JP4678476B2 - Electric motor control device - Google Patents

Description

  The present invention relates to a control device that performs synchronous control of a plurality of motors having different characteristics and / or loads, and particularly relates to a motor control device that can simplify arithmetic processing for control.

  Conventionally, regarding a control device for a vehicle opening / closing body that can be used for a hood or a roof panel of a convertible vehicle, two electric motors having the same characteristics and the same load are arranged on the left and right sides, and the speeds of these two electric motors are synchronized. There is known a control device that performs control. This control device includes a rotation sensor that generates a pulse signal synchronized with the rotation of the motors in order to synchronously control the speeds of the two motors, and the current position and current position of the two motors are determined by signals from the rotation sensors. Calculate the speed. Then, a target position after a unit time is calculated from the average position of the current positions of the two motors and a predetermined target speed of the motors, and a unit time after the current positions and the current speeds of the two motors. Calculate the predicted position of each motor. Next, the target position after the unit time and the predicted position of each motor are compared to calculate the control position of each motor after the unit time, and the speed control of each motor is performed accordingly (for example, Patent Document 1). reference).

JP 2001-119976 A (page 2-3, FIG. 1)

  However, in such a conventional control device, it is suitable for synchronous control of a plurality of motors having the same characteristics and load. However, when synchronous control of a plurality of motors having different characteristics or loads is performed. Since it is necessary to perform different arithmetic processing depending on each electric motor for the calculation of the predicted position, speed control, etc., the calculation burden of the control device increases in proportion to the number of electric motors. Therefore, when performing synchronous control of a large number of motors having different characteristics and / or loads, it is required to use a high-performance arithmetic processing unit, which causes a problem of cost increase.

  Normally, in order to prevent the motor from causing hunting, a certain allowable range is provided before and after the target position, and if the position of the motor is controlled within the allowable range, finer speed control is performed. The control is performed so as to maintain the position of the electric motor within the allowable range. However, when such control is performed in a plurality of electric motors having different characteristics and / or loads, when the control state becomes stable, the operation speed in that state is higher than the upper limit operation speed of the motor. Depending on how much room is available, a motor with a margin will be stable on the leading side, and a motor with no margin will be stable on the lagging side. There may be a difference in position within the allowable range. In addition, there is a difference in operation stop timing due to such a difference in the position of the motor, but even if not all the motors can be stopped at the same time, the motor can It may be necessary to control to stop in a predetermined order. In these cases, it is necessary to perform control for adjusting the position difference of each motor within the allowable range and the stop order based on such position difference.

  The present invention has been made in view of the above problems, and its purpose is to simplify arithmetic processing for control when performing synchronous control of a plurality of motors having different characteristics and / or loads. It is possible to reduce the cost of the apparatus, and to control the motor to adjust the degree of advance or delay within the allowable range of control based on the characteristics and load of each motor or the operation request for the motor. The control device is provided.

The first characteristic feature of the motor control apparatus according to the present invention for achieving the above object, a detection unit for outputting it as actual operation amount information by detecting the actual operation amount of the electric motor, the plurality of electric motors By multiplying the theoretical operation amount at an arbitrary point in time, the actual operation amount information of each motor is multiplied by a conversion coefficient that takes a value such that the multiplication results coincide with each other. Based on the reference operation amount information of each electric motor, the reference operation amount at any time of the plurality of electric motors is within a certain allowable range based on the conversion unit that converts the reference operation amount information to output and the reference operation amount information of each electric motor. And a control unit that controls the operation of each motor, and an adjustment coefficient that adjusts the degree of advance or delay of the reference operation amount of each motor within the allowable range in the control unit. And that the adjustment unit, in that it comprises a.

  According to this first feature configuration, the operation control of a plurality of motors having one or both of different characteristics and loads is performed based on a unified scale called the reference operation amount, so that the operations of a plurality of motors having the same characteristics and loads are performed. The calculation process can be the same as that for the control, and the calculation process for the control can be simplified and the cost of the apparatus can be reduced. In addition, in order to prevent the motor from causing hunting, when the control unit performs control such that the operation amount of each motor to be controlled falls within a certain allowable range, each motor generated within the allowable range Can be adjusted appropriately.

  A second characteristic configuration of the motor control device according to the present invention is that the conversion coefficient is a constant determined for each motor based on a ratio of theoretical operation amounts of the plurality of motors.

  According to the second feature configuration, the conversion coefficient used in the conversion unit can be determined in advance at the design stage of the apparatus.

  According to a third characteristic configuration of the motor control device according to the present invention, the adjustment coefficient is a request for delaying a difference between a theoretical operation speed and an upper limit operation speed of each of the plurality of motors and an operation stop. The value is set based on one or both of the heights.

  According to the third feature configuration, in order to prevent the electric motor from causing hunting, when the control unit performs control such that the operation amount of each electric motor to be controlled falls within a certain allowable range, The advance or delay of each motor that occurs within the allowable range is adjusted based on the height of the request to delay the operation stop of each motor, and the motor that is desired to delay the operation stop among the plurality of motors is stopped later, or at least others It is possible to perform control to stop simultaneously with the motor. Further, the advance or delay of each motor that occurs within the allowable range is adjusted based on the difference between the theoretical operation speed of each motor and the upper limit operation speed according to the characteristics of each motor, and the advance of each motor. Alternatively, the difference in delay can be reduced.

  The fourth characteristic configuration of the motor control device according to the present invention is that a period of time during which the operation of the operating motor is not stopped or the operation of the stopped motor is not started is defined as one control region, and a plurality of operating units are operated for each control region. The point is that the operation is controlled for the electric motor.

  According to the fourth feature configuration, even when there are some of the plurality of electric motors having different operation start timing and operation stop timing, the above-described first to third are intended for the plurality of operating motors. The synchronous control can be performed by the same simple process as in the case of the feature configuration.

  Hereinafter, an embodiment in which the motor control device according to the present invention is applied to synchronous control of a drive motor for a seat 1 in a welfare vehicle 2 that can swing the seat 1 out of the vehicle or store it in the vehicle interior. Will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating a movement mode of the seat 1 of the welfare vehicle 2 according to the present embodiment, and FIG. 2 is a functional block diagram of the motor control device according to the present embodiment.

  As shown in FIG. 1, the seat 1 of the welfare vehicle 2 according to this embodiment hits a door, a vehicle body, or the like by simultaneously operating in three directions of a rotation direction A, a front / rear slide direction B, and an inner / outer slide direction C. The vehicle can be swung out to the outside of the vehicle or stored inside the vehicle through an appropriate locus E having no gap. Thus, in order to move the seat 1 simultaneously at an appropriate speed in each of the three directions, in the present embodiment, as shown in FIG. 2, the first motor M1 and the second motor are used for each operation in the three directions. Three electric motors M2 and a third electric motor M3 are provided. That is, the first motor M1 is responsible for the operation of the seat 1 in the rotational direction A, the second motor M2 is the forward / backward sliding direction B, and the third motor M3 is the inner / outer sliding direction C. Make it work.

  The first electric motor M1, the second electric motor M2, and the third electric motor M3 have different operation amounts from the start to the end of the operation when the seat 1 is moved out or stored, and the operation speed and load during the operation are also different. That is, the first electric motor M1, the second electric motor M2, and the third electric motor M3 have different loads, and electric motors having different characteristics are used accordingly.

  Further, as shown in FIG. 2, the first electric motor M1, the second electric motor M2, and the third electric motor M3 have a first sensor S1 that outputs a pulse signal in accordance with an operation amount (here, an amount of rotation), and a first sensor S1. The number of pulse signals output from the two sensors S2 and the third sensor S3 and the first sensor S1, the second sensor S2, and the third sensor S3 are integrated to calculate the actual number of pulses, and the actual number of pulses is calculated. A first integrator I1, a second integrator I2, and a third integrator I3 that output information are provided. This “actual pulse number” represents the actual operation amount from the start of operation of each of the motors M1 to M3 to the present time, and corresponds to the “actual operation amount” in the present invention. Therefore, “actual pulse number information” corresponds to “actual operation amount information” in the present invention. In the present embodiment, the first sensor S1, the second sensor S2, the third sensor S3, the first integrator I1, the second integrator I2, and the third integrator I3 constitute the detection unit 3. Yes. In the following, the total operation amount, that is, the total number of pulses of the electric motors M1 to M3 from the start to the end of the operation when the seat 1 is moved out or stored, the first electric motor M1 is 250 pulses, the second electric motor M2 is 500 pulses, The case where the third electric motor M3 has 1000 pulses will be described as an example. Here, in order to simplify the description, the total number of pulses of each of the motors M1 to M3 is set to a relatively simple number of pulses, and the ratio of the total operation amount between the motors M1 to M3 is as simple as 1: 2: 4. I try to be something.

  The actual pulse number information output from the first integrator I1, the second integrator I2, and the third integrator I3 is input to the conversion unit 4. And in the conversion part 4, it converts so that the theoretical pulse number in the arbitrary time of the 1st electric motor M1, the 2nd electric motor M2, and the 3rd electric motor M3 may correspond with respect to the actual pulse number information of each electric motor M1-M3. Each of the conversion coefficients a1, a2, and a3 is multiplied to convert the information into reference pulse number information of each of the electric motors M1 to M3 and output the information. This “reference pulse number information” corresponds to “reference operation amount information” in the present invention. Here, the “theoretical pulse number” is a pulse at each time point of each of the first motor M1, the second motor M2, and the third motor M3 when each of the motors M1 to M3 performs an ideal operation as designed. The number of theoretical pulses corresponds to the “theoretical operation amount” in the present invention. The conversion coefficients a1, a2, and a3 are multiplied by the respective theoretical pulse numbers at arbitrary points in time of the first electric motor M1, the second electric motor M2, and the third electric motor M3. It is a coefficient that takes such a value. Therefore, in the present embodiment, the conversion coefficients a1 to a3 are constants determined based on the ratio of the number of theoretical pulses (theoretical operation amount) of the electric motors M1 to M3 to be controlled. That is, when the ratio of the total number of pulses of the first electric motor M1, the second electric motor M2, and the third electric motor M3 is 1: 2: 4, and all the electric motors M1 to M3 perform an ideal operation as designed. Since the ratio of the number of pulses of each of the motors M1 to M3 does not change at any time during operation, the ratio of the theoretical number of pulses is 1: 2: 4 at all times during the operation of each of the motors M1 to M3. . Therefore, if the ratio of the conversion coefficients a1, a2, and a3 is set to the inverse ratio 4: 2: 1 of the ratio 1: 2: 4 of the theoretical pulse numbers of the electric motors M1 to M3, any electric motor M1 to M3 The results obtained by multiplying the respective theoretical pulse numbers at the time by the conversion coefficients a1, a2, and a3 coincide with each other. Therefore, here, the conversion coefficients are a1 = 4, a2 = 2, and a3 = 1. These conversion coefficients a1 to a3 are stored in the storage unit 5 and are read out during the conversion process in the conversion unit 4.

  The conversion process from the actual pulse number information of each of the motors M1 to M3 in the conversion unit 4 to the reference pulse number information will be specifically described with reference to FIG. In FIG. 3, the three axes of the M1, M2, and M3 axes, which are the axes representing the actual pulse numbers of the first electric motor M1, the second electric motor M2, and the third electric motor M3, are set as the horizontal axis (x axis). The axis representing the reference pulse number of the first electric motor M1, the second electric motor M2 and the third electric motor M3 is taken as the vertical axis (y-axis), and the actual pulse number information of each electric motor M1 to M3 is referred to by the conversion coefficients a1, a2 and a3. It is a graph showing the conversion function at the time of converting into pulse number information. As shown in this figure, if the actual pulse number of each motor M1 to M3 is x and the reference pulse number of each motor M1 to M3 is y, the conversion functions of each motor M1 to M3 are “y = a1x”, “ y = a2x ”and“ y = a3x ”. Here, since the conversion coefficients are a1 = 4, a2 = 2, and a3 = 1, the conversion function to the reference pulse number information in the conversion unit 4 is specifically “y = 4x ”,“ y = 2x ”for the second motor M2, and“ y = x ”for the third motor M3. For example, when the actual pulse number of the first electric motor M1 at a certain time is “155”, the actual pulse number of the second electric motor M2 is “300”, and the actual pulse number of the third electric motor M3 is “580”, the conversion unit 4 The converted reference pulse numbers of the electric motors M1 to M3 are “620” for the first electric motor M1, “600” for the second electric motor M2, and “580” for the third electric motor M3. Here, when all the motors M1 to M3 perform an ideal operation as designed, that is, when the actual pulse number of each motor M1 to M3 is equal to the theoretical pulse number, the reference of all the motors M1 to M3 Since the number of pulses matches, the difference in the number of reference pulses of each of the electric motors M1 to M3 can be considered as a control error. Therefore, by converting the actual pulse number information of each of the motors M1 to M3 into the reference pulse number information in this way, the control unit 6 can easily control errors by only comparing the reference pulse number which is a unified measure. It is possible to detect the advance or delay of the reference pulse number.

  In the present embodiment, the control unit 6 compares the reference pulse number information of each of the motors M1 to M3, reduces the speed of the motor in which the reference pulse number is advanced, and determines the speed of the motor in which the reference pulse number is delayed. Control to increase. At this time, if the control of changing the speed of the motor is performed until the advance or delay of the reference pulse number is slight, the motor may cause hunting. Therefore, as shown in FIG. If a certain allowable range R is provided for the advance or delay of the reference pulse number, and the position of each of the motors M1 to M3 is controlled within the allowable range R, no further fine speed control is performed, and the allowable range R Control is performed so as to maintain the positions of the electric motors M1 to M3. Accordingly, each of the electric motors M1 to M3 may cause the reference pulse number to advance or delay within the allowable range R.

  The adjustment unit 7 adjusts the adjustment coefficients α1, α2, and α3 for adjusting the degree of advance or delay of the reference pulse numbers of the electric motors M1 to M3 within the allowable range R in the control unit 6 in the conversion unit 4. A process of multiplying the conversion coefficients a1, a2 and a3 of the electric motors M1 to M3 is performed. In the present embodiment, as shown in FIG. 2, since the reference pulse number information after conversion by the conversion unit 4 is input to the adjustment unit 7, the adjustment unit 7 receives the input reference pulses of the motors M <b> 1 to M <b> 3. By multiplying the number information by adjustment coefficients α1, α2, and α3, the adjusted reference pulse number information (hereinafter simply referred to as “adjusted reference pulse number information”) of each of the motors M1 to M3 is controlled. 6 is output. As a result, the conversion coefficients a1, a2 and a3 are multiplied by the adjustment coefficients α1, α2 and α3. Note that the functional configuration of the adjustment unit 7 is not limited to that shown in FIG. 2, and as a result, adjustment is performed by multiplying the conversion coefficients a1, a2, and a3 by the adjustment coefficients α1, α2, and α3. Therefore, for example, the actual pulse number information before conversion by the conversion unit 4 is first multiplied by the adjustment coefficients α1, α2, and α3, and the result is converted by the conversion unit 4 at the conversion coefficients a1, a2, and a3. The adjustment unit 7 may be provided in the conversion unit 4 and the actual pulse number information may be converted by a coefficient obtained by multiplying the conversion coefficients a1, a2, and a3 by the adjustment coefficients α1, α2, and α3 in advance. Is possible.

  The adjustment processing of the degree of advance or delay of the reference pulse number of each of the motors M1 to M3 in the adjustment unit 7 will be specifically described with reference to FIG. In FIG. 5, the three axes of the M1 axis, M2 axis, and M3 axis, which are axes representing the actual pulse numbers of the first electric motor M1, the second electric motor M2, and the third electric motor M3, are set as horizontal axes (x-axis), The axis representing the reference pulse number of the first electric motor M1, the second electric motor M2 and the third electric motor M3 is taken as the vertical axis (y axis), and the actual pulse number information of each of the electric motors M1 to M3 is converted into the conversion coefficients a1, a2 and a3 and the adjustment. It is a graph showing the conversion function at the time of converting into reference pulse number information after adjustment using coefficients α1, α2, and α3. As shown in this figure, when the actual pulse number of each of the motors M1 to M3 is x and the adjusted reference pulse number of each of the motors M1 to M3 is y, the conversion function of each of the motors M1 to M3 is “y = α1 · a1x ”,“ y = α2 · a2x ”, and“ y = α3 · a3x ”. The method for setting the adjustment coefficients α1, α2, and α3 will be described in detail later. In this embodiment, α1 = 1.05, α2 = 1.02, and α3 = 1. Since the conversion coefficients are a1 = 4, a2 = 2, and a3 = 1, the conversion function to the reference pulse number information after the adjustment is specifically, as shown by the solid line in FIG. “Y = 4.2x” for the electric motor M1, “y = 2.04x” for the second electric motor M2, and “y = x” for the third electric motor M3. For example, the slope is changed with respect to the conversion function (see FIG. 3) for converting to the reference pulse number information only by the conversion unit 4 indicated by a two-dot chain line in FIG. For example, when the actual pulse number of the first electric motor M1 at a certain time is “155” and the actual pulse number of the second electric motor M2 is “300”, the adjusted reference pulse number is “651” for the first electric motor M1, respectively. The second motor M2 is “612”, and the reference pulse number is “31” in the first motor M1 as compared to the reference pulse number after conversion by only the conversion unit 4 as shown in FIG. Then, the reference pulse number is converted to a value larger (advanced) by “12”. In this way, in the electric motor adjusted so that the adjusted reference pulse number is larger than the adjusted reference pulse number, the control unit 6 has a difference between the reference pulse number before and after the adjustment. Therefore, it is determined that the current state is advanced from that in the actual state. Therefore, the other electric motors are controlled to the lag side in accordance with the difference in the number of reference pulses before and after the adjustment. Therefore, the motors using the adjustment coefficients α1, α2, and α3 are adjusted so as to be controlled to the lag side as the adjustment coefficients α1, α2, and α3 are larger. Note that the adjustment coefficients α1, α2, and α3 may be values of 1 or less. In that case, the adjusted reference pulse number is adjusted to be smaller than the reference pulse number before adjustment, and the control unit 6 determines the difference between the reference pulse number before and after the adjustment. Therefore, each of the motors M1 to M3 is controlled forward with respect to the other motors according to the difference in the number of reference pulses before and after the adjustment. Will be. In this case, the smaller the values of the adjustment coefficients α1, α2, and α3 are adjusted such that the motors using the adjustment coefficients α1, α2, and α3 are controlled to the forward side.

  Next, a method for setting the values of the adjustment coefficients α1, α2, and α3 of the adjustment unit 7 will be described. The adjustment coefficients α1, α2, and α3 are, for each of the plurality of electric motors M1 to M3, one of the difference between the theoretical operation speed and the upper limit operation speed of each of the electric motors M1 to M3 and the height of the request for delaying the operation stop. It is preferable to set the value based on both.

  First, “the difference between the theoretical operating speed of each of the motors M1 to M3 and the upper operating speed” will be described. In the present embodiment, the speeds v1 to v3 of the electric motors M1 to M3 are controlled by PWM (Pulse Width Modulation) control, so that the speeds v1 to v3 of the electric motors M1 to M3 are increased or decreased. Control is performed by increasing or decreasing the duty ratio. In such control, an electric motor whose duty ratio during operation is close to 100% and the difference between the actual operation speed and the upper limit operation speed is small has no margin because it operates at a speed close to the upper limit of the operation speed. In many cases, the motor tends to lag behind other motors within the permissible range R, whereas a motor with a low duty ratio during operation and a large difference between the actual operation speed and the upper limit operation speed is Since it is operating at a speed with a margin with respect to the upper limit, the motor tends to advance with respect to another motor within the allowable range R. Here, if the actual operation speed at each time point is detected and the difference from the upper limit operation speed is calculated, the burden of calculation processing increases. Therefore, instead of the actual operation speed, each of the motors M1 to M3 is as designed. The theoretical operating speed, which is the speed when an ideal operation is performed, is used. Then, it is estimated that the motor having a larger difference between the theoretical operating speed and the upper limit operating speed of each of the motors M1 to M3 has a margin in speed and is stable on the advance side, and the adjustment coefficient of the motor is set to be different from that of the other motors. Set a large value for the adjustment factor. Thereby, it is possible to determine that the reference pulse number of the motor that tends to advance is more advanced than the actual in the control unit 6, and adjust the motor that tends to advance so that the speed is controlled to the delay side. be able to.

  Next, “the height of the request for delaying the operation stop” will be described. As described above, each of the electric motors M1 to M3 may cause the advance or delay of the reference pulse number within the allowable range R. However, with respect to the advance or delay that occurs within the allowable range R, each of the electric motors M1 to M3 It may be necessary to control the electric motor to stop in a predetermined order according to a request from the drive target side. That is, in the present embodiment, each of the electric motors M1 to M3 is responsible for the operations of the rotation direction A, the front / rear sliding direction B, and the inner / outer sliding direction C of the seat 1 of the welfare vehicle 2, respectively. Advance within the permissible range R due to restrictions on the trajectory E that can be moved without hitting, or because it is necessary to operate the person sitting in the seat 1 so as not to feel unnatural. Or it may be necessary to make the stop order of the respective motors caused by the delay a predetermined order. Therefore, the request for the stop order of each of the motors M1 to M3 is expressed as the height of the request for delaying the operation stop for each of the motors M1 to M3. The adjustment coefficient of the motor is set to a larger value than the adjustment coefficient of the other motors. As a result, it is possible to determine that the reference pulse number of the motor that is highly requested to delay the operation stop is advanced in the control unit 6 so that the speed of the motor is controlled to the delay side. Can be adjusted. In addition, the request | requirement with respect to the stop order of each electric motor M1-M3 is represented as the height of the request | requirement which accelerates | stimulates the operation stop about each electric motor M1-M3, and adjustment of the electric motor is so high that the request | requirement height which accelerates this operation stop is high It is also possible to set the coefficient to a value smaller than the adjustment coefficient of other electric motors.

  The values of the adjustment coefficients α1, α2, and α3 of the adjustment unit 7 are such that the difference in the advance or delay of the reference pulse number of each of the electric motors M1 to M3, the order of operation stop of each of the electric motors M1 to M3, and the like are appropriate. Further, it may be determined in advance based on experiments or simulations. At this time, the adjustment coefficients α1, α2, and α3 are obtained by multiplying the theoretical pulse numbers at the arbitrary times of the electric motors M1 to M3 by the conversion coefficients a1, a2, and a3 and the adjustment coefficients α1, α2, and α3, respectively. 6 is preferably set so as to be within a range of values that fall within the allowable range R in FIG. By setting in this way, there is an adjustment range sufficient for adjusting the advance or delay of the reference pulse number of each of the motors M1 to M3 within the allowable range R, and the actual reference pulse before adjustment by the adjustment unit 7 Since the difference in number is at most twice the allowable range R, it is possible to prevent the degree of advance or delay of the reference pulse number of each of the motors M1 to M3 from being excessively adjusted. Such adjustment coefficients α1, α2, and α3 are stored in the storage unit 5 and are read out during the adjustment process in the adjustment unit 7.

  And in the control part 6, based on the reference pulse number information after adjustment of each electric motor M1-M3, the reference pulse number after adjustment in the arbitrary time of all the electric motors M1-M3 is settled in the fixed tolerance R. Thus, the operation control of each of the electric motors M1 to M3 is performed. That is, the control unit 6 compares the adjusted reference pulse number information of each of the motors M1 to M3, reduces the speed of the motor in which the adjusted reference pulse number advances beyond a certain allowable range R, and adjusts Control is performed to increase the speed of the motor whose later reference pulse number is delayed beyond a certain allowable range R. Here, the allowable range R is a range in which the electric motors M1 to M3 do not cause hunting, and can be determined in advance based on experiments, simulations, or the like. The control algorithm, the allowable range R, and the like in the control unit 6 are stored in the storage unit 5.

  FIG. 4 is an explanatory diagram illustrating a method for controlling the operation of each of the motors M1 to M3 by the control unit 6 according to the present embodiment. As shown in this figure, in the present embodiment, the controller 6 first calculates an average value Ave of the current adjusted reference pulse numbers of the electric motors M1 to M3. For example, as illustrated in FIG. 5 described above, the current reference pulse numbers after adjustment of the electric motors M1 to M3 are “651” for the first electric motor M1, “612” for the second electric motor M2, and the third electric motor, respectively. When M3 is “580”, these average values Ave are “Ave = 614.333...”. Therefore, it is next determined whether or not the current adjusted reference pulse number of each of the motors M1 to M3 is within a certain allowable range R before and after the average value Ave. In the present embodiment, as an example, the allowable range R is set to a range of “35” before and after the average value Ave as the center. If there is a motor whose reference pulse number after adjustment exceeds a certain allowable range R centered on this average value Ave (advanced), the speed of the motor is decreased, and this average value Ave is When there is a motor whose reference pulse number after adjustment exceeds a certain allowable range R at the center and is delayed (small), control is performed to increase the speed of the motor. In the example of FIG. 4, the adjusted reference pulse numbers of the second electric motor M2 and the third electric motor M3 are within the allowable range R centering on the average value Ave, so that the speed v2 and the second electric motor M2 3. Control of the speed v3 of the electric motor M3 is not performed, and the speeds v2 and v3 are maintained as they are, but the reference pulse number after the adjustment of the first electric motor M1 is “650” and the tolerance is centered on the average value Ave. Since the vehicle travels beyond the range R, control for reducing the speed v1 of the first electric motor M1 is performed. At this time, the reference pulse number before the adjustment of the first electric motor M1 is “620”, and if the adjustment by the adjusting unit 7 is not performed, the speed v1 should be maintained as it is. Thus, it is understood that the control for reducing the speed v1 of the first electric motor M1 is performed, and thus the first electric motor M1 is adjusted to be controlled to the lag side.

  The increase or decrease of the speeds v1 to v3 of the electric motors M1 to M3 is controlled by increasing or decreasing the duty ratio as described above. As a method of increasing or decreasing the duty ratio, for example, it is possible to increase or decrease the duty ratio by several percent every short time of about several tens of ms. As a result, the speeds v1 to v3 of the electric motors M1 to M3 increase or decrease every time the average value Ave is calculated, and the reference pulse number of the electric motors M1 to M3 falls within the allowable range R centered on the average value Ave. Thus, the speed can be controlled so that the number of reference pulses after adjustment of all the motors M1 to M3 falls within the allowable range R centered on the average value Ave without changing the speed rapidly. it can. Further, for example, by increasing or decreasing the duty ratio by a magnitude proportional to the difference from the average value Ave of the adjusted reference pulse number of each of the motors M1 to M3, the increase or decrease of the speeds v1 to v3 can be controlled. It is also possible to do this. The initial duty ratio at the start of operation of each of the motors M1 to M3 is stored in the storage unit 5.

  In the above embodiment, the case where the first electric motor M1, the second electric motor M2, and the third electric motor M3 start and stop at the same time has been described. However, in an actual electric motor control device, there are a plurality of electric motors. In some cases, the start time and stop time of the operation are different, and some motors may start to operate with a delay, or may be controlled to stop the operation first. When such control is performed, the operation of the operating motor is stopped or the operation of the stopped motor is not started as one control area, and the operation is performed for a plurality of operating motors for each control area. Take control. By doing so, even if there are those in which the operation start timing and the operation stop timing are different among the plurality of electric motors, only the plurality of electric motors in operation are targeted, which is completely different from the above embodiment. Control can be performed by a control device having a similar configuration.

  The present invention is suitable for a control device for performing synchronous control of a plurality of electric motors having different characteristics and / or loads, such as when driving in a plurality of directions by electric motors corresponding to the respective directions. Can be used.

The schematic diagram which shows the aspect of the movement of the seat of the welfare vehicle which is an example of the application object of the control apparatus of the electric motor which concerns on this embodiment. Functional block diagram of the motor control device according to the present embodiment The graph showing the conversion function at the time of converting real pulse number information into reference | standard pulse number information in the conversion part of the control apparatus of the electric motor which concerns on this embodiment Explanatory drawing which shows the method of operation control of each electric motor by the control part of the control apparatus of the electric motor which concerns on this embodiment. The graph showing the conversion function at the time of converting the actual pulse number information of each electric motor of the control apparatus of the electric motor which concerns on this embodiment into the reference pulse number information after adjustment

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Detection part 4 Conversion part 6 Control part 7 Adjustment part R Permissible range M1 1st motor M2 2nd motor M3 3rd motor S1, S2, S3 Sensor I1, I2, I3 Accumulator a1, a2, a3 Conversion coefficient alpha1, alpha2 , Α3 adjustment factor

Claims (4)

A control device that performs synchronous control of a plurality of electric motors having different one or both of characteristics and loads,
A detection unit that detects the actual operation amount of each motor and outputs it as actual operation amount information;
By multiplying each theoretical operation amount at an arbitrary point in time of the plurality of electric motors, conversion coefficients that take values such that the multiplied results coincide with each other are respectively obtained for the actual operation amount information of each electric motor. A conversion unit that multiplies and converts the reference movement amount information, which is a unified scale, and outputs the information ,
Based on the reference operation amount information of each motor, a control unit that performs operation control of each motor so that a reference operation amount at an arbitrary time of the plurality of motors is within a certain allowable range;
An adjustment unit that multiplies each conversion coefficient by an adjustment coefficient that adjusts the degree of advance or delay of the reference operation amount of each motor within an allowable range in the control unit;
An electric motor control device.   The motor control device according to claim 1, wherein the conversion coefficient is a constant determined for each electric motor based on a ratio of theoretical operation amounts of the plurality of electric motors.   The adjustment coefficient is set for each of the plurality of motors based on one or both of a difference between a theoretical operation speed of the motor and an upper limit operation speed, and a height of a request for delaying or accelerating the operation stop. The motor control device according to claim 1 or 2.   The operation control is performed for a plurality of motors that are operating in each control region, with a period of time during which the operation of the motor that is operating is stopped or the operation of the stopped motor is not started as one control region. The motor control device according to claim 1.

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