KR20180029494A - Motor Controlling Apparatus And The Method Thereof - Google Patents

Abstract

The present invention relates to a motor control apparatus and method for detecting the failure of a plurality of amplifiers at the same time so as to cope with the occurrence of the failure. A motor control apparatus according to an embodiment of the present invention includes a current sensor for detecting a current which a motor driving part supplies to a motor, a battery for supplying power to the motor driving part, a voltage detection part for detecting a voltage outputted from the current sensor; a reference data generation part for converting the output voltage of the battery into first reference data, converting the positive output voltage of the motor to second reference data, and converting the negative output voltage of the motor to third reference data, and a control part for determining the generation of a counter electromotive force of the motor based on the first to third reference data and controlling the driving of the motor based on a determination result of the counter electromotive force of the motor.

Description

TECHNICAL FIELD [0001] The present invention relates to a motor control apparatus,

The present invention relates to a motor control apparatus and method. More particularly, the present invention relates to a motor control apparatus and method for detecting a failure of a plurality of amplifiers at the same time (common mode failure detection) so as to cope with the occurrence of a failure.

The electric steering system, which is generally used as a steering device of a vehicle, comprehensively judges the driver's intention and driving situation by using torque, vehicle speed, steering angle, etc., generates steering assist force and transmits it to a steering column, Let it run.

Such an electric steering apparatus includes an ECU (Electronic Control Unit), which analyzes electric signals transmitted from various external sensors and controls the motors by various kinds of logic. Generally, the ECU calculates a driving current for driving a motor by using a steering torque detected through a torque sensor or the like in an MCU (Micro Controller Unit) contained therein and calculates the driving current by using two or more switches and batteries And supplies the drive current to the motor. At this time, a current sensor is connected between the switch and the battery motor to detect the current flowing in the motor. Such an IC device such as a Hall sensor can be used as a means for detecting a motor current. However, there is a problem that the manufacturing cost is increased and the precision of current detection is deteriorated due to a failure or the like. Therefore, a means for detecting a motor current using a shunt resistor is mainly used.

A motor control device capable of detecting a failure of an amplifier or an offset circuit by detecting a motor current using a shunt resistor has been proposed. However, although it is possible to detect whether one amplifier is faulty, there is a problem that it is not possible to detect that a plurality of amplifiers fail at the same time (common mode failure).

Japanese Patent Laid-Open No. 2003-107112A (September 28, 2003)

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a motor control apparatus and method for detecting a failure of a plurality of amplifiers at the same time .

Other features and advantages of the invention will be set forth in the description which follows, or may be obvious to those skilled in the art from the description and the claims.

According to an aspect of the present invention, there is provided a motor control apparatus including a current sensor for detecting a current supplied to a motor by a motor driving unit, a battery for supplying power to the motor driving unit, And a control unit that converts the output voltage of the battery to first reference data, converts the positive output voltage of the motor to second reference data, and outputs the negative output voltage of the motor as third reference data And a control unit for determining generation of a back electromotive force of the motor based on the first to third reference data and controlling driving of the motor based on a determination result of the back electromotive force of the motor do.

The voltage detecting unit of the motor control apparatus according to an embodiment of the present invention may include a first amplifying unit and a second amplifying unit for amplifying and outputting a voltage output from the current sensor, And a first offset unit and a second offset unit, each of which outputs an offset voltage.

The control unit of the motor control apparatus according to an embodiment of the present invention includes a determination unit that determines whether the output voltage of the first offset unit and the output voltage of the second offset unit are included in the set offset voltage range.

The reference data generator of the motor control apparatus according to the embodiment of the present invention converts the output voltage of the battery into first reference data, converts the positive output voltage of the motor to second reference data, And converts the output voltage into third reference data.

The determination unit of the motor control apparatus according to the embodiment of the present invention calculates the difference between the absolute value of the difference between the second reference data and the third reference data and the size of the first reference data, Compare.

[Equation 1]

The first reference data < the second reference data - the third reference data &

If the condition of Equation (1) is satisfied, it is determined that a back electromotive force is generated in the motor. Conversely, if the condition of Equation (1) is not satisfied, it is determined that no back electromotive force is generated in the motor.

The determination unit of the motor control apparatus according to an embodiment of the present invention may be configured such that when the output of the first offset unit is larger than the output of the first amplifier (AMP1 <offset1) in a state in which no counter electromotive force is generated in the motor, common mode failure is judged to have occurred.

The determination unit of the motor control apparatus according to an embodiment of the present invention may be configured such that when the output of the second offset unit is larger than the output of the second amplifier (AMP2 <offset2) in a state where no counter electromotive force is generated in the motor, common mode failure is judged to have occurred.

The controller of the motor control apparatus according to the present invention immediately stops driving the motor when a common mode failure occurs and displays an alarm of electric power steering by turning on a warning sound or a separate warning light .

The control unit of the motor control apparatus according to an embodiment of the present invention may be configured such that when the output of the first offset unit is larger than the output of the first amplifier (AMP1 <offset1) and when the output of the second offset unit is larger than the output of the second amplifier (AMP2 < offset2), and determines that a common mode failure occurs when the failure occurrence count is equal to or greater than a threshold value.

A motor control apparatus and method according to an embodiment of the present invention can detect that a plurality of amplifiers fail at the same time (common mode failure detection) and cope with a failure occurrence.

In addition, other features and advantages of the present invention may be newly understood through embodiments of the present invention.

1 is a view showing a motor control apparatus according to an embodiment of the present invention.
Fig. 2 is a view showing the control unit shown in Fig. 1. Fig.
3 is a diagram illustrating a motor control method according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

If any part is referred to as being "on" another part, it may be directly on the other part or may be accompanied by another part therebetween. In contrast, when a section is referred to as being "directly above" another section, no other section is involved.

The terms first, second and third, etc. are used to describe various portions, components, regions, layers and / or sections, but are not limited thereto. These terms are only used to distinguish any moiety, element, region, layer or section from another moiety, moiety, region, layer or section. Thus, a first portion, component, region, layer or section described below may be referred to as a second portion, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified and that the presence or absence of other features, regions, integers, steps, operations, elements, and / It does not exclude addition.

Terms indicating relative space such as "below "," above ", and the like may be used to more easily describe the relationship to other portions of a portion shown in the figures. These terms are intended to include other meanings or acts of the apparatus in use, as well as intended meanings in the drawings. For example, when inverting a device in the figures, certain portions that are described as being "below" other portions are described as being "above " other portions. Thus, an exemplary term "below" includes both up and down directions. The device can be rotated by 90 degrees or rotated at different angles, and terms indicating relative space are interpreted accordingly.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Commonly used predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

FIG. 1 is a view showing a motor control apparatus according to an embodiment of the present invention, and FIG. 2 is a view showing the control unit shown in FIG.

Referring to FIGS. 1 and 2, a motor control apparatus according to an embodiment of the present invention includes a voltage detector 100 and a controller 200. The voltage detector 100 includes a first offset unit 110, a second offset unit 120, an amplification unit 130, and a current sensor 140. The control unit 200 includes a plurality of analog-to-digital converters 211 to 217, a determination unit 220, a storage unit 230, a first current calculation unit 240, a second current calculation unit 250, A relay command generation unit 260 and a relay control unit 270. In addition, the controller 200 includes a counter to distinguish between a common mode failure and an error of a minute signal that is temporarily generated or an abnormal signal generation. When the controller 200 determines that a failure has occurred using the counter, Increase by 1.

The control unit 200 controls the motor driving unit 160 to supply the driving current to the motor 150 based on the output voltage of the voltage detecting unit 100. Hereinafter the analog digital converter will be referred to as an ' Will be referred to herein.

The relay 190 is turned on or turned off based on a relay control signal RCS input from the controller 200 and is turned on or off based on a driving current To the motor driving unit 160. The supply of drive current to the motor driver 160 is cut off when the relay 190 is turned off.

The motor driving unit 160 supplies a driving current to the motor 150. The motor driving unit 160 converts the driving current supplied from the battery 170 into a motor driving current and supplies the motor driving current to the motor 150. At this time, the motor driving unit 160 generates a driving current corresponding to the driving current value calculated by the controller 200, and supplies the driving current to the motor 150.

Here, the motor driving unit 160 includes four FETs A, B, C, and D, and can drive the motor 150 by switching FETs. That is, the motor driving unit 160 is constituted by an H-bridge circuit, and can drive the motor 150 by switching FETs by PWM (Pulse Width Modulation).

The regulator 180 converts the voltage supplied from the battery 170 to be suitable for driving the amplification unit 130 and the control unit 200 and outputs the converted voltage to the amplification unit 130 and the control unit 200, Supply.

The current sensor 140 senses a current flowing through the motor 150. The current sensor 140 may be a shunt resistor for detecting a shunt voltage by applying a shunt current output from the motor driver 160. [ Accordingly, the current sensor 140 detects the shunt voltage applied by the load current of the motor driver 160. [

The amplifying unit 130 includes a first amplifier 132 and an AMP 1 and a second amplifier 134 and AMP 2. In FIG. 1, the amplifying unit 130 includes two amplifiers 132 and 134 and is composed of two channels. However, the amplifying unit 130 may have three or more channels.

The first offset unit 110 outputs a first offset voltage, and the second offset unit 120 outputs a second offset voltage. The first offset unit 110 is connected to the first amplifier 132 and the second offset unit 120 is connected to the second amplifier 134. The first offset voltage output from the first offset unit 110 is supplied to the first amplifier 132 and the control unit 200. The second offset voltage outputted from the second offset unit 120 is supplied to the second amplifier 134 and the control unit 200.

The first amplifier 132 amplifies the shunt voltage output from the current sensor 140 and the first offset voltage output from the first offset unit 110 and outputs the amplified voltage to the control unit 200.

The second amplifier 134 amplifies the shunt voltage output from the current sensor 140 and the second offset voltage output from the second offset unit 120 and then outputs the amplified voltage to the control unit 200.

The control unit 200 controls the motor driving unit 160 so that the driving current is supplied to the motor 150 and adjusts the driving current based on the motor current detected by the voltage detecting unit.

As shown in FIG. 2, the control unit 200 is an apparatus for performing main control in the ECU. The control unit 200 controls the drive current by using the detected motor current and supplies the adjusted drive current to the motor 150 A storage unit for storing data and software for performing control, and a micro controller unit (MUC) for executing the software.

The control unit 200 includes an ADC unit 210, a determination unit 220, a storage unit 230, a first current calculation unit 240, a second current calculation unit 250, a relay instruction generation unit 260, And a control unit 270. The ADC unit 210 includes first to seventh ADCs 211 to 217.

The storage unit 230 stores a first reference voltage and a second reference voltage for checking whether the first offset voltage of the first offset unit 110 and the second offset voltage of the second offset unit 120 are normally output do.

The first ADC 211 included in the control unit 200 converts the first offset voltage output from the first offset unit 110 into the first digital signal V1 and outputs the first digital signal V1 to the determination unit 220, And the first current calculation unit 240. [

The second ADC 212 included in the control unit 200 converts the second offset voltage output from the second offset unit 120 into a second digital signal V2 and outputs the second digital signal V2 to the storage unit 230 and the first current calculation unit 230. [ (240).

The second ADC 212 included in the control unit 200 converts the voltage output from the first amplifier 132 into a third digital signal V3 and outputs the third digital signal V3 to the first current calculator 240 Supply.

The fourth ADC 214 included in the controller 200 converts the voltage output from the second amplifier 134 into a fourth digital signal V4 and supplies the fourth digital signal V4 to the first current calculator 240. [

The first current calculator 240 receives the output of the first ADC 211, the output of the second ADC 212, the output of the third ADC 213 and the output of the fourth ADC 214, 1 ADC 211 to the output current of the first offset unit 110. [ Further, the output of the second ADC 212 is converted into the output current of the second offset unit 120. Further, the output of the third ADC 213 is converted into the output current of the first amplifier 132. Further, the output of the fourth ADC 214 is converted into the output current of the second amplifier 134.

The first current calculator 240 may calculate the difference between the output current of the first offset unit 110 and the output current of the first amplifier 132 as a first shunt current. Further, the difference between the output current of the second offset unit 120 and the output current of the second amplifier 134 can be calculated as the second shunt current.

Accordingly, the first current calculator 240 can measure the current flowing to the current sensor, that is, the shunt current, with each of the converted output currents. The shunt current may be a first shunt current which is a difference between the output current of the first offset unit 110 and the output current of the first amplifier 132. [ The shunt current may be a second shunt current which is a difference between the output current of the second offset unit 120 and the output current of the second amplifier 134. In the present invention, either the first shunt current or the second shunt current can be used as the shunt current.

For example, when the first offset voltage output from the first offset unit 110 is out of the allowable range, the controller 200 stops the operation of the first offset unit 110. At this time, the second shunt current calculated based on the difference between the output current of the second offset unit 120 and the output current of the second amplifier 134 can be used as the cent current of the motor control apparatus.

The determination unit 220 determines whether the first offset voltage and the second offset voltage are normally output including the tolerance. For example, if the first reference voltage and the second reference voltage are each 1 [V] and the set tolerance is about 10% or less, the first offset voltage and the second offset voltage are valid within 0.9 to 1.1 [V] Can be operated.

The determination unit 220 determines the first offset voltage output from the first offset unit 110 and the first offset voltage output from the second offset unit 120 using the first reference voltage and the second reference voltage stored in the storage unit 230, It is determined whether or not the second offset voltage is valid. Although the storage unit 230 is shown as an independent configuration in FIG. 2, the determination unit 220 may store the first reference voltage and the second reference voltage to determine whether the first offset voltage and the second offset voltage are valid It is possible.

If the first offset unit 110 outputs an offset voltage that is out of the allowable range of the first reference voltage, it can be determined that the first offset unit 110 has failed. At this time, if the output voltage of the second offset unit 120 does not exceed the allowable range, the operation of the first offset unit 110 can be stopped and the second offset unit 120 can be continuously operated.

In contrast, if the second offset unit 120 outputs an offset voltage that is out of the allowable range of the second reference voltage, it can be determined that the first offset unit 110 has failed. At this time, if the output voltage of the first offset unit 110 does not exceed the allowable range, the operation of the second offset unit 120 can be stopped and the first offset unit 110 can be continuously operated.

Here, the determination unit 220 may determine whether the difference between the output voltage of the first amplifier 132 and the output voltage of the second amplifier 134 is within the set amplification voltage difference range. That is, the set amplification voltage difference is a criterion for determining whether the first amplifier 132 and the second amplifier 134 output the normal voltage. In this case, the set amplification voltage difference is determined by the difference between the amplification voltages of the first amplifier 132 and the second amplifier 134 It may indicate a criterion of an acceptable error range for the output voltage difference. The difference between the output voltage of the first amplifier 132 and the output voltage of the second amplifier 134 is in the range of 0.9 to 1.1 V. If the set amplification voltage difference is 1 [V] and the set tolerance is about 10% As shown in FIG.

If the output voltage difference between the first amplifier 132 and the second amplifier 134 outputs a voltage that is out of the set amplification voltage difference range, either one of the first amplifier 132 or the second amplifier 134 is faulty It can be judged. In this case, if it is determined that the first offset unit 110 is malfunctioning, the first amplifier 132 may be regarded as malfunctioning, so that the operation of the first amplifier 132 is stopped and the second amplifier 134 Can continue to operate.

As another example, when the second offset voltage output from the second offset unit 120 is out of the allowable range, the controller 200 stops the operation of the second offset unit 120. [ At this time, the first shunt current calculated based on the difference between the output current of the first offset unit 110 and the output current of the first amplifier 132 can be used as the cent current of the motor control apparatus.

If the output voltage difference between the first amplifier 132 and the second amplifier 134 outputs a voltage that is out of the set amplification voltage difference range, either one of the first amplifier 132 or the second amplifier 134 is faulty It can be judged. In this case, if it is determined that the second offset unit 120 is malfunctioning, the second amplifier 134 may be regarded as malfunctioning. Therefore, the operation of the second amplifier 134 is stopped and the first amplifier 132 is continuously operated . Accordingly, in the case of including only one amplifier, it can not be determined if the amplifier fails. However, according to the embodiment of the present invention including two amplifiers, the output voltage of the first amplifier 132 and the output voltage of the second amplifier 134, It is possible to determine whether the first offset unit 110 and the second offset unit 120 operate normally by determining whether the difference between the output voltages of the first offset unit 110 and the second offset unit 120 is within the set amplification voltage difference range. Also, it is possible to determine whether the first amplifier 132 and the second amplifier 134 operate normally. In addition, when one of the first amplifier 132 and the second amplifier 134 fails, the motor 150 and the controller 200 can operate normally using an amplifier that operates normally.

In order to detect that the first offset unit 110 and the second offset unit 120 fail at the same time or to detect that two amplifiers fail at the same time, two one-channel amplifiers may be applied, Other problems such as an increase in cost may occur. In particular, the prior art could not determine which amplifier failed if the output of the first amplifier and (AMP1 out) and the output of the second amplifier (AMP2 out) were the same or similar.

The motor control apparatus according to the embodiment of the present invention includes a first offset unit 110 and a second offset unit 120 using a reference data generation unit 150 when an amplifier unit 130 including a two- ) Fails at the same time (common mode failure). In addition, even when the first amplifier 132 and the second amplifier 134 fail at the same time, it can be detected.

The second ADC 154 of the reference data generating unit 150 converts the voltage (MOT V +) of the positive terminal of the motor 150 into second reference data and outputs the converted second reference data to the control unit 200 (220).

The third ADC 156 of the reference data generator 150 converts the voltage (MOT V-) of the negative terminal of the motor 150 into the third reference data and outputs the converted third reference data to the controller 200 And supplies it to the determination unit 220.

The fifth ADC 215 converts the voltage (MOT V-) of the negative (-) terminal of the motor 150 into the first reference data and supplies the first reference data to the determination unit 220.

The sixth ADC 216 converts the voltage (MOT V +) of the positive terminal of the motor 150 into second reference data and supplies the second reference data to the determination unit 220.

The seventh ADC 217 converts the output voltage of the battery 170 to third reference data and supplies the third reference data to the determination unit 220. [

The determination unit 220 determines whether or not the first reference data supplied from the fifth ADC 215, the second reference data supplied from the sixth ADC 216, and the third reference data supplied from the seventh ADC 217 It is determined whether the first offset unit 110 and the second offset unit 120 fail simultaneously. The determination unit 220 determines whether or not the first reference data supplied from the fifth ADC 215, the second reference data supplied from the sixth ADC 216, the third reference data supplied from the seventh ADC 217, It is determined whether the first amplifier 132 and the second amplifier 134 fail at the same time.

When the output voltages of the first amplifier 132 and the second amplifier 134 are floating when the output voltages of the first offset unit 110 and the second offset unit 120 are set to 1 V, The output values of the first amplifier 132 and the second amplifier 134 are equal to each other or within the error range. Therefore, the first offset unit 110 and the second offset unit 120 can not detect a common mode failure that fails at the same time. Also, the first amplifier 132 and the second amplifier 134 can not detect a common mode failure that fails at the same time.

More specifically, when the output of the first offset unit 110 is larger than the output of the first amplifier 132 (AMP1 <offset1) or the output of the second offset unit 120 is larger than the output of the second amplifier 134 (AMP2 < offset2) may occur. A common mode failure can not be detected in such a case because a back electromotive voltage may be generated due to the high speed travel of the motor 150. [

The determination unit 220 outputs the first reference data supplied from the fifth ADC 215 and the second reference data supplied from the sixth ADC 216 to the third reference data supplied from the seventh ADC 217, The presence or absence of a counter electromotive force of the motor 150 is determined. If the output of the first offset unit 110 is larger than the output of the first amplifier 132 (AMP1 <offset1) or the output of the second amplifier 134 is smaller than the output of the second amplifier 134 When the output of the 2-offset unit 120 is large (AMP2 <offset2), it is determined that a common mode failure has occurred.

The determination unit 220 uses the output voltage of the battery 170, the voltage (MOT V +) of the positive terminal of the motor 150 and the voltage (MOT V-) of the negative terminal of the motor 150 And determines whether there is a counter electromotive force of the motor 150. [

Specifically, the output voltage of the battery 170, that is, the first reference data and the magnitudes of the output voltages (MOT V + and MOT V-) of the motor 150 are compared. In this case, the output voltage of the battery 170, that is, the third reference data, the positive (+) output (first reference data) and the negative (-) output (MOT +) - (MOT-)) of the difference of the difference between the reference values (|

[Equation 1]

Third reference data < | first reference data - second reference data |

If the condition of Equation (1) is satisfied, the output voltage of the motor 150 is larger than the output voltage of the battery 170. In this case, the determination unit 220 determines that a back electromotive force .

If the condition of Equation (1) is not satisfied, the output voltage of the battery 170 is equal to the output voltage of the motor 150 or the output voltage of the battery 170 is greater than the output voltage of the motor 150 In this case, the determination unit 220 may determine that no counter electromotive force has occurred in the motor 150. [

The determination unit 220 determines whether the output of the first offset unit 110 is larger than the output of the first amplifier 132 (AMP1 <offset1) in the state where no counter electromotive force is generated in the motor 150, mode failure occurs.

When the output of the second offset unit 120 is larger than the output of the second amplifier 134 (AMP2 <offset2) in the state where the motor 150 does not generate the back electromotive force, the determination unit 220 determines that the common mode (common mode) failure has occurred.

 If it is determined that a common mode failure has occurred, the relay command generating unit 260 generates a relay off command for immediately stopping the driving of the motor 150. The relay off command generated by the relay command generator 260 is supplied to the relay controller 270. The relay control unit 270 turns off the relay in accordance with the input relay off command and blocks the output voltage of the battery 170 from being supplied to the motor driving unit 160. At the same time, the controller 200 may indicate that the EPS can not be operated by lighting a warning sound or a separate warning light so that the driver can recognize that the electric power steering (EPS) is disabled.

In the description with reference to FIG. 2, the first current calculating unit 240 and the second current calculating unit 250 are described as being independent of each other. However, the present invention is not limited to this, and the first current calculating unit 240 and the second current calculating unit 250 may be integrated and applied in one configuration.

3 is a diagram illustrating a motor control method according to an embodiment of the present invention.

Referring to FIG. 3, in order to detect a common mode failure, the output voltage of the motor 150 is compared with the output voltage of the battery 170 to determine whether a back electromotive force is generated in the motor 150 (S10) .

The determination unit 220 compares the voltage (first reference data) of the negative terminal of the motor 150 supplied from the fifth ADC 215 with the voltage of the positive terminal of the motor 150 supplied from the sixth ADC 216 It is determined whether a back electromotive force is generated in the motor 150 using the voltage of the positive terminal (second reference data) of the first ADC 217 and the voltage (third reference data) of the battery 170 supplied from the seventh ADC 217. At this time, the absolute value (| first reference data | second reference data | = | motor voltage |) of the voltage difference between the negative (-) terminal of the motor 150 and the positive . Then, it is determined whether the battery voltage is greater than the absolute value of the motor voltage.

If the battery voltage is greater than the absolute value of the motor voltage, the motor 150 determines that no counter electromotive force has occurred. On the contrary, when the absolute value of the battery voltage is equal to the absolute value of the motor voltage, or when the battery voltage is smaller than the absolute value of the motor voltage, it is determined that the motor 150 generates a counter electromotive force.

Specifically, the output voltage of the battery 170, that is, the magnitude of the third reference data and the output voltage of the motor 150 (first reference data - second reference data |) is compared. (MOT +) of the difference between the output voltage of the battery 170, that is, the third reference data, and the positive (+) and negative (-) outputs of the motor 150, ) - (MOT-) |).

If the condition of Equation (1) is satisfied, the output voltage of the motor 150 is greater than the output voltage of the battery 170. In this case, it can be determined that the motor 150 generates a back electromotive force.

Conversely, if the condition of Equation (1) is not satisfied, the output voltage of the battery 170 is equal to the output voltage of the motor 150 or the output voltage of the battery 170 is greater than the output voltage of the motor 150, In this case, it can be determined that the motor 150 does not generate the back electromotive force.

If no counter electromotive force is generated in the motor 150, the determination unit 220 determines whether the output of the first offset unit 110 is larger than the output of the first amplifier 132 (AMP1 <offset1) (S20 ). The determination unit 220 determines whether the output of the second offset unit 120 is greater than the output of the second amplifier 134 (AMP2 <offset2) (S20).

If it is determined that the output of the first amplifier 132 is equal to the output of the first offset unit 110 or the output of the first amplifier 132 is larger than the output of the first offset unit 110 The determination unit 220 determines that the failure is not a common mode failure. Then, the failure count increment value is set to 0 so as not to increase the failure occurrence count (S30).

Similarly, if the output of the second amplifier 134 is equal to the output of the second offset unit 120 or the output of the second amplifier 142 is the same as the output of the second offset unit 120 The determination unit 220 determines that the failure is not a common mode failure. Then, the failure count increment value is set to 0 so as not to increase the failure occurrence count (S30).

Here, in order to increase the accuracy of the common mode failure judgment, the fault occurrence count is applied, and it is judged that the normal operation of the EPS is a common mode common mode failure due to a minute signal error or an abnormal signal generation . That is, when the failure occurrence count satisfies a certain reference value, the failure occurrence count is applied so that the failure of the common mode is judged.

If the motor 150 does not generate a counter electromotive force, the determination unit 220 determines that the output of the first offset unit 110 is larger than the output of the first amplifier 132 (AMP1 <offset1) The fault occurrence count is increased (S40). At this time, the fault count increment value can be set to 1.

The determination unit 220 determines that the output of the second offset unit 120 is larger than the output of the second amplifier 134 in the case where the back electromotive force is not generated in the motor 150, offset1), the fault occurrence count is increased (S40). At this time, the fault count increment value can be set to 1.

Then, it is determined whether the failure count is equal to or greater than a threshold (fail count> = threshold) (S50).

As a result of the determination in S50, when the failure occurrence count is less than the threshold value, it is determined that the failure is not a common mode failure, and the EPS operation is normally performed.

On the other hand, if it is determined in step S50 that the failure count is equal to or greater than the threshold value (fail count> = threshold), it is determined that a common mode failure has occurred. Then, the controller 200 turns off the relay 190 through the relay control signal RCS to block the supply of the driving voltage to the motor 150. Thereby immediately stopping the driving of the motor 150. At the same time, it is possible to indicate that the EPS can not be operated by lighting a warning sound or a separate warning light so that the driver can recognize the EPS failure (S60).

A motor control apparatus and method according to an embodiment of the present invention can detect that a plurality of amplifiers fail at the same time (common mode failure detection) and cope with a failure occurrence.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and their equivalents. Only. It is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. .

100: voltage detection unit 110: first offset unit
120: second offset unit 130: amplification unit
132: first amplifier 134: second amplifier
140: current sensor 150: motor
160: motor drive unit 170: battery
180: regulator 190: relay
200: control unit 210: ADC unit
211: first ADC 212: second ADC
213: third ADC 214: fourth ADC
215: fifth ADC 216: sixth ADC
217: seventh ADC 220:
230: storage unit 240: first current calculation unit
250: second current calculator 260: relay command generator
270:

Claims (9)

A current sensor for detecting a current supplied to the motor by the motor driving unit;
A battery for supplying power to the motor driving unit;
A voltage detector for detecting a voltage output from the current sensor;
A reference data generator for converting the output voltage of the battery into first reference data, converting the positive output voltage of the motor to second reference data, and converting the negative output voltage of the motor to third reference data; And
And a controller for determining generation of a counter electromotive force of the motor on the basis of the first to third reference data and for controlling driving of the motor based on a determination result of a counter electromotive force of the motor. The apparatus of claim 1, wherein the voltage detector comprises:
A first amplifying unit and a second amplifying unit for amplifying and outputting a voltage output from the current sensor; And
And a first offset unit and a second offset unit connected to the first amplification unit and the second amplification unit, respectively, for outputting an offset voltage. 3. The apparatus of claim 2,
And a determination unit determining whether the output voltage of the first offset unit and the output voltage of the second offset unit are included in the set offset voltage range. 4. The apparatus of claim 3,
Converts the output voltage of the battery into first reference data,
Converts the positive output voltage of the motor to second reference data,
And converts the negative output voltage of the motor into third reference data. 5. The apparatus of claim 4,
The absolute value of the difference between the second reference data and the third reference data is compared with the size of the first reference data using Equation 1 below,
(1)
The first reference data < the second reference data - the third reference data &
The controller determines that a back electromotive force is generated in the motor if the condition of Equation (1) is satisfied, and on the contrary, it determines that no back electromotive force is generated in the motor if the condition of Equation (1) is not satisfied. 6. The apparatus of claim 5,
And determines that a common mode failure occurs when the output of the first offset unit is larger than the output of the first amplifier (AMP1 <offset1) in a state in which the motor does not generate a counter electromotive force. 6. The apparatus of claim 5,
Wherein when the output of the second offset unit is larger than the output of the second amplifier (AMP2 <offset2), the common control unit determines that a common mode failure occurs in a state where no counter electromotive force is generated in the motor. 7. The apparatus as claimed in claim 6 or 7,
And stops the driving of the motor immediately when a common mode failure occurs and displays a warning sound or another warning light to indicate that EPS (electric power steering) is disabled. 7. The apparatus as claimed in claim 6 or 7,
When the output of the first offset portion is larger than the output of the first amplifier (AMP1 <offset1) and when the output of the second offset portion is larger than the output of the second amplifier (AMP2 <offset2), the fault count increment value is increased A counter,
And determines that a common mode failure occurs when the failure occurrence count is equal to or greater than a threshold value.

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