JP2005319931A - Power steering control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power steering control device capable of securing safety without causing a decline in yield ratio. <P>SOLUTION: This power steering control device includes a motor 6 applying a steering assisting force to a steering system, a torque detecting means 3 detecting steering torque of the steering system, a correction value storing means 17 storing a correction value for correcting an error by the torque detecting means, a control torque generating means making correction to a torque value detected by the torque detecting means based on the correction value and generating control torque, a motor control means 15 controlling the motor corresponding to the control torque generated by the control torque generating means, a motor control restricting means 13 imposing restrictions on the motor control means based on the control torque, and a correction value abnormality detecting means detecting the abnormality of the correction value. The motor control restricting means 13 is configured to switch restriction characteristics depending on a case when the abnormality is detected by the correction value abnormality detecting means or a case when it is not detected. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes an electric power steering control device that reduces the steering force by causing the power of the motor to act on the steering as an auxiliary force, and in particular, includes a correction means for correcting an error in the torque signal and current detection, and further detects the torque signal and current detection. The present invention relates to an electric power steering control device that secures safety by limiting motor control based on values.

  In the conventional electric power steering, a motor is controlled based on a torque sensor that detects a steering torque, and an assisting force is generated in the steering system to reduce the steering force. For this reason, if there is an error in the torque sensor, it leads to deterioration of the steering feeling, which is not preferable. For this reason, torque correction means for correcting the error of the torque sensor is provided, and the correction value is stored in an EEPROM or the like, so that the deterioration of the steering feeling is eliminated. (For example, refer to Patent Document 1).

Japanese Patent No. 3159665

  In the conventional apparatus as shown in Patent Document 1, the torque detection error is reduced by providing the torque signal correcting means, and a good steering feeling is obtained. However, the error of the torque sensor varies from product to product, and in order to correct even a large error by the correcting means, it is necessary to set a wide correction range.

  However, if the correction range is set wide, if a correct correction value cannot be obtained due to an abnormality such as an EEPROM, the influence becomes large, which is not preferable for safety. For example, when the EEPROM cannot be read, if the power steering is controlled without correction, the control is performed based on the torque including an error. If the EEPROM cannot be read, there is a method in which the power steering control is stopped and the manual steering is performed.

  On the other hand, if the correction range is narrowed in consideration of safety, those having an error that cannot be corrected cannot be corrected and are dropped in the inspection process of the production line and do not flow out to the market. Therefore, even if the correction value cannot be read normally, even if it is used without correction, safety is easy to ensure because the error is originally small. However, the torque sensor having a large error cannot be corrected, and the yield deteriorates, which is not preferable in terms of productivity.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an electric power steering control device that ensures safety without causing a decrease in yield.

  An electric power steering control device according to the present invention includes a motor for adding a steering assist force to a steering system, torque detection means for detecting steering torque of the steering system, and a correction value for correcting an error of the torque detection means. Is generated by the control torque generation means, the control torque generation means for generating a control torque by correcting the torque value detected by the torque detection means based on the correction value. Motor control means for controlling the motor according to control torque, motor control restriction means for restricting the motor control means based on the control torque, and correction value abnormality detection means for detecting abnormality of the correction value. The motor control limiting means includes a case where the correction value abnormality detecting means detects an abnormality and a case where no abnormality is detected. It is obtained to switch the limitation characteristic in the.

  Since the electric power steering control device according to the present invention is configured as described above, when the correction value stored in the EEPROM or the like can be read normally, the original motor control characteristic and the motor control limit characteristic are used. The motor control characteristics and motor are set so that the optimum steering assist force can be generated and the optimum steering feeling can be obtained, and safety can be secured even if the correction value cannot be read normally. By using the control limiting characteristic, it is possible to obtain auxiliary force while ensuring safety. Further, since the safety can be ensured, the correction range can be widened. As a result, correction can be made even for a torque sensor or a current detection circuit having a large error, and the yield can be improved.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration of a general electric power steering. As shown in this figure, a steering wheel 1 coupled to a steering shaft 2, a torque sensor 3 coupled to the steering shaft 2 for detecting steering force, and coupled to the steering shaft 2, and a front wheel 9 of the vehicle. A steering system is constituted by the rack and pinion gear 8 coupled to the.

  The steering shaft 2 is coupled with a motor 6 for adding a steering assist force via a speed reducer 7. The motor 6 controls power steering based on a signal from the torque sensor 3 and a signal from the vehicle speed sensor 4. Driven by the ECU 5 to be performed, the output of the motor 6 is transmitted to the steering shaft 2.

Next, the internal configuration of the ECU 5 in the first embodiment will be described with reference to FIG.
In FIG. 2, the same parts as those in FIG. In FIG. 2, reference numeral 12 denotes a main microcomputer that outputs a motor control signal DRV for controlling the motor 6 based on a signal T1 from the torque sensor 3 and a signal SPD from the vehicle speed sensor 4, and reference numeral 13 denotes a drive by the main microcomputer 12. This is a motor control limiting circuit that outputs a motor drive permission signal PRM that permits power steering operation only when the motor 6 is driven in the permitted area, and prohibits power steering operation in the prohibited area. Yes.

  Reference numeral 14 denotes a motor control signal DRV output from the main microcomputer 12 to a motor drive circuit to be described later when the permission signal PRM from the motor control restriction circuit 13 is Hi. When the permission signal PRM is Low, the motor control signal DRV is transmitted. Is an AND circuit that shuts off the motor 6 and stops driving the motor 6. Reference numeral 15 is a motor drive circuit that drives the motor 6 based on a signal from the AND circuit 14, and reference numeral 16 is a current detection that detects the current that is being supplied to the motor 6. Reference numeral 17 denotes an EEPROM that stores a correction value of the torque sensor 3.

  Next, the operation of the main microcomputer 12 will be described using the flowchart shown in FIG. In step S101, the correction value ADJ1 is read from the EEPROM 17. In step S102, it is checked whether the read value is normal. The correction values are stored at two addresses in the EEPROM 17, and the correction values stored at the two locations are compared at the time of reading. If the result is normal, the determination flag (flag) is cleared in step S103, and the correction value ADJ1 read from the EEPROM 17 is substituted into the correction value ADJ2.

  On the other hand, if there is an abnormality in step S102, 1 is set in the determination flag (flag) in step S104, and zero is substituted for the correction value ADJ2. Next, in step S105, the determination flag (flag) and the correction value ADJ2 are transmitted to the sub-microcomputer 13. Thereafter, in step S106, the signal T1 from the torque sensor 3 is input, and in step S107, the torque signal T1 is corrected to calculate the control torque TRQ. Next, in step S108, the signal SPD from the vehicle speed sensor 4 is input, and in step S109, the target motor current Imt is determined based on the control torque TRQ obtained in step S107 and the vehicle speed SPD obtained in step S108.

In step S110, the signal Imd from the current detection circuit 16 is input. In step S111, a current F / B calculation is performed so that the target motor current Imt and the detection current Imd coincide.
Then, it returns to step S106 and repeats the process from step S106.
Next, processing from step S106 to step S109 will be described with reference to FIG. In FIG. 4, reference numeral 121 denotes a correction calculation for correcting the torque signal T1 according to the correction value ADJ2, which corresponds to step S107 in FIG.

  In this case, the torque sensor 3 has a characteristic T1 including an offset error as indicated by a broken line in FIG. 5, but by adding the correction value ADJ2 in the correction process 121, a characteristic TRQ indicated by a solid line without an offset error is obtained. It is done. Reference numeral 122 in FIG. 4 is a motor control characteristic that determines a target current based on the control torque TRQ and the vehicle speed SPD, and usually has the characteristic shown in FIG. The motor control characteristic 122 has the characteristics shown in FIG. 6 when the above-described determination flag (flag) = 0, but is switched to the characteristics shown in FIG. 7 when the determination flag (flag) = 1. ing.

Next, the operation of the current F / B calculation in step S111 will be described with reference to FIG.
FIG. 8 is a block diagram for performing general PI control. Here, the adder 123 calculates the deviation between the target motor current Imt and the detected current Imd, performs the proportional term calculation with the proportional term 124 on the result, performs the integral term calculation with the integral term 125, and adds the result to the adder. The motor control signal DRV is calculated by adding at 126. Although a detailed description of the motor control signal DRV is omitted, it is generally a PWM signal whose duty changes.

  Next, the operation of the motor control limiting circuit (sub-microcomputer) 13 will be described with reference to the flowchart shown in FIG. First, in step S201, a determination flag (flag) and a torque correction value ADJ2 are received from the main microcomputer 12, and then a torque signal T1 is input in step S202. Next, in step S203, a correction process is performed on the torque signal T1 to calculate a control torque TRQ.

  Thereafter, the motor current Imd is detected in step S204, and in step S205, it is determined from the control torque TRQ and the motor current detection value Imd whether or not it is in the motor drive permission region. The process branches to Yes in S206, and the motor drive permission signal PRM is cleared in Step S207. If the motor drive prohibition area is not entered in step S205, the process branches to No in step S206, and 1 is set in the motor drive permission signal PRM in step S208.

  Next, in step S209, the motor drive permission signal PRM is output, the process returns to step S202, and the processing from step S202 is repeated thereafter. Next, processing from step S202 to step S209 will be described with reference to FIG. In the figure, reference numeral 141 denotes a process of obtaining the control torque TRQ by correcting the torque signal T1 obtained from the torque sensor 3 using the torque correction value ADJ2 received from the main microcomputer 12, and corresponds to the process of step S203 in FIG.

Reference numeral 142 determines whether or not the motor drive prohibition region is based on the control torque TRQ and the motor current detection value Imd obtained from the current detection circuit 16 based on the motor drive restriction characteristic, and as a result, is in the motor drive prohibition region. In this case, the motor drive permission signal PRM is cleared. If the motor drive permission signal PRM is out of the motor drive inhibition area, the motor drive permission signal PRM is set to 1.
This corresponds to steps S205 to S209 in FIG.

  When the determination flag (flag) received from the main microcomputer 12 is 0, the motor drive restriction characteristic is selected as shown in FIG. 11, and when the determination flag (flag) is 1, the characteristic shown in FIG. It is configured. The determination flag (flag) is 0 when the torque correction value is normally read from the EEPROM, and is 1 when the torque correction value is not normally read. Therefore, the motor current limiting characteristic is when the torque correction value is normally read. If the characteristic shown in FIG. 11 cannot be read normally, the characteristic shown in FIG. 12 is obtained.

  Thus, in this embodiment, the motor control characteristic and the motor control limit characteristic are switched depending on whether or not the torque correction value ADJ1 has been normally read. When the torque correction value ADJ1 can be read normally, the motor control characteristic shown in FIG. 6 and the motor control limit characteristic shown in FIG. 11 are selected. FIG. 13 shows these two figures overlaid. If the torque correction value ADJ1 cannot be read normally, the motor control characteristic shown in FIG. 7 and the motor control limit characteristic shown in FIG. 12 are selected. FIG. 14 shows these two figures overlaid.

  When configured as in this embodiment, when the torque correction value can be read normally, an optimal steering feeling can be obtained by selecting an appropriately set motor control characteristic as shown in FIG. I can do it. Further, since the motor drive prohibition characteristic is also set optimally, safety can be ensured without impairing the steering feeling.

On the other hand, when the torque correction value cannot be read normally, the motor control characteristic and the motor control limit characteristic shown in FIG. 14 are selected. If the torque correction value cannot be read correctly, the torque correction value ADJ2 is set to zero in step S104 of FIG. 3, and as a result, control is performed without substantial correction. In FIG. 14, a dead zone ERR is provided for the motor control characteristics, and a drive inhibition region is set as wide as the ERR for the motor control limit characteristics.
The ERR is set in consideration of the maximum error of the torque sensor 3, and generates auxiliary force within a possible range while ensuring safety even without torque correction, and continues control of power steering.

  As described above, in this embodiment, when the torque correction value can be normally read, the optimum feeling is obtained by the optimally set control characteristics, and the torque adjustment value cannot be normally read. Even in this case, the power steering can be controlled as much as possible while ensuring safety. Even when the torque sensor error is large, safety can be ensured by optimally setting the ERR in FIG. Therefore, the correction range can be set wide to improve productivity.

  In this embodiment, the case where the offset error is corrected has been described. However, the same effect can be obtained even if the gain error is corrected.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 15 is a block diagram showing an internal configuration of ECU 5 in the second embodiment. In this figure, the same or corresponding parts as in FIG. The difference from FIG. 2 is that the EEPROM for storing the torque correction value is provided separately for the main CPU 17 and the sub CPU 20.

  Next, the operation of the main microcomputer 12 will be described using the flowchart shown in FIG. FIG. 16 is obtained by deleting the process of step S105 from FIG. 3 which is the flowchart of the first embodiment. The other steps are denoted by the same reference numerals as those in FIG.

  Next, the operation of the sub-microcomputer 13 will be described using the flowchart shown in FIG. FIG. 17 is obtained by changing step S201 from step S301 to step S304 with respect to FIG. 9 which is the flowchart of the first embodiment. Since other steps are not changed, the same reference numerals as those in FIG. In step S301, the torque correction value ADJ2 is read from the EEPROM 20 connected to the sub-microcomputer 13, and it is determined whether or not the torque correction value ADJ2 has been normally read. The determination as to whether or not the data has been read normally is the same as the processing of the main microcomputer 12 of the first embodiment.

  If the torque correction value ADJ2 can be read normally, the process branches to Yes in step S302, clears the determination flag (flag) in step S303, and substitutes the value ADJ2 read from the EEPROM in step S301 for the torque correction value ADJ2. If the torque correction value cannot be read normally, the process branches to No in step S302, the determination flag (flag) is set to 1 in step S304, and zero is substituted for the torque correction value ADJ2. Thereafter, the processing from step S202 is the same as that of the first embodiment shown in FIG.

  With the configuration as described above, even when the main microcomputer 12 and the sub-microcomputer 13 have correction values, the same effect as in the first embodiment can be obtained.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 18 is a block diagram showing an internal configuration of ECU 5 in the third embodiment. In this figure, the same or corresponding parts as in FIG. The difference from FIG. 2 is that a correction circuit 11 is added and a correction value ADJ2 transmitted from the main microcomputer 12 to the sub-microcomputer 13 is given to the correction circuit 11.

  The internal configuration of the correction circuit 11 is shown in FIG. In this figure, 11c is a memory for storing the torque correction value ADJ2 sent as a digital signal from the main microcomputer 12, and 11b is a D for converting the torque correction value ADJ2 stored in the memory 11c into an analog signal T_ADJ. The / A converter 11a is an adding circuit that adds the torque signal T1 obtained from the torque sensor 3 and the torque correction value T_ADJ obtained from the D / A converter 11b. As a result, the control torque TRQ can be obtained, and processing equivalent to the correction calculation 121 in FIG. 4 of the first embodiment is realized by hardware.

  Next, the operation of the main microcomputer 12 will be described using the flowchart shown in FIG. FIG. 20 is obtained by replacing step S105 with steps S401 and S402 and replacing steps S106 and S107 with step S403 with respect to FIG. 3 which is the flowchart of the first embodiment, and other steps are the same as FIG. . The same steps as those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted.

  In FIG. 20, the torque correction value is read from the EEPROM 17 in steps S101 to S104, and normality / abnormality of the read value is determined. Next, in step S401, the torque correction value ADJ2 determined in steps S101 to S104 is transmitted to the memory 11c. In step S402, a determination flag (flag) reflecting the result of normality / abnormality determination of the read value is reflected. Send to sub-microcomputer 13. In step S403, the control torque TRQ corrected by the correction circuit 11 is input. Thereafter, the processing from step S108 to S111 is the same as that in the first embodiment, and after the execution of step S111, the processing from step S403 is repeated.

Next, the operation of the sub-microcomputer 13 will be described using the flowchart shown in FIG. In step S501, a determination flag (flag) indicating whether or not the torque correction value has been normally read from the main microcomputer 12 is received. In step S502, the control torque TRQ corrected by the correction circuit 11 is input. Thereafter, the processing from step S204 to S209 is the same as that in the first embodiment, and after execution of step S209, the processing from step S502 is repeated.
With the configuration as described above, the same effects as those of the first embodiment can be obtained even when correction is performed by hardware.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 22 is a block diagram showing an internal configuration of ECU 5 in the fourth embodiment. In this figure, the same or corresponding parts as in FIG. The difference from FIG. 2 is that the output signal of the current detection circuit 16 is changed to Imd0, and the current correction value Kim2 is added to the data transmitted from the main microcomputer 12 to the sub-microcomputer 13.

  Next, the processing of the main microcomputer 12 will be described using the flowchart shown in FIG. In step S601, the torque correction value ADJ1 and the current correction value Kim1 are read from the EEPROM 17. In step S602, it is determined whether or not the data can be read normally by the same method as in the first embodiment. If the data can be read normally, the process branches to Yes. In step S603, the determination flag (flag) is cleared and the torque is corrected. The correction value ADJ1 read in step S601 is substituted for the value ADJ2, and the correction value Kim1 read in step S601 is substituted for the current correction value kim2. If the correction value cannot be read normally in step S602, the process branches to No, and in step S604, a determination flag (flag) is set, 0 is substituted for the torque correction value ADJ2, and 1 is substituted for the current correction value kim2.

Next, in step S605, the determination flag (flag), the torque correction value ADJ2, and the current correction value Kim2 are transmitted to the sub-microcomputer 13. Subsequent processing from step S106 to step S108 is the same as that in the first embodiment, and thus description thereof is omitted.
Next, in step S606, the target motor current Imt is determined according to the motor current characteristics based on the control torque TRQ obtained in step S107 and the vehicle speed SPD obtained in step S108.

  The motor current characteristic is configured to select the characteristic of FIG. 24 when the determination flag (flag) = 0, and to select the characteristic of FIG. 25 when the determination flag (flag) = 1. Next, in step S607, the signal Imd0 from the current detection circuit 16 is input, and in step S608, the calculation shown in FIG. 26 is performed to obtain the motor current Imd. FIG. 27 is a graph showing the calculation of FIG. Next, the current F / B control similar to that of the first embodiment is performed in step S111, and the processing from step S106 is repeated thereafter.

  Next, the processing of the sub-microcomputer 13 will be described using the flowchart shown in FIG. In step S701, a determination flag (flag), a torque correction value ADJ2, and a current correction value Kim2 are received from the main microcomputer 12. Next, a torque signal T1 is input in step S202, and torque correction processing is performed in step S203 to obtain a control torque TRQ. Steps S202 and S203 are the same as those in the first embodiment.

Next, in step S702, the signal Imd0 from the current detection circuit 16 is input, and in step S703, the calculation shown in FIG. 26 is performed to obtain the motor current Imd. Thereafter, in step S704, the control torque TRQ obtained in step S203 and the motor current Imd obtained in step S703 are compared with the motor control restriction characteristics to determine whether or not the drive inhibition region is entered.
The motor control limiting characteristic is configured to select the characteristic of FIG. 29 when the determination flag (flag) = 0, and to select the characteristic of FIG. 30 when the determination flag (flag) = 1.

The characteristics of this embodiment are summarized as follows.
(1) A correction process is performed on the detected current value.
(2) The motor control characteristic (FIG. 25) when the determination flag (flag) = 1 is set to be lower than the current value compared to FIG.
(3) When the current threshold value near the torque neutrality of the motor control limiting characteristic is the determination flag (flag) = 0 (FIG. 29), ILL1, and when the determination flag (flag) = 1 (FIG. 30) is ILL2. Different values are set such that ILL2 is lower than ILL1.

When current correction processing cannot be performed (when the determination flag = 1), appropriate correction cannot be performed, so there is a concern that the actual motor current may flow more than the target motor current Imt. The characteristics shown in FIGS. 25 and 30 are set in consideration.
With this configuration, safety can be ensured even when correction processing cannot be performed.

It is the schematic which shows the structure of a general electric power steering. FIG. 3 is a block diagram showing an internal configuration of an ECU in the first embodiment. 3 is a flowchart showing processing of the main microcomputer in the first embodiment. FIG. 3 is a control block diagram illustrating processing in the main microcomputer according to the first embodiment. 11 is a graph showing operations of the correction calculation 121 in FIG. 4 and the correction calculation 141 in FIG. 10. It is a figure which shows the motor control characteristic at the time of determination flag = 0 in Embodiment 1-3. It is a figure which shows the motor control characteristic at the time of determination flag = 1 in Embodiment 1-3. It is a block diagram which shows electric current F / B processing. 3 is a flowchart showing processing of a sub-microcomputer in the first embodiment. FIG. 3 is a control block diagram illustrating processing in the sub-microcomputer according to the first embodiment. 6 is a graph showing motor control restriction characteristics when determination flag = 0 in the first to third embodiments. 6 is a graph showing motor control restriction characteristics when determination flag = 1 in the first to third embodiments. 12 is a graph depicting FIG. 6 and FIG. 13 is a graph depicting FIG. 7 and FIG. FIG. 6 is a block diagram showing an internal configuration of an ECU in a second embodiment. 10 is a flowchart showing processing of the main microcomputer in the second embodiment. 10 is a flowchart showing processing of a sub-microcomputer in the second embodiment. FIG. 10 is a block diagram showing an internal configuration of an ECU in a third embodiment. FIG. 10 is a block diagram illustrating an internal configuration of a correction circuit according to a third embodiment. 10 is a flowchart showing processing of the main microcomputer in the third embodiment. 10 is a flowchart showing processing of a sub-microcomputer in Embodiment 3. FIG. 10 is a block diagram showing an internal configuration of an ECU in a fourth embodiment. 10 is a flowchart showing processing of a main microcomputer in the fourth embodiment. FIG. 10 is a diagram showing motor control characteristics when determination flag = 0 in the fourth embodiment. FIG. 10 is a diagram illustrating motor control characteristics when determination flag = 1 in the fourth embodiment. FIG. 10 is a block diagram illustrating a current correction process in the fourth embodiment. 10 is a graph showing a current correction process in the fourth embodiment. 10 is a flowchart showing processing of a sub-microcomputer in the fourth embodiment. 10 is a graph showing motor control restriction characteristics when determination flag = 0 in the fourth embodiment. 10 is a graph showing motor control restriction characteristics when determination flag = 1 in the fourth embodiment.

Explanation of symbols

1 steering wheel, 2 steering shaft, 3 torque sensor,
4 vehicle speed sensor, 5 ECU, 6 motor, 7 speed reducer,
8 rack and pinion gear, 9 front wheel, 11 correction circuit,
12 main microcomputer, 13 motor control limit circuit (sub microcomputer),
14 AND circuit, 15 motor drive circuit, 16 current detection circuit,
17, 20 EEPROM.

Claims (4)

A motor for adding a steering assist force to the steering system;
Torque detecting means for detecting steering torque of the steering system;
Correction value storage means for storing a correction value for correcting an error of the torque detection means;
Control torque generating means for generating a control torque by correcting the torque value detected by the torque detecting means based on the correction value;
Motor control means for controlling the motor according to the control torque generated by the control torque generation means;
Motor control limiting means for limiting the motor control means based on the control torque;
Correction value abnormality detecting means for detecting abnormality of the correction value,
The electric power steering control device characterized in that the motor control limiting means switches the limiting characteristics between when the correction value abnormality detecting means detects abnormality and when no abnormality is detected. A motor for adding a steering assist force to the steering system;
Torque detecting means for detecting steering torque of the steering system;
Motor current detection means for detecting the current of the motor;
Correction value storage means for storing a correction value for correcting an error of the motor current detection means;
Motor current value generating means for correcting the motor current detection signal detected by the motor current detecting means based on the correction value and generating a motor current value;
Motor control means for controlling the motor in accordance with the torque detected by the torque detection means;
Motor control limiting means for limiting the motor control means based on the torque and motor current value;
Correction value abnormality detecting means for detecting abnormality of the correction value,
The electric power steering control device characterized in that the motor control limiting means switches the limiting characteristics between when the correction value abnormality detecting means detects abnormality and when no abnormality is detected. A motor for adding a steering assist force to the steering system;
Torque detecting means for detecting steering torque of the steering system;
Correction value storage means for storing a correction value for correcting an error of the torque detection means;
Control torque generating means for generating a control torque by correcting the torque value detected by the torque detecting means based on the correction value;
Motor control means for controlling the motor based on motor control characteristics set in advance according to the control torque generated by the control torque generating means;
Correction value abnormality detecting means for detecting abnormality of the correction value,
The electric power steering control device characterized in that the motor control means switches the control characteristics of the motor between when the correction value abnormality detecting means detects an abnormality and when no abnormality is detected. A motor for adding a steering assist force to the steering system;
Torque detecting means for detecting steering torque of the steering system;
Motor current detection means for detecting the current of the motor;
Correction value storage means for storing a correction value for correcting an error of the motor current detection means;
Motor current value generating means for correcting the motor current detection signal detected by the motor current detecting means based on the correction value and generating a motor current value;
Motor control means for controlling the motor based on characteristics set in advance according to the torque detected by the torque detection means;
Correction value abnormality detecting means for detecting abnormality of the correction value,
The electric power steering control device characterized in that the motor control means switches the control characteristics of the motor between when the correction value abnormality detecting means detects an abnormality and when no abnormality is detected.

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