JP6151107B2 - Failure detection device - Google Patents

Description

  The present invention relates to a failure detection device that detects a failure of a hall sensor.

  A technique is known in which the position (electrical angle) of a rotor of a motor is detected by a detector such as a hall sensor and the motor is controlled according to the detection result. In particular, a high resolution sensor such as a resolver is used to control a motor used in an electric power steering, an electric brake system, or the like in order to reduce torque fluctuation.

  For example, in Patent Document 1, maximum amplitude values of a sine wave signal and a cosine wave signal input from a resolver that is a detector are calculated for each electrical angle period, and a comparison result between each maximum amplitude value and a threshold amplitude. Describes a failure detection device for detecting resolver failures based on the above.

JP 2011-89935 A

  Although the resolver (detector) has a feature of relatively high resolution, it costs more than the case of using a hall sensor, and the control circuit for processing the signal from the resolver becomes complicated. There is.

  Further, in the technique described in Patent Document 1, when the number of samples per cycle of the sine wave signal and the cosine wave signal is small, even if the resolver failure can be determined, the process is deferred and the number of samples is gradually increased. Increase it. Therefore, even when the resolver fails, it takes a predetermined time to output the determination result, and there is a possibility that the resolver failure cannot be detected early.

  In addition, when using a relatively inexpensive Hall sensor as an electrical angle detector and determining that there is a failure only when the digital signals from the Hall sensor are all high or all low, the following problems arise: . That is, in this case, since all the hall sensors are detected as having failed at the time of failure, there is a problem that it takes too much time to detect the failure.

  Then, this invention makes it a subject to provide the failure detection apparatus which can detect the failure of a Hall sensor appropriately.

As a means for solving the above-described problem, the failure detection apparatus according to the present invention receives a digital signal corresponding to a change in magnetic flux accompanying driving of the motor from a plurality of hall sensors installed in the motor. And at least one of the plurality of Hall sensors based on the electrical angle calculated by the electrical angle calculation means, and an electrical angle calculation means for calculating the electrical angle of the motor corresponding to each combination of digital signals. A failure determination means for determining whether or not a failure has occurred; an electrical angle change amount calculated by the electrical angle calculation means; and an electrical angle change amount calculation means for outputting to the failure determination means; The electrical angle calculation means includes a first predetermined value that is less than 0 ° or greater than 360 ° as the electrical angle of the motor when the combinations are all high or all low. Output to the failure determining means, the failure determining means, wherein the first predetermined value from the electrical angle calculation means is input at least once, and from the electric angle change amount calculation means, the absolute value of a plurality of the It is determined that at least one of the plurality of Hall sensors has failed when a change amount equal to or greater than a second predetermined value larger than the electrical angle resolution of the Hall sensor is input at least once .

According to such a configuration, when the combination of the digital signals input from the hall sensors is all high or all low, the electrical angle calculation means outputs the first predetermined value as the electrical angle of the motor.
For example, if at least one of a plurality of hall sensors fails and a high digital signal is constantly output, the state in which the output values of the hall sensors that change from moment to moment all become high is one of the electrical angles. Occurs at least once in a cycle.

Here, when all combinations of High / Low representing the electrical angle are High, the first predetermined value output from the electrical angle calculation means is set as a value less than 0 ° or greater than 360 °. That is, the first predetermined value is set as a value that is not output as an electrical angle when all of the plurality of Hall sensors are normal (the electrical angle is 0 ° or more and 360 ° or less).
Therefore, the failure determination means can clearly distinguish between a state in which all the hall sensors are normal and a state in which at least one hall sensor has failed, and the failure of the hall sensor can be detected appropriately.

Further, the failure determination means receives the first predetermined value from the electrical angle calculation means at least once, and the change amount whose absolute value is greater than or equal to the second predetermined value from the electrical angle change amount calculation means at least once. If it is determined that at least one hall sensor has failed.
Here, the second predetermined value is set as a value that is larger than the electrical angle resolution of the plurality of Hall sensors (that is, a value that is not output as a change amount of the electrical angle calculated every predetermined time). Thus, since the failure of the Hall sensor is detected based on the electrical angle of the motor and the amount of change in the electrical angle, a highly reliable failure detection device can be provided.

  The first predetermined value is preferably set in advance as an angle (60 ° × n) of less than 0 ° or greater than 360 °. Here, n is an integer excluding 0-6.

  According to such a configuration, (60 ° × n) is preset as the first predetermined value (where n is an integer other than 0 to 6). For example, when all combinations of digital signals input from the hall sensors are High, the electrical angle calculation means outputs the electrical angle (60 ° × n) as the first predetermined value to the failure determination means. As a result, it is possible to appropriately detect a failure of the Hall sensor without causing a problem in the control of the motor.

  Moreover, it is preferable that the failure determination means determines whether at least one of the plurality of hall sensors installed in the motor that rotates forward or backward according to an operation by a driver has failed.

  According to such a configuration, it is possible to appropriately detect a failure of a plurality of hall sensors installed in a motor that rotates forward or reversely according to an operation by a driver.

  ADVANTAGE OF THE INVENTION According to this invention, the failure detection apparatus which can detect the failure of a Hall sensor appropriately can be provided.

It is a schematic structure figure containing a failure detection device concerning one embodiment of the present invention. It is a block diagram of the control apparatus containing a failure detection apparatus. (A) is a waveform diagram of the output voltage of the Hall sensor at the normal time, (b) is the actual electrical angle at the normal time, the digital signal output from each Hall sensor, and the output value θ _{e of the} electrical angle calculation unit (C) is an explanatory diagram when the digital signals output from the Hall sensor are all high or all low. It is a flowchart which shows the flow of the process which a control apparatus performs. (A) is explanatory drawing when one Hall sensor becomes high sticking failure, (b) is explanatory drawing when one Hall sensor becomes low sticking failure. (A) is explanatory drawing in case two Hall sensors become high sticking failure, (b) is explanatory drawing in case two Hall sensors become low sticking failure. (A) is explanatory drawing when all Hall sensors become high sticking failure, (b) is explanatory drawing when all Hall sensors become low sticking failure.

  Modes for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings as appropriate. Hereinafter, a case where all of the three hall sensors Hu, Hv, and Hw are normal is referred to as “normal”. On the other hand, a case where at least one of the three hall sensors Hu, Hv, and Hw has failed is referred to as “at the time of failure”.

<Embodiment>
Prior to the failure detection apparatus 110 according to the present embodiment, the inverter 300, the motor 400, and the hall sensors Hu, Hv, and Hw will be described.
Inverter 300 shown in FIG. 1 is a power converter that converts DC voltage _VDC input from DC power supply 200 into a three-phase AC voltage and outputs the same to motor 400. The DC power supply 200 has a smoothing capacitor C connected in parallel to the inverter 300.

The inverter 300 converts the DC voltage _VDC into a three-phase AC voltage by switching ON / OFF of the switching elements S1 to S6 in accordance with a PWM (Pulse Width Modulation) signal input from the control device 100. Note that the switching elements S1 to S6 are connected in reverse parallel with free-wheeling diodes D1 to D6 for preventing breakage due to commutation.

The motor 400 is a three-phase brushless motor, for example, and is connected to the inverter 300 via three-phase windings u, v, and w. The motor 400 includes a stator 410 around which three-phase windings u, v, and w are wound, and a rotor 420 that is accommodated in the stator 410. The three-phase windings u, v, and w wound around the stator 410 are arranged at 120 ° intervals in the circumferential direction.
Note that the arrangement of the three-phase windings u, v, and w may be changed as appropriate according to the number of poles of the motor 400.

The rotation axis k of the motor 400 is connected to a load (not shown). The above-described load is, for example, a gear mechanism (not shown) that converts the rotation of the motor 400 into a reciprocating motion of a piston. This gear mechanism is connected to a piston (not shown) that reciprocates in a cylinder (not shown) in accordance with forward / reverse rotation of the motor 400.
When the motor 400 is driven in accordance with the brake operation by the driver, the rotor 420 rotates forward or backward. As a result, the piston slides in a cylinder (not shown), and brake fluid pressure can be generated.

Each of the hall sensors Hu, Hv, Hw shown in FIG. 1 has a function of outputting a digital signal (High / Low) corresponding to the electrical angle of the motor 400 to the control device 100. Hall sensors Hu, Hv, and Hw are installed in the motor 400 at 120 ° intervals in the circumferential direction so as to correspond to the three-phase windings u, v, and w.
The Hall sensors Hu, Hv, and Hw are packaged with a Hall element (not shown) and a Hall IC (Integrated Circuit: not shown) that converts an analog signal input from the Hall element into a digital signal. It has a configuration.

  The Hall element (not shown) detects magnetic fluctuations that occur when the motor 400 is driven, and outputs a sinusoidal analog signal corresponding to its installation position and the electrical angle of the motor 400 to the Hall IC ( (Not shown). The Hall IC compares an analog signal input from the Hall element with a predetermined threshold value, converts the analog signal into a digital signal, and outputs the digital signal to the control device 100 (failure detection device 110).

  As shown in FIG. 3A, in the normal state, the Hall sensor Hu outputs an ON signal (High) to the control device 100 at an electrical angle of 0 ° to 30 ° and 210 ° to 270 °, and an electrical angle of 30 ° to 30 °. Outputs an OFF signal (Low) at 210 °. As described above, since the Hall sensors Hu, Hv, and Hw are arranged at 120 ° intervals in the circumferential direction, the voltages V (Hu), V (Hv), and V (Hw) shown in FIG. The phase is shifted by 120 °.

3 (b) shows the actual electrical angle at the time of normal, the Hall sensors Hu, Hv, the digital signal output from the Hw, and the relationship between the output value theta _e of the electrical angle calculation unit 111 (see FIG. 2) It is explanatory drawing.
Note that the electrical angles 0 °, 60 °,... Shown in FIG. 3B representatively represent the median values of the electrical angles 330 ° -30 °, 30 ° -90 °,. It is a thing. Further, “H” shown in FIG. 3B means a high digital signal, and “L” means a low digital signal.

  As shown in FIG. 3B, the hall sensors Hu, Hv, and Hw output a digital signal having an electrical angle resolution of 60 ° to the control device 100 in accordance with the electrical angle of the motor 400 that changes every moment. ing. The explanatory diagram of FIG. 3C will be described later.

<Configuration of failure detection device>
The control device 100 shown in FIG. 2 includes electronic circuits such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various interfaces, and is configured according to programs stored therein. Demonstrate the function.

The failure detection device 110 is a device that detects a failure of the Hall sensors Hu, Hv, Hw installed in the motor 400 and is included in the control device 100.
The failure detection apparatus 110 includes an electrical angle calculation unit 111, a storage unit 112, a first determination unit 113, an electrical angle change amount calculation unit 114, a second determination unit 115, and an integrated processing unit 116. ing.

A digital signal corresponding to a change in magnetic flux accompanying driving of the motor 400 is input from the hall sensors Hu, Hv, Hw to the electrical angle calculation unit 111 (electrical angle calculation means). Then, the electrical angle calculation unit 111 calculates the electrical angle of the motor 400 corresponding to each combination of digital signals.
As shown in FIG. 3B, for example, when the digital signals corresponding to the Hall sensors Hu, Hv, and Hw are (L, H, L), the electrical angle calculation unit 111 outputs the electrical angle output value θ _e. As a result, 60 ° is calculated. Note that the cycle in which the processing is executed is set in advance so that the electrical angle computing unit 111 performs the computation processing with an electrical angle resolution of 60 °.

The electrical angle calculating section 111, the Hall sensor Hu, Hv, a digital signal corresponding to Hw is (H, H, H) or (L, L, L) if it is, as an output value theta _e of the electrical angle " −360 ° ”(first predetermined value) is set (see FIG. 3C).

The electrical angle calculation unit 111 outputs the calculated electrical angle output value θ _e to the motor control unit 120, the first determination unit 113, and the electrical angle change amount calculation unit 114, and temporarily stores the output value θe in the storage unit 112. . Motor control unit 120 described above, in accordance with the output value theta _e inputted from the electrical angle calculation unit 111, controls the driving of the motor 400 based on the PWM control.

The first determination unit 113 (failure determination means), the output value theta _e inputted is determined whether the previously described "-360 °" from the electrical angle calculation unit 111, the determination result to the integration processing unit 116 Output. That is, when the output value θ _e ≠ −360 ° (that is, electrical angle 0 ° to 360 °), the first determination unit 113 outputs the flag signal F1: OFF to the integration processing unit 116. On the other hand, when the output value θ _{e is} −360 °, the first determination unit 113 outputs the flag signal F1: ON to the integration processing unit 116.
The output value θ _e = −360 ° corresponds to the case where the digital signal is (H, H, H) or (L, L, L) (see FIG. 3B).

The electrical angle change amount calculation unit 114 (electric angle change amount calculation means) has a function of calculating the change amount of the electrical angle that changes every moment at predetermined time intervals. That is, the electrical angle change amount calculation unit 114 calculates the difference between the current output value θ _e (electrical angle) calculated by the electrical angle calculation unit 111 and the previous output value (electrical angle) read from the storage unit 112. The difference is calculated, and the difference is output to the second determination unit 115 as the electrical angle change amount Δθ.
The calculation cycle of the electrical angle change amount calculation unit 114 is set in advance so that at least a change every 60 ° that is the electrical angle resolution of the Hall sensors Hu, Hv, and Hw can be detected.

Figure 3 during normal shown in (b), when the output value theta _e of the electrical angle calculation unit 111 sequentially changes 0 ° → 60 ° → 120 ° → 180 ° → ... as the electrical angle change amount calculation unit 114 Subtracts the previous output value (for example, 0 °) from the current output value θ _e (for example, 60 °), and sequentially calculates the electrical angle change amount 60 ° → 60 ° → 60 ° →.

The second determination unit 115 (failure determination means) determines whether or not the electrical angle change amount Δθ is equal to or greater than a predetermined value Δθ1 (second predetermined value). The predetermined value Δθ1 is a value larger than the electrical angle resolution 60 ° of the Hall sensors Hu, Hv, and Hw, and is set in advance as a change amount (for example, 180 °) that cannot be output in the normal state. .
When the electrical angle change amount Δθ is equal to or greater than the predetermined value Δθ1, the second determination unit 115 outputs the flag signal F2: ON to the integration processing unit 116. On the other hand, when the electrical angle change amount Δθ is less than the predetermined value Δθ1, the second determination unit 115 outputs the flag signal F2: OFF to the integration processing unit 116.

  Based on the flag signal F1 input from the first determination unit 113 and the flag signal F2 input from the second determination unit 115, the integrated processing unit 116 (failure determination unit) performs hall sensors Hu, Hv, Hw. It is determined whether at least one of them is out of order. The integrated processing unit 116 includes a counter circuit (not shown) that counts the cumulative number of times that the flag signal F1 or F2 has been turned ON.

The integrated processing unit 116 outputs a failure notification signal Q to the failure notification device 500 when at least one of the Hall sensors Hu, Hv, and Hw is defective. The above-described failure alarm device 500 is a monitor that displays an image, a speaker that outputs sound, or the like.
The processing content of the integrated processing unit 116 will be described later.

<Operation of failure detection device>
Hereinafter, the operation of the failure detection apparatus 110 (control apparatus 100) illustrated in FIG. 4 will be described by taking the case where the motor 400 is rotating forward as an example.

FIG. 5A shows a case where the Hall sensor Hu corresponding to the U phase has failed and is always outputting an ON signal (High sticking: 1). In this case, the combination of digital signals (H, H, L) → (H, H, L) → (H, H, H) → (H, H, H) → from the hall sensors Hu, Hv, Hw to the failure detection device 110 over time. ... is entered.
In FIG. 5 (a), the portions different from the normal state of the Hall sensors Hu, Hv, Hw (see FIG. 3 (b)) are shaded (FIG. 5 (b), FIG. 6, FIG. 7 is the same).

  As shown in FIG. 4, after starting the driving of the motor 400 (START), the control device 100 sets a counter value n = 0 in step S101. The counter value n described above is incremented when a predetermined condition (S103, S106) is satisfied in a counter circuit (not shown) of the integration processing unit 116.

Controller 100 in step S102, the electrical angle calculation unit 111, FIG. 3 (b), calculate the output value theta _e of the electrical angle based on the correspondence relationship shown in (c).
For example, if the digital signal (H, H, L), the electrical angle calculation unit 111 outputs the "0 °" as the output value theta _e of the electrical angle (see Figure 5 (a)). Also, in the case of a digital signal (H, H, H), the electrical angle calculation unit 111 outputs the "-360 °" as the output value theta _e of the electrical angle.

Controller 100 in step S103, determines the output value theta _e of the electrical angle calculation unit 111 whether the (-360 °). That is, the control device 100 determines whether or not the flag signal F1 input from the first determination unit 113 is ON.
If the output value theta _e is (-360 °) (S103 → Yes ), the processing of the control unit 100 proceeds to step S104. On the other hand, when the output value theta _e is not (-360 °) (S103 → No ), the processing of the control unit 100 proceeds to step S105.

In the example shown in FIG. 5A, the digital signals from the hall sensors Hu, Hv, Hw are (H, H, H) at an electrical angle of 120 °, and the output value θ _e = It is -360 degrees.
As described above, when there is a Hall sensor Hu that always outputs a high digital signal, the output values of the Hall sensors Hu, Hv, and Hw that change from moment to moment are all high. It happens once.

In step S104, the control device 100 increments the counter value n.
Next, in step S <b> 105, the control device 100 calculates the electrical angle change amount Δθ by the electrical angle change amount calculation unit 114. That is, the controller 100 calculates the present output value theta _e inputted from the electrical angle calculation unit 111, and the previous output value read from the storage unit 112, an electrical angle variation Δθ by taking the difference of the .

As shown in FIG. 3B, the electrical angle change amount Δθ in the normal state is constant at 60 ° as long as the disturbance and the detection error are small (if the calculation period of the electrical angle change amount Δθ is shortened even in the normal state, Δθ = 0 °).
On the other hand, at the time of the failure shown in FIG. 5A, the electrical angle change amount Δθ changes from moment to moment as 60 ° → 0 ° → −360 ° → 600 ° → 0 ° → 60 ° →. FIG. 5A shows the electrical angle change amount Δθ when the motor 400 is rotated forward.

  In step S106 of FIG. 4, the control device 100 determines whether or not the absolute value | Δθ | of the electrical angle change amount Δθ is equal to or greater than a predetermined value Δθ1. That is, the control apparatus 100 determines whether or not the flag signal F1 input from the second determination unit 115 is ON by the integration processing unit 116. As described above, the predetermined value Δθ1 is a change amount (for example, 360 °) that cannot be output when the Hall sensors Hu, Hv, and Hw are normal, and is set in advance.

  When the absolute value | Δθ | of the electrical angle change amount is equal to or greater than the predetermined value Δθ1 (S106 → Yes), the process of the control device 100 proceeds to step S107. On the other hand, if the absolute value | Δθ | of the electrical angle change amount is less than the predetermined value Δθ1 (S106 → No), the process of the control device 100 proceeds to step S108.

  In the example shown in FIG. 5A, in the state where the actual electrical angle is 180 °, the electrical angle change amount Δθ = 240 ° − (− 360 °) = 600 °, which is much higher than that in the normal state. Is getting bigger. In this case, since the absolute value 600 ° of the electrical angle change amount Δθ is equal to or greater than the predetermined value Δθ1 (= 360 °), the second determination unit 115 outputs the flag signal F2: ON.

In step S107 in FIG. 4, the control device 100 increments the counter value n.
Next, in step S108, the control device 100 determines whether or not the counter value n has reached the threshold value N. The threshold value N is a natural number set in advance in order to reduce the influence of disturbances and detection errors.
When the counter value n reaches the threshold value N (S108 → Yes), the process of the control device 100 proceeds to step S109. On the other hand, when the counter value n has not reached the threshold value N (S108 → No), the processing of the control device 100 returns to step S102.

  Note that the processing of steps S102 to S108 shown in FIG. 4 is performed by changing the voltages V (Hu), V (Hv), and V (Hw) at every electrical angle of 60 ° when the Hall sensors Hu, Hv, and Hw are normal. It makes a round in a predetermined time that can be detected.

  In step S109, the control device 100 outputs the failure notification signal Q to the failure notification device 500, and ends the processing (END). As a result, the user can quickly know that the Hall sensor Hu has failed.

<About other examples>
Next, the failure detection processing of the Hall sensors Hu, Hv, and Hw will be described sequentially with reference to FIGS. 5 (b), 6 and 7. Since the processing contents of the control device 100 are the same as those in the flowchart shown in FIG. 4, the following description will be given focusing on the flag signals F1 and F2.

FIG. 5B is an explanatory diagram when the Hall sensor Hu fails and always outputs an OFF signal (Low sticking: 1). In this case, since the output value θ _e = −360 ° when the actual electrical angle is 300 °, the first determination unit 113 outputs the flag signal F1: ON.
In addition, when the actual electrical angle is 0 ° or 300 °, the absolute value of the electrical angle change Δθ from the previous time is equal to or greater than the predetermined value Δθ1 (= 360 °). : ON is output.

  FIG. 6A is an explanatory diagram when the Hall sensors Hu and Hv are out of order and always output an ON signal (High sticking: 2). In this case, the flag signal F1: ON is output from the first determination unit 113 when the actual electrical angle is 120 °, 180 °, and 240 °. Further, when the actual electrical angle is 120 ° or 300 °, the second determination unit 115 outputs a flag signal ON.

  FIG. 6B is an explanatory diagram when the Hall sensors Hu and Hv are out of order and always output an OFF signal (Low sticking: 2). In this case, the flag signal F1: ON is output from the first determination unit 113 when the actual electrical angle is 0 °, 60 °, or 300 °. Further, when the actual electrical angle is 120 ° or 300 °, the second determination unit 115 outputs a flag signal ON.

FIG. 7A is an explanatory diagram in the case where all the Hall sensors Hu, Hv, and Hw have failed and are always outputting ON signals (High sticking: 3). In this case, the flag signal F1: ON is continuously output from the first determination unit 113, and the flag signal F2 output from the second determination unit 115 is always OFF. Thus, even when the flag signal F2: ON is not output from the second determination unit 115, the counter value n is incremented in step S104 of FIG.
Note that FIG. 7B is the same as that in FIG.

  5 to 7 show the electrical angle change amount Δθ when the motor 400 is rotated forward, but even when the motor 400 is rotated in the reverse direction, the electrical angle change amount Δθ can be calculated by the same method as described above. Good.

<Effect>
According to the failure detection apparatus 110 according to the present embodiment, when the combination of digital signals input from the hall sensors Hu, Hv, and Hw is all high or all low, the electrical angle calculation unit 111 is the first electrical angle. A predetermined value “−360 °” is output. That is, the first predetermined value is set as a value that cannot be output as an electrical angle when the plurality of hall sensors Hu, Hv, and Hw are all normal (the electrical angle is not less than 0 ° and not more than 360 °). .

  If the electrical angle calculation unit 111 outputs a value (for example, 0 °) that may be output even when it is a digital signal (H, H, H), the Hall sensor has actually failed. It is difficult to determine whether or not the data has been output due to this.

On the other hand, in this embodiment, when the digital signals from the Hall sensors Hu, Hv, and Hw are (H, H, H) or (L, L, L), the electrical angle calculation unit 111 is intentionally set to “−360. “°” is output. As a result, the states of the digital signals (H, H, H) and (L, L, L) can be clearly distinguished from the normal state, and the reliability of the detection result by the failure detection device 110 can be improved.
In particular, according to the present embodiment, one or two of the conventional methods for determining that there is a failure only when the digital signals from the Hall sensors Hu, Hv, and Hw are all high or all low. Even when the Hall sensor fails, the failure can be detected early and accurately.

In addition, the electrical angle change amount calculation unit 114 calculates the electrical angle change amount Δθ using the calculation result by the electrical angle calculation unit 111 and compares it with a predetermined value Δθ1. Here, the predetermined value Δθ1 is a value larger than the electrical angle resolution of the plurality of Hall sensors Hu, Hv, Hw (that is, a value that cannot be outputted as a change amount of the electrical angle calculated every predetermined time). Is set as
Thus, the electrical angle variation Δθ in addition to the output value theta _e of the electrical angle also be used for fault detection, it can quickly and appropriately detect the failure of the Hall sensor.

The electrical angle “−360 °” is not output in the normal state, but is substantially equal to “0 °” when used as a trigonometric function variable. In this way, by outputting a value “−360 °” that is an integer multiple of 360 ° as an electrical angle even in the event of a failure in which a digital signal (H, H, H) or (L, L, L) is output, It is possible to reliably avoid problems in the control process of the motor 400.
Further, by using relatively inexpensive Hall sensors Hu, Hv, and Hw as a detector that detects the electrical angle of the motor 400, the cost required for the detector can be reduced.

≪Modification≫
As mentioned above, although the said embodiment demonstrated the failure detection apparatus 110 which concerns on this invention, this invention is not limited to these description, A various change can be made.
For example, in the above-described embodiment, the case where three hall sensors Hu, Hv, and Hw are installed in the motor 400 has been described. However, the present invention is not limited to this. That is, the number of Hall sensors may be changed as appropriate according to the number of poles of the motor 400.

Moreover, in the said embodiment, when the signal input from Hall sensor Hu, Hv, Hw is (H, H, H) or (L, L, L), the electrical angle calculating part 111 makes 1st predetermined value " However, the present invention is not limited to this. That is, the first predetermined value may be set to “any value less than 0 ° or greater than 360 °” that does not include 0 ° to 360 °.
In the above case, the first predetermined value is preferably set as an angle (60 ° × n) less than 0 ° or greater than 360 °. Note that n is an integer excluding 0 to 6 (that is,..., -3, -2, -1, 7, 8, 9,...). For example, since the electrical angles of −180 ° and 540 ° are substantially equal to the electrical angle of 180 ° in the control of the motor 400, it is possible to prevent problems in the control of the motor 400.

Further, the electrical angle change amount calculation unit 114 (see FIG. 2) may be omitted from the failure detection device 110, and accordingly, the processing of steps S105 to S107 in FIG. 4 may be omitted. In this case, with reference to the output value theta _e from the electrical angle calculation unit 111, the first determination unit 113 determines the presence or absence of fault.
Further, when the output value “−360 °” is input at least once from the electrical angle calculation unit 111 and the change amount greater than the predetermined value Δθ1 is input at least once from the electrical angle change amount calculation unit 114, the integration is performed. The processing unit 116 may determine that there is a failure.

  Moreover, although the said embodiment demonstrated the case where Hall sensors Hu, Hv, and Hw were installed in the motor 400 rotated forward or reverse according to operation by a driver | operator, it is not restricted to this. That is, the present invention can be similarly applied even when the motor 400 rotates only in one direction.

In the embodiment, a gear mechanism is connected to the rotation shaft k (see FIG. 1) of the motor 400, and a piston (not shown) is provided in the cylinder (not shown) in accordance with the forward / reverse rotation of the motor 400. However, the present invention is not limited to this. That is, the embodiment can be applied to various motors used for other uses such as electric power steering.
Further, in accordance with the above-described embodiment, the difference between the hydraulic pressure of the cylinder corresponding to the rotation angle / rotational speed (cylinder stroke amount) of the motor 400 and the hydraulic pressure actually generated in the cylinder is a predetermined value or more. In this case, the failure detection device 110 may determine that there is a failure.

DESCRIPTION OF SYMBOLS 100 Control apparatus 110 Failure detection apparatus 111 Electrical angle calculation part (electrical angle calculation means)
112 memory | storage part 113 1st determination part (failure determination means)
114 Electrical angle change calculation unit (electric angle change calculation means)
115 2nd determination part (failure determination means)
116 Integrated processing unit (failure determination means)
200 DC power supply 300 Inverter 400 Motor 500 Failure alarm Hu, Hv, Hw Hall sensor

Claims (3)

A digital signal corresponding to a change in magnetic flux accompanying the driving of the motor is input from a plurality of hall sensors installed in the motor, and an electric angle for calculating the electrical angle of the motor corresponding to each combination of the digital signals Angle calculation means;
Failure determination means for determining whether at least one of the plurality of Hall sensors has failed based on the electrical angle calculated by the electrical angle calculation means ;
An electrical angle change amount calculating means for calculating an electric angle change amount calculated by the electric angle calculating means every predetermined time, and outputting to the failure determining means ,
When the combination is all high or all low, the electrical angle calculation means outputs a first predetermined value less than 0 ° or greater than 360 ° as the electrical angle of the motor to the failure determination means,
The failure determination means receives the first predetermined value from the electrical angle calculation means at least once , and the absolute value from the electrical angle change amount calculation means exceeds the electrical angle resolution of the plurality of Hall sensors. A failure detection device, wherein when at least one change amount greater than a second predetermined value is input at least once, it is determined that at least one of the plurality of hall sensors has failed. The failure detection apparatus according to claim 1 , wherein the first predetermined value is set in advance as an angle (60 ° × n) less than 0 ° or greater than 360 °.
Here, n is an integer excluding 0-6. The failure determination means determines whether or not at least one of the plurality of hall sensors installed in the motor that rotates forward or reverse according to an operation by a driver has failed. The failure detection device according to claim 1 or 2 .

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