JP2015233054A - Solenoid control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid control device capable of controlling a current to be supplied to a solenoid with higher accuracy even under a transient state where the current to be supplied to the solenoid does not follow a target value.SOLUTION: The solenoid control device measures a monitor current Iy that flows to a solenoid 101, and controls the monitor current Iy that flows to the solenoid 101, by correcting a duty ratio relating to duty control in such a manner that the monitor current Iy is maintained at a target current Ir every time. Under a normal state where the monitor current Iy is following the target current Ir, the solenoid control device corrects a duty ratio corresponding to the target current Ir on the basis of a ratio of the duty ratio corresponding to the target current Ir and a duty ratio corresponding to the monitor current Iy and under the transient state where the monitor current Iy is not following the target current Ir, the solenoid control device corrects the duty ratio corresponding to the target current Ir on the basis of an estimation coefficient that is determined correspondingly to an electrification amount of the monitor current Iy.

Description

  The present invention relates to a solenoid control device that controls driving while adjusting a current supplied to a solenoid such as a solenoid valve.

  Conventionally, in this type of solenoid control device, the current to the solenoid is controlled by switching between a startup current required at startup and a holding current smaller than the startup current required to maintain the state after startup. It has been known. On the other hand, since the current tends to be less likely to flow as the temperature increases, a technique for calculating the temperature of the solenoid from the flowing current when controlling such a current is also known. For example, Patent Document 1 describes an example of a solenoid control device having such a technique.

  A solenoid control device described in Patent Document 1 is a device that drives and controls a solenoid provided in an electromagnetic valve of a vehicle brake control device, and includes an actuator unit composed of a solenoid and a control unit that controls a current supplied to the solenoid. Is provided. In addition, this apparatus constitutes a feedback control system in which the duty ratio is feedback-corrected by a microcomputer so as to maintain the target current while monitoring the current supplied to the solenoid that is duty controlled. More specifically, the control unit includes a temperature change monitoring unit that monitors the temperature change of the solenoid based on the monitor value of the current supplied to the solenoid, and the monitoring result is taken into the temperature compensation circuit. The temperature compensation circuit sets a gain that compensates the duty ratio that has been mapped so that a larger current flows as the coil temperature increases.

JP 2010-245282 A

  According to the apparatus described in Patent Document 1, the duty ratio is corrected by a gain set corresponding to a temperature change generated in the solenoid, and the current supplied to the solenoid follows the target value.

  By the way, the temperature of the solenoid monitored based on the monitored value of the current can be accurately obtained when the monitored value is stable, while the current supplied to the solenoid is in a transient state in which the target value is not followed. When the monitor value fluctuates, the accuracy may be lowered or may not be obtained in the first place. When the temperature of the solenoid cannot be obtained appropriately, the accuracy of the temperature correction of the duty ratio also decreases, and the followability of the current flowing through the solenoid to the target value also decreases.

  The present invention has been made in view of such circumstances, and its purpose is to provide a higher accuracy for the current supplied to the solenoid even in a transient state where the current supplied to the solenoid does not follow the target value. An object of the present invention is to provide a solenoid control device that can be controlled by the above.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
The solenoid control device that solves the above problems measures the current flowing through the solenoid and corrects the duty ratio for duty control so that the measured current is maintained at the target current each time. A solenoid control device for controlling a flowing current, and when the measured current is in a steady state following the target current, the duty ratio corresponding to the target current and the measured current The duty ratio corresponding to the target current is corrected based on the ratio with the duty ratio, and when the measured current is in a transient state that does not follow the target current, the current supply amount of the measured current is Correspondingly, correcting the duty ratio corresponding to the target current based on a predetermined estimation coefficient And effect.

  The solenoid is known to have a tendency that current does not easily flow when the temperature rises. However, if the solenoid is in a steady state, correction (temperature correction) corresponding to the temperature at that time is performed based on the current measured at that time. It is possible. On the other hand, in the transient state, it is difficult to appropriately perform temperature correction as in the steady state based on the current measured at that time with a large fluctuation. In this respect, according to such a configuration, when in a transient state, a temperature correction is performed on the estimated coefficient that is determined in advance corresponding to the current amount of the measured current, more specifically, the measured current amount. An estimation coefficient that is determined empirically as much as possible is obtained, and the duty ratio is corrected based on the obtained estimation coefficient. As a result, the solenoid control device can control the current supplied to the solenoid with high reliability even in a transient state.

  As a preferred configuration, when in the transient state, the ratio of correcting the duty ratio with respect to the target current in the steady state immediately before entering the transient state is further corrected based on the estimation coefficient.

  According to such a configuration, the temperature of the duty ratio can be appropriately corrected when the steady state changes to the transient state. The estimation coefficient can be further corrected by adding or multiplying the ratio of correcting the duty ratio with respect to the target current.

As a preferred configuration, the amount of energization is the cumulative amount of current that has increased since the transition from the steady state to the transient state.
According to such a configuration, the temperature based on the flowing current can be obtained regardless of the change from the steady state to the transient state by accumulating the amount of current increased when the energization amount is changed from the steady state to the transient state. Correction can be performed continuously.

  As a preferred configuration, the steady state is determined on the basis that a state in which an absolute value of a difference between a target current and a measured current is smaller than a predetermined threshold for determining a tracking mode continues for a predetermined period. .

  According to such a configuration, the steady state is appropriately determined based on the fact that the current difference is smaller than the threshold value for a predetermined period. On the contrary, it can be determined that the state is a transient state because it is not a steady state.

As a preferred configuration, it is determined that the transient state has started based on a change in the target current.
According to such a configuration, the determination of the transient state is not delayed, so that the transient state can be quickly handled.

The block diagram which shows the schematic structure about one Embodiment of a solenoid control apparatus. The flowchart shown about the current correction coefficient acquisition process and current correction coefficient estimation process in the solenoid control device. 3 is a graph showing a relationship among a target current, a monitor current, a steady state temperature correction parameter, a transient state temperature correction parameter, and an actual temperature in the solenoid control device. The graph which shows the temperature rise gradient which can acquire the estimation coefficient corresponding to the temperature of the solenoid in the solenoid control apparatus. The graph which shows the relationship between the target electric current in the same solenoid control apparatus, a monitor electric current, and a duty ratio. The graph which shows the relationship between a monitor current and a duty ratio about each of the steady state in the solenoid control apparatus, and a transient state.

An embodiment embodying a solenoid control device will be described with reference to FIGS.
An overview of the present embodiment will be described with reference to FIG.
The solenoid control device according to the present embodiment is a brake control device including, for example, a control unit (ECU) integrated actuator structure, and is configured as a device that controls driving of a solenoid provided in a solenoid valve. The solenoid control device includes an actuator unit 100 and a control unit (ECU) 200 that controls driving of the actuator unit 100, and is connected to a battery 300 that supplies power. In the present embodiment, the solenoid 101 of the electromagnetic valve that constitutes the brake control device is the control target.

The battery 300 is, for example, a battery mounted on a vehicle, and its voltage usually changes depending on the electric load of the vehicle, the operating state of the engine, and the like.
On the other hand, as is well known, the solenoid 101 that constitutes the actuator unit 100 is an actuator in which a movable iron core is installed in a coil, and this movable iron core is linearly moved by an electromagnetic force generated by passing a current through the coil. And although the said solenoid valve driven by such a solenoid 101 requires a big current as a starting current at the time of starting, after starting once, the holding current which is a current smaller than this starting current is supplied. Thus, the driving state can be maintained. For this reason, the current supplied to the solenoid 101 is switched from the starting current to the holding current in accordance with the driving state of the solenoid valve. In the present embodiment, such control of the supply current to the solenoid 101 is performed through duty control using PWM (pulse width modulation) by a control unit (ECU) 200 described below.

  The control unit (ECU) 200 constituting the control unit (ECU) integrated actuator structure includes a solenoid relay 210 that can cut off power supply from the battery 300 to the solenoid 101. Further, the control unit (ECU) 200 equivalently has a configuration illustrated in FIG. 1, a microcomputer 220 that executes current feedback control and interrupt processing, and a solenoid based on a duty ratio command generated through the microcomputer 220. And an output IC 230 that monitors the current flowing in the solenoid 101 while driving the solenoid 101.

  Among these, in the microcomputer 220, first, when a user command according to the depression amount, the depression speed, or the like is input by depressing the brake pedal, the target current to be supplied to the solenoid 101 according to the user command. Ir is set by the target current setting unit 221. Based on the set target current Ir, the duty ratio when the solenoid 101 is PWM-driven is calculated through the current-duty conversion map 222. From the current-duty (Duty) conversion map 222, the target duty ratio Dr when the solenoid is at the reference temperature and the applied voltage is the reference voltage is calculated.

  Referring to FIG. 6 in detail, the current-duty (Duty) conversion map 222 shows the relationship between the actual solenoid current and the duty ratio when the solenoid temperature is 25 ° C. and the applied voltage is DC 12 V, for example. Has been. As shown in the graph labeled steady state, the correlation between the actual current and the duty ratio is maintained in the steady state where the actual current is stable. Identified. In the current-duty (Duty) conversion map 222, data in a steady state is set, and the target duty ratio Dr when the actual current is the target current Ir is calculated as a map. . In addition, with respect to the temperature change generated in the solenoid, a temperature change monitoring unit 223a, which will be described later, corrects the temperature change, so-called temperature correction. In the transient state in which the temperature of the solenoid fluctuates, the relationship between the actual current and the duty ratio fluctuates between the graphs indicated by the high temperature graph and the low temperature graph in FIG. 6 (the slope of the graph changes). Therefore, the correlation between the actual current and the duty ratio is not maintained. For this reason, it has been difficult to perform temperature correction with high accuracy with respect to a temperature change generated in the solenoid with respect to the duty ratio calculated on the map. Therefore, in this embodiment, the temperature change monitoring unit 223a can perform temperature correction with high accuracy even in a transient state.

  The temperature change monitoring unit 223a monitors the temperature change of the solenoid 101 based on the monitor value (monitor current Iy) of the current supplied to the solenoid 101. The temperature change monitoring unit 223a corrects the target duty ratio Dr calculated through the map so that a larger current flows as the coil temperature becomes higher, based on a phenomenon that current becomes difficult to flow as the coil (solenoid) temperature becomes higher. The correction coefficient is set in the temperature correction circuit (KT) 223b. Thus, the temperature correction circuit 223b in which the correction coefficient is set compensates the target duty ratio Dr calculated through the map based on the set correction coefficient. That is, the target duty ratio Dr is corrected based on a correction coefficient for performing temperature correction required according to the temperature change of the solenoid. Then, an output duty ratio Do obtained by feedback-correcting the temperature-corrected duty ratio is output from the microcomputer 220 as a drive command for the output IC 230.

  When a signal indicating the output duty ratio Do is output as a drive command from the microcomputer 220 in this way, the output IC 230 generates a drive pulse corresponding to the output duty ratio Do through the PWM drive unit 231, and a transistor is generated by the generated drive pulse. The (P-channel FET) 232 is turned on / off. As a result, the battery voltage supplied via the solenoid relay 210 is applied to the solenoid 101 as a duty signal that is pulsed in synchronization with the on / off timing of the transistor 232, and the output duty ratio of the duty signal. A current (average current) corresponding to Do is supplied to the solenoid 101.

  On the other hand, in the control unit (ECU) 200, the current supplied to the solenoid 101 flows to the ground (GND) via the other transistor (N-channel FET) 233 of the output IC 230. The transistor 233 takes in the current supplied to the solenoid 101 as a voltage value proportional to its internal resistance. The captured voltage is converted into a current value via the voltage / current conversion unit 234, and the converted current is quantized by the A / D conversion unit 235, and at the same time through the digital filter 236 (fixed time). Calculate the moving average value for each period. The obtained moving average value of the monitor current is input to the microcomputer 220 as a monitor current Iy that is a monitor value of the current supplied to the solenoid 101.

  In the microcomputer 220, the target current Idr monitored by the target current monitoring unit 224 corresponding to the input monitor current Iy and the target duty ratio Dr calculated through the previous current-duty conversion map 222 is calculated. The value is compared. Based on this comparison, the microcomputer 220 feedback-corrects the temperature-corrected duty ratio value through the known PI controller 228 so that the monitor current Iy matches the target current Idr at an early stage. By configuring such a feedback control system with the microcomputer 220 and the output IC 230, the value of the current (monitor current Iy) supplied to the solenoid 101 is controlled so as to follow the target current Ir set based on the user command. Will come to be. In the feedback control system, the starting current and the holding current are automatically switched through the target current setting unit 221.

  Further, in such a known feedback control system, there are a steady state in which the output value follows the target value and a transient state in which the output value does not follow. In the present embodiment, the monitor current Iy follows the target current Ir, the state where the monitor current Iy is stable is a steady state, and the monitor current Iy does not follow the target current Ir. The state in which the monitor current Iy fluctuates is a transient state. That is, in the steady state, the difference between the target current Ir and the monitor current Iy is small, while in the transient state, the difference between the target current Ir and the monitor current Iy is large.

  In addition, an interrupt processing unit 229 is provided in the feedback path of the feedback control system configured in the microcomputer 220 via a pseudo switch 227, and battery voltage fluctuations are periodically monitored through the interrupt processing unit 229. Then, the current supplied to the solenoid 101 is estimated from the monitoring result, and further necessary correction is added to the duty ratio that is feedback-corrected based on the estimated current. Note that such monitoring of the battery voltage by the interrupt processing unit 229 is performed via the solenoid relay 210. As a result, even when the voltage of the battery 300 serving as the driving power source of the solenoid 101 changes depending on the electric load of the vehicle, the operating state of the engine, etc., the current that can maintain the driving state at a minimum is maintained. Keep the value.

  The temperature change monitoring unit 223a calculates a coefficient used in the steady state among the state determination unit 223c that determines whether the state is a steady state or a transient state, and a correction coefficient for correcting the temperature of the target duty ratio Dr. A steady state correction coefficient calculation unit 223d that performs the transient state correction coefficient calculation unit 223e that calculates a coefficient used in the transient state.

  The state determination unit 223c determines whether the state is a steady state or a transient state based on a comparison between the “absolute value of the difference between the target current Ir and the monitor current Iy” and the “following determination threshold value”. . The “follow-up determination threshold value” is a threshold value for determining the follow-up mode from the absolute value of the difference between the target current Ir and the monitor current Iy. For example, a value such as “6 mA” It is set based on the resolution. The temperature change monitoring unit 223a determines that the state is “steady state” on condition that a state where “the absolute value of the difference between the target current Ir and the monitor current Iy” is smaller than the “following determination threshold value” continues for a predetermined period or longer. On the other hand, if it is not “steady state”, it is determined that it is “transient state”. That is, the “transient state” is a state when “the absolute value of the difference between the target current Ir and the monitor current Iy” is equal to or greater than the “following determination threshold value”. The predetermined period used for the determination of the steady state is, for example, “4 msec”, and is set based on experience and experiment, the response characteristics of the solenoid 101, the sampling period of the monitor current Iy, and the like. Note that the change in state from the steady state to the transient state, that is, the start of the transient state, is determined to have occurred due to the change in the target current Ir due to the change in the user command.

  The steady state correction coefficient calculation unit 223d performs a steady state correction coefficient calculation process, and calculates a correction coefficient for the steady state based on the ratio between the target duty ratio Dr and the output duty ratio Do. The correction coefficient for the steady state is a ratio between the target duty ratio Dr corresponding to the target current Ir and the output duty ratio Do corresponding to the monitor current Iy, and is calculated as “output duty ratio Do / target duty ratio Dr”. Is done. This correction coefficient is a feedforward coefficient when in a steady state. Since the target duty ratio Dr corrected by the correction coefficient approaches the output duty ratio Do, it can be said that the correction coefficient is learned as a feedforward coefficient. This correction coefficient corrects the target duty ratio Dr based on the feedback correction value that has changed due to the influence of the temperature change, and thus also corrects the temperature. The correction coefficient is subjected to filter processing (steady state correction coefficient calculation filter) so as to stabilize the system, and is updated and stored in the temperature change monitoring unit 223a. Note that this correction coefficient requires some time to be calculated because the output duty ratio Do is used for the calculation. Hereinafter, this correction coefficient is referred to as a steady-state correction coefficient.

  As shown in FIG. 3, the steady-state correction coefficient calculation unit 223d calculates a correction coefficient for the steady state when in a steady state such as between time t3 and t4, while in a transient state such as between time t1 and t2. Is maintained at the value when the value changes from the steady state to the transient state. For example, even if the temperature of the solenoid rises during the transitional state from time t1 to time t2, and the current does not flow easily, the steady state correction coefficient is not changed. Therefore, the output duty ratio Do is used when the steady state correction coefficient is used. The accuracy of the temperature correction at is reduced.

  As shown in FIG. 4, the transient state correction coefficient calculation unit 223e performs a transient state correction history number calculation process, and estimates the correction coefficient for the transient state based on the monitor current Iy and the temperature increase gradient PR. To do. The temperature increase gradient PR is, for example, a map, and indicates a relationship between an amount of current actually measured by flowing a current through the solenoid 101 in advance and an estimation coefficient. The transient state correction coefficient calculation unit 223e obtains a corresponding estimation coefficient by applying the accumulated amount of the monitor current Iy that has increased since the transition from the steady state to the transient state to the temperature increase gradient PR. Since the estimation coefficient acquired in this way is an estimation coefficient for the amount of current increased since the transition to the transient state, the transient state correction coefficient calculation unit 223e uses the acquired estimation coefficient as the correction coefficient for the previous steady state. The correction coefficient for the transient state is estimated by adding. Since the estimated correction coefficient is estimated using the temperature increase gradient PR set based on the influence of the temperature change, temperature correction is performed. Hereinafter, the estimated correction coefficient is referred to as a transient correction coefficient.

  As shown in FIG. 3, the transient state correction coefficient calculation unit 223e acquires an estimation coefficient from the temperature increase gradient PR in a transient state such as time t1 to t2, and uses the estimated coefficient as a steady state correction coefficient at time t1. The correction coefficient for the transient state is estimated by adding. Thereby, at time t1, continuity with the correction coefficient for the steady state is maintained. Further, the correction coefficient for the transient state is continuously changed and the target duty ratio Dr is corrected so as to be continuously changed at the times t1 to t2 in which the correction coefficient for the steady state is not updated. When the transient state changes to the steady state (time t2), the transient state correction coefficient is set in the temperature correction circuit 223b until the steady state correction coefficient is calculated (time t3). When there is no steady state immediately before the power is turned on, a predetermined initial value can be used as the steady state correction coefficient.

The operation of the temperature change monitoring unit 223a will be described with reference to FIGS. This temperature correction process is appropriately executed at a predetermined processing cycle or the like.
When the temperature correction process is started, the temperature change monitoring unit 223a determines whether or not it is in a steady state (step S10 in FIG. 2). As shown in FIG. 3, during the period from time t1 to time t2, the absolute value of the difference between the target current Ir and the monitor current Iy is greater than or equal to the follow-up determination threshold value, so that it is determined as a transient state. On the other hand, from time t3 to time t4, the absolute value of the difference between the target current Ir and the monitor current Iy is smaller than the follow-up determination threshold value, so that it is determined as a steady state.

  When it is determined that it is in a steady state (YES in step S10 in FIG. 2), the temperature change monitoring unit 223a performs steady state correction coefficient calculation processing (step S11 in FIG. 2) and performs steady state correction coefficient calculation filter processing. This is performed (step S12 in FIG. 2). In the steady-state correction coefficient calculation processing, the steady-state correction coefficient is calculated by “output duty ratio Do / target duty ratio Dr”, and at a value that maintains the stability of the system by the steady-state correction coefficient calculation filter processing. Adjusted. Then, the corrected target duty ratio Dr output from the temperature correction circuit 223b in which the correction coefficient for the steady state is set is output from the temperature correction circuit 223b as a feedforward value to perform feedforward processing ( Step S13 in FIG.

  On the other hand, if it is determined that the state is a transient state (NO in step S10 of FIG. 2), the temperature change monitoring unit 223a performs a transient state correction coefficient calculation process (step S14 of FIG. 2). The correction coefficient for the transient state is the correction coefficient for the steady state immediately before the estimated coefficient obtained by applying the increased amount of current after the transition to the temperature rise gradient PR is changed from the steady state to the transient state. To be estimated. Then, the feedforward process is performed by outputting the target duty ratio Dr corrected by the correction coefficient for the transient state as a feedforward value from the temperature correction circuit 223b (step S13 in FIG. 2).

Duty control is performed by feedback-correcting the feedforward value output in this way and creating the output duty ratio Do.
The operation of the present embodiment will be described with reference to FIGS.

  When the target current Ir flowing through the solenoid 101 is set, the difference from the monitor current Iy is large, so that a large value is fed back to the target duty ratio Dr, and the output duty ratio Do increases rapidly. As the monitor current Iy increases, the difference between the target current Idr and the monitor current Iy gradually decreases, so that the fluctuation of the output duty ratio Do settles, and the monitor current Iy follows the target current Ir.

  Conventionally, in the transient state, the difference between the target current Ir and the monitor current Iy is corrected by feedback correction. After that, the temperature change monitoring unit 223a performs the correction value of the feedback correction (target duty ratio Dr. Based on the difference from the output duty ratio Do), a steady-state correction coefficient is calculated and set in the temperature correction circuit 223b. As a result, the feedforward correction coefficient is updated. That is, conventionally, since the correction coefficient for correcting the temperature is not updated until the steady state is reached, the accuracy of the temperature correction is not high.

  On the other hand, in the present embodiment, in the transient state, the difference between the target current Ir and the monitor current Iy is feedback-corrected as described above, and the transient-state correction coefficient used for the feedforward correction is also a temperature change monitoring unit. It is estimated by 223a and updated sequentially. That is, in the transient state, the target duty ratio Dr is feedback-corrected and also temperature-corrected by the feedforward transient state correction coefficient, so that temperature correction is performed with high accuracy even in the transient state. It becomes like this. Further, after reaching the steady state, the correction coefficient for the steady state is calculated, but since the feedback correction value (difference between the target duty ratio Dr and the output duty ratio Do) is small, the correction for the transient state is performed. It is also expected that the difference from the coefficient is reduced and good continuity is obtained.

  According to this embodiment, even in a transient state where the monitor current Iy supplied to the solenoid 101 does not follow the target current Ir, the solenoid that can control the monitor current Iy supplied to the solenoid 101 with higher accuracy. A control device can be provided. That is, the monitor current Iy supplied to the solenoid 101 in both the steady state and the transient state is controlled with high accuracy without distinction between the two states.

As described above, the solenoid control device according to the present embodiment has the effects listed below.
(1) The solenoid 101 is known to have a tendency that current does not easily flow when the temperature increases. However, if the solenoid 101 is in a steady state, the correction corresponding to the temperature at that time is based on the monitor current Iy measured at that time. (Temperature correction) can be performed. On the other hand, in the transient state, it is difficult to appropriately perform temperature correction similarly to the steady state based on the monitor current Iy measured at that time with a large fluctuation. In this regard, according to the configuration of the present embodiment, when in a transient state, an estimation coefficient that is determined in advance corresponding to the measured amount of the monitor current Iy, more specifically, the measured monitor current Iy. An estimated coefficient that is empirically obtained to correct the temperature for the current amount is obtained, and the duty ratio is corrected based on the obtained estimated coefficient. As a result, the solenoid control device can control the current supplied to the solenoid 101 with high reliability even in a transient state.

  (2) When changing from a steady state to a transient state, temperature correction of the duty ratio can be performed appropriately. It should be noted that the ratio of correcting the duty ratio with respect to the target current can be further corrected by adding or multiplying the estimation coefficient.

  (3) The temperature based on the monitor current Iy can be obtained even when the current amount of the monitor current Iy is accumulated from the steady state to the transient state by accumulating the amount of current increased after the change from the steady state to the transient state. Correction can be performed continuously.

  (4) Based on the fact that the current difference is smaller than the follow-up determination threshold for a predetermined period, it is appropriately determined that it is in a steady state. On the contrary, it can be determined that the state is a transient state because it is not a steady state.

  (5) Since it is determined that the transient state has started based on the change in the target current Ir, the determination of the transient state is not delayed, so that the transient state can be quickly handled.

(Other embodiments)
In addition, the said embodiment can also be implemented with the following aspects.
-In above-mentioned embodiment, although illustrated about the case where there was one solenoid 101, it is not restricted to this, A plurality may be sufficient as a solenoid. Thereby, the electric current which flows into a plurality of solenoids can be controlled suitably.

  In the above-described embodiment, the case where the interrupt processing unit 229 is provided to perform feedback correction according to the battery voltage is illustrated, but the present invention is not limited thereto, and the interrupt processing unit may not be provided. Even if there is no interrupt processing unit, the influence of the battery voltage is corrected by the PI controller. This increases the degree of freedom in designing the control system.

  In the above embodiment, the case where feedback correction is performed by the PI controller 228 is illustrated, but the present invention is not limited thereto, and feedback correction may be performed by a PID controller or other controllers.

  As one of the other controllers, when the monitor current is unreliable, the current value indicated by the monitor current is classified into three classes, “Small”, “Medium”, and “Large”, and the correction amount determined for each class A controller that performs feedback correction is exemplified. At this time, the correction amount for correcting the duty ratio is increased in the order of “small”, “medium”, and “large” classes.

These increase the degree of freedom in designing the solenoid control device.
In the above embodiment, the case where the transient state is started when the target current Ir changes is illustrated, but the determination may be made based on the difference between the target current and the monitor current being equal to or greater than the state determination threshold. As a result, the degree of freedom of the determination condition as to whether the steady state or the transient state is increased.

  In the above-described embodiment, the follow-up determination threshold value is exemplified as a positive number. However, the present invention is not limited thereto, and the follow-up determination threshold value is a pair of threshold values indicating an upper limit value and a lower limit value of a range determined to be following. There may be. In this case, the difference between the target current and the monitor current need not be an absolute value. As a result, the degree of design freedom regarding the determination of the follow-up mode is increased.

  In the above embodiment, the case where the correction coefficient for the transient state is estimated by adding the estimation coefficient acquired from the temperature rise gradient PR to the correction coefficient for the immediately previous steady state is illustrated. It may be calculated by adding the correction coefficient to the state correction coefficient. As a result, the degree of freedom in design related to the calculation of the correction coefficient for the transient state is increased.

  In the above-described embodiment, the case where the monitor current Iy is used for the determination of the steady state and the transient state is illustrated. However, the present invention is not limited to this, and the solenoid current is applied to the solenoid as a condition for determining whether it is the steady state or the transient state. The magnitude of the voltage fluctuation may be used. For example, when the voltage fluctuation is large, it is determined as a transient state, and when the voltage fluctuation is small, it is determined as a steady state. Thereby, the determination conditions of a steady state and a transient state can be made into a suitable condition.

  In the above embodiment, the case where the solenoid control device is applied to a brake control device including an actuator structure integrated with a control unit (ECU) is illustrated. This configuration can be applied. Further, the application target is not limited to the control unit (ECU) integrated actuator structure.

  DESCRIPTION OF SYMBOLS 100 ... Actuator part, 101 ... Solenoid, 200 ... Control part, 210 ... Solenoid relay, 220 ... Microcomputer, 221 ... Target current setting part, 223a ... Temperature change monitoring part, 223b ... Temperature correction circuit, 223c ... State judgment part, 223d ... state correction coefficient calculation unit, 223e ... transient state correction coefficient calculation unit, 224 ... target current monitoring unit, 227 ... switch, 228 ... PI controller, 229 ... interrupt processing unit, 230 ... output IC, 231 ... PWM drive unit, 232, 233 ... transistor, 234 ... voltage / current converter, 235 ... A / D converter, 236 ... digital filter, 300 ... battery, Do ... output duty ratio, Dr ... target duty ratio, Ir ... target current, Iy ... Monitor current, PR: temperature rise gradient, t1, t2, t3, t4: time, Idr: target current.

Claims (5)

The solenoid control device controls the current flowing through the solenoid by measuring the current flowing through the solenoid and correcting the duty ratio applied to the duty control so that the measured current is maintained at the target current each time. And
When the measured current is in a steady state following the target current, the target is set based on the ratio of the duty ratio corresponding to the target current and the duty ratio corresponding to the measured current. Correct the duty ratio corresponding to the current,
When the measured current is in a transient state that does not follow the target current, the duty corresponding to the target current is based on an estimation coefficient that is determined in advance corresponding to the energization amount of the measured current. A solenoid control device characterized by correcting the ratio. 2. The solenoid control device according to claim 1, wherein when in the transient state, the ratio of correcting the duty ratio with respect to the target current in a steady state immediately before entering the transient state is further corrected based on the estimation coefficient. The solenoid control device according to claim 1 or 2, wherein the energization amount is a cumulative amount of current that has increased since a change from a steady state to a transient state. The steady state is determined on the basis that a state in which an absolute value of a difference between a target current and a measured current is smaller than a predetermined threshold for determining a tracking mode continues for a predetermined period. 4. The solenoid control device according to claim 3. The solenoid control device according to any one of claims 1 to 4, wherein the transient state is determined based on a change in the target current.

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