JP2003223220A - Electromagnetic suspension apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic suspension apparatus capable of developing a damping force with a motor, when it is impossible to control the electromagnetic suspension apparatus due to cable disconnection or the like (when there is no control). <P>SOLUTION: When a disconnection of a power cable 81 is detected, a relay control signal is turned off to close a first and second relays 65, 66, and short- circuit a U-phase coil, V-phase coil and W-phase coil via the first and second relays 65, 66. Consequently, when a suspension unit strokes, the motor 3 arranged in the suspension unit operates as a generator, and the resistance of the magnitude being substantially proportional to a stroke speed, that is the damping force, is developed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator and a damper for suppressing vibration due to electromagnetic force, and more particularly to an automobile,
The present invention relates to an electromagnetic suspension device suitable for use in two-wheeled vehicles, railway vehicles, structures and buildings.

[0002]

2. Description of the Related Art As an example of a conventional electromagnetic suspension device, instead of a damping force generating mechanism such as an orifice of a hydraulic damper, a rotary motion motor and a linear motion for converting the rotary motion of a rotor of the rotary motor into a linear motion- There is an electromagnetic suspension device that uses a rotary motion conversion mechanism or uses a direct drive motor. This electromagnetic suspension device displaces a movable part by energizing it to actively operate the motor as an original motor (actuator), while using the motor as a generator (passively) to generate a damping force. ing.

When the motor is used as a generator,
The resistance force generated in the motor (generator), that is, the damping force, is proportional to the magnitude of the current flowing through the coil. Therefore, in order to make the damping force variable, the magnitude of the current flowing through the coil may be adjusted. . To adjust the current flowing through the coil, it is easy to implement by providing a variable resistor in the circuit or a switch that turns the circuit on and off (ON / OFF) and controlling the on / off time ratio of the switch. it can.

For this reason, it is comparative to configure a so-called semi-active damper in which the damping force of the electromagnetic suspension device is variably controlled according to the stroke speed and the stroke position, or variably controlled in real time so as to suppress the vibration of the controlled object. It is easy. Further, when the semi-active damper is configured as described above (used as a generator), it is not necessary to apply electric energy to the electromagnetic suspension device, and the power consumption can be suppressed to a very low level.

Further, if electric energy is applied to the electromagnetic suspension device to use it as a motor, an arbitrary force can be easily generated. Therefore, the force is applied to increase the damping force or generate an arbitrary control force. It is possible to increase the vibration suppressing effect by operating the suspension as an active suspension, and a method of increasing the vibration suppressing effect in this way is also proposed. A DC motor or a synchronous motor is used as a motor in the electromagnetic suspension device.

[0006]

By the way, in the electromagnetic suspension device, the drive system excluding the sensor portion is generally composed of a power source, a motor drive circuit, and a motor for generating a propulsive force and a damping force. At present, the power supply and the motor are difficult to be integrated and separated from each other, and thus a cable for connecting the power supply and the motor is required between the power supply and the motor. Normally, cables are connected between the power supply unit and the motor drive circuit, and between the motor drive circuit and the motor. But,
If these cables are disconnected or if a disconnection occurs in the motor drive circuit (no control), not only the motor cannot generate propulsive force but also damping force, and the motor will be in a non-damped state. There is a problem. Further, when the ignition key is not turned on (ON) or when the battery is dead (no control), power is not supplied to the motor drive circuit or the motor, and the motor is in the non-damped state as described above. There is a problem that it will end up.

The present invention has been made in view of the above circumstances, and provides an electromagnetic suspension device capable of generating a damping force by a motor when the electromagnetic suspension device cannot be controlled (uncontrolled) due to a cable break or the like. The purpose is to provide.

[0008]

The invention according to claim 1 is
A pair of displacement members are provided to be relatively displaceable, a magnet member is provided on one of the pair of displacement members, and a coil member that constitutes a motor together with the magnet member is provided on the other one of the pair of displacement members. A suspension unit that obtains a propulsive force by an electromagnetic force generated between it and the magnet member by energization and a damping force by an electromotive force generated in the coil member by relative displacement of the coil member and the magnet member; An electromagnetic suspension device including control means for controlling energization is provided with abnormality detection means for detecting abnormality of a signal supplied from the control means to the suspension unit, and a short circuit for making the coil member form a closed loop. It is characterized by that. According to a second aspect of the present invention, in the configuration according to the first aspect, the control means is provided on the vehicle body side, the control means and the suspension unit are connected by a cable, and the short circuit is provided integrally with the suspension unit. It is characterized by that.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic suspension device according to a first embodiment of the present invention will be described with reference to FIGS.

In FIGS. 1 and 2, an electromagnetic suspension device 1 is used in an automobile and has four suspension units interposed between each wheel side member and a vehicle body. Suspension units corresponding to the right front wheel side member, the left front wheel side member, the right rear wheel side member, and the left rear wheel side member are respectively provided to the right front wheel side, the left front wheel side, the right rear wheel side, and the left rear wheel side suspension unit 2FR, 2FL, 2R
It is called R, 2RL. Right front wheel side, left front wheel side, right rear wheel side and left rear wheel side suspension units 2FR, 2FL, 2R
Each of R and 2RL is composed of a star-connected U-phase coil, V-phase coil and W-phase coil (reference numeral omitted) 3
Phase synchronous motors (right front wheel side, left front wheel side, right rear wheel side and left rear wheel side motors 3FR, 3FL, 3RR, 3
It is called RL. ) Is provided. Right front wheel side, left front wheel side, right rear wheel side and left rear wheel side suspension unit 2F
R, 2FL, 2RR, 2RL have the same configuration,
Hereinafter, the suspension unit 2 will be collectively referred to as appropriate. Further, the right front wheel side, the left front wheel side, the right rear wheel side, and the left rear wheel side motors 3FR, 3FL, 3RR, 3RL are similarly collectively referred to as the motor 3 as appropriate.

The right front wheel side, the left front wheel side, the right rear wheel side and the left rear wheel side motors 3FR, 3FL, 3RR, 3RL respectively have drivers (right front wheel side, left front wheel side, right rear wheel side and left rear wheel side, respectively). Wheel side drivers 4FR, 4FL, 4RR, and 4RL are connected to drive the motor 3. The right front wheel side, the left front wheel side, the right rear wheel side, and the left rear wheel side drivers 4FR, 4FL, 4RR, 4RL have the same configuration, and are hereinafter collectively referred to as driver 4 as appropriate. The driver 4 is provided in the suspension tower portion corresponding to each wheel. The driver 4 is connected to a motor power source 5 of DC 36V.

A control device 7 (vibration and attitude control means) as control means is connected to the driver 4 via a serial communication bus 6, and an operation command from the control device 7 to the driver 4 and a command from the driver 4 are provided. All kinds of feedback to the control device 7 are serial communication [eg CAN (Cont
Serial communication conforming to the roller area network specifications)
To be done by. The protocol of serial communication is the "command" from the control device 7 and the driver 4
Is a set of "responses", and "commands" and "responses" are always exchanged at regular intervals (for example, 5 ms) [control cycle of the control device 7].

Further, for example, the "command" from the control device 7 to the driver 4 is not transmitted for a certain time (for example, 20 ms) or the "response" from the driver 4 to the control device 7 is not transmitted for a certain time (for example, 20 ms). In such a case, the control device 7 or the driver 4 determines that the system is abnormal, and performs abnormal processing such as “disconnecting the motor power supply 5” and “error display”. Serial communication bus 6
An ABS (Anti-lock Break System) control device 8 and a VDC (Vehicle Dynamics Control) control device 9 are connected to the. ABS control device 8 and VDC control device 9
Is for ensuring the running stability of the vehicle. The electromagnetic suspension device 1, the ABS control device 8 and the VDC control device 9 can operate in cooperation with each other.

The control device 7 controls the energization of the motor 3, and thus the propulsive force generation control by the motor 3, and the motor 3
The damping force is controlled by the electromotive force generation (use as a generator). The control device 7 includes three vertical acceleration sensors (hereinafter, referred to as first, second, and third vertical acceleration sensors) 10, 11, 1 that detect vertical vibrations of the vehicle body.
2, a wheel speed sensor 13, a steering wheel angle sensor 14, a brake sensor 15, and a DC 12V power source (hereinafter referred to as 12V power source) 16 are connected. An external communication device 17 used for system diagnosis and the like is further connected to the control device 7. The first vertical acceleration sensor 10 is provided on the right front wheel suspension tower portion, the second vertical acceleration sensor 11 is provided on the left front wheel suspension tower portion, and the third vertical acceleration sensor 12 is provided on the rear trunk portion.

As shown in FIG. 2, the suspension unit 2 has an outer cylinder member 20 (one of a pair of displacement members) held on the vehicle body side of the vehicle, and one end side inserted into the outer cylinder member 20 so as to be relatively displaceable. The rod 21 (the other of the pair of displacement members) that is fitted and the other end of which is held on the axle side of the vehicle is provided. A plurality of coils 22 (coil members) are provided inside the outer tubular member 20 over a predetermined length in the axial direction so as to be located between the outer tubular member 20 and the rod 21. A magnet (magnet member) 23 is provided in the axial direction over a predetermined length.

Coil 22 and rod 21 (permanent magnet 23)
A tubular guide member (hereinafter referred to as a first guide member) 24 is provided inside the coil 22 so as to be located between the first guide member 24 and the first guide member 24. A sliding portion (hereinafter referred to as a first sliding portion) 25 is provided. An annular guide member (hereinafter referred to as a second guide member) 26 is attached to the open end of the outer cylinder member 20. Inside the second guide member 26, a sliding portion (hereinafter referred to as a second sliding portion) 2 that slides on the rod 21 to guide the movement thereof.
7 is provided. The rod 21 is slidably supported on the outer tubular member 20 by the first sliding portion 25 and the second sliding portion 27.

The coil 22 has a structure in which U-phase, V-phase and W-phase are alternately arranged in the axial direction. Permanent magnet 23
Has a structure in which N poles and S poles are alternately arranged in the axial direction. When the coil 22 is energized, the coil 22 and the permanent magnet 23
An axial thrust is generated between the outer cylinder member 20 and the rod 2.
1 makes relative displacement (stroke). The thrust direction is determined based on the energization direction of the coil 22. In this embodiment,
The motor 3 is composed of the coil 22, the permanent magnet 23, the outer cylinder member 20 supporting the coil 22, the rod 21 supporting the permanent magnet 23, and the like. Also, the outer cylinder member 2
0 and rod 21, and thus coil 22 and permanent magnet 23
Is relatively displaced, an electromotive force is generated in the coil 22, and the motor 3 acts as a generator. The position sensor 30 (see FIG. 4) is attached to the motor 3 of the suspension unit 2.
Are provided, and the coil 22 and the permanent magnet 23 are provided.
As a result, the relative displacement (stroke) between the outer cylinder member 20 and the rod 21 can be detected.

The control device 7 stores a ROM 31 that stores fixed data such as a control program and constants of the electromagnetic suspension device 1, and a CPU 32 that executes the control program and controls the entire electromagnetic suspension device 1.
And a RAM for temporarily storing the calculation result of the CPU 32, etc.
33 and a timer 34 that generates a sampling time and the like. The control device 7 further includes the first, second and third
An A / D converter 35 for converting analog signals from the vertical acceleration sensors 10, 11, 12 into digital signals, and a sensor i / o interface for processing signals from the wheel speed sensor 13, the steering wheel angle sensor 14 and the brake sensor 15. (Sensor i / o i / f) 36, CAN interface 37 for serial communication with the driver 4 and the like 12,
5V required by the CPU 32 or the like for the V power supply 16 and 3.3
DC / DC power supply unit 38 for converting to a voltage such as V
And an external communication device interface 39 that sends and receives signals to and from the external communication device 17. In the present embodiment, the power consumption limiting means is configured as one sequence in the control program of the control device 7 stored in the ROM 31.

In the electromagnetic suspension device 1, the first, second and third vertical acceleration sensors detect the vertical vibration of the vehicle body among the vehicle states as described above. Further, the roll amount and the pitching amount of the vehicle body are determined based on the detection signal of the position sensor 30 and the stroke of the suspension unit 2 of each wheel. Further, the detection of the vehicle state is not limited to the first, second, and third vertical acceleration sensors 10, 11, 12 and the position sensor 30, but the wheel speed sensor 13, the steering wheel angle sensor 14, the brake sensor 1 are also available.
I also try to do it by 5.

The control device 7, based on the signals from the first, second and third vertical acceleration sensors 10, 11, 12, the position sensor 30, the wheel speed sensor 13, the steering wheel angle sensor 14 and the brake sensor 15, Control of the suspension unit 2 of each wheel so as to suppress vibrations of the vehicle, changes in posture, and unstable vehicle behavior, and to make the vehicle more stable with respect to vehicle speed, driver's steering wheel, accelerator, and brake operation. The amount is determined and the drive signal of the motor 3 is sent to the driver 4.

As shown in FIG. 4, the driver 4 is a ROM (hereinafter referred to as driver ROM) 40 for storing fixed data such as a motor drive control program and constants.
And a CPU (hereinafter, referred to as a driver CPU) 41 that executes the motor drive control program, controls communication with the control device 7 and controls the driver 4, and a calculation result of the driver CPU 41 and the like. RAM to store
(Hereinafter, referred to as driver RAM.) 42, a FLASH memory 43 that stores rewritable parameters and the like that are unique to the vehicle and the driver, and a timer that generates sampling time and the like (hereinafter, referred to as driver timer) 4
4 and.

The driver 4 further includes a PWM signal generator 45 for driving the motor 3 and a motor power source 5 (DC 36).
V) via the DC bus 47, and the motor power source 5
The current from the motor 3 is converted into a three-phase current for use in driving the motor 3, and this current is supplied to the motor 3 via the motor connecting line 48.
And a current detector 51 provided on the motor connection line 48 for detecting the drive current of the motor 3,
And a line filter 53 provided on the output side of the motor connection line 48. In addition, the driver 4 converts the analog signal from the current detector 51 into a digital signal A /
D converter (hereinafter referred to as driver A / D converter) 54
A position sensor interface (position sensor i / f) 55 for converting the signal from the position sensor 30 into a digital signal and inputting it to the driver CPU 41;
The relay control signal from the PU 41 is applied to the first and second relays 6
Relay interface (relay i
/ F) 60.

The first and second relays 65 and 66 are provided with an exciting coil (not shown) capable of inputting a relay control signal, and a normally closed contact portion (open / closed according to a relay control signal inputted to the exciting coil). (Not shown) and is a normally closed relay. Then, when the relay control signal of the exciting coil is on (ON), the contact portion (and thus the first and second relays 65 and 66) are opened (OFF). In this embodiment, the relay control signal is turned on when the power is turned on [the ignition switch is turned on], and the first and second relays 65 and 6 are turned on.
6 is opened (OFF), and this state [the first and second relays 65 and 66 are open (OFF) state] is normally maintained. As will be described later, the relay control signal is turned off (O
FF) and the first and second relays 65 and 66 are closed (ON).
Will be said.

The driver 4 further includes an overvoltage detector 56 for monitoring the voltage of the DC bus 47, an overheat detector 57 for detecting overheating of the FET 49, and a CANi / f (which is a serial communication interface with the controller 7. (Hereinafter referred to as driver CAN interface) 58 and DC / converts the motor power source 5 into a voltage of 5V, 12V, 15V or the like necessary for the operation of other members such as the driver CPU 41
A DC power supply unit (hereinafter referred to as a driver DC / DC power supply unit) 59 is provided.

When the driver 4 receives a control command such as "servo ON" and a control amount for actually driving the motor 3 from the control device 7 via the serial communication bus 6, the sampling time (control cycle of the driver 4). The phase angle (electrical angle) between the U-phase, V-phase, W-phase coil 22 in the motor 3 and the magnetic circuit formed by the permanent magnet 23, the operating speed of the motor 3, and the current detector from the signal of the position sensor 30 for each The current value and the voltage value of the coil 22 are acquired from the signal of 51, and the PWM signal generator 45 is adjusted so that the motor operation is in accordance with the motor drive command from the control device 7. The control cycle of the driver 4 is set sufficiently faster than the control cycle of the control device 7 (for example, 5 ms), and is set to 250 μs, for example.

In this electromagnetic suspension device 1, when the rod 21 and the outer cylinder member 20 are relatively displaced due to the vertical vibration of the vehicle body, an electromotive force is generated in the coil 22. That is, the motor 3 acts as a generator, and a current flows through the coil 22, so that the suspension unit 2 (motor 3) generates a resistance force, that is, a damping force according to the relative speed of the rod 21 and the outer cylinder member 20. It will be. Further, if a current is passed through the coil 22 according to the relative positional relationship (electrical angle) between the rod 21 and the outer cylinder member 20, and thus the vertical vibration state of the vehicle body, the motor 3 acts as an original motor (actuator). As a result, the propulsive force is exerted, and the suspension unit 2 can improve the vibration suppressing effect.

FIG. 5 shows a circuit (short circuit) 80 for short-circuiting the coil 22 when the cable is broken. The short circuit 80 is
One end of the U-phase coil (a terminal portion on the opposite side to the common connection terminal C1 of the U-phase coil, the V-phase coil and the W-phase coil) and V
The first relay 65 interposed between one end of the phase coil (the terminal portion on the side opposite to the common connection terminal C1), one end of the V phase coil and one end of the W phase coil (to the common connection terminal C1). On the other hand, the second relay 66 is provided between the second relay 66 and the second relay 66, and the U-phase coil, the V-phase coil and the W-phase coil are connected to the first and second relays 65, 65, as will be described later. A short circuit is provided via 66. The short circuit 80 is provided in the suspension unit 2.

The driver 4 and the suspension unit 2 (motor 3) mounted on the vehicle body side extend from the power cable 81 connected to the U-phase coil, the V-phase coil and the W-phase coil of the motor 3 and the position sensor 30. The position signal cable 82, the first and second relays 65 and 66 controlling cables (relay controlling cables) 83, and the ground cable 84 are connected. Further, the first, second and third vertical acceleration sensors 10, 11, 12 and the control device 7 are connected via an acceleration signal cable 85. In this embodiment, in the case where the cables [power cable 81, position signal cable 82, relay control cable 83, acceleration signal cable 85] are disconnected or from the battery [12V power source 16, motor power source 5] When a failure occurs (when no power is supplied), such as when power is not being supplied (hereinafter referred to as “power off” as appropriate),
The driver 4 turns off the relay control signal and outputs it to the first and second relays 65 and 66.

As described above, the first and second relays 65 and 6
6 is a normally closed relay, and the driver 4 is normally used.
The relay control signal is turned on and output from the device, and the first and second relays 65 and 66 are in the open (off) state. At this normal time, the first and second relays 6
Since 5, 66 are opened, the U-phase coil, the V-phase coil and the W-phase coil are not short-circuited, the motor 3 is normally controlled, and the propulsive force is generated (acts as the original motor) and A damping force is generated (operation as a generator).

When the relay control signal is not output from the driver 4 (the relay control signal is turned off), the first,
The second relays 65, 66 are closed (ON) [state equivalent to the steady state], and the U-phase coil, the V-phase coil, and the W-phase coil are closed (ON) by the first and second relays 65, 66.
Therefore, it is in a short-circuited state. That is, as described above, the driver 4 turns off the relay control signal and outputs the relay control signal to the first and second relays 65 and 66 when there is no control [when the cables are disconnected or when the power is cut off]. So the first,
The second relays 65 and 66 are closed and the U-phase coil, the V-phase coil and the W-phase coil are short-circuited.

When the U-phase coil, the V-phase coil and the W-phase coil are short-circuited, the suspension unit 2
When stroked, the motor 3 operates as a generator,
A resistance, that is, a damping force, which is approximately proportional to the stroke speed is generated. A method of detecting a disconnection (abnormality detecting means) and a control method therefor will be described below by taking a specific disconnection point as an example. The disconnection of the power cable 81 (the cable between the driver 4 and the motor 3) is detected as follows.

That is, the driver 4 includes a current detector 5
1 is built in, and it is checked by detecting the output current whether or not the current value to the U-phase coil, the V-phase coil and the W-phase coil instructed by the driver CPU 41 is accurately output, and the detection is performed. Value the driver CPU
Feedback to 41. Then, when the power cable 81 is broken, the current value fed back to the driver CPU 41 becomes an abnormal value (the current value is zero or a very small value). Driver CPU
41 uses this to determine whether or not the power cable 81 is broken.

The driver CPU 41 has a power cable 81.
When it is determined that there is a disconnection (a disconnection of the power cable 81 is detected), the relay control signal is turned off to close the first and second relays 65 and 66, and the U is passed through the first and second relays 65 and 66. The phase coil, the V phase coil, and the W phase coil are short-circuited, the motor control is stopped, and the controller 7 is notified of the disconnection detection.

Next, the disconnection of the position signal cable 82 is determined as follows. In the case where the position sensor 30 is a type of sensor that constantly outputs a signal (for example, the signal changes between 1-5V), it can be determined that the wire is disconnected when the signal is not output. Also, for example, in the case of a sensor in which an output signal is not output, such as in the case of a position sensor for 0-5V phase A and B pulses, the output from the vertical acceleration sensor or the like connected to the control device 7 is naturally used. When the output of the position sensor 30 should change but the output does not change to 0V or so, the position signal cable 82 is disconnected or the position sensor 3 is disconnected.
It can be judged as 0 failure. When the disconnection of the position signal cable 82 is detected, the control device 7 notifies the driver 4 of the motor control stop. Then, the driver CPU 41 performs the short circuit of the U-phase coil, the V-phase coil and the W-phase coil, the stop of the motor control and the notification of the disconnection detection to the control device 7 in the same manner as described above.

The disconnection of the relay control cable 83 is detected as follows. Here, the first and second relays 65 and 66
To open (turn off) the relay control cable 83
Excitation current [Relay control signal content (or signal level)
Is turned on] to excite the exciting coils built in the first and second relays 65 and 66. The disconnection of the relay control cable 83 during normal operation is detected by monitoring the exciting current (relay control signal) by the relay i / f 60 in the driver 4. When the disconnection of the relay control cable 83 is detected, no signal is supplied to the first and second relays 65 and 66, so that the relay control cable 83 is automatically closed (returns to the normal state), and the U-phase coil and the V-phase coil. And the W-phase coil is short-circuited. Further, the driver CPU 41 turns off the relay control signal and stops the motor control,
The controller 7 is notified of the disconnection detection. Here, the reason for turning off the relay control signal is that there is no problem if the relay control cable is completely disconnected, but after disconnection, reconnect,
When the disconnection is repeated, the first and second relays 65 and 6
Since 6 repeats opening and closing, it is necessary to turn off the relay control signal in order to prevent this.

The disconnection of the acceleration signal cable 85 is detected as follows. In this embodiment, the acceleration signals from the first, second, and third vertical acceleration sensors 10, 11, 12 are output as signal outputs of 1 to 5 V centered on, for example, 3 V. Vertical acceleration sensor 10,1
When no signal is output from 1, 12 (for example, the first,
The output signals of the second and third vertical acceleration sensors 10, 11 and 12 are set to 0 V) so that it can be determined that the acceleration signal cable 85 is broken. Then, the driver CPU 41 uses the first, second, and third vertical acceleration sensors 1
Disconnection detection of the acceleration signal cable 85 is performed based on the acceleration signals from 0, 11, and 12. Then, when the disconnection is detected, the driver CPU 41 performs the short circuit of the U-phase coil, the V-phase coil and the W-phase coil, the stop of the motor control and the notification of the disconnection detection to the control device 7 in the same manner as described above.

Further, even when the control device 7 or the driver 4 does not operate normally due to a runaway or the like, the driver CP
U41 stops the power supply to the motor 3, closes the first and second relays 65 and 66, and puts the U-phase coil, the V-phase coil, and the W-phase coil in a short-circuited state. To determine whether or not the runaway has occurred, for example, the relay i / f and the PWM signal generator are set to be regularly accessed from the CPU,
By providing the relay i / f and the PWM signal generator with the function of judging the presence / absence of this periodical access and stopping the output if there is no periodical access, the periodical access will not be performed when a runaway occurs. The output from the i / f and the PWM signal generator is stopped, the power supply to the motor 3 is stopped, and the U-phase coil, the V-phase coil, and the W-phase coil are short-circuited. Further, when the power supply cable 86 connecting the motor power supply 5 and the driver 4 is broken and the power supply to the driver 4 is stopped, the relay control signal is turned off,
The first and second relays 65 and 66 are closed, the U-phase coil,
The V-phase coil and the W-phase coil are short-circuited.

During normal operation of the system, the first and second
The relays 65 and 66 are closed (turned on) for some reason.
When an abnormal operation such as is performed, a short circuit loop (closed circuit) is formed in front of the U-phase coil, the V-phase coil and the W-phase coil,
Driver 4 for U-phase coil, V-phase coil and W-phase coil
Current is no longer supplied from. In this case, an excessive current flows through the power cable 81 by the amount of the removed resistance of the coil 22, and an abnormality in the current value feedback (current value excessive) by the current detector 51 is detected. Is the first and second relays 65, 66
Can detect abnormalities.

When the abnormality of the first and second relays 65 and 66 is detected, the driver CPU 41 short-circuits the U-phase coil, the V-phase coil and the W-phase coil in the same manner as described above.
The motor control is stopped and the controller 7 is notified of the disconnection detection.

The above operation will be briefly described with reference to the flowchart of FIG. The driver CPU 41 fetches the control command from the control device 7 (step S11) and determines whether or not there is an abnormal processing request from the control device 7.
(Step S12). When it is determined No in step S12 (abnormal processing is not required), the driver CPU 41 reads the position data from the position sensor 30 for controlling the motor 3 (step S13).

Whether or not the position signal cable 82 is broken is determined by reading the position data in step S13.
(Step S14). In the next step 15, the motor control logic is executed, the positional relationship between the magnet 23 and the coil 22 of the motor 3 is calculated from the position data, and the current of the U-phase coil, the V-phase coil and the W-phase coil is calculated from the current value feedback (before one sampling). By grasping the value and the like, the control amount for the motor 3 is determined from the required torque, the speed of the motor 3, and the like.

Next, the FE is fed through the PWM signal generator 45.
The voltage applied to the U-phase coil, the V-phase coil and the W-phase coil is adjusted by switching T49, and the motor 3 is controlled to generate a predetermined torque and a predetermined speed.
(Step S16). After that, the current detector 51 fetches the current value feedback of the U-phase coil, the V-phase coil and the W-phase coil (step S17), and judges whether or not there is a disconnection.
(Step S18).

When it is determined Yes in step S12 (abnormal processing is required), or in step S14 Yes
If it is determined to be s (disconnection), the power of the motor 3 is cut off, and abnormal processing such as short-circuiting the first and second relays 65 and 66 and transmitting an abnormal processing status to the control device 7 is performed (step S19). )

As described above, the suspension unit 2 exerts a damping force even during so-called non-control, such as power-off, disconnection of various cables, battery exhaustion (power-off), runaway of the control device 7 and driver 4, and ignition switch off. Can occur and the safety is greatly improved.

If the first and second relays 65 and 66 are of a type that can carry a large current, the risk of damage is reduced. By using the first and second relays 65 and 66 that can carry a large current, the suspension unit 2 can generate a stable damping force for a long time even when it is not controlled, and the safety is improved. Is further improved.

Next, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8. The electromagnetic suspension device of the second embodiment, as shown in FIGS.
It has an FET circuit 49A which replaces T49. FET
The circuit 49A includes six FETs (hereinafter, first to sixth FETs).
Say. ) 541-546. First FET 5
The source [S] of 41 is connected to the drain [D] of the second FET 542, and the connecting portion is connected to the U-phase coil. The source [S] of the third FET 543 is the fourth
It is connected to the drain [D] of the FET 544, and the connecting portion is connected to the V-phase coil. Fifth FET 54
The source [S] of 5 is the drain [D] of the sixth FET 546.
, And the connection portion is connected to the W-phase coil.

From the PWM signal generator 45 to the FET circuit 49
Six control lines 90 are extended to A, and three signal lines 90 among them are the first, third, and fifth FETs 541, 54.
3, 545 (hereinafter, appropriately referred to as the upper arm FET) is connected to the gate [G]. Of the six control lines 90, the other three signal lines 90 are second, fourth, and sixth.
A short circuit auxiliary circuit (hereinafter referred to as a short circuit auxiliary first circuit) 8 is provided to each of the gates [G] of the FETs 542, 544 and 546.
It is connected via 0A. In the second embodiment, the short circuit auxiliary first circuit 80A and the second, fourth and sixth FEs are provided.
A short circuit is formed by T542, 544, and 546.

The first FET 541 is a freewheel diode 91 connecting the source [S] and the drain [D].
Is built in, and current is allowed to flow from the source [S] to the drain [D] through the free wheel diode 91. The free wheel diode 91 is connected between the sources and drains of the second to sixth FETs 542 to 546, similarly to the first FET 541.

First, third and fifth FETs 541, 543
The drain [D] of 545 (FET of the upper arm) is connected to the plus (+) terminal of the motor power source 5. In addition, the second, fourth, and sixth FETs 542, 544, 546
The source [S] of (the lower arm FET) is connected to the minus (−) terminal of the motor power source 5.

The short circuit auxiliary first circuit 80A is an npn-type transistor (hereinafter referred to as a first transistor) 7
0 and a pnp type transistor (hereinafter referred to as a second transistor) 71. First transistor 7
The emitter (E) of 0 and the emitter (E) of the second transistor are connected to each other, and the connection portion is the second, fourth,
6th FET 542, 544, 546 (FE of lower arm
Each gate (G) of T) [in FIG. 8, only the second FET 542 is excited. 〕It is connected to the. The base (B) of the first transistor 70 and the base (B) of the second transistor are connected, and this connection is connected to the control line 90 of the PWM signal generator 45. The collector (C) of the first transistor 70 is connected to a 15V FET gate driving power supply 92. The collector (C) of the second transistor 71 is grounded.

Second, fourth and sixth FETs 542, 544,
A diode 67 and a resistor 68 connected in series are connected in parallel to each drain (D) and gate (G) of 546 (FET in the lower arm). 2nd, 4th, 6th floor
A grounded Zener diode 69 is connected to each gate (G) of the ETs 542, 544 and 546 so that a high voltage is not applied to each gate (G). A capacitor 93 is connected in parallel to each Zener diode 69.

In the second embodiment, the U-phase coil, the V-phase coil and the W-phase coil are short-circuited by the short circuit auxiliary first circuit 80A as will be described later, and is used in the first embodiment. The first and second relays 65 and 66 (short circuit 80) that have been used are eliminated. In the second embodiment, for example, the control line 90 for the second FET 542 is
Is disconnected, the first and second transistors 70 and 71
Is that no voltage is applied to its base (B),
Do not work. At this time, the stroke of the suspension unit 2 causes the motor 3 to operate as a generator, a counter electromotive voltage is generated between the U and V phases, and when the U phase voltage is high, the second F
A U-phase counter electromotive voltage is applied to the drain [D] of the ET 542.

Then, a voltage is applied to the gate [G] of the second FET 542 through the diode 67 and the resistor 68, so that the second FET 542 can be made conductive (ON). As a result, a current flows from the drain [D] side of the second FET 542 to the source, and the fourth FE corresponding to the V-phase coil.
A current flows through the V-phase coil and the W-phase coil via the freewheel diode 91 incorporated in the T544 (that is, the U-phase coil, the V-phase coil and the W-phase coil are short-circuited), and the suspension unit 2 is damped. It will generate force.

Although the counter electromotive voltage is applied to the gate [G] of the second FET 542 through the diode 67 even during normal operation, the resistance value of the resistor 68 is changed because the first and second transistors 70 and 71 operate. If you make it bigger, the second FE
It does not affect the switching operation of T542. That is, when the power cable 81 connected to the motor 3 is broken, the suspension unit 2 strokes, so that the motor 3 operates as a generator and the back electromotive force automatically causes the second FET 542 to conduct (turn on). The suspension units 2 generate a damping force by short-circuiting the coils of each phase and passing a current.

In the second embodiment, even if the gate control signal of the second FET 542 of the driver 4 is broken, the back electromotive force of the motor 3 is used to bring the second FET 542 into conduction (turn it ON), thereby breaking the wiring. However, damping force can be generated. Since the counter electromotive voltage of the motor 3 is used, the second FET 542 can be turned on (turned on) not only when the suspension unit 2 is not making a stroke but also when the stroke speed is low and the counter electromotive voltage is low. Can not. Therefore, if the stroke speed is low, the damping force cannot be generated.

Next, a third embodiment of the present invention will be described with reference to FIGS. 9 and 10. As shown in FIGS. 9 and 10, the electromagnetic suspension device of the third embodiment has a second
The FET gate drive power source 92 of the embodiment is eliminated, and the stroke speed of the suspension unit 2 is low,
Even when the back electromotive force is low, the second, fourth, and sixth FETs 542, 544, and 546 (hereinafter, for convenience, the second FET 542 will be described as an example) of the lower arm FET can be turned on (turned on). The damping force can be generated even in a region where the stroke speed is low.

The third embodiment is the FE of the second embodiment.
It has an FET circuit 49B replacing the T circuit 49A.
The FET circuit 49B is a first short circuit auxiliary for the FET circuit 49A.
Instead of the circuit 80A, the short circuit auxiliary second circuit 80B is provided. The short circuit auxiliary second circuit 80B is a short circuit auxiliary first circuit 80.
In place of the first and second transistors 70 and 71 of A, a third,
It has fourth transistors 72 and 73. 3rd and 4th
The emitters of the transistors 72 and 73 are connected, and this connection is connected to the gate of the second FET 542. The bases of the third and fourth transistors 72 and 73 are connected, and the collector of an npn-type fifth transistor 95 whose emitter is grounded is connected to this connection. In the base (B) of the fifth transistor 95,
The control line 90 is connected.

The collector of the third transistor 72 and the second F
The drain of ET542 is connected via a diode 74 and a resistor 75 which are connected in series. The collector and the emitter of the third transistor 72 are connected via a resistor 78. In the connection part of the resistors 78 and 75,
The other end of the capacitor 76 whose one end is grounded is connected. A Zener diode 77 is connected in parallel to the capacitor 76. The collector of the third transistor 72 and the collector of the fifth transistor 95 are connected via a resistor 96.

In the third embodiment, the second FET 54
When the drain voltage of 2 is high, that is, when the voltage is applied to the drain of the second FET 542 by the back electromotive force of the motor 3, or when the first FET 541 on the upper arm side is ON, the capacitor is passed through the diode 74 and the resistor 75. An electric charge is stored in 76. This voltage is the second
The gate of the FET 542 is set to a voltage that can be sufficiently driven and is maintained at a constant voltage by the Zener diode 77.

The voltage stored in the capacitor 76 serves as a power source for driving the gate and serves as the third and fourth transistors 72,
The gate of the second FET 542 is driven by 73. The gate control signal has a negative logic, and when the gate control signal is low level, the gate of the second FET 542 is turned on, and when it is high level, it is turned off. When the gate signal is not generated due to disconnection or the like, the voltage stored in the capacitor 76 is applied to the gate of the second FET 542 via the resistor 78, the second FET 542 is turned on, and the damping force is generated. Then, in this case, even if the stroke speed of the suspension unit 2 is low and the back electromotive force is low, the second, fourth, and sixth FETs 542 of the FETs on the lower arm are also provided.
544 and 546 (hereinafter, for convenience, the second FET 542 will be described as an example) can be conducted (turned on), and the damping force can be generated even in a region where the stroke speed is low.

In the first to third embodiments, the case where the suspension unit 2 has a cylindrical linear motor structure is taken as an example, but instead of this, the suspension unit 2A shown in FIG. 11 may be used. The suspension unit 2A shown in FIG. 11 is fixed to an outer cylinder member 20A, a cylindrical rod 21A having one end inserted into the outer cylinder member 20A and the other end protruding from the outer cylinder member 20A, and one end side of the rod 21A. Ball nut 165 and ball nut 16
5 is screwed to the outer cylinder member 20A via the bearing 166.
And a ball screw 167 that is rotatably supported. The suspension unit 2A further includes a permanent magnet 23A fixed to a shaft 168 coaxial with the ball screw 167 and a coil 22A fixed to the outer cylinder member 20A.
And a core material (not shown) provided in the coil 22A. An annular guide member 69 is attached to the open end of the outer cylinder member 20A, and a sliding portion 1 that slides on the rod 21A and guides the rod 21A inside the guide member 169.
70 is provided.

In this suspension unit 2A, the coil 22A and the permanent magnet 23 are energized by energizing the coil 22A.
An electromagnetic force is generated between the rod 21A and the permanent magnet 23A (shaft 68), and thus the ball screw 167 is rotated.
0A can be relatively displaced in the axial direction to generate a propulsive force and the vibration suppressing effect can be improved. Further, if the rod 21A and the outer cylinder member 20A are relatively displaced in the axial direction due to the vertical vibration of the vehicle body, The directional movement is converted into rotational movement by the ball nut 165 and the ball screw 167, the permanent magnet 23A (shaft 168) rotates, and electromotive force is generated in the coil 22A, which corresponds to the relative speed of the rod 21A and the outer cylinder member 20A. A resistance force, that is, a damping force will be generated.

In the first to third embodiments, the case where the U-phase coil, the V-phase coil and the W-phase coil are short-circuited at the time of non-control has been described as an example.
You may make it consume the electric power produced when the motor 3 operates as a generator.

[0064]

According to the first aspect of the present invention, the short circuit is provided so that the coil member forms a closed loop when the signal supplied to the suspension unit is abnormal, such as a cable disconnection. The damping force can be obtained by the electromotive force generated in the coil member, and the non-damping force state that could occur in the prior art at the time of failure can be avoided. According to the second aspect of the invention, since the short circuit is integrally provided with the suspension unit, the short circuit can be operated even when there is a failure in the control means or the cable.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an electromagnetic suspension device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the suspension unit of FIG.

FIG. 3 is a block diagram schematically showing the control device of FIG.

FIG. 4 is a block diagram schematically showing the driver of FIG.

5 is a diagram showing a short circuit using a relay of the electromagnetic suspension device of FIG.

FIG. 6 is a flowchart showing an operation of the electromagnetic suspension device of FIG.

FIG. 7 is a diagram schematically showing a second embodiment of the present invention.

FIG. 8 is a diagram showing a short circuit auxiliary first circuit of FIG. 7;

FIG. 9 is a diagram schematically showing a third embodiment of the present invention.

FIG. 10 is a diagram showing the short circuit auxiliary second circuit of FIG. 8;

11 is a cross-sectional view showing another suspension unit replacing the suspension unit of FIG.

[Explanation of symbols]

1 Electromagnetic suspension device 2 suspension units 3 motor 22 coil (coil member) 23 Permanent magnet (magnet member) 65 1st relay (short circuit) 66 second relay (short circuit)

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3D001 AA02 DA17 EA02 EA07 EA08                       EA22 EA34 ED06                 3J048 AA06 AB11 AC08 AD01 DA01                       EA16                 5H223 AA10 BB08 CC01 CC08 DD01                       DD03

Claims (2)

[Claims] 1. A pair of displacement members are provided so as to be relatively displaceable, a magnet member is provided on one of the pair of displacement members, and a coil member that constitutes a motor together with the magnet member is provided on the other side. Propulsive force is obtained by an electromagnetic force generated between the coil member and the magnet member by energizing the coil member,
An electromagnetic suspension device comprising: a suspension unit that obtains a damping force by an electromotive force generated in the coil member due to relative displacement of the coil member and the magnet member; and a control unit that controls energization to the suspension unit. An electromagnetic suspension device comprising: an abnormality detection unit that detects an abnormality of a signal supplied to a suspension unit; and a short circuit that causes a coil member to form a closed loop. 2. The control means is provided on the vehicle body side, the control means and the suspension unit are connected by a cable, and the short-circuit circuit is provided integrally with the suspension unit. Electromagnetic suspension device.