JP2008265422A - Electric power steering control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power steering control device, which easily and promptly checks the integrity or abnormality of data stored in a nonvolatile memory, at low cost. <P>SOLUTION: To control data stored in the nonvolatile memory 109, an identifying value for determining whether the control data matches a control program stored in an ROM114 is added in advance. When reading the control program and the control data, a CPU114 in the ECU 1 computes an identifying value on the basis of the control program and the control data, and compares the computed identifying value with the identifying value added to the control data in advance, thereby determining the consistency of the control program and the control data. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric power steering control device that applies a steering assist force to a steering device by a motor when a steering wheel steers a steering handle.

  An electric power steering device mounted on a vehicle such as an automobile assists a steering person by applying a steering assist force to the steering device by an output torque of a motor.

  A general schematic configuration of such an electric power steering apparatus is shown in FIG. As shown in FIG. 9, the electric power steering apparatus includes a torque sensor 83 that detects a steering torque of a shaft 82 that is directly connected to the steering handle 81, and a vehicle speed sensor that is attached to, for example, a vehicle wheel and detects the traveling speed of the vehicle. 84, an electric power steering control device (hereinafter also referred to as ECU) 85 that calculates a steering assist force based on detection signals of these sensors, and a motor that generates rotational torque based on a signal output from the ECU 85 86, a reduction gear 87 that transmits the generated rotational torque to the steering mechanism, a battery power supply 89 that supplies current to the ECU 85 by turning on the ignition key 88, and a universal joint that transmits the rotational movement of the steering handle 81 to the wheels. 90a, 90b, rack and pinion 91 and tie rod 92 It has been made.

FIG. 10 is a block diagram showing a general schematic configuration of the ECU 85. The ECU 85 includes a microprocessor (MCU) 851 including a CPU and a recording medium (for example, an internal memory such as a ROM and a RAM), a motor drive circuit 852, and a motor current detection circuit 853, and is stored in the internal memory of the MCU 851. A program and control data are read and executed by the CPU to drive the motor 86 based on the steering torque signal T detected by the torque sensor 83 and the vehicle speed signal V detected by the vehicle speed sensor 84. While generating the current control value E, the feedback control is performed so that the deviation between the current control value E and the motor current i detected by the motor current detection circuit 853 is reduced, thereby realizing the assist control.
The CPU executes a control program for these controls at a predetermined cycle based on a clock generation circuit (not shown). In addition, illustration of an interface or the like that converts signals such as the steering torque signal T and the vehicle speed signal V so that the MCU 851 can perform arithmetic processing is omitted.

  The application range of the electric power steering apparatus configured as described above has been extended to not only mini-passengers but also large vehicles such as ordinary vehicles and RVs in recent years. Large automobiles may have a large vehicle weight, and require a larger steering assist force, while further operability and safety are required. For this reason, the enhancement of the functionality of assist control (motor control) in the electric power steering control device has been remarkably progressed, and the capacity of control programs and control data stored in the internal memory of the MCU 851 has increased, and repeated versions thereof. Ups and updates are inevitable.

  In addition, due to market demands, it is required to respond to shortening of the development cycle in accordance with the model change of the electric power steering device, and accordingly, development of control programs and the like is inevitably shortened. Under such circumstances, the internal memory of the MCU 851 has a short preparation period, that is, the main role of the internal memory has shifted from ROM to Flash ROM. Furthermore, in order to further shorten the development period, control data has been stored in a nonvolatile memory (EEPROM) other than the MCU 851.

  In addition, the use of the EEPROM is preferable from the viewpoint of improving productivity because the control data can be updated and adjusted as appropriate even after the control program is stored (implemented) in the flash ROM. Furthermore, even when the electric power steering device is supplied to the market, for example, the control data can be updated at the vehicle dealer's destination, which can respond more quickly than the case where the flash ROM of the MCU 851 is rewritten and the cost can be reduced. It also has real benefits that can be made.

  As a technology related to the adoption of such a non-volatile memory, map data, engine specifications, and vehicle speed specifications are stored in advance in the non-volatile memory in order to share an ECU so as to absorb the difference in specifications of each vehicle type. When rewriting a non-volatile memory in which a control program is stored (for example, Patent Document 1), the information management center connected by the communication network rewrites while testing whether the rewriting data operates normally. Have been proposed (for example, Patent Document 2).

  On the other hand, since the data stored in the nonvolatile memory can be easily updated, various versions may exist. When the data is updated, the electric power steering control device stores the data in the flash ROM. There was a disagreement that the operator had to visually confirm the consistency between the control program and the control data updated and stored in the non-volatile memory sequentially with version information or the like.

Japanese Patent No. 3746030 JP 2000-43654 A

  Here, in contrast to the existence of such various versions, the example described in Patent Document 1 described above does not describe checking consistency in control data or the like. Further, in the example described in Patent Document 2 described above, since it is not a function of the ECU, there is a dislike of starting even if there is a mismatch between the control program and the control data when the ECU is started, and further via a network. Since the test is performed, the system becomes large-scale, which is not desirable from the viewpoint of cost and quick response.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to make it possible to easily and quickly confirm the consistency and abnormality of data stored in a nonvolatile memory at a low cost. A steering control device is provided.

  In order to achieve the above-described object, an electric power steering control device according to the present invention is configured as follows.

(1) Steering torque detection means for detecting steering torque generated in the steering handle and outputting a steering torque signal; a motor for applying steering assist force to the steering handle; and a control program for controlling the motor And an internal memory storing control data used when executing the control program, and reading the control program and the control data to execute the control program And an electric power steering control device for controlling the motor based on at least the steering torque signal,
The control data stored in the non-volatile memory is preliminarily added with an identification value for determining whether or not the control data is consistent with the control program, and the control program and the control data are When reading, an identification value calculating means for calculating an identification value based on these control program and control data;
A consistency determination unit that compares the identification value calculated by the identification calculation unit with the identification value added in advance to the control data, and determines the consistency between the control program and the control data;
An electric power steering control device comprising:
(2) The identification value calculation means includes:
The electric power steering control device according to (1), wherein the identification value is calculated based on internal data of the control data and version information added to the control program.
(3) The electric power steering control device according to (2), wherein the calculation of the identification value is performed based on a checksum method.
(4) The electric power steering control device according to (2), wherein the calculation of the identification value is performed based on a cyclic redundancy check method.
(5) The electric power steering control device according to any one of (1) to (4), wherein the consistency determination unit determines consistency when current is supplied.

According to the electric power steering control device described in (1) or (2) above, the control program compares the identification value calculated by the identification calculating means with the identification value added in advance to the control data. Therefore, the consistency and abnormality of the data stored in the nonvolatile memory can be easily and quickly confirmed at a low cost.
In addition, according to the electric power steering control device described in (3) above, the checksum value in the internal data of the control data and the version information of the control program is obtained by the checksum method, and this value is used as the identification value. Therefore, it is possible to reduce the time for consistency determination by suppressing the burden of calculation processing.
Further, according to the electric power steering control device described in the above (4), the CRC value in the internal data of the control data and the version information of the control program is obtained by the cyclic redundancy check (CRC) method. Since the value is used as the identification value, it is possible to perform the consistency determination with high accuracy.
According to the electric power steering control device described in (5) above, consistency is determined when the ECU is turned on, so that the steering wheel can grasp the abnormality before driving the vehicle, and safety It can be used for securing.

  According to the present invention, the consistency and abnormality of the data stored in the nonvolatile memory can be easily and quickly confirmed at low cost by determining when the ECU is turned on.

  Hereinafter, an embodiment of an electric power steering control device according to the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a hardware configuration of an electric power steering control device according to an embodiment of the present invention.

  In FIG. 1, an electric power steering control device (hereinafter also referred to as ECU) 1 includes a bus 100, a nonvolatile memory 109, an A / D converter 110, an interface (I / F) 111, a clock generation circuit 112, an MCU 200, and an RD. A converter 116, a PWM controller 117, a motor drive circuit 118, and motor current detection circuits 119 and 120 are provided. The MCU 200 includes a CPU 113, a ROM (internal memory) 114 (for example, a flash ROM), and a RAM 115.

  The bus 100 transmits and receives data among the A / D converter 110, the interface 111, the CPU 113, the ROM 114, the RAM 115, and the like.

  The A / D converter 110 includes a steering torque signal T output from the torque sensor 4, a current detection value output from the motor current detection circuits 119 and 120, a motor rotation angle signal output from the RD converter 116, and the motor 3. Converts the voltage between terminals into a digital signal.

  The interface 111 counts the vehicle speed signal (pulse signal) V output from the vehicle speed sensor 2, converts it to a digital signal, and outputs it to the bus 100.

  A ROM 114 connected to the bus 100 is a control program such as a control program for controlling the motor 3 to realize assist control, a calculation program for the PWM controller 117, a compensation program for the output torque (steering assisting force) of the motor 3, which will be described later. The RAM 115 is used as a work memory for operating these control programs. As shown in FIG. 2, the control program stored in the ROM 114 is ver. Data data is added to the header portion of the program code, for example.

In addition, the nonvolatile memory 109 is configured by an EEPROM, and can hold the contents stored in the memory even after the ignition key is turned off. It is also used to record and hold control data such as vehicle speed sensitivity map data, which will be described later, and control parameters for assist control (motor control). These control data can be rewritten from the outside using a dedicated rewriting tool. As shown in FIG. 3, the control data stored in the nonvolatile memory 109 includes the control data separately from internal data (for example, vehicle speed response map data, control parameters, etc.) for execution of the control program. An identification value (check_data) for confirming the consistency as to whether or not the control data corresponds to the program is added in advance to the header portion of the data code, for example.
Note that check_data is data defined in advance as an eigenvalue based on a combination of the control data and the control program. For example, check_data is obtained from the contents of the control data and the Ver. It is a value that is calculated in a genuine and unique manner from data.

  The PWM controller 117 performs pulse width modulation on the signal representing the torque of the motor 3 and converts it into duty command value pulse signals W, V, U, Wb, Vb, Ub. Here, the pulse signals W, V, and U represent positive-phase three-phase signals, and the pulse signals Wb, Vb, and Ub represent negative-phase three-phase signals.

The motor drive circuit 118 is composed of three inverter circuits for generating currents of W, U, and V phases that drive the motor 3. Each of these inverter circuits is composed of two switching transistors cascaded between a power supply voltage and a ground potential, and positive phase duty command value pulse signals W, V, U are inputted to the gates of the upper switching transistors. The lower-stage switching transistors receive opposite-phase duty command value pulse signals Wb, Vb, Ub. As a result, the upper and lower switching transistors perform complementary operations, and alternately turn on and off to generate drive currents IU, IV, and IW of the motor 3 having a desired pulse width.
In order to prevent the switching transistors at the upper and lower stages from being turned on at the same time, both before and after the on-time of W, V, U and Wb, Vb, Ub of the duty command value pulse signals of the normal phase and the reverse phase. A time (dead time) in which both switching transistors are turned off is provided. Thereby, it is possible to avoid a short circuit between two switching transistors connected in cascade.

  The RD converter 116 supplies an excitation current to the resolver 5 and outputs an output signal from the resolver 5 to the A / D converter 110 as a rotation angle signal.

  The motor current detection circuits 119 and 120 are configured by current-voltage conversion elements such as resistors, detect the drive currents IU and IW of the motor 3, and output current detection values of voltages corresponding to the currents. The detected current value is corrected for voltage fluctuation by a power supply voltage correction circuit (not shown), amplified by the amplifier circuits 121 and 122, and then converted into a digital signal by the A / D converter 110.

  FIG. 4 is a block diagram showing a control function for performing assist control of the CPU 113 constituting the ECU 1, that is, a control program executed by the CPU 113 is shown for each block. The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is simplified or omitted. Further, control data having internal data such as vehicle speed response map data and control parameters is read for each block, for example, when the control program is executed, and assist control is performed.

  As shown in FIG. 4, the ECU 1 includes a torque system that performs control using a steering torque signal T, a current control system that performs control related to driving of the motor, and an output torque (steering assist command value) of the motor 3. It is comprised from the compensation system etc. which correct | amend. The torque system includes a steering assist command value calculation unit 10, a differential controller 30, and the like, and the current control system includes a subtractor 97, a current controller 98, a PWM controller 117, a motor drive circuit 118, a motor current detector 119, The compensation system is composed of a phase compensator 20, a convergence controller 60, an inertia compensator 70, and a SAT estimation compensator 80.

  The steering torque signal T is detected by the torque sensor 4 and input to the steering assist command value calculation unit 10, the differentiation controller 30, and the SAT estimation compensation unit 80.

  The steering assist command value calculation unit 10 calculates a steering assist command value I to be supplied to the motor based on the steering torque signal T and the vehicle speed signal V, and outputs the steering assist command value I to the phase compensator 20. The steering torque is greatest when the vehicle is stopped. On the other hand, there is a characteristic that the steering torque decreases as the vehicle speed increases. Therefore, the steering assist command value calculator 10 has a vehicle speed sensitivity map in which this characteristic is shown in advance. According to the data, the relationship between the steering torque signal T and the steering assist command value I supplied to the motor 3 is changed according to the vehicle speed signal V, thereby improving the steering feeling and stabilizing the vehicle behavior. .

Phase compensator 20 performs phase compensation on the steering assist command value I, and outputs a steering assist command value I _P which phase compensation is applied to the subtracter 95 and the estimated SAT compensator 80. The phase compensator 20 removes the peak value at the resonance frequency of the resonance system composed of the inertia element and the spring element included in the output torque from the motor 3, and the phase of the resonance frequency hinders the responsiveness and stability of the control system. To compensate for the deviation, improve the transient characteristics or stabilize the control system.

  The differential controller 30 takes in the steering torque signal T, corrects the steering assist command value I according to the fluctuation of the steering torque signal T, and suppresses the fluctuation of the output torque by the motor 3 to control near the neutral point of the steering. Responsiveness is improved, and smooth and smooth steering is realized. Then, the output result of the differentiation controller 30 is output to the subtracter 95.

  On the other hand, the motor angular velocity estimation unit 40 estimates the motor angular velocity ω based on the output signal of the resolver 5. The motor angular velocity ω is input to the convergence controller 60, the motor angular acceleration estimator 50, and the SAT estimation compensator 80, respectively. Further, the motor angular acceleration estimation unit 50 performs a differentiation process on the motor angular velocity ω to estimate the motor angular acceleration α and outputs it to the inertia compensator 70 and the SAT estimation compensator 80.

  The convergence controller 60 receives the motor angular velocity ω as an input and corrects the steering assist command value I in a direction that prevents the steering handle from rotating in order to improve the convergence of the vehicle, and the steering handle swings around. The brake is applied to the operation, and the behavior of the steering handle after the steering is stabilized.

  Then, the inertia compensator 70 receives the motor angular acceleration α as an input, and corrects the steering assist command value I according to the change in the inertia system related to the drive system such as the steering handle, the rack and pinion, the motor 3 and the reduction gear. Thus, fluctuations in output torque are suppressed. Thus, the inertia of the drive system is prevented from being transmitted to the steering person, and the steering feeling is improved.

The SAT estimation compensator 80 receives the steering torque signal T, the steering assist command value _IP , the motor angular acceleration α, and the motor angular velocity ω, and corrects the steering assist command value I in a direction that assists the operation of the steering handle. To improve the return of the steering wheel after steering.

Here, the SAT estimation compensator 80 will be described in more detail with reference to FIG.
A steering torque Th is generated when the steering wheel steers the steering handle, and the motor 3 generates an auxiliary torque (output torque) Tm according to the steering torque Th (corresponding to the steering torque signal T). As a result, the wheels are steered and SAT is generated as a reaction force. Further, at that time, torque serving as steering steering resistance is generated by the inertia J and friction (static friction) Fr of the motor 3. Considering the balance of these forces, the following equation of motion can be obtained:

J · α (s) + Fr · sign (ω) + SAT = Tm + Th (1)
Here, when the above equation (1) is Laplace transformed with an initial value of zero and solved for SAT, the following equation (2) is obtained.

      SAT (s) = Tm (s) + Th (s) −J · α (s) −Fr · sign (ω (s)) (2)

The auxiliary torque Tm is because it is possible to estimate the steering assist command value I _P, SAT estimation compensator 80 according to the above (2) can correct the steering assist command value I to estimate the SAT.

Returning again to FIG. 4, the description will be continued.
The adder 93 adds the output of the inertia compensator 70 and the output of the SAT estimation compensator 80 and outputs the addition result to the adder 94. Then, the adder 94 adds the output of the adder 93 and the output of the convergence controller 60, and outputs the addition result to the subtracter 95.

Subtractor 95, the output of the differential controller 30 and the steering assist command value I _P and addition processing, and the output of the adder 94 from the addition result to subtraction processing, the result as the torque command value 2 It outputs to the current command value calculation part 96 comprised with a three-phase converter etc.

Next, the subtractor 97 subtracts the outputs of the current detectors 119 and 120 from the current command value calculated by the current command value calculation unit 96 and outputs the result to the current controller 98. The current controller 98 takes in the output signal of the subtractor 97 and calculates a voltage command value based on the output signal. Further, the duty ratio is calculated from the voltage command value by the PWM controller 117, the inverter circuit is driven by the motor drive circuit 118, and the voltage is applied to the motor 3.
As a result, a steering assist force is applied to the steering mechanism by the output torque of the motor 3 to assist the steering of the steering person.

  Next, an operation flow for checking the consistency between the control program and the control data when the ECU 1 is started (when the power is turned on) will be described with reference to FIG. Note that this operation flow is executed by the CPU 113, that is, the CPU 113 also has a function of determining the consistency between the control program and the control data (consistency determining means).

  When the ECU 1 is started (ie, S601), the Ver. The CPU 113 reads data (ie, S602) and the control data (ie, S603) via the RAM 115. Then, the CPU 113 reads the Ver. Based on the internal data of data and control data, an identification value calculation process is performed to calculate an identification value (ie, S604). Thereafter, the identification value and check_data stored in the non-volatile memory are compared and determined (ie, S605). If they match, there is no abnormality (match) (ie, S606), and if they do not match, there is an error (mismatch). (I.e., S607).

  After the consistency determination, the ECU 1 notifies the steering operator of the abnormality without starting the assist control and ends the control (that is, S608). Alternatively, for example, standard control data may be mounted in a separate system in the ROM 114 in advance, and after the abnormality determination, the control data may be read to perform the assist control instead.

  Next, with reference to FIG. 7, the operation flow for the identification value calculation (a subroutine for the identification calculation process) will be described in more detail. This operation flow is executed by the CPU 113, that is, the CPU 113 has a function (identification value calculation means) for reading the control program and control data and calculating the identification value.

  In the identification value calculation process of the present embodiment, a variable SUM is prepared as a variable. When the identification calculation process is performed, the variable SUM is initialized (“0” is substituted) (that is, S701). . After this initialization, the internal data of the control data is sequentially added to the variable SUM until the end of the internal data of the control data read sequentially is read (that is, NO in S702, S703, and S703). . That is, all the internal data in the control data is added. After the internal data is added to the end (that is, YES in S703), Ver. Is added to the variable SUM that is the result of adding all the internal data. Data is added (ie, S704), and the value is returned as the identification value (ie, S705). Match / mismatch is determined by this identification value (checksum method).

  As a result of the consistency determination based on the identification value, the cause of the abnormality is (1) the version of the control data and the control program is inconsistent. It is assumed that the values (values of the variable SUM) do not match, (3) check_data is not correctly calculated by a regular tool, and the like. In addition, since there are many cases of said (1) as a frequent appearance degree, when determining abnormality, it will test | inspect from the item of (1).

  According to the present embodiment, the identification value calculated based on the control program and the control data is compared with the identification value added to the control data stored in the nonvolatile memory 109, and the control is performed. The consistency between the program and the control data is determined. Therefore, the consistency and abnormality of the control data stored in the nonvolatile memory 109 can be easily and quickly confirmed at a low cost.

  Furthermore, according to the present embodiment, since the process is performed by repeating the addition process of the control data stored in the nonvolatile memory 109 (checksum method), the control program and the control are performed without increasing the calculation amount of the CPU 113. The consistency with the data can be confirmed.

  In addition, since the consistency is determined when the ECU 1 is started, the steering wheel can grasp the abnormality before driving the vehicle, which leads to ensuring safety.

  In the conventional technique (for example, Patent Document 2 described above), since the test is performed using the rewriting tool, the version of the control data and the control program may be inconsistent, or the check_data calculation error may be overlooked by a legitimate tool. However, according to the present invention, it is possible to easily and quickly detect the inconsistency and the operation error at a low cost.

Here, as another embodiment, another operation flow when a CRC (Cyclic Redundant Check) method is applied to the identification value calculation will be described with reference to FIG. In the figure, the CRC-CCITT system is shown, and GP (X) = X ¹⁶ + X ¹² + X ⁵ +1 is adopted as a generating polynomial. However, the present invention is not limited to this, and the arithmetic processing capability of the CPU 113 and the ROM 114 If there is a margin in capacity, the identification value may be calculated using a hash function such as MD4 (Message Digest Algorithm 5) or SHA (Secure Hash Algorithm) instead of this method. Similarly, this operation flow is executed by the CPU 113.

  As shown in FIG. 8, in this embodiment, internal data of the control data and Ver. The value obtained by adding data is divided by the generator polynomial, the remainder is calculated as a CRC value, the CRC value is returned as an identification value, and identification value calculation processing is performed.

  That is, the variable GP that indicates the generator polynomial GP (X), the internal data of the control data, and the Ver. In order to sequentially read data data from the head, a pointer P and a variable CRC used as an identification value are first prepared. When an identification calculation process is performed, “0x0810” is assigned to the variable GP as an initial value. (That is, S801).

  Next, after the pointer P is set to the start of the internal data of the control data, that is, the start address of the internal data expanded in the memory area, the variable CRC is initialized (“0” is substituted) (ie, S803). ). Thereafter, it is determined whether or not the most significant bit of the variable CRC is “1” (ie, S804). If the most significant bit is “1”, the exclusive OR of the variable CRC and the variable GP is taken, a 1-bit shift is performed, and the exclusive OR of the pointer P and “1” is calculated. Thereafter, the result of the bit shift and the exclusive OR of the pointer P and “1” are added, and the result is substituted into the variable CRC to update the variable CRC (ie, S805). On the other hand, if the most significant bit is not “1”, the variable CRC is shifted by 1 bit, the result of this bit shift and the pointer P are added, and the result is assigned to the variable CRC and the variable. The CRC is updated (ie, S806).

  After the processing of S805 or S806, the pointer P is set to the next address, and it is determined whether or not the set address is at the end of the internal data (that is, S807). If it is determined that the data is not at the end (that is, NO in S807), the process returns to S804 again. That is, the steps S804 to S806 are sequentially repeated until the end of the internal data of the control data, and the variable CRC is substituted and updated.

  Thereafter (that is, YES in S807), the pointer P is set to Ver. The process is reset (ie, S809 to S812) in the same manner as the process for the internal data of the control data (ie, S802 to S807). Then, the value of the variable CRC obtained by a series of processes is returned as an identification value.

  In this way, the data set in the pointer P and the logical operation / bit shift are executed, so that the internal data of the control data and the Ver. A CRC value combined with data can be obtained. For this reason, by returning this value as the identification value, it is possible to cope with, for example, a case where bit corruption occurs at the same position of both data, and the identification value can be calculated with high accuracy.

  This is the end of the description of specific embodiments. However, aspects of the present invention are not limited to these embodiments, and modifications, improvements, and the like can be made as appropriate.

  The present invention is applicable to all electric power steering devices regardless of the type of electric power steering device (column type, pinion type, rack type) and the type of motor (with brush, brushless, etc.).

It is a block diagram which shows the hardware constitutions of the electric power steering control apparatus which concerns on this invention. It is a conceptual diagram for demonstrating the structure of the control program stored in ROM of the electric power steering control apparatus which concerns on this invention. It is a conceptual diagram for demonstrating the structure of the control data stored in the non-volatile memory of the electric power steering control apparatus which concerns on this invention. It is a block diagram which shows the function of CPU which comprises ECU of the electric power steering control apparatus which concerns on this invention. It is a schematic diagram which shows the mode of the torque generate | occur | produced between a road surface and steering. It is a figure which shows the operation | movement flow for confirming the consistency with the control program which concerns on this invention, and control data. It is a figure which shows the operation | movement flow of the subroutine for calculating the identification value shown in FIG. It is a figure which shows the operation | movement flow of another subroutine for calculating the identification value shown in FIG. It is a figure which shows schematic structure of a general electric power steering apparatus. It is a block diagram which shows schematic structure of ECU.

Explanation of symbols

1 ECU (electric power steering controller)
2 Torque sensor (steering torque detection means)
DESCRIPTION OF SYMBOLS 3 Motor 10 Steering assistance command value calculating part 20 Phase compensator 60 Convergence controller 70 Inertial compensator 80 SAT estimation compensator 109 Non-volatile memory 113 CPU (identification value calculating means, consistency determining means)
114 ROM (internal memory)

Claims (5)

A steering torque detecting means for detecting a steering torque generated in the steering handle and outputting a steering torque signal, a motor for applying a steering assist force to the steering handle, and a control program for controlling the motor are stored. An internal memory and a non-volatile memory storing control data used when executing the control program, and reading the control program and the control data to execute the control program, An electric power steering control device for controlling the motor based on the steering torque signal,
The control data stored in the non-volatile memory is preliminarily added with an identification value for determining whether or not the control data matches the control program, and the control program and the control data are When reading, an identification value calculating means for calculating an identification value based on these control program and control data,
A consistency determination unit that compares the identification value calculated by the identification calculation unit with the identification value added in advance to the control data to determine the consistency between the control program and the control data;
An electric power steering control device comprising: The identification value calculating means includes
The electric power steering control device according to claim 1, wherein the identification value is calculated based on internal data of the control data and version information added to the control program.   The electric power steering control device according to claim 2, wherein the calculation of the identification value is performed based on a checksum method.   The electric power steering control device according to claim 2, wherein the calculation of the identification value is performed based on a cyclic redundancy check method.   The electric power steering control device according to any one of claims 1 to 4, wherein the consistency determination unit determines consistency when current is supplied.

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