JP2010226844A - Hall sensor abnormality detector and motor drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a Hall sensor abnormality detector which can detect abnormality such as disconnection and short-circuit of a Hall sensor even if a pulse signal of the Hall sensor does not change and to provide a motor drive. <P>SOLUTION: The Hall sensor abnormality detector that the motor drive has is provided with a voltage control circuit making a voltage of a signal outputted from the Hall sensor into a voltage between a first voltage and a second voltage lower than the first voltage, a measuring a circuit measuring voltage of the signal outputted from the Hall sensor as a measured voltage, and a determining circuit detecting abnormality of the Hall sensor based on the measured voltage measured by the measuring circuit. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a Hall sensor abnormality detection device and a motor drive device.

  2. Description of the Related Art Conventionally, a technique for driving a motor and detecting an abnormality such as a disconnection or a short circuit of the motor from a change in a pulse signal of a hall sensor (see FIG. 4) is known (for example, see Patent Document 1).

JP-A-8-331886

  However, in the motor drive circuit shown in Patent Document 1, the motor is driven, and abnormality such as disconnection or short circuit of the motor is detected from the change of the pulse signal of the Hall sensor. Therefore, even if a voltage is applied to the motor, it is not possible to immediately determine the abnormality of the motor, but only after the time from when the motor is moved by the voltage applied to the motor and the pulse signal is output from the Hall sensor has elapsed. Cannot judge. As described above, the motor driving circuit disclosed in Patent Document 1 has a problem that it takes time to determine abnormality after applying a voltage to the motor and supplying a current.

  In addition, there is a problem that erroneous detection may occur when the motor load is high and the motor is difficult to move. For example, when the motor does not move, the pulse signal output from the Hall sensor does not change, so that even if there is an abnormality, the abnormality cannot be detected.

  Since it takes time to determine an abnormality after the current is supplied, or because the abnormality is not detected because the motor load is high, the motor or motor is There was a problem that the drive circuit that drives the drive may be destroyed.

  The present invention has been made in view of such circumstances, and its purpose is to detect abnormality of a Hall sensor that can detect abnormality such as disconnection or short of the Hall sensor even if the pulse signal of the Hall sensor does not change. An apparatus and a motor drive device are provided.

  The present invention has been made to solve the above-described problems. According to the first aspect of the present invention, the voltage of the signal output from the Hall sensor is set so that the voltage is higher than the first voltage and the first voltage. Based on a voltage control circuit that makes a voltage between the low second voltage, a measurement circuit that measures a voltage of a signal output from the Hall sensor as a measurement voltage, and a measurement voltage measured by the measurement circuit, And a determination circuit for detecting an abnormality of the Hall sensor.

  According to a second aspect of the present invention, the Hall sensor and the measurement circuit are connected by a signal line through a first resistor, and the voltage control circuit has a voltage higher than that of the first voltage. One reference power supply is connected to the signal line through a second resistor, and a second reference power supply having a voltage lower than the second voltage is connected to the signal line through a third resistor. The Hall sensor abnormality detection device according to claim 1, wherein

  According to a third aspect of the present invention, the voltage control circuit includes a transistor circuit that connects the second reference power source to the signal line via the third resistor. Item 3. The Hall sensor abnormality detection device according to Item 2.

  According to a fourth aspect of the present invention, in the Hall sensor abnormality detection device according to the third aspect, the transistor circuit is driven by a driving power source that drives the Hall sensor.

  The invention according to claim 5 is characterized in that the determination circuit outputs a first error signal when a measurement voltage measured by the measurement circuit is higher than the first voltage. It is a Hall sensor abnormality detection apparatus in any one of Claims 1-4.

  The invention according to claim 6 is characterized in that the determination circuit outputs a second error signal when the measurement voltage measured by the measurement circuit is lower than the second voltage. It is a Hall sensor abnormality detection apparatus in any one of Claims 1-5.

  The invention according to claim 7 has a detection circuit that detects rising or falling of a signal output from the hall sensor, and the determination circuit detects when the detection circuit detects rising or falling. 7. The Hall sensor abnormality detection device according to claim 1, wherein an abnormality of the Hall sensor is detected based on a measurement voltage measured by the measurement circuit.

  According to an eighth aspect of the present invention, there is provided a voltage control circuit for setting a voltage of a signal output from the Hall sensor to a voltage between a first voltage and a second voltage lower than the first voltage. A hall sensor comprising: a measurement circuit that measures a voltage of a signal output from the hall sensor as a measurement voltage; and a determination circuit that detects an abnormality of the hall sensor based on the measurement voltage measured by the measurement circuit. A motor driving device having an abnormality detection device.

  According to the present invention, even when no signal is output from the hall sensor, the determination circuit can detect the abnormality of the hall sensor based on the measurement voltage measured by the measurement circuit. Therefore, even if the signal from the hall sensor does not change, it is possible to detect an abnormality such as a disconnection or a short circuit of the hall sensor.

It is a block diagram which shows the structure of the motor drive device by one Embodiment of this invention. FIG. 2 is a waveform diagram illustrating a waveform of a signal input from a hall sensor to a determination unit in the hall sensor abnormality detection device of the motor drive device of FIG. 1. It is a flowchart which shows the determination operation | movement by the motor drive device Hall sensor abnormality detection apparatus of FIG. It is a wave form diagram which illustrates the waveform of the signal outputted from the hall sensor judged in the prior art.

<Configuration of motor drive device>
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram showing the configuration of a motor drive device according to an embodiment of the present invention. Here, in the motor drive device, the configuration of the Hall sensor abnormality detection device that mainly detects the abnormality of the Hall sensor that detects the rotation of the motor will be described.

  An ECU (engine unit controller) 1 and an actuator (ACTR) 2 are commonly connected to a power supply line 10 and a GND line 11. A power supply voltage VB is applied to the power supply line 10, and the GND line 11 is grounded. The voltage value of power supply voltage VB is, for example, 12V. The ECU 1 and the actuator 2 are connected by a signal line 12.

  The ECU 1 controls the rotation of the motor that the actuator 2 has. The ECU 1 is controlled by a host control device. As will be described later, the actuator 2 has a Hall IC 4 (Hall sensor) described later that detects the rotation of the motor. A signal indicating the rotation of the motor from the Hall IC 4 is output from the actuator 2 to the ECU 1 via the signal line 12, and is output from the ECU 1 to the host controller. In this way, the host controller controls the rotation of the motor included in the actuator 2 via the ECU 1 while detecting the rotation of the motor.

<Configuration of ECU 1>
Next, the configuration of the ECU 1 will be described. The ECU 1 has a control unit 3 such as a microcomputer. The control unit 3 includes a determination unit 31 (determination circuit), a microcomputer A / D port 32 (measurement circuit), and a microcomputer interrupt port 33 (detection circuit).

  The microcomputer A / D port 32 performs analog-to-digital conversion on an input signal (voltage value) that is an analog signal, and outputs the analog signal to the determination unit 31. The microcomputer interrupt port 33 detects the rise or fall of the input signal, and outputs an interrupt signal to the determination unit 31 when the rise or fall is detected.

  Based on the voltage value measured via the microcomputer A / D port 32, the determination unit 31 determines whether the Hall IC 4 is in a normal state or an abnormal state as will be described later. The determination unit 31 measures a voltage value via the microcomputer A / D port 32 when an interrupt signal is input from the microcomputer interrupt port 33, and the Hall IC 4 is in a normal state based on the measured voltage value. Determine whether there is an abnormal condition.

  Note that the determination unit 31 measures a voltage value via the microcomputer A / D port 32 at regular intervals, and determines whether the state is a normal state or an abnormal state based on the measured voltage value. Good. For example, the determination unit 31 has a built-in timer unit, and the voltage value is measured via the microcomputer A / D port 32 at regular intervals based on the output from the built-in timer unit. Based on the measured voltage value, it may be determined whether the state is normal or abnormal. The timer unit may be included in the motor drive device or may be included in the host control device.

  The control unit 3 is, for example, a microcomputer. The microcomputer A / D port 32 and the microcomputer interrupt port 33 are input terminals of the control unit 3 that is a microcomputer, for example. Moreover, the determination part 31 is a calculating part of the control part 3 which is a microcomputer, for example.

  The microcomputer A / D port 32 and the microcomputer interrupt port 33 are connected to the first terminal of the resistor R6, the first terminal of the capacitor C1, the cathode terminal of the diode D2, and the anode terminal of the diode D1. . A second terminal of the resistor R6 is connected to the first terminal of the resistor R5 and the signal line 12.

  The second terminal of the capacitor C1 is grounded. The anode terminal of the diode D2 is grounded. The cathode terminal of the diode D1 is connected to the reference voltage VCC (first reference power supply). A second terminal of the resistor R5 is connected to the reference voltage VCC. Reference voltage VCC is, for example, 5V.

<Configuration of actuator 2>
Next, the configuration of the actuator 2 will be described. The Hall IC 4 is driven by the power supply voltage VB and the ground voltage GND. The output terminal of the Hall IC 4 is connected to the first terminal of the resistor R3. A second terminal of the resistor R3 is connected to the first terminal of the resistor R4 and the signal line 12. That is, the Hall IC 4 is connected to the signal line 12 via the resistor R3.

  The Hall IC 4 is turned on or off according to the rotation of the motor to be detected. The Hall IC 4 outputs an output signal corresponding to ON or an output signal corresponding to OFF from the output terminal in response to being turned ON or OFF. In the present embodiment, the Hall IC 4 outputs the ground voltage GND when it is on, and outputs OPEN when it is off. This OPEN means, for example, high impedance.

  The output signal output from the Hall IC 4 is input to the ECU 1 via the resistor R3 and the signal line 12. Thereby, the ECU 1 can detect the rotation of the motor.

  The second terminal of the resistor R4 is connected to the collector terminal of the transistor TR1. The emitter terminal of the transistor TR1 is grounded (connected to the second reference power supply). The base terminal of the transistor TR1 is connected to the first terminal of the resistor R1 and the first terminal of the resistor R2. The second terminal of the resistor R1 is grounded. A second terminal of the resistor R2 is connected to the power supply voltage VB.

  The resistors R3, R4, and R5 described above function as a circuit (voltage control circuit) that sets the voltage of the signal output from the Hall IC 4 to an intermediate potential between the ground voltage GND and the reference voltage VCC. The transistor TR1, the resistor R1, and the resistor R2 described above function as a circuit that fixes the voltage of the signal line 12 to the reference voltage VCC when the power supply line 10 is disconnected.

<In normal state>
For example, when normal, the transistor TR1 is in a conductive state. Therefore, when the Hall IC 4 is OFF (OPEN), the voltage of the above-described intermediate potential is the first voltage V1 obtained by dividing the ground voltage GND and the reference voltage VCC by the resistors R4 and R5. Become. When the Hall IC 4 is ON, the above-described intermediate potential voltage is the second voltage V2 that is resistance-divided by the resistors R3, R4, and R5.

  Here, the first voltage V1 is specifically calculated in advance by the following equation 1.

  V1 = (VCC−GND) × (R4 / (R4 + R5)) (Formula 1)

  That is, the first voltage V1 is a voltage obtained by dividing the ground voltage GND and the reference voltage VCC by the resistors R4 and R5 when the resistors R4 and R5 are connected in series.

  The second voltage V2 is calculated in advance by the following equation 2.

  V2 = (VCC-GND) × (RM / (RM + R5)) (Formula 2)

  RM in Equation 2 is a value of a combined resistance in which the resistor R3 and the resistor R4 are connected in parallel, and is calculated in advance by the following Equation 3.

  1 / RM = 1 / R3 + 1 / R4 (Formula 3)

  That is, the second voltage V2 is obtained by combining the ground voltage GND and the reference voltage VCC with the combined resistor RM and the resistor R5 when the combined resistor RM in which the resistor R3 and the resistor R4 are connected in parallel and the resistor R5 are connected in series. The voltage is divided by resistance.

  In Equations 1 to 3, R3 is the resistance value of the resistor R3, R4 is the resistance value of the resistor R4, R5 is the resistance value of the resistor R5, VCC is the potential of the reference voltage VCC, and GND Is the ground potential. In addition, here, it is assumed that the resistance value of the resistor R1 or the like is small compared to the resistor R3, the resistor R4, or the resistor R5.

  The voltage of the signal output from the Hall IC 4 in this way is an intermediate potential (first voltage V1 and second voltage V2) between the ground voltage GND and the reference voltage VCC (see FIG. 2). .

  In the normal case as shown in FIG. 2, the voltage measured by the microcomputer A / D port 32 is the first voltage V1, the second voltage V2, or the first voltage V1 and the second voltage V2. The voltage is between. The voltage between the first voltage V1 and the second voltage V2 is measured because of the transition period from the first voltage V1 to the second voltage V2, and from the second voltage V2 to the first voltage V2. Measured during the transition to voltage V1.

<In case of first to fifth abnormal conditions>
Here, in the case of the first abnormal state in which the wiring (eg, the power supply line 10) between the Hall IC 4 and the power supply voltage VB is disconnected, the voltage measured by the microcomputer A / D port 32 becomes the reference voltage VCC. . This is because, for example, the power supply line 10 is disconnected, so that the transistor TR1 is turned off.

  In the case of the second abnormal state in which the wiring (eg, the GND line 11) between the Hall IC 4 and the ground voltage GND is disconnected, the voltage measured by the microcomputer A / D port 32 becomes the reference voltage VCC. This is because the transistor TR1 becomes nonconductive because the GND line 11 is disconnected, for example.

  In the third abnormal state in which the wiring between the output terminal of the Hall IC 4 and the signal line 12 (for example, the signal line 12) is disconnected, the voltage measured by the microcomputer A / D port 32 is the reference voltage VCC. It becomes. This is because, for example, the signal line 12 is disconnected, so that the microcomputer A / D port 32 is connected to the reference voltage VCC via the resistors R6 and R5.

  Further, when the output terminal of the Hall IC 4 is in the fourth abnormal state short-circuited with the power supply voltage VB, the voltage measured by the microcomputer A / D port 32 becomes the reference voltage VCC.

  When the output terminal of the Hall IC 4 is in the fifth abnormal state short-circuited with the ground voltage GND, the voltage measured by the microcomputer A / D port 32 is the ground voltage GND. Here, the resistance value of the resistor R3 is described as being negligible compared to the resistance value of the resistor R4.

  In the first to fourth abnormal states described above, the voltage measured by the microcomputer A / D port 32 is described as the reference voltage VCC. In this abnormal state, the voltage is measured by the microcomputer A / D port 32. The applied voltage is higher than at least the first voltage V1.

  In the fifth abnormal state described above, the voltage measured by the microcomputer A / D port 32 is described as the ground voltage GND. In this abnormal state, the voltage is measured by the microcomputer A / D port 32. The voltage is lower than at least the second voltage V2.

<Principle of abnormality detection>
That is, in the first to fifth abnormal states described above, the voltage measured by the microcomputer A / D port 32 is higher than the intermediate potential, not the intermediate potential between the reference voltage VCC and the ground voltage GND. Voltage or low voltage. The intermediate potential here is a voltage measured by the microcomputer A / D port 32 in the above-described normal case, and is the first voltage V1, the second voltage V2, or the first voltage V1 and the first voltage V1. 2 is a voltage between two voltages V2.

  Therefore, before the motor is driven, when the voltage measured by the microcomputer A / D port 32 of the motor driving device according to the present embodiment is an intermediate potential, it can be determined to be normal. Conversely, when the voltage measured by the microcomputer A / D port 32 is not an intermediate potential, it can be determined that there is an abnormality.

  Further, when the voltage measured by the microcomputer A / D port 32 is the reference voltage VCC (when it is higher than the first voltage), the first abnormal state to the fourth abnormal state described above are selected. It can be determined that it is in any abnormal state. Further, when the voltage measured by the microcomputer A / D port 32 is the ground voltage GND (when it is lower than the second voltage), it can be determined that the above-described fifth abnormal state is present.

<Operation as an example of Hall sensor abnormality detection device>
Next, an operation as an example of the determination unit 31 included in the Hall sensor abnormality detection device will be described with reference to FIG. First, the voltage of the signal line 12 is measured as a measurement voltage via the microcomputer A / D port 32 (step S101).

  Next, it is determined whether or not the measured voltage measured is higher than the first voltage value V1 (step S102). If the determination result in step S102 is higher than the first voltage value V1, the first error signal is output to the host controller (step S103). The first error signal is a signal indicating that any one of the first to fourth abnormal states described above has occurred.

  If the determination result in step S102 is not higher than the first voltage value V1, it is next determined whether or not the measured voltage measured is lower than the second voltage value V2 (step S104). If the determination result in step S104 is lower than the second voltage value V2, the second error signal is output to the host controller (step S105). The second error signal is a signal indicating that the fifth abnormal state described above has occurred.

  If the determination result in step S104 is not lower than the second voltage value V2, it is normal and the process ends.

  The process of FIG. 3 may be executed only once, for example, before the motor is driven. Even when executed only once, the Hall IC 4 is normal by determining whether or not the voltage measured by the microcomputer A / D port 32 is an intermediate potential between the reference voltage VCC and the ground voltage GND. Or whether it is abnormal.

  As described above, in the Hall sensor abnormality detection device according to the present embodiment, the voltage of the signal output from the Hall sensor (Hall IC 4) is lower than the first voltage V1 and the first voltage V1. A voltage control circuit (reference voltage VCC, ground voltage GMD, resistor R3, resistor R4, and resistor R5) to be a voltage between the second voltage V2 and a voltage of a signal output from the hall sensor is measured as a measurement voltage. It has a measurement circuit (microcomputer A / D port 32) and a determination circuit (determination unit 31) for detecting an abnormality of the Hall sensor based on the measurement voltage measured by the measurement circuit.

  Thus, even when no signal is output from the Hall sensor (Hall IC 4), the determination circuit (determination unit 31) can detect abnormality of the Hall sensor based on the measurement voltage measured by the measurement circuit. . Therefore, even if the signal from the hall sensor does not change, an abnormality such as a disconnection or a short circuit of the hall sensor can be detected.

  And according to the present embodiment, it is not necessary to determine the abnormality after applying a voltage to the motor and driving the current before driving the motor. The possibility that the motor or the drive circuit that drives the motor is destroyed can be reduced.

  Further, according to the present embodiment, even if the motor load is high and the motor is difficult to move, and the pulse signal output from the Hall sensor does not change even when a voltage is applied to the motor, the motor An abnormality such as a disconnection or a short circuit of the Hall sensor can be detected before driving. Therefore, the possibility that the motor or the drive circuit that drives the motor is destroyed due to an abnormally large current or an abnormally large voltage can be reduced.

  As described above, according to the present embodiment, it is possible to reduce the possibility that the motor or the drive circuit that drives the motor is destroyed due to an abnormal large current or an abnormal large voltage.

  3 is executed from the beginning, for example, every time an interrupt signal is input from the microcomputer interrupt port 33 or every certain period, for example, during a period in which the motor is driven. You may make it do. Thus, it is possible to determine whether the Hall IC 4 is normal or abnormal even during a period in which the motor is driven.

  Further, the second terminal of the resistor R4 may be grounded so that the actuator 2 does not have the transistor TR1, the resistor R1, and the resistor R2. Even in this case, the above-described intermediate potential can be generated.

  Moreover, you may make it the control part 3 or the determination part 31 have a high-order control apparatus.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design and the like within a scope not departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... ECU, 2 ... Actuator, 3 ... Control part, 4 ... Hall IC, 10 ... Power supply line, 11 ... GND line, 12 ... Signal line, 31 ... Judgment part, 32 ... Microcomputer A / D port, 33 ... Microcomputer interrupt port

Claims (8)

A voltage control circuit for setting a voltage of a signal output from the Hall sensor to a voltage between a first voltage and a second voltage lower than the first voltage;
A measurement circuit for measuring the voltage of the signal output from the Hall sensor as a measurement voltage;
A determination circuit for detecting an abnormality of the Hall sensor based on a measurement voltage measured by the measurement circuit;
A hall sensor abnormality detection device comprising: The Hall sensor and the measurement circuit are connected by a signal line through a first resistor,
The voltage control circuit includes:
A first reference power supply having a voltage higher than the first voltage is connected to the signal line via a second resistor;
A second reference power supply having a voltage lower than the second voltage is connected to the signal line via a third resistor;
The Hall sensor abnormality detection device according to claim 1. The voltage control circuit includes:
A transistor circuit for connecting the second reference power supply to the signal line via the third resistor;
The hall sensor abnormality detection device according to claim 2, wherein The transistor circuit is
Driven by a driving power source that drives the Hall sensor,
The Hall sensor abnormality detection device according to claim 3. The determination circuit is
A first error signal is output when the measurement voltage measured by the measurement circuit is higher than the first voltage;
The Hall sensor abnormality detection device according to any one of claims 1 to 4, wherein The determination circuit is
A second error signal is output when the measurement voltage measured by the measurement circuit is lower than the second voltage;
The Hall sensor abnormality detection device according to any one of claims 1 to 5, wherein A detection circuit for detecting rising or falling of a signal output from the Hall sensor;
Have
The determination circuit is
When the detection circuit detects rising or falling, it detects an abnormality of the Hall sensor based on the measurement voltage measured by the measurement circuit;
The Hall sensor abnormality detection device according to any one of claims 1 to 6, wherein A voltage control circuit for setting a voltage of a signal output from the Hall sensor to a voltage between a first voltage and a second voltage lower than the first voltage;
A measurement circuit for measuring the voltage of the signal output from the Hall sensor as a measurement voltage;
A determination circuit for detecting an abnormality of the Hall sensor based on a measurement voltage measured by the measurement circuit;
Hall sensor abnormality detection device comprising:
A motor drive device comprising:

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