current protection circuit unit 130 comprising: a current detector 134 detecting a current of an electromagnet 131 providing a magnetic force to the magnetic levitation train; an over-current protection unit 133 recognizing gap and acceleration signals received from the main operation unit 110 and a current value of an electromagnet inputted via a signal amplifier 135 amplifying the detected current to transfer to the main operation unit 110; and a MOSFET 132 adjusting the current value of the electromagnet 131 under a control of the over-current protection unit 133.

4. The apparatus of claim 1, the RF controller unit 140 comprising: an RF receiver 141 receiving data from a magnetic levitation train system; and an RF controller 142 receiving a command inputted from the main controller 110 and performing packet processing on data received from the RF receiver 141.