JP5076839B2 - Electromagnetic actuator control apparatus and method - Google Patents

Description

  The present invention relates to a technical field of an electromagnetic actuator control device and method for detecting a position of a plunger in an electromagnetic actuator, for example, for engaging a dog clutch of a vehicle.

  As this type of electromagnetic actuator control device, there is one that detects the position of the plunger indirectly using hardware such as a position sensor, and indirectly detects the position of the plunger without using hardware.

  For example, Patent Document 1 discloses a technique for detecting the position of a plunger from a current change caused by an induced voltage of a coil.

  Patent Document 2 discloses a technique of controlling the current flowing in the coil to be constant and detecting the seating of the plunger from the duty ratio at that time.

JP-A-6-213257 JP 2000-283327 A

  However, in the above-described technique, for example, when the moving speed of the plunger decreases due to dragging or the like, the induced voltage and the current change irregularly, and there is a possibility that the position of the plunger cannot be detected accurately. There is a problem.

  The present invention has been made in view of the above-described problems, for example, and an object thereof is to provide an electromagnetic actuator control device and method capable of accurately detecting the position of a plunger.

In order to solve the above problems, an electromagnetic actuator control device according to the present invention is a coil that is wound, a plunger inserted into the coil, and a current output means that drives the plunger by energizing the coil. Current control means for performing pulse width modulation control on the energization so as to make the time average of the current related to the energization constant, induced voltage specifying means for specifying the induced voltage by driving the plunger, When the identified induced voltage is zero, inductance calculating means for calculating the inductance of the coil, position detecting means for detecting the position of the plunger based on the calculated inductance, and the temperature of the coil Temperature detecting means for detecting; and resistance correcting means for correcting the resistance of the coil based on the detected temperature; Specifying means, based on the corrected resistance, it identifies the induced voltage.

  According to the electromagnetic actuator control device of the present invention, during the operation, first, the coil wound by the current output means is energized, and the plunger inserted in the coil is driven. That is, the plunger is driven by using an electromagnet as the coil. Here, “driving” means reciprocating the inside of the coil (that is, the internal space extending in a column shape surrounded by the wound coil along the extension axis of the column). .

  Here, in the present invention, in particular, the pulse width modulation control is performed on the energization so that the time average of the current related to the energization is constant by the current control means. Here, “current time average” means a time average value of current values, that is, an average value of current values at each time within a predetermined period. Further, “constant” does not have to be a strictly constant value, but may be a value that falls within a certain range. “Pulse width modulation (PWM)” is a method of controlling the on and off periods of energization by changing the width and interval (ie, duty ratio) of the energized pulses.

  Next, the induced voltage generated when the plunger is driven by the induced voltage specifying means is specified. That is, the value of the induced voltage (that is, the voltage value) is specified. Here, the induced voltage may be specified by calculation, may be specified by obtaining from a map, may be specified by estimation, or may be specified by detection, measurement, or measurement. May be. Furthermore, you may specify combining these various methods. The induced voltage can be calculated using, for example, the voltage applied by the current output means and the resistance of the coil.

  Subsequently, when the specified induced voltage is zero, the inductance of the coil is calculated by the inductance calculating means. When the induced voltage is zero, the influence of current distortion due to dielectric pressure can be avoided, so that an accurate inductance value can be calculated. Note that “the induced voltage is zero” means that the dielectric voltage value is zero, and represents a state where the plunger is stationary with respect to the coil. Further, the induced voltage does not have to be strictly zero, and may be a value close to zero so that the inductance can be accurately calculated. In other words, it may be substantially zero. That is, the inductance can be calculated not only when the above-described plunger is stationary with respect to the coil but also when the plunger is operating very slowly with respect to the coil.

  When the inductance is calculated, the position detecting means detects the position of the plunger based on the inductance. The inductance varies depending on the relative position of the plunger with respect to the coil, and typically decreases as the plunger is inserted deeper into the coil. For this reason, for example, it is possible to detect the position of the plunger from the inductance by obtaining a mathematical expression or the like representing the relationship between the inductance and the position of the plunger in advance.

  As described above, according to the electromagnetic actuator control device of the present invention, it is possible to detect the position of the plunger with higher accuracy by a relatively simple calculation.

  In one aspect of the electromagnetic actuator control device of the present invention, the inductance calculating means calculates the inductance based on a pulse duty ratio in the pulse width modulation control.

  According to this aspect, the inductance of the coil is calculated based on the duty ratio of the pulse in PWM. For example, the greater the inductance, the less current flows. Therefore, when the inductance is large, the time average of the current is made constant, so that the time during which energization is turned on by PWM becomes long. That is, the duty ratio increases. As described above, the inductance and the duty ratio are related to each other. For example, the inductance can be more easily calculated by expressing the relationship between the inductance and the duty ratio by a mathematical expression or the like.

  As described above, according to the electromagnetic actuator control device according to this aspect, the inductance can be more easily calculated based on the duty ratio.

  In another aspect of the electromagnetic actuator control device of the present invention, the electromagnetic actuator control device further includes first current detection means for detecting a current value of the energization after the pulse width modulation control is performed, wherein the inductance calculation means is the detected The inductance is calculated based on the change rate of the current value.

  According to this aspect, first, the current value of energization after the PWM is performed is detected by the first detection means. That is, the current value of the current controlled so that the time average is constant is detected. Then, the inductance calculation means calculates the inductance based on the detected change rate of the current value. For example, the larger the inductance, the less the current flows, and the smaller the rate of change of the detected current value. In this way, the inductance and the rate of change of the current value are related to each other. For example, the inductance can be calculated more easily by expressing the relationship between the rate of change of the inductance and the current value by a mathematical expression or the like. Is possible.

  As described above, according to the electromagnetic actuator control device according to this aspect, it is possible to more easily calculate the inductance based on the rate of change of the current value.

  In the aspect further comprising the first current detection means described above, the first current detection means is a longer period of the period in which the energization is turned on and the period in which the current is turned off by the pulse width modulation control. You may comprise so that the said electric current value may be detected according to a start.

  If comprised in this way, the electric current value of electricity supply after PWM is performed will match | combine with the longer period (namely, synchronously) between the period when electricity supply is turned on, and the period when it is turned off. ) Is detected. More specifically, a comparison is made between the length of time during which the energization is turned on and the time during which the current is turned off. When the off period is long, the current value is detected during the off period.

  As described above, by detecting the current value in the longer period, it is possible to lengthen the time for detecting the current value as compared to the case of detecting in the shorter period. For this reason, for example, A / D (Analog to Digital) conversion or the like can be performed more suitably, and the accuracy of detecting the current value can be improved.

  Alternatively, in an aspect further including the first current detection means, in another aspect of the electromagnetic actuator control device of the present invention, the first current detection means is switched on and off by the pulse width modulation control. You may comprise so that the said electric current value may be detected immediately before.

  With this configuration, the current value of energization after the PWM is performed is detected immediately before the energization is switched on and off. The term “immediately before” here means a time when the influence of electromagnetic waves described in detail below can be reduced or eliminated.

  In PWM, electromagnetic waves are generated when energization is switched on and off (hereinafter referred to as “switching” as appropriate). For this reason, noise is superimposed on the electric signal of the current value detected at the time of switching, and the detection accuracy may be deteriorated.

  However, in this embodiment, in particular, since the current value is detected immediately before switching, the influence of electromagnetic waves can be reduced or eliminated. Therefore, it is possible to prevent noise from being superimposed on the detection signal and improve detection accuracy.

  In another aspect of the electromagnetic actuator control device of the present invention, the electromagnetic actuator control device further includes a temperature detection unit that detects the temperature of the coil, and a resistance correction unit that corrects the resistance of the coil based on the detected temperature, The voltage specifying unit specifies the induced voltage based on the corrected resistance.

  According to this aspect, first, the temperature of the coil is detected by the temperature detecting means. In addition to directly detecting the temperature of the coil, the temperature detecting means may indirectly detect the temperature from, for example, the oil temperature of a member disposed around the coil.

  Subsequently, the resistance of the coil is corrected by the resistance correction means based on the detected temperature. The resistance of the coil varies with temperature, typically increasing with increasing temperature and decreasing with decreasing temperature. Therefore, by correcting the resistance based on the detected temperature, it becomes possible to know a more accurate coil resistance.

  Then, the induced voltage is specified based on the corrected resistance. As described above, the resistance of the coil is corrected to a more accurate value. Therefore, in this aspect, it is possible to specify the induced voltage more accurately.

  In another aspect of the electromagnetic actuator control device of the present invention, voltage detection means for detecting a voltage applied to the coil, second current detection means for detecting a current flowing through the coil, the detected voltage, and the Resistance correction means for correcting the resistance of the coil based on the current detected by the second current detection means, and the induced voltage specifying means specifies the induced voltage based on the corrected resistance. To do.

  According to this aspect, first, the voltage applied to the coil is detected by the voltage detection means. Further, the current flowing through the coil is detected by the second current detection means. The second current detection means may be the same as the first current means described above.

  Subsequently, the resistance of the coil is corrected by the resistance correcting unit based on the detected voltage and the current detected by the second current detecting unit. That is, the resistance of the coil is corrected to a more accurate value based on the voltage actually applied to the coil and the flowing current.

  Then, the induced voltage is specified based on the corrected resistance. As described above, the resistance of the coil is corrected to a more accurate value. Therefore, in this aspect, it is possible to specify the induced voltage more accurately.

  In another aspect of the electromagnetic actuator control device of the present invention, the electromagnetic actuator control device further includes a deviation monitoring unit that monitors a deviation of the current subjected to the pulse width modulation control, and the induced voltage specifying unit includes the deviation exceeding a predetermined threshold value. In this case, the induced voltage is not specified.

  According to this aspect, the deviation of the current subjected to the PWM is monitored by the deviation monitoring unit. The “deviation” here means a value indicating variation in current value, duty ratio, and the like, and becomes large when, for example, a disconnection or a failure occurs in the apparatus.

  Here, in this aspect, in particular, when the deviation exceeds a predetermined threshold, the induced voltage is not specified. That is, when the deviation exceeds a predetermined threshold value, it is determined that the control by the current control means is not properly performed, and the plunger position detection operation is not performed. The “predetermined threshold value” is a value that makes it impossible to accurately identify the induced voltage when the deviation exceeds this value.

  Even if the induced voltage is specified when the deviation exceeds the predetermined threshold value, the inductance cannot be accurately calculated because the specified induced voltage is not an accurate value. Therefore, when the deviation exceeds a predetermined threshold value, it is difficult to detect the position of the plunger.

  However, in this embodiment, in particular, by monitoring the deviation of the current, it is possible to eliminate a unique situation where the current is not properly controlled. For this reason, it is possible to prevent an inaccurate induced voltage from being specified. Therefore, the position of the plunger can be detected more accurately.

  In another aspect of the electromagnetic actuator control apparatus of the present invention, the electromagnetic actuator control device further includes saturation monitoring means for monitoring whether or not the current control means is saturated, and the induced voltage specifying means is that the current control means is saturated. In this case, the induced voltage is not specified.

  According to this aspect, the saturation monitoring unit monitors whether the current control unit is saturated. Here, “saturation” means a state where control exceeding the processing capability of the current control means is required and control cannot be performed appropriately.

  Here, in this embodiment, particularly when the current control means is saturated, the induced voltage is not specified. That is, when the current control means is saturated, it is determined that the control by the current control means is not properly performed, and the plunger position detection operation is not performed.

  Even if the induced voltage is specified when the current control means is saturated, the inductance cannot be accurately calculated because the specified induced voltage is not an accurate value. Therefore, when the deviation exceeds a predetermined threshold value, it is difficult to detect the position of the plunger.

  However, in this embodiment, in particular, by monitoring the saturation of the current control means, it is possible to eliminate a unique situation where the current is not properly controlled. For this reason, it is possible to prevent an inaccurate induced voltage from being specified. Therefore, the position of the plunger can be detected more accurately.

  In another aspect of the electromagnetic actuator control device of the present invention, a saturation monitoring means for monitoring whether or not the current control means is saturated, and when the current control means is saturated, Current value control means for reducing the time average to a value at which the current control means is not saturated.

  According to this aspect, the saturation monitoring unit monitors whether the current control unit is saturated. And especially in this aspect, when a current control means is saturated, a current value control means reduces the time average of the electric current which concerns on electricity supply to the value which a current control means does not saturate. The saturation of the current control means occurs when the output voltage exceeds the processing capability of the current control means, for example, when a request for outputting a very high current is made. Therefore, it is possible to prevent the current control means from being saturated by reducing the time average of the current related to energization. If the current control means is not saturated, the time average of the current related to energization may be increased.

  As described above, by eliminating the saturation of the current control means, the time average of the current related to energization is controlled to be constant. Therefore, the position of the plunger can be detected. That is, in this aspect, by providing the saturation monitoring means, it is possible to eliminate the situation where the plunger position cannot be detected.

  In the aspect further including the saturation monitoring unit and the current value control unit described above, the induced voltage specifying unit may be configured not to specify the induced voltage when the current control unit is saturated.

  With this configuration, when the current control means is saturated, the induced voltage is not specified. That is, when the current control means is saturated, it is determined that the control by the current control means is not properly performed, and the plunger position detection operation is not performed. Even if the induced voltage is specified when the current control unit is saturated, the inductance cannot be accurately calculated because the control by the current control unit is not properly performed. Therefore, it is difficult to detect the position of the plunger.

  However, in this embodiment, in particular, by monitoring the saturation of the current control means, it is possible to eliminate a unique situation where the current is not properly controlled. Further, when the current value control means decreases the time average of the current related to energization and the saturation of the current control means is eliminated, the induced voltage is specified. That is, when the current control unit is saturated, the position detection operation is not performed, and the position detection operation can be performed after the saturation is canceled. Therefore, in this aspect, the position of the plunger can be detected more accurately.

  In another aspect of the electromagnetic actuator control device of the present invention, the current output means sets the time average of the current relating to the energization to the holding current value after the position detection means detects the position of the plunger.

  According to this aspect, after the position of the plunger is detected, the current output means sets the time average of the current related to energization as the holding current value. Note that the “holding current value” is a current value when the plunger is driven without performing position detection, and is a value that is lower by not requiring position detection. Therefore, when the position of the plunger has already been detected and it is not necessary to perform further position detection, energy loss can be reduced by setting the time average of the current as the holding current value.

  In another aspect of the electromagnetic actuator control device of the present invention, the current output means includes current conversion means for converting the current related to the energization into an alternating current.

  According to this aspect, the current output means has the current conversion means for converting the current related to energization into the alternating current, and can output the alternating current to the coil. By making the output current an AC current, the applied DC voltage component is doubled, so that the duty ratio and the like can be detected more accurately. Therefore, the induced voltage can be specified more accurately, and the accuracy of detecting the position of the plunger can be improved.

  In the aspect in which the current output unit includes the current conversion unit, the current conversion unit includes a plurality of switching units, and when an abnormality is detected in at least one of the plurality of switching units. The operation may be performed by other switching means in which the abnormality is not detected.

  If comprised in this way, the electric current conversion means will have a some switching means, and will convert an electric current into an alternating current by switching each switching means. That is, the direction of the current can be changed by switching on and off of energization by each switching means.

  Here, when an abnormality is detected in at least one of the plurality of switching means, the operation is performed by another switching means in which no abnormality is detected. That is, when at least one switching unit does not operate normally due to a failure or the like, the current is converted into an alternating current by another normally operating switching unit. Depending on the location and number of switching means where an abnormality is detected, the function of converting current to alternating current may be lost, but the current output means can output current. If so, it is possible to detect the position of the plunger.

  As described above, when the current converting means has a plurality of switching means, even if an abnormality is detected in the switching means, the operation can be performed by other normal switching means. That is, the reliability of the apparatus is enhanced by having a plurality of switching means.

  Alternatively, in an aspect in which the current output means includes current conversion means, the plunger is connected to the plunger, and the plunger is moved in a direction different from the drive by the energization by the restoring force accumulated by the drive of the plunger by the energization. The current output means further outputs a current in a direction opposite to that during energization so as to reduce a magnetic force remaining in the plunger when the plunger is driven by the spring. You may comprise as follows.

  If comprised in this way, the spring is connected to the plunger, The plunger is driven in the direction different from the drive by electricity supply with the restoring force stored in the spring by the drive by electricity supply.

  The plunger has a magnetic force when driven by energization. The magnetic force remains slightly after the energization is stopped (that is, when driven by a spring). If the magnetic force remains in the plunger when driven by the spring, the magnetic force acts in a direction different from the direction driven by the spring, and the driving speed of the plunger decreases.

  However, if it is configured to output an alternating current, in the above-described case, it is possible to cancel the magnetic force remaining in the plunger by flowing a current in the direction opposite to that in the case of driving to the coil. is there. Therefore, the plunger can be driven without being affected by the magnetic force when driven by the spring. Therefore, it becomes possible to enhance the response when driving the plunger.

  In another aspect of the electromagnetic actuator control device of the present invention, the plunger is connected to a dog clutch, and is driven by the energization to control the engagement of the dog clutch, and the position detection means is configured as the position of the dog clutch. The position of the plunger is detected.

  According to this aspect, the plunger is connected to the dog clutch, and the engagement of the dog clutch is controlled by driving the plunger. And a position detection means detects the position of a dog clutch by detecting the position of a plunger. Here, as described above, since it is not necessary to use a position sensor or the like for position detection in this aspect, this is a particularly effective means in a transmission mechanism in which it is difficult to arrange a sensor device.

  By detecting the position of the dog clutch, for example, it becomes possible to determine whether or not the dog clutch is in the engagement position, so that the engagement state of the dog clutch can be detected. As a result, since it is possible to know the engagement failure of the dog clutch, etc., it becomes possible to appropriately perform fail safe etc. when a malfunction or the like occurs.

In order to solve the above-described problem, an electromagnetic actuator control method of the present invention is an electromagnetic actuator control method for controlling an electromagnetic actuator including a wound coil and a plunger inserted into the coil. A current output step of driving the plunger by energizing the current, a current control step of performing pulse width modulation control on the energization so as to make the time average of the current related to the energization constant, and the plunger An induced voltage specifying step of specifying an induced voltage by driving, an inductance calculating step of calculating an inductance of the coil when the specified induced voltage is zero, and the plunger based on the calculated inductance a position detection step of detecting a position, and a temperature detection step of detecting a temperature of said coil, said detected temperature And a resistance correction step of correcting the resistance of the coil based on, in the induced voltage specifying step, based on the corrected resistance, identifies the induced voltage.

  According to the electromagnetic actuator control method of the present invention, as in the case of the electromagnetic actuator control device of the present invention described above, the position of the plunger is compared by controlling the time average of the current related to energization to be constant. It is possible to detect with higher accuracy by simple calculation.

  In the electromagnetic actuator control method of the present invention, it is possible to adopt various aspects similar to the various aspects of the electromagnetic actuator control apparatus of the present invention described above.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a case where the electromagnetic actuator control device of the present invention is applied to an electromagnetic actuator that controls a dog clutch of a vehicle will be described as an example.

<First Embodiment>
First, the configuration of the electromagnetic actuator control device according to the first embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing the configuration of the electromagnetic actuator control device according to the first embodiment.

  1, the electromagnetic actuator control device according to the present embodiment includes a current output unit 110 that is an example of the “current output unit” of the present invention, and a current control unit 120 that is an example of the “current control unit” of the present invention. The electromagnetic actuator 130 including the “coil” and “plunger” of the present invention, the current detection unit 140 as an example of the “first current detection unit” of the present invention, and the “induced voltage specifying unit” of the present invention An induced voltage specifying unit 150 which is an example, a resistance correcting unit 160 which is an example of the “resistance correcting unit” of the present invention, an inductance calculating unit 170 which is an example of the “inductance calculating unit” of the present invention, and “ The position detection unit 180 is an example of “position detection means”.

  The current output unit 110 is a power source such as a battery, for example, and outputs a current for operating the apparatus.

  The current control unit 120 is a circuit including, for example, a transistor and a capacitor, and performs pulse width modulation control on the current output from the current output unit 110.

  The electromagnetic actuator 130 includes a coil, a plunger inserted into the coil, a yoke, and the like, and the plunger is driven by a magnetic force generated by passing a current through the coil. Further, the plunger can be driven in a direction opposite to the drive by energization by being connected to a spring or the like. The dog clutch 500 is connected to the plunger, and the engagement of the dog clutch can be controlled by driving the plunger.

  The current detector 140 is an ammeter, for example, and detects the current value after being controlled by the current controller 120.

  The induced voltage specifying unit 150, the resistance correcting unit 160, the inductance calculating unit 170, and the position detecting unit 180 include, for example, an arithmetic circuit, a memory, and the like, and perform arithmetic processing on the input data and output the obtained result. To do.

  Next, the operation of the electromagnetic actuator control device according to the present embodiment will be described with reference to FIGS. 2 to 5 in addition to FIG. FIG. 2 is a flowchart showing the operation of the electromagnetic actuator control apparatus according to the first embodiment, and FIG. 3 is a graph showing the duty ratio and the current value in the pulse width modulation control. FIG. 4 is a schematic diagram showing an example of a specific configuration of the electromagnetic actuator control device according to the first embodiment, and FIG. 5 is a graph showing the relationship between the inductance and the position of the plunger.

  In FIG. 2, when the operation of the electromagnetic actuator control device according to the first embodiment is started, first, the current control unit 120 controls the time average of the current output from the current output unit 110 to be constant ( Step S1). This control is performed by PWM. For example, the current value is controlled by changing the duty ratio. More specifically, control is performed by switching on and off of energization by performing switching control using a transistor or the like included in the current control unit 120.

  Subsequently, an induced voltage generated by driving the plunger is specified (step S2). The induced voltage e can be specified using, for example, the following formula (1).

e = E-Ri (1)
In Equation (1), E is a voltage applied to the coil, and Ri is the resistance of the coil.

  Here, the resistance Ri is a value corrected by the resistance correction unit 160. For example, the resistance correction unit 160 detects the temperature of the coil by a temperature detection unit which is an example of the “temperature detection unit” of the present invention (not shown), and corrects the resistance based on the detected temperature. The temperature detection unit is, for example, a temperature sensor or the like, and detects the temperature of the coil or a peripheral member of the coil.

  Further, the resistance correction unit 160 detects the value of the current flowing in the coil by causing the current detection unit 140 to have a function as the “second current detection unit” of the present invention, and further detects the voltage value of the present invention (not shown). The resistance may be corrected based on the detected current value and voltage value after the voltage value applied to the coil is detected by the voltage detector that is an example of the “means”.

  By performing the correction as described above, the resistance becomes an appropriate value according to the situation, so that the induced voltage can be specified more accurately.

  When the induced voltage is specified, it is determined whether or not the specified induced voltage is “0” (step S3). In addition, that the induced voltage is “0” means that the plunger is stationary with respect to the coil. Here, if it is determined that the induced voltage is '0' (step S3: YES), the process proceeds to step S4. If it is determined that the induced voltage is not “0” (step S3: NO), the process of step S3 is repeated. Even if the specified induced voltage is not strictly '0' (that is, even when the plunger moves very slowly), the process may proceed to step S4. This is because if the induced voltage is substantially '0', the inductance can be accurately calculated as described in detail below.

  When the induced voltage is “0”, the inductance of the coil is calculated (step S4). The inductance L can be calculated based on the duty ratio in PWM, for example.

  In FIG. 3A, T1 represents a period in which energization is turned on in PWM, and T2 represents a period (that is, one cycle) that is a combination of a period in which power is turned on and a period in which it is turned off. In this case, the current value increases in the period T1 during which energization is performed, and gradually decreases when the energization is turned off.

  In FIG. 3B, when the inductance is larger than in the case of FIG. 3A, the increase in current in the period T1 during which the energization is turned on becomes moderate. For this reason, in the case of FIG. 3A and FIG. 3B, if the time average of the current is set to the same value, the period T1 during which the energization is turned on is shown in FIG. 3B. The case becomes longer than the case of FIG. That is, the duty ratio T1 / T2 in the case of FIG. 3B is larger than that in the case of FIG. Thus, since the relationship that the duty ratio increases as the inductance increases, the inductance can be calculated from the duty ratio by using, for example, a mathematical formula or a table.

  Further, the inductance can be calculated based on, for example, the rate of change of the current flowing through the coil, other than the method of calculating using the duty ratio as described above. That is, it is possible to calculate based on the slope of the current value in the period T1 during which energization is turned on.

  When the inductance is calculated, the position of the plunger is detected based on the calculated inductance (step S5). The inductance varies depending on the relative position of the plunger with respect to the coil, and typically decreases as the plunger is inserted deeper into the coil.

  In FIG. 4, the plunger 220 inserted into the coil 210 is driven rightward in the figure when energized. When the energization is stopped, it is driven leftward in the figure by the restoring force stored in the spring 230 at the time of driving by energization. Here, the position x of the plunger is expressed as ‘0’ when the plunger 220 is inserted deepest into the coil 210. In this case, the position x of the plunger can be calculated by using, for example, the following mathematical formula (2).

L = N ² / {(l−x) / μ ₀ S + P} (2)
In Equation (2), L is the inductance, N is the number of turns of the coil 210, l is the stroke distance of the plunger 220 (that is, the distance within the drivable range), μ ₀ is the vacuum permeability, and S is the inside of the coil 210. It is assumed that the sectional area of the space (that is, the area of the surface perpendicular to the driving direction), P is the magnetic resistance of the yoke.

  In FIG. 5, by further simplifying the relationship of the above-described formula (2), it is possible to detect the position, assuming that the inductance L and the position x of the plunger 220 are substantially proportional, as shown in the graph.

  Further, the relationship between the position x of the plunger 220 and the inductance L may be nonlinear due to the influence of overcurrent loss, skin effect of magnetic flux, etc., but the measurement of the position x and the inductance L of the plunger 220 under various conditions in advance. By performing the above and the like and creating a table, more accurate position detection can be performed.

  After the plunger 220 is positioned, control is performed so that the current value related to energization becomes the holding current value (step S6). Since the holding current value is lower than the current value when position detection is performed (that is, the current value in steps S1 to S5), the power consumption of the apparatus can be reduced.

  As described above, according to the electromagnetic actuator control device according to the present embodiment, the position of the plunger 220 can be detected with higher accuracy by a relatively simple calculation. Therefore, the position of the dog clutch 500 connected to the plunger 220 can be accurately detected, and the operation such as fail-safe can be performed more appropriately by grasping the engagement state.

Second Embodiment
Next, an electromagnetic actuator control device according to a second embodiment will be described with reference to FIGS. 6 and 7 are block diagrams showing an example of the configuration of the electromagnetic actuator device according to the second embodiment. The second embodiment differs from the first embodiment in the configuration and operation for controlling the current, and the configuration and operation related to position detection and the like are substantially the same. Therefore, in the third embodiment, portions different from those in the first embodiment will be described in detail, and descriptions of overlapping portions will be omitted as appropriate.

  In FIG. 6, the electromagnetic actuator control device according to the second embodiment includes a deviation monitoring unit 310 that is an example of the “deviation monitoring unit” of the present invention. The deviation monitoring unit 310 monitors the deviation of the current subjected to PWM (that is, a value indicating variation in the current value, duty ratio, etc.), and when the deviation exceeds a predetermined threshold, the induced voltage specifying unit 150 induces the deviation. Ensure that the voltage is not specified.

  The deviation of the current described above becomes large, for example, when a disconnection or a failure occurs in the apparatus and the current is not properly controlled. That is, by monitoring the current deviation, it is possible to eliminate a unique situation where the induced voltage cannot be accurately specified because the current is not properly controlled. Therefore, the position of the plunger can be detected more accurately.

  Further, a saturation monitoring unit 320 may be provided instead of or in addition to the deviation monitoring unit 310 described above.

  In FIG. 7, the electromagnetic actuator control device according to the second embodiment includes a saturation monitoring unit 320 and a current value control unit 330. The saturation monitoring unit 320 monitors whether or not the current control unit 120 is saturated (that is, whether or not an operation that exceeds the processing capability of the current control unit 120 is performed). When the current control unit 120 is saturated, the induced voltage cannot be accurately specified because the current is not properly controlled. For this reason, when the current control unit 120 is saturated, the specification of the induced voltage in the induced voltage specifying unit 150 is stopped.

  Furthermore, when the current control unit 120 is saturated, the current value control unit 330 decreases the current related to energization so that the current control unit 120 does not saturate. The saturation of the current control unit 120 occurs when the output voltage exceeds the processing capability of the current control unit 120, for example, when a request for outputting a very high current is made. Therefore, the saturation of the current control unit 120 can be eliminated by performing the control for reducing the current value as described above. Hereinafter, the control by the current value control unit 330 will be described in detail with reference to FIG. FIG. 8 is a graph showing the current value related to the control of the current value control unit, the output voltage, and the position of the plunger in time series.

  In FIG. 8, the current value control unit 330 controls a current value related to energization (that is, time average of current) by changing a current command indicating a current value required for the current control unit 120. Further, the saturation monitoring unit 320 monitors the saturation of the current control unit 120 depending on whether or not the output voltage exceeds the saturation line.

  At time t1, a current command is first issued, and the current value increases accordingly. At time t2, since the output voltage exceeds the saturation line, it is determined that the current control unit 120 is saturated, and the current value control unit 330 decreases the current command. At time t3, since the output voltage is on the saturation line, the current value control unit 330 stops reducing the current command. At time t4, since the position of the plunger changes rapidly, the output voltage again exceeds the saturation line. For this reason, the current value control unit 330 lowers the current command again. At time t5, the position of the plunger becomes “0”, and the driving is stopped, so that the output voltage rapidly decreases. At time t6, since the output voltage falls below the saturation line, the current command is increased. Finally, at time t6, since the output voltage is again on the saturation line, the current value control unit 330 stops increasing the current command.

  As described above, when the current value is controlled by the current value control unit 330, a unique situation in which the induced voltage cannot be accurately specified can be eliminated, so that the position detection cannot be performed and the state can be performed. It can be recovered.

  As described above, according to the electromagnetic actuator control device according to the second embodiment, the unique situation can be eliminated or eliminated as compared with the first embodiment described above. Can be detected.

<Third Embodiment>
Next, an electromagnetic actuator control device according to a third embodiment will be described with reference to FIG. FIG. 9 is a schematic diagram showing an example of a specific configuration of the electromagnetic actuator control device according to the third embodiment. Further, the third embodiment differs greatly from the first embodiment described above in that it includes a power conversion unit, and the other configurations are generally the same. For this reason, in 3rd Embodiment, the structure and operation | movement of a power converter are demonstrated in detail, and description is abbreviate | omitted suitably about another part.

  In FIG. 9, the electromagnetic actuator control device according to the third embodiment includes a transistor 410 which is an example of the “switching means” of the present invention. The four transistors 410 constitute a current converter 400 that is an example of the “power converter” of the present invention. In other words, each transistor 410 is turned on and off to allow an alternating current to flow through the coil 210. The transistor 410 also has a function as the above-described current control unit 120 (see FIG. 1).

  By allowing an alternating current to flow, for example, the applied DC voltage component is doubled, so that the duty ratio and the like can be detected more accurately. Therefore, the induced voltage can be specified more accurately, and the position detection accuracy of the plunger 220 can be improved.

  In this embodiment, when an abnormality is detected in at least one of the transistors 410, the operation is performed in the other transistor 410 in which no abnormality is detected. That is, when at least one transistor 410 does not operate normally due to a failure or the like, the current is converted into an alternating current by another normally operating transistor 410. Depending on the location and number of transistors 410 in which an abnormality is detected, the function of converting current into alternating current may be lost, but if current can be output, It is possible to detect the position of the plunger 220. Thus, in the third embodiment, an effect that the reliability of the apparatus is improved is also obtained.

  Further, in the present embodiment, when the plunger 220 is driven by the restoring force of the spring 230, the magnetic force remaining in the plunger 220 can be canceled by flowing a current in the direction opposite to that when driving by energization. Is possible. If driving by the spring 230 is performed while the magnetic force remains in the plunger 220, the magnetic force acts in a direction different from the direction driven by the spring 230, and thus the driving speed of the plunger 220 decreases. However, in the present embodiment, since the remaining magnetic force can be canceled out, when driven by the spring 230, it is possible to drive without being affected by the magnetic force. Therefore, it is possible to enhance the feeling of response when driving the plunger 220.

  As described above, according to the electromagnetic actuator control device according to the third embodiment, not only can the position of the plunger 220 be detected more accurately than in the first embodiment described above, but also the reliability of the device. The effect of improving the property and the response of the plunger is also obtained.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. And methods are also within the scope of the present invention.

It is a block diagram which shows the structure of the electromagnetic actuator control apparatus which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the electromagnetic actuator control apparatus which concerns on 1st Embodiment. It is a graph which shows the duty ratio and current value in pulse width modulation control. It is the schematic which shows an example of the specific structure of the electromagnetic actuator control apparatus which concerns on 1st Embodiment. It is a graph which shows the relationship between an inductance and the position of a plunger. It is a block diagram (the 1) which shows an example of a structure of the electromagnetic actuator apparatus which concerns on 2nd Embodiment. It is a block diagram (the 2) which shows an example of a structure of the electromagnetic actuator apparatus which concerns on 2nd Embodiment. It is a graph which shows the electric current value which concerns on control of an electric current value control part, a voltage value, and the displacement of a plunger in time series. It is the schematic which shows an example of the specific structure of the electromagnetic actuator control apparatus which concerns on 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 110 ... Current output part, 120 ... Current control part, 130 ... Electromagnetic actuator, 140 ... Current detection part, 150 ... Induced voltage specific part, 160 ... Resistance correction part, 170 ... Inductance calculation part, 180 ... Position detection part, 210 ... Coil, 220 ... Plunger, 230 ... Spring, 310 ... Deviation monitoring unit, 320 ... Saturation monitoring unit, 330 ... Current value control unit, 400 ... Current conversion unit, 410 ... Transistor, 500 ... Dog clutch

Claims (16)

A wound coil;
A plunger inserted into the coil;
A current output means for driving the plunger by energizing the coil;
Current control means for performing pulse width modulation control on the energization so as to make the time average of the current related to the energization constant;
An induced voltage specifying means for specifying an induced voltage by driving the plunger;
Inductance calculation means for calculating the inductance of the coil when the identified induced voltage is zero;
Position detecting means for detecting the position of the plunger based on the calculated inductance ;
Temperature detecting means for detecting the temperature of the coil;
Resistance correction means for correcting the resistance of the coil based on the detected temperature;
With
The electromagnetic actuator control device, wherein the induced voltage specifying means specifies the induced voltage based on the corrected resistance .   The electromagnetic actuator control device according to claim 1, wherein the inductance calculating unit calculates the inductance based on a duty ratio of a pulse in the pulse width modulation control. A first current detecting means for detecting a current value of the energization after the pulse width modulation control is performed;
The electromagnetic actuator control device according to claim 1, wherein the inductance calculating unit calculates the inductance based on the detected rate of change of the current value.   The first current detection means detects the current value in accordance with the start of the longer period of the period in which the energization is turned on and the period in which the current is turned off by the pulse width modulation control. The electromagnetic actuator control device according to claim 3.   The electromagnetic actuator control device according to claim 3, wherein the first current detection unit detects the current value immediately before the energization is switched on and off by the pulse width modulation control. Voltage detecting means for detecting a voltage applied to the coil;
Second current detection means for detecting current flowing in the coil;
Resistance correction means for correcting the resistance of the coil based on the detected voltage and the current detected by the second current detection means; and
The electromagnetic actuator control device according to any one of claims 1 to 5, wherein the induced voltage specifying unit specifies the induced voltage based on the corrected resistance. Deviation monitoring means for monitoring the deviation of the current subjected to the pulse width modulation control,
The electromagnetic actuator control device according to any one of claims 1 to 6 , wherein the induced voltage specifying unit does not specify the induced voltage when the deviation exceeds a predetermined threshold value. Further comprising saturation monitoring means for monitoring whether or not the current control means is saturated;
The electromagnetic actuator control device according to any one of claims 1 to 6 , wherein the induced voltage specifying unit does not specify the induced voltage when the current control unit is saturated. Saturation monitoring means for monitoring whether the current control means is saturated;
The apparatus further comprises: current value control means for reducing, when the current control means is saturated, a time average of the current related to energization to a value at which the current control means is not saturated. electromagnetic actuator control device according to any one of 6. The electromagnetic actuator control device according to claim 9 , wherein the induced voltage specifying unit does not specify the induced voltage when the current control unit is saturated. It said current output means, after the position of the plunger is detected by the position detecting means, any one of claims 1 to 10, characterized in that the holding current value of time average of the current according to the current The electromagnetic actuator control device described in 1. The electromagnetic actuator control device according to any one of claims 1 to 11 , wherein the current output means includes current conversion means for converting a current relating to the energization into an alternating current. The current conversion means has a plurality of switching means, and when an abnormality is detected in at least one of the plurality of switching means, the current conversion means operates with another switching means in which the abnormality is not detected. The electromagnetic actuator control device according to claim 12 , wherein: A spring that is connected to the plunger and that drives the plunger in a direction different from the drive by the energization by a restoring force stored by the drive of the plunger by the energization;
The current output means outputs a current in a direction opposite to that during the energization so as to reduce a magnetic force remaining in the plunger when the plunger is driven by the spring. The electromagnetic actuator control device according to 12 or 13 . The plunger is connected to a dog clutch, and controls the engagement of the dog clutch by being driven by the energization.
The electromagnetic actuator control device according to any one of claims 1 to 14 , wherein the position detection unit detects a position of the plunger as a position of the dog clutch. An electromagnetic actuator control method for controlling an electromagnetic actuator comprising a wound coil and a plunger inserted into the coil,
A current output step of driving the plunger by energizing the coil; and
A current control step of performing pulse width modulation control on the energization so as to make the time average of the current related to the energization constant;
An induced voltage specifying step of specifying an induced voltage by driving the plunger;
An inductance calculating step of calculating the inductance of the coil when the identified induced voltage is zero;
A position detecting step of detecting the position of the plunger based on the calculated inductance ;
A temperature detecting step for detecting the temperature of the coil;
A resistance correction step of correcting the resistance of the coil based on the detected temperature;
With
In the induced voltage specifying step, the induced voltage is specified based on the corrected resistance .

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