JP2006069352A - Electric power steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power steering device capable of preventing the steering feeling from being impaired even when an ignition switch is turned off, or the electric power steering device is determined to be abnormal in the failure diagnosis. <P>SOLUTION: When a stop instruction signal such as an OFF signal of an ignition switch and abnormality information by the failure diagnosis is detected, the drive of an assist motor 6 is stopped if the absolute value of the target current Im* is not more than the determination current Im0, or if the predetermined time is elapsed. In addition, the assist motor 6 is controlled based on the proportional gain Kp and the integration gain Ki which are gradually reduced as the time is elapsed before the drive of the assist motor 6 is stopped. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electric power steering apparatus.

2. Description of the Related Art Conventionally, an electric power steering apparatus performs proportional / integral control (PI control) based on a deviation between a target current of an assist motor calculated from, for example, steering torque and vehicle speed, and an electric motor current flowing through the assist motor (for example, , See Patent Document 1).
JP-A-8-332969

  By the way, the electric power steering apparatus immediately stops the driving of the assist motor when the ignition switch is turned off or when an abnormality is diagnosed by the failure diagnosis. For this reason, for example, when the driving of the assist motor is stopped in a state where steering torque is applied to the steering wheel, the steering assist force that has been applied by the assist motor suddenly decreases, and thus the steering force by the driver suddenly decreases. It increased and the steering feeling was damaged.

  The present invention has been made in view of such circumstances, and an electric power steering system that does not impair the steering feeling even when the ignition switch is turned off or when it is determined to be abnormal by failure diagnosis. An object is to provide an apparatus.

  An electric power steering apparatus according to the present invention includes an assist motor for assisting a steering force, steering torque detection means for detecting a steering torque applied to a steering shaft, and a target for setting a target current to be supplied to the assist motor based on the steering torque. Current setting means; motor current detection means for detecting motor current flowing through the assist motor; proportional-integral control means including at least one of a proportional element and an integral element based on a deviation between the target current and the motor current; Motor driving means for driving the assist motor based on the output of the proportional-integral control means. Further, the characteristic features of the electric power steering apparatus of the present invention further include a stop instruction signal detecting means for detecting a stop instruction signal of the assist motor, and the proportional gain and / or when the stop instruction signal is detected. Gain setting means for reducing the integral gain with time, and drive stop means for stopping the driving of the assist motor when a predetermined time has elapsed after detecting the stop instruction signal.

  According to the electric power steering apparatus of the present invention, when the stop instruction signal is detected, the drive of the assist motor is not immediately stopped, and the proportional gain and / or the integral gain are decreased with time. That is, the steering follow-up performance is gradually lowered by decreasing the proportional gain and / or the integral gain with time. As a result, a steady deviation is gradually generated, and the motor current flowing through the assist motor gradually decreases with respect to the target current. That is, the steering assist force gradually decreases with time. Then, the driving of the assist motor is stopped when a predetermined time has elapsed since the stop instruction signal was detected.

  Thus, since the steering assist force by the assist motor is applied until a predetermined time elapses after the stop instruction signal is detected, the steering assist force does not decrease rapidly. Further, since the steering assist force is gradually reduced as time elapses after the stop instruction signal is detected, even if the assist motor is stopped when a predetermined time has elapsed, the steering force by the driver is The steering feeling can be improved without a sharp increase.

  Next, the present invention will be described in more detail with reference to embodiments.

  As described above, the electric power steering apparatus of the present invention includes an assist motor, steering torque detection means, target current setting means, motor current detection means, proportional-integral control means, motor drive means, and stop instruction signal. A detection unit, a gain setting unit, and a drive stop unit are provided.

(1) Assist motor / motor drive means Here, as the assist motor, for example, a DC motor, a brushless DC motor, or the like can be used. In the case where a brushless DC motor is used as the assist motor, the motor driving means includes an inverter circuit including a plurality of switching elements, a PWM output unit that outputs a PWM signal, and the like. When a DC motor is used as the assist electric motor, the electric motor driving means includes a full bridge circuit having a plurality of switching elements, a PWM output unit that outputs a PWM signal, and the like.

(2) Steering torque detection means / proportional integral control means The steering torque detection means may be a steering torque sensor capable of detecting steering torque. This steering torque sensor is provided on, for example, a steering shaft. Further, the proportional-plus-integral control means may be any of a proportional element only, an integral element only, a proportional element and an integral element.

(3) Drive stop means The drive stop means drives the assist motor when a predetermined time has elapsed since the stop instruction signal was detected or when the steering torque or the target current is equal to or less than a predetermined threshold. You may make it stop. In other words, not only the elapsed time since the detection of the stop instruction signal but also the driving of the assist motor is stopped not only when the steering torque is equal to or less than the predetermined torque threshold or the target current is equal to or less than the predetermined current threshold. In other words, even if the predetermined time has not elapsed since the detection of the stop instruction signal, the driving of the assist motor is stopped when the steering torque or the target current is equal to or less than the predetermined threshold.

  Here, when the steering torque is equal to or smaller than the predetermined torque threshold value or when the target current is equal to or smaller than the predetermined current threshold value, the steering assist force itself by the assist motor is in a small state. That is, in the above case, even if the assist motor is stopped to reduce the steering assist force, the steering feeling is not impaired. Therefore, the drive of the assist motor can be stopped as fast as possible without impairing the steering feeling. As a result, the power consumption of the battery can be reduced.

(4) Stop instruction signal and gain Further, the stop instruction signal is an abnormality detection signal for detecting a plurality of abnormal states of the electric power steering apparatus, and the proportional gain and / or the integral gain are respectively the abnormality You may make it differ according to a state. Further, the stop instruction signal is an abnormality detection signal for detecting at least one abnormal state of the electric power steering apparatus and an off signal of an ignition switch, and the proportional gain and / or the integral gain are the abnormal state and the You may make it differ according to an OFF signal.

  Here, the abnormal state is an abnormal state such as a steering torque detection means, a temperature sensor for detecting a temperature abnormality of the assist motor, a current voltage detection sensor, or the like. The proportional gain and / or the integral gain are made different depending on the type of abnormal state.

  Further, the proportional gain and / or the integral gain may be decreased linearly with the passage of time, may be decreased linearly, or may be decreased linearly according to an abnormal state, or The curve may be reduced. As a result, the gain can be reduced to an appropriate value for an abnormal state or an OFF signal of the ignition switch.

(5) Stop instruction signal and predetermined time The stop instruction signal is an abnormality detection signal for detecting a plurality of abnormal states of the electric power steering device, and the predetermined time varies depending on each abnormal state. You may do it. Further, the stop instruction signal is an abnormality detection signal for detecting at least one abnormal state of the electric power steering device and an off signal of an ignition switch, and the predetermined time varies depending on the abnormal state and the off signal. You may do it. Thereby, the driving of the assist motor can be stopped when an appropriate time has elapsed in accordance with the abnormal state or the OFF signal of the ignition switch.

  Next, an example is given and the present invention is explained more concretely with reference to drawings. A block diagram of the overall configuration of the electric power steering apparatus of the present embodiment is shown in FIG. As shown in FIG. 1, the electric power steering apparatus includes a steering torque sensor (steering torque detection means) 1, a target current setting unit (target current setting means) 2, a subtractor 3, and a PI control unit (proportional integral control). Means) 4, inverter drive unit (motor drive unit) 5, assist motor 6, motor current detection unit (motor current detection unit) 7, IG switch 8, failure diagnosis unit 9, and motor stop processing unit 10. It consists of. Hereinafter, each part which comprises an electric power steering device is demonstrated in detail.

(1) Steering torque sensor 1
The steering torque sensor 1 is a sensor that detects a steering torque Ts applied to a steering shaft (not shown). Here, the steering shaft connected to the steering wheel includes a torsion bar. A steering torque sensor 1 is attached to the torsion bar. When the steering wheel rotates, a rotational force is applied to the torsion bar, and the torsion bar is twisted according to the applied rotational force. The steering torque applied to the steering shaft corresponding to the twist of the torsion bar is detected by the steering torque sensor 1.

(2) Target current setting unit 2
The target current setting unit 2 first inputs the steering torque Ts detected by the steering torque sensor 1. And the phase compensation process of the inputted steering torque Ts is performed. Based on the steering torque Ts on which the phase compensation processing has been performed, a target current Im * to be supplied to the assist motor 6 is set. The target current Im * is set based on a target current map indicating the relationship of the target current Im * with respect to the steering torque Ts stored in advance.

(3) Subtractor 3
The subtractor 3 is a deviation current (deviation) ΔIm (= Im * −) obtained by subtracting a motor current Im detected by a motor current detection unit 7 described later from a target current Im * set by the target current setting unit 2. Im) is calculated.

(4) PI control unit 4
The PI control unit 4 receives the deviation current ΔIm calculated by the subtractor 3, performs proportional-integral control on the input deviation current ΔIm, and calculates a voltage command value Vm to be applied to the assist motor 6. In the proportional-integral control, the proportional gain Kp of the proportional element and the integral gain Ki of the integral element are set by the gain setting unit 104 described later. Further, as the proportional gain Kp and the integral gain Ki are larger, the motor current Im can be quickly converged to the target current Im *. That is, the larger the proportional gain Kp and the integral gain Ki, the better the followability.

(5) Inverter drive unit 5, assist motor 6, motor current detection unit 7
The inverter drive unit 5 includes a PWM signal generation unit and an inverter circuit unit. The PWM signal generation unit calculates a PWM signal based on the voltage command value Vm output from the PI control unit 4. The inverter circuit unit is composed of a plurality of switching elements. In the inverter circuit unit, each switching element is driven based on the PWM signal output from the PWM signal generation unit, and supplies current to the assist motor 6. By supplying current to the assist motor 6, the assist motor 6 generates a steering assist force. The assist motor 6 is, for example, a DC motor or a brushless DC motor. The motor current detector 7 detects the motor current Im flowing through the assist motor 6 and outputs the detected motor current Im to the subtracter 3.

(6) IG switch 8 and fault diagnosis unit 9
The IG switch (ignition switch) 8 is a switch for starting or stopping the driving of the engine or the like by turning on / off. When the IG switch 8 is turned off, the IG switch 8 outputs an IG switch off signal to the motor stop processing unit 10 described later.

  The failure diagnosis unit 9 diagnoses a failure of each part of the electric power steering apparatus. The failure diagnosis unit 9 diagnoses, for example, an excessive torque abnormality of the steering torque sensor 1, an abnormality of a temperature sensor (not shown) provided near the assist motor 6, an abnormality of a current voltage sensor, and the like. And the failure diagnosis part 9 outputs failure diagnosis information to the motor stop process part 10 mentioned later. Here, the failure diagnosis information includes failure type information such as a failure location and a failure reason. Since the failure diagnosis process is well known, detailed description thereof is omitted.

(7) Motor stop processing unit 10
The motor stop processing unit 10 inputs an IG switch-off signal from the IG switch 8 and inputs failure diagnosis information from the failure diagnosis unit 9. Further, the target current Im * is input from the target current setting unit 2.

  Then, the motor stop processing unit 10 sets the proportional gain Kp and the integral gain Ki of the PI control unit 4 based on the input IG switch-off signal, failure type information, and target current Im *. Further, the motor stop processing unit 10 performs a stop process of the assist motor 6 based on the input IG switch-off signal, failure type information, and target current Im *.

  Specifically, the motor stop processing unit 10 includes a stop instruction signal detection unit (stop instruction signal detection unit) 101, a target current value determination unit 102, a timer 103, and a gain setting unit (gain setting unit) 104. And an electric motor drive stop unit (drive stop means) 105. Hereinafter, each part which comprises the electric motor stop process part 10 is demonstrated in detail.

(7.1) Stop instruction signal detection unit 101
The stop instruction signal detection unit 101 detects a stop instruction signal of the assist motor 6 based on the IG switch off signal or the failure type information input from the IG switch 8 and the failure diagnosis unit 9. Here, the stop instruction signal is an IG switch-off signal input from the IG switch 8 and failure type information itself input from the failure diagnosis unit 9. When the stop instruction signal detection unit 101 detects the stop instruction signal, the stop instruction signal detection unit 101 outputs the detected stop instruction signal to the gain setting unit 104 or the like.

(7.2) Target current value determination unit 102
The target current value determination unit 102 inputs the target current Im * set by the target current setting unit 2. Then, the target current value determination unit 102 compares the absolute value of the input target current Im * with a determination current (predetermined current threshold) Im0 stored in advance, and the absolute value of the target current Im * is determined as the determination current. It is determined whether it is larger than Im0. Then, the target current value determination unit 102 outputs the determination result to the gain setting unit 104 and the motor drive stop unit 105 which will be described later. It should be noted that the determination current Im0 does not significantly increase the steering force by the driver even when the current supply to the assist motor 6 is interrupted when the current corresponding to the determination current Im0 is supplied to the assist motor 6. The current value is such that the steering feeling is not lowered.

(7.3) Timer 103
The timer 103 counts an elapsed time from when the stop instruction signal detection unit 101 detects a stop instruction signal. Specifically, the timer 103 starts counting up the timer counter t when a stop instruction signal is output from the stop instruction signal detection unit 101. Then, the timer 103 outputs the timer counter t to a gain setting unit 104 and a motor drive stop unit 105 which will be described later.

(7.4) Gain setting unit 104
The gain setting unit 104 is based on the stop instruction signal output from the stop instruction signal detection unit 101, the determination result output from the target current value determination unit 102, and the timer counter t output from the timer 103. 4 proportional gain Kp and integral gain Ki are set. Specifically, the gain setting unit 104 first sets the proportional gain Kp and the integral gain Ki of the PI control unit 4 to the normal state proportional gain (normal proportional gain) Kp1 and the normal state when the stop instruction signal is not output. Integral gain (normal integral gain) Ki1. Here, the normal state means a state that is different from a stop state when the assist motor 6 is stopped, and means a state that is not the stop state.

  Further, the gain setting unit 104 outputs the proportional gain Kp and the integral gain Ki of the PI control unit 4 when the stop instruction signal is output and the absolute value of the target current Im * is larger than the determination current Im0. Different stop proportional gain Kp2 and stop integral gain Ki2 are set according to the type of stop instruction signal. Here, the stop proportional gain Kp2 and the stop integral gain Ki2 have values smaller than the normal proportional gain Kp1 and the normal integral gain Ki1, respectively. Specifically, the stop proportional gain Kp2 and the stop integral gain Ki2 are set to values that become 0 (zero) when the timer counter t reaches the predetermined counter T1, for example. Further, the stop proportional gain Kp2 and the stop integral gain Ki2 are set so that the time required to reach 0 (zero) (corresponding to the predetermined counter T1) varies depending on the type of the stop instruction signal.

  For example, when the stop instruction signal is an off signal of the IG switch 8, the predetermined counter T1 is set to 5 sec, for example. When the stop instruction signal is abnormal information such as excessive torque of the steering torque sensor 1, the predetermined counter T1 is set to, for example, 500 msec. Further, when the stop instruction signal is abnormality information of the temperature sensor and the current / voltage detection sensor, the predetermined counter T1 is set to 2 sec, for example. In addition, various predetermined counters T1 are set according to the type of stop instruction signal. Depending on the type of failure information, the predetermined counter T1 may be set to 0 sec. In this way, the predetermined counter T1 is set so as to be suitable for the failure state and to improve the steering feeling.

(7.5) Motor drive stop unit 105
The electric motor drive stop unit 105 is based on the stop instruction signal output from the stop instruction signal detection unit 101, the determination result output from the target current value determination unit 102, and the timer counter t output from the timer 103. It is determined whether or not the drive No. 6 is stopped. Specifically, the motor drive stop unit 105 determines that the drive of the assist motor 6 is stopped when the stop instruction signal is output and the absolute value of the target current Im * is equal to or less than the determination current Im0. To do. In addition, when the stop instruction signal is output and the absolute value of the target current Im * is larger than the determination current Im0, the motor drive stop unit 105 further assists the motor 6 when the timer counter t reaches the predetermined counter T1. It is determined that the driving of is stopped.

  When it is determined that the drive of the assist motor 6 is to be stopped, the motor drive stop unit 105 performs a process of stopping the drive of the assist motor 6. The process of stopping the driving of the assist motor 6 is, for example, a process of opening a power supply relay (not shown) arranged between the inverter drive unit 5 and a power supply that supplies power to the inverter drive unit 5, or For example, the phase opening relay (not shown) disposed between the inverter driving unit 5 and the assist motor 6 is opened.

(8) Processing Operation of Motor Stop Processing Unit 10 Next, the processing operation of the motor stop processing unit 10 will be described with reference to FIGS. FIG. 2 is a flowchart showing the motor stop process. FIG. 3A shows a proportional gain setting coefficient G1 and an integral gain setting coefficient G2 for the timer counter t. FIG. 3B shows the proportional gain Kp for the timer counter t. FIG. 3C shows the integral gain Ki for the timer counter t.

  First, the motor stop processing unit 10 detects a stop instruction signal by the stop instruction signal detection unit 101 (step S1). Subsequently, it is determined whether or not a stop instruction signal is detected (step S2). When the stop instruction signal is not detected (step S2: No), the gain setting unit 104 sets the normal proportional gain Kp1 and the normal integral gain Ki1 as the proportional gain Kp and the integral element of the PI control unit 4. Is set as the integral gain Ki (step S3). Then, the process ends.

  On the other hand, when the stop instruction signal is detected (step S2: Yes), the target current value determination unit 102 reads the target current Im * (step S4). Subsequently, the target current value determination unit 102 compares the absolute value of the read target current Im * with a previously stored determination current Im0, and determines whether the absolute value of the target current Im * is greater than the determination current Im0. It is determined whether or not (step S5). Then, the determination result is output to the gain setting unit 104 and the motor drive stop unit 105.

  If the absolute value of the target current Im * is equal to or smaller than the determination current Im0 (step S5: No), the motor drive stop unit 105 performs a process of stopping the driving of the assist motor 6 (step S10). That is, when the stop instruction signal is detected and the absolute value of the target current Im * is equal to or less than the determination current Im0, the driving of the assist motor 6 is stopped.

  On the other hand, when the absolute value of the target current Im * is larger than the determination current Im0 (step S5: Yes), the gain setting unit 104 sets the proportional gain setting coefficient G1 and the integral gain according to the type of the stop instruction signal. A coefficient G2 and a predetermined counter T1 are set (step S6). Further, in the above case, the electric motor drive stop unit 105 sets a predetermined counter T1 (step S6). Here, the proportional gain setting coefficient G1 and the integral gain setting coefficient G2 are used when setting the stop proportional gain Kp2 and the stop integral gain Ki2, respectively. The predetermined counter T1 is used to determine whether or not to stop the assist motor 6 by comparing the timer 103 with the timer counter t.

  Here, the proportional gain setting coefficient G1 and the integral gain setting coefficient G2 will be described with reference to FIG. As shown in FIG. 3A, the proportional gain setting coefficient G1 and the integral gain setting coefficient G2 are linear so that they are 1 when the timer counter t is 0 and 0 when the timer counter t is the predetermined counter T1. The relationship decreases.

  Subsequently, the gain setting unit 104 calculates the stop proportional gain Kp2 and the stop integral gain Ki2 based on Equation 1. Then, the calculated stop proportional gain Kp2 and stop integral gain Ki2 are set as the proportional gain Kp of the proportional element and the integral gain Ki of the integral element of the PI control unit 4 (step S7).

  Here, as described above, the proportional gain setting coefficient G1 and the integral gain setting coefficient G2 are linearly decreased as the timer counter t increases. Accordingly, the stop proportional gain Kp2 and the stop integral gain Ki2 calculated based on Equation 1 become the normal proportional gain Kp1 and the normal integral gain Ki1 when the timer counter t is 0, as shown in FIGS. When the timer counter t increases linearly and reaches the predetermined counter T1, it becomes 0 (zero). That is, the stop proportional gain Kp2 and the stop integral gain Ki2 are smaller than the normal proportional gain Kp1 and the normal integral gain Ki1, respectively.

  Then, after setting the stop proportional gain Kp2 and the stop integral gain Ki2, the timer counter t of the timer 103 starts counting up (step S8). Subsequently, the motor drive stop unit 105 compares the timer counter t of the timer 103 with the predetermined counter T1 set as described above to determine whether the timer counter t is equal to or greater than the predetermined counter T1. (Step S9).

  If the timer counter t is smaller than the predetermined counter T1 (step S9: No), the process is terminated as it is. On the other hand, when the timer counter t reaches the predetermined counter T1 or more (step S9: Yes), the motor drive stop unit 105 performs a process of stopping the drive of the assist motor 6 (step S10). That is, when the time corresponding to the predetermined counter T1 has elapsed since the detection of the stop instruction signal, the driving of the assist motor 6 is stopped. Meanwhile, the proportional gain Kp and the integral gain Ki are decreased linearly with the passage of time.

(9) Modification of the above embodiment The motor stop processing unit 10 of the above embodiment determines whether or not the absolute value of the target current Im * is larger than the determination current Im0 in the target current value determination unit 102, and a gain setting unit Although the gain setting and the assist motor 6 stop process are performed based on the determination result in 104 and the motor drive stop unit 105, the present invention is not limited to this.

  For example, the target current value determination unit 102 of the above embodiment may be replaced with a steering torque value determination unit. The steering torque value determination unit inputs the steering torque Ts detected by the steering torque sensor 1. The steering torque value determination unit compares the absolute value of the input steering torque Ts with a determination torque value (predetermined torque threshold) Ts0 stored in advance, and the absolute value of the steering torque Ts is determined as the determination torque value Ts0. Determine if greater than. The determination result is output to the gain setting unit 104 and the motor drive stop unit 105. Even if the current supply to the assist motor 6 is interrupted when the current corresponding to the target current Im * set based on the determination torque value Ts0 is supplied to the assist motor 6, the determination torque value Ts0 The steering torque value is such that the steering feeling by the driver does not increase greatly and the steering feeling is not lowered.

  In this case, the gain setting unit 104 and the motor drive stop unit 105 perform gain setting and drive stop processing of the assist motor 6 based on the determination result by the steering torque value determination unit. Specifically, when the steering torque Ts is equal to or less than the determination torque value Ts0, the electric motor drive stop unit 105 performs a process of stopping the driving of the assist motor 6. Further, when the steering torque Ts is larger than the determination torque value Ts0, the processing after step S6 in FIG. 2 is performed.

  In addition, the gain setting unit 104 of the above embodiment sets the stop proportional gain Kp2 and the stop integral gain Ki2 based on Equation 1, but is not limited thereto. For example, the stop proportional gain Kp2 and the stop integral gain Ki2 may be determined based on a map of each gain with respect to the elapsed time stored in advance. Further, the stop proportional gain Kp2 and the stop integral gain Ki2 may be calculated on the basis of a relational expression or a map that decreases in a curve with time.

It is a block diagram of the whole structure of the electric power steering device of a present Example. It is a flowchart which shows an electric motor stop process. (A) It is a figure which shows the proportional gain setting coefficient G1 and the integral gain setting coefficient G2 with respect to the timer counter t. (B) It is a figure which shows the proportional gain Kp with respect to the timer counter t. (C) It is a figure which shows the integral gain Ki with respect to the timer counter t.

Explanation of symbols

1: Steering torque sensor (steering torque detection means) 2: Target current setting section (target current setting means) 3: Subtractor 4: PI control section (proportional integration control means) 5: Inverter drive section (motor drive) Means), 6: assist motor, 7: motor current detection unit (motor current detection unit), 8: IG switch, 9: failure diagnosis unit, 10: motor stop processing unit, 101: stop instruction signal detection unit (stop instruction signal) Detection means), 102: target current value determination section, 103: timer, 104: gain setting section (gain setting means), 105: motor drive stop section (drive stop means)

Claims (6)

An assist motor to assist the steering force;
Steering torque detecting means for detecting steering torque applied to the steering shaft;
Target current setting means for setting a target current to be supplied to the assist motor based on the steering torque;
Motor current detection means for detecting a motor current flowing in the assist motor;
Proportional-integral control means including at least one of a proportional element and an integral element based on a deviation between the target current and the motor current;
Motor drive means for driving the assist motor based on the output of the proportional-integral control means;
In an electric power steering apparatus comprising:
further,
A stop instruction signal detecting means for detecting a stop instruction signal of the assist motor;
Gain setting means for reducing the proportional gain and / or the integral gain with time when the stop instruction signal is detected;
Drive stopping means for stopping the driving of the assist motor when a predetermined time has elapsed after detecting the stop instruction signal;
An electric power steering apparatus comprising:   The drive stop means stops driving of the assist motor when a predetermined time has elapsed after detecting the stop instruction signal, or when the steering torque or the target current is a predetermined threshold value or less. The electric power steering apparatus according to 1. The stop instruction signal is an abnormality detection signal for detecting a plurality of abnormal states of the electric power steering device,
3. The electric power steering apparatus according to claim 1, wherein the proportional gain and / or the integral gain differs depending on each of the abnormal states. The stop instruction signal is an abnormality detection signal for detecting at least one abnormal state of the electric power steering device and an off signal of an ignition switch,
3. The electric power steering apparatus according to claim 1, wherein the proportional gain and / or the integral gain differs according to the abnormal state and the off signal. 4. The stop instruction signal is an abnormality detection signal for detecting a plurality of abnormal states of the electric power steering device,
The electric power steering apparatus according to claim 1 or 2, wherein the predetermined time varies depending on each of the abnormal states. The stop instruction signal is an abnormality detection signal for detecting at least one abnormal state of the electric power steering device and an off signal of an ignition switch,
The electric power steering apparatus according to claim 1, wherein the predetermined time varies depending on the abnormal state and the off signal.

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