Drive control device

Abstract

To solve a problem in which a ripple current may occur when driving and controlling multiple loads by applying a drive voltage to them..SOLUTION: A drive control device disclosed herein includes a drive unit that generates pulse-width modulated drive voltages on the basis of a carrier signal that is a triangular wave or a sawtooth wave in accordance with operation amounts set for at least three loads, and applies the generated drive voltages to the respective load, and a carrier setting unit that sets a carrier signal set for a first load identified based on a comparison of the operation amounts set for the respective load as a reference carrier signal, sets a second carrier signal obtained by inverting the reference carrier signal for a second load different from the first load, and sets a third carrier signal obtained by shifting the phase of the reference carrier signal for a third load different from the first load and the second load.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a drive control device. [Background technology]

[0002] Patent Document 1 describes the drive control of a rotary solenoid as a plurality of loads. Specifically, in Patent Document 1, each load is driven and controlled by a drive voltage having a pulse-width modulated duty ratio required for each load. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-331696 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned Patent Document 1, there may be cases where the timing of applying the drive voltage to each load overlaps, which may cause a ripple current.

[0005] An object of the present disclosure is to solve the above-mentioned problem that ripple current may occur when a drive voltage is applied to a plurality of loads to control drive. [Means for solving the problem]

[0006] A drive control device according to one embodiment of the present disclosure includes: A drive unit that generates pulse-width modulated drive voltages in accordance with operation amounts set for at least three loads, based on a carrier signal that is a triangular wave or a sawtooth wave, and applies the generated drive voltages to the loads; a carrier setting unit that sets the carrier signal set for a first load identified based on a comparison of the manipulated variables set for each load as a reference carrier signal, sets a second carrier signal obtained by inverting the reference carrier signal for a second load different from the first load, and sets a third carrier signal obtained by shifting the phase of the reference carrier signal for a third load different from the first load and the second load; Equipped with The structure is as follows. Further, a control device according to an embodiment of the present disclosure includes: A driving unit is connected to the at least three loads, and generates a pulse-width modulated driving voltage based on a carrier signal having a triangular wave or a sawtooth wave in accordance with the operation amount set for each of the loads, and applies the generated driving voltage to each of the loads; the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. The structure is as follows. In addition, a control method according to an embodiment of the present disclosure includes: A drive voltage pulse-width modulated in accordance with a set operation amount for each of at least three loads is generated based on a carrier signal that is a triangular wave or a sawtooth wave, and is applied to each load. the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. The structure is as follows. Effect of the Invention

[0007] With the above-described configuration, the present disclosure can suppress the occurrence of ripple current when a drive voltage is applied to a plurality of loads for drive control. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a horizontal maintenance mechanism which is an example of a control target by a drive control device according to the present disclosure; [Diagram 2] 1 is a block diagram showing a configuration of a drive control device according to the present disclosure; [Diagram 3] FIG. 4 is a diagram showing a process performed by a drive control device according to the present disclosure. [Figure 4] FIG. 4 is a diagram showing a process performed by a drive control device according to the present disclosure. [Diagram 5] FIG. 4 is a diagram showing a process performed by a drive control device according to the present disclosure. [Figure 6] 5 is a flowchart showing a processing operation performed by a drive control device according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <Embodiment 1> The present disclosure will be described with reference to the drawings.

[0010] The drive control device in this embodiment is a device that drives and controls a plurality of loads in parallel, for example, a device that drives and controls a mechanism equipped with three DC motors in parallel. Here, an example of a mechanism equipped with three DC motors that is driven and controlled by the drive control device is a horizontal maintenance mechanism having a function of keeping a table T horizontal with respect to the ground surface G, as shown in FIG. 1. The horizontal maintenance mechanism supports the table T on the ground surface G with three legs, and the three legs are equipped with DC motors M1, M2, and M3, respectively, and is controlled to keep the table T horizontal by varying the length of each leg by driving the DC motors M1, M2, and M3. At this time, the variable amount of the length of each leg corresponds to the operation amount for driving and controlling each DC motor, and the DC motor is driven and controlled by applying a drive voltage to each DC motor for a time corresponding to the operation amount. The energization time of the drive voltage corresponding to the operation amount is controlled by a pulse-width modulated duty ratio. In this embodiment, the timing of supplying the drive voltage to each DC motor is controlled, thereby preventing the supply of drive voltage to each DC motor from overlapping, thereby suppressing the generation of ripple current.

[0011] Here, an example of the control of the horizontal maintenance mechanism will be described. For example, when the ground surface G is tilted from the state shown in FIG. 1(1-1) to the lower right with respect to the axis as shown in FIG. 1(1-2), the operation amount is controlled to be small in the direction of extending the leg length of the DC motor M1, and the operation amount is controlled to be large in the direction of shortening the leg length of the DC motor M2, as shown by the black arrow. Also, when the ground surface G is tilted from the state shown in FIG. 1(1-1) to the lower left with respect to the axis as shown in FIG. 1(1-3), the operation amount is controlled to be large in the direction of shortening the leg length of the DC motor M1, and the operation amount is controlled to be small in the direction of extending the leg length of the DC motor M2, as shown by the black arrow. Also, for example, when the ground surface G is tilted from the state shown in Fig. 1(1-1) toward the front with respect to the axis as shown in Fig. 1(1-4), the amount of operation is increased in the direction of shortening the length of the legs of DC motor M1, and the amount of operation is decreased in the direction of extending the lengths of the legs of DC motors M2 and M3, as shown by the black arrows. Note that in the case of such a horizontal maintenance mechanism, the relationship of table T to ground surface G is not always constant, and if the timing of energizing drive voltages to each DC motor is preset as described in the above-mentioned prior art document, ripple current may occur.

[0012] In this embodiment, a case where three DC motors are driven and controlled will be described, but the number of DC motors is not necessarily limited to three, and the present invention is also applicable to a case where a greater number of DC motors are driven and controlled. Furthermore, the object to be driven and controlled by applying a voltage is not limited to a DC motor, and may be any load that is driven and controlled according to the energization time of the applied drive voltage.

[0013] 2 is a block diagram showing the configuration of the drive control device in this embodiment. The drive control device is a device that drives and controls three DC motors M1, M2, M3 in parallel, and is composed of an information processing device equipped with a calculation device and a storage device. The drive control device is equipped with control setting units 11, 21, 31, drive units 12, 22, 32, and feedback units 13, 23, 33 corresponding to each of the DC motors M1, M2, M3, respectively, and further equipped with a carrier setting unit 40. Each unit equipped in the drive control device is realized by the calculation device executing a program.

[0014] Here, since the configurations provided corresponding to the DC motors M1, M2, M3 are the same, the following will describe in detail the configuration corresponding to one DC motor, the first DC motor M1.

[0015] 2, the drive control device includes a first control setting unit 11, a first driving unit 12, and a first feedback unit 13 corresponding to the first DC motor M1. First, the first feedback unit 13 detects the state of the first DC motor M1 with a rotation detection sensor, detects the rotation direction, and detects the number of rotations with a counter. Then, the first feedback unit 13 outputs the state of the first DC motor M1 based on the detected rotation direction, number of rotations, etc. to the first control setting unit 11, and constantly feeds back such state.

[0016] The first control setting unit 11 calculates and outputs an operation amount of the first DC motor M1 corresponding to the current state of the first DC motor M1. For example, the first control setting unit 11 has a reference value and a target value of the first DC motor M1, and in the above-mentioned example of the horizontal maintenance mechanism, the target value is calculated by a calculation device or the like from a difference in the corresponding inclination between the ground surface G and the table T. Then, the first control setting unit 11 obtains a current value from a difference between the current state of the first DC motor M1 outputted from the above-mentioned first feedback unit 13 and the reference value, and calculates an operation amount by controlling and adjusting the difference between the target value and the current value by a method such as PID control. Then, the first control setting unit 11 outputs the calculated first operation amount, which is the operation amount of the first DC motor M1, to the first drive unit 12.

[0017] The first drive unit 12 generates a drive voltage pulse-width modulated in response to the first operation amount output from the first control setting unit 11 in a PWM signal generating unit. At this time, the first control setting unit 11 generates a drive voltage with a duty ratio that results in a longer current application time as the first operation amount increases. Specifically, the first control setting unit 11 generates a first carrier signal set for the first DC motor M1 in a carrier setting unit 40 described later in a carrier signal generating unit, and generates a drive voltage in response to the first operation amount in a PWM signal generating unit based on the first carrier signal. Then, the first control setting unit 11 applies the generated drive voltage to the first DC motor M1 in a drive circuit unit to drive and control the first DC motor M1.

[0018] The above-mentioned configuration is also provided for the second DC motor M2 and the third DC motor M3. For this reason, for the second DC motor M2, the second control setting unit 21 calculates a second operation amount, which is an operation amount of the second DC motor M2, and the second driving unit 22 generates a drive voltage with a duty ratio corresponding to the second operation amount. At this time, the second driving unit 22 generates a drive voltage corresponding to the second operation amount based on a second carrier signal set for the second DC motor M2 by the carrier setting unit 40 described later. For the third DC motor M3, the third control setting unit 31 calculates a third operation amount, which is an operation amount of the third DC motor M3, and the third driving unit 32 generates a drive voltage with a duty ratio corresponding to the third operation amount. At this time, the third driving unit 32 generates a drive voltage corresponding to the third operation amount based on the second carrier signal set for the third DC motor M3 by the carrier setting unit 40 described later.

[0019] Next, the carrier setting unit 40 that sets each carrier signal used when generating the drive voltages of the DC motors M1, M2, and M3 in the above-mentioned drive units 12, 22, and 32 will be described. The carrier setting unit 40 first acquires each operation amount of the DC motors M1, M2, and M3 and compares the amounts. Then, the carrier setting unit 40 determines the maximum operation amount, the minimum operation amount, and other intermediate operation amounts. Here, FIG. 3 (3-1) shows an example of the energization time of the drive voltage generated according to each operation amount as described later. In this figure, the pulse width corresponding to the energization time of the drive voltage corresponds to the operation amount, so that the longer the pulse width, the larger the operation amount. In this example, it is determined that the second operation amount for the second DC motor M2 indicated by the symbol E2 is the maximum, the first operation amount for the first DC motor M1 indicated by the symbol E1 is the minimum, and the third operation amount for the third DC motor M3 indicated by the symbol E3 is the intermediate. Note that in FIG. 3, each drive voltage is shown in a time series, but the application timing is not determined at this point.

[0020] Then, the carrier setting unit 40 sets each carrier signal for each DC motor M1, M2, M3 based on the comparison result of the above-mentioned operation amount. First, the carrier setting unit 40 selects a carrier signal capable of generating a drive voltage for the second DC motor M2 having the maximum operation amount, as a reference carrier signal, as shown by reference symbol E2 in FIG. 3 (3-1). For example, the carrier setting unit 40 stores several reference carrier signals, and selects a reference carrier signal capable of generating a drive voltage for the second DC motor M2 having the maximum operation amount. That is, the carrier setting unit 40 sets the carrier signal set for the second DC motor M2 having the maximum operation amount as the reference carrier signal. At this time, a triangular wave or a sawtooth wave is used as the carrier signal, but in this embodiment, a sawtooth wave is used as the carrier signal. As a result, the carrier signal for the second DC motor M2 having the maximum operation amount is set as shown by reference symbol C2 in FIG. 3 (3-2).

[0021] The carrier setting unit 40 generates a carrier signal for generating a drive voltage for the first DC motor M1 with the smallest amount of operation, as shown by reference E1 in Fig. 4(4-1), based on the reference carrier signal C2 selected for the motor with the largest amount of operation. Specifically, the carrier setting unit 40 generates an inverted carrier signal by inverting the reference carrier signal C2, and sets it as the carrier signal for the first DC motor M1 with the smallest amount of operation. As a result, the carrier signal for the first DC motor M1 with the smallest amount of operation is set, as shown by reference C1 in Fig. 4(4-2).

[0022] The carrier setting unit 40 generates a carrier signal for generating a drive voltage for the third DC motor M3 having an intermediate operation amount, as shown by reference E3 in FIG. 5 (5-1), based on the reference carrier signal C2 selected for the motor having the maximum operation amount. Specifically, the carrier setting unit 40 generates a shift carrier signal by shifting the phase of the reference carrier signal C2, and sets it as the carrier signal for the third DC motor M3 having an intermediate operation amount. At this time, the carrier setting unit 40 sets a shift carrier signal by shifting the phase of the reference carrier signal C2 so that application of the drive voltage E3 to the third DC motor M3 having an intermediate operation amount starts at the timing when application of the drive voltage E2 to the second DC motor M2 having the maximum operation amount is turned off. As a result, the carrier signal for the third DC motor M3 having an intermediate operation amount is set, as shown by reference C3 in FIG. 5 (5-2). However, the carrier setting unit 40 is not limited to setting the shift carrier signal by shifting the reference carrier signal C2 as described above, and may set a shift carrier signal by shifting the phase of the reference carrier signal C2 so that the drive voltage E3 is applied to the third DC motor M3, whose operation amount is intermediate, during a period in which the drive voltage E2 is not applied to the second DC motor M2, whose operation amount is maximum. In other words, the shift carrier signal may be set by shifting the phase of the reference carrier signal C2 so that the rising edge of the shift carrier signal is positioned while the drive voltage E2 to the second DC motor M2, whose operation amount is maximum, is off.

[0023] [Operation] Next, the operation of the drive control device described above will be explained. The drive control device constantly feeds back the states of the three DC motors M1, M2, M3, and calculates each operation amount in each control setting unit 11, 21, 31. The drive control device then sets each carrier signal in the carrier setting unit 40 based on each operation amount, and generates drive voltages corresponding to each operation amount based on each carrier signal in each driving unit 12, 22, 32 to drive and control each DC motor M1, M2, M3 repeatedly. Below, the setting operation of the carrier signal by the carrier setting unit 40 will be mainly explained.

[0024] The carrier setting unit 40 inputs the operation amount of each of the DC motors M1, M2, and M3 (step S1 in FIG. 6) and compares the amounts. At this time, the carrier setting unit 40 determines, by comparing the operation amounts, whether the motor with the largest operation amount is the first DC motor, the second DC motor, or the third DC motor (steps S2 and S3 in FIG. 6). In addition, the carrier setting unit 40 also determines the motor with the smallest operation amount and the other motors with intermediate operation amounts.

[0025] Then, the carrier setting unit 40 sets each carrier signal for each of the DC motors M1, M2, M3 based on the comparison result of the operation amount. When the first operation amount for the first DC motor M1 is maximum (Yes in step S2 of FIG. 6), the carrier setting unit 40 selects a carrier signal capable of generating a drive voltage for the first DC motor M1 as a reference carrier signal. When the third operation amount for the third DC motor M3 is minimum, the carrier setting unit 40 generates and sets an inverted carrier signal obtained by inverting the reference carrier signal as a carrier signal for generating a drive voltage for the third DC motor M3. Furthermore, when the second operation amount for the second DC motor M2 is intermediate, the carrier setting unit 40 generates and sets a shifted carrier signal obtained by shifting the phase of the reference carrier signal as a carrier signal for generating a drive voltage for the second DC motor M2 (step S4 of FIG. 6).

[0026] Furthermore, when the second operation amount for the second DC motor M2 is maximum (No in step S2 and Yes in step S3 in FIG. 6), the carrier setting unit 40 selects a carrier signal capable of generating a drive voltage for the second DC motor M2 as a reference carrier signal. When the first operation amount for the first DC motor M1 is minimum, the carrier setting unit 40 generates and sets an inverted carrier signal obtained by inverting the reference carrier signal as a carrier signal for generating a drive voltage for the first DC motor M1. Furthermore, when the third operation amount for the third DC motor M3 is intermediate, the carrier setting unit 40 generates and sets a shifted carrier signal obtained by shifting the phase of the reference carrier signal as a carrier signal for generating a drive voltage for the third DC motor M3 (step S5 in FIG. 6). In this case, the carrier signals of the DC motors M1, M2, and M3 are set as shown in FIG. 3 to FIG. 5 described above.

[0027] Furthermore, when the third operation amount for the third DC motor M3 is maximum (No in step S2 and No in step S3 in FIG. 6), the carrier setting unit 40 selects a carrier signal capable of generating a drive voltage for the third DC motor M3 as a reference carrier signal. When the second operation amount for the second DC motor M2 is minimum, the carrier setting unit 40 generates and sets an inverted carrier signal obtained by inverting the reference carrier signal as a carrier signal for generating a drive voltage for the second DC motor M2. Furthermore, when the first operation amount for the first DC motor M1 is intermediate, the carrier setting unit 40 generates and sets a shifted carrier signal obtained by shifting the phase of the reference carrier signal as a carrier signal for generating a drive voltage for the first DC motor M1 (step S6 in FIG. 6).

[0028] As described above, after the reference carrier signal for the DC motor with the maximum operation amount is set by the carrier setting unit 40, the order of setting the carrier signal for the DC motor with the minimum operation amount and the carrier signal for the DC motor with the intermediate operation amount is not limited to the order described above, and either may be performed first, or may be performed in parallel.

[0029] Then, the carrier setting unit 40 outputs each of the set carrier signals to the carrier signal generating units of the driving units 12, 22, and 32 of the corresponding DC motors M1, M2, and M3 (step S7 in FIG. 6). As a result, the driving units 12, 22, and 32 generate driving voltages according to the respective operation amounts based on the respective carrier signals, and the driving of each of the DC motors M1, M2, and M3 is controlled.

[0030] As described above, in the drive control device of this embodiment, the carrier signal of one DC motor is set as a reference carrier signal according to the operation amount of the three DC motors M1, M2, and M3, and the carrier signals of the other two DC motors are set as an inverted carrier signal obtained by inverting the reference carrier signal and a shift carrier signal obtained by shifting the phase of the reference carrier signal. This makes it possible to effectively prevent the drive voltages generated based on each carrier signal from overlapping in time, and to suppress the generation of ripple current. Furthermore, in this embodiment, the carrier signal of the DC motor with the maximum operation amount is set as a reference carrier signal, the carrier signal of the DC motor with the minimum operation amount is set as an inverted carrier signal obtained by inverting the reference carrier signal, and the carrier signal of the DC motor with the intermediate operation amount is set as a shift carrier signal obtained by shifting the phase of the reference carrier signal. In addition, at this time, the shift carrier signal is set by shifting the phase of the reference carrier signal so that the application of the drive voltage to the DC motor with the maximum operation amount is started at the timing when the application of the drive voltage to the DC motor with the maximum operation amount is turned off. This makes it possible to more effectively prevent the drive voltages from overlapping in time, and to further suppress the generation of ripple current.

[0031] In the above, the carrier setting unit 40 sets an inverted carrier signal obtained by inverting the reference carrier signal as the carrier signal for the DC motor with the smallest manipulated variable, but an inverted carrier signal obtained by inverting the reference carrier signal may be set as the carrier signal for the DC motor with an intermediate manipulated variable. Accordingly, a shifted carrier signal obtained by shifting the phase of the reference carrier signal may be set as the carrier signal for the DC motor with the smallest manipulated variable. This also makes it possible to effectively prevent the drive voltages from overlapping in time, and to suppress the generation of ripple current.

[0032] Although the above-mentioned drive control device has been described as an example of driving and controlling three DC motors, it may be configured to drive and control four DC motors. In this case, the carrier setting unit 40 may set the carrier signals of the three DC motors in the same manner as described above, and set the carrier signal of the fourth DC motor by shifting the phase of the reference carrier signal so that application of the drive voltage starts at the timing when application of the drive voltage to the DC motor for which the above-mentioned shift carrier signal is set (for example, the third DC motor M3 in the example shown in FIG. 5 (5-2)) is turned off. Thereby, even if the number of DC motors to be driven and controlled is larger, it is possible to effectively suppress the drive voltages from overlapping in time as described above, and suppress the generation of ripple current.

[0033] The present disclosure is also applicable to the case of controlling the drive of even more DC motors (five or more DC motors). Furthermore, the present disclosure is not limited to the case of controlling the drive of a DC motor, but is also applicable to the case of controlling the drive of any load to which a drive voltage is applied.

[0034] <Additional Notes> A part or all of the above-described embodiments can be described as follows: Below, an outline of the configurations of the drive control device, the control device, and the control method according to the present disclosure will be described. However, the present disclosure is not limited to the following configurations. (Appendix 1) A drive unit that generates pulse-width modulated drive voltages in accordance with operation amounts set for at least three loads, based on a carrier signal that is a triangular wave or a sawtooth wave, and applies the generated drive voltages to the loads; a carrier setting unit that sets the carrier signal set for a first load identified based on a comparison of the manipulated variables set for each load as a reference carrier signal, sets a second carrier signal obtained by inverting the reference carrier signal for a second load different from the first load, and sets a third carrier signal obtained by shifting the phase of the reference carrier signal for a third load different from the first load and the second load; A drive control device comprising: (Appendix 2) The drive control device according to claim 1, The carrier setting unit identifies a load having a maximum operation amount as the first load. Drive control device. (Appendix 3) A drive control device according to claim 2, the carrier setting unit identifies a load having a minimum operation amount as the second load, and sets the second carrier signal for the second load. Drive control device. (Appendix 4) A drive control device according to claim 2, the carrier setting unit sets the third carrier signal obtained by shifting a phase of the reference carrier signal so that the drive voltage is applied to the third load during a period in which the drive voltage corresponding to the operation amount set for the first load is not applied to the first load. Drive control device. (Appendix 5) A drive control device according to claim 4, the carrier setting unit sets the third carrier signal obtained by shifting a phase of the reference carrier signal so as to start application of the drive voltage to the third load at a timing when application of the drive voltage to the first load is turned off. Drive control device. (Appendix 6) A drive control device according to claim 2, the carrier setting unit sets a carrier signal for starting application of the driving voltage to a fourth load different from the first load, the second load, and the third load at a timing when application of the driving voltage to the third load is turned off. Drive control device. (Appendix 7) A drive control device according to claim 2, the carrier setting unit identifies a load having a minimum operation amount as the third load, and sets the third carrier signal to the third load, and identifies a load having an operation amount between a maximum and a minimum as the second load, and sets the second carrier signal to the second load. Drive control device. (Appendix 8) The drive control device according to claim 1, the carrier signal is a sawtooth wave; Drive control device. (Appendix 9) The drive control device according to claim 1, The load is a DC motor. Drive control device. (Appendix 10) A driving unit is connected to the at least three loads, and generates a pulse-width modulated driving voltage based on a carrier signal having a triangular wave or a sawtooth wave in accordance with the operation amount set for each of the loads, and applies the generated driving voltage to each of the loads; the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. Control device. (Appendix 11) A drive voltage pulse-width modulated in accordance with a set operation amount for each of at least three loads is generated based on a carrier signal that is a triangular wave or a sawtooth wave, and is applied to each load. the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. Control methods. [Explanation of symbols]

[0035] 11 First control setting unit 12 First drive unit 13 First Feedback Section 21 Second control setting unit 22 Second drive unit 23 Second Feedback Section 31 Third control setting unit 32 Third Drive Unit 33 Third Feedback Section 40 Career setting section

Claims

1. A drive unit that generates pulse-width modulated drive voltages in accordance with operation amounts set for at least three loads, based on a carrier signal that is a triangular wave or a sawtooth wave, and applies the generated drive voltages to the loads; a carrier setting unit that sets the carrier signal set for a first load identified based on a comparison of the manipulated variables set for each load as a reference carrier signal, sets a second carrier signal obtained by inverting the reference carrier signal for a second load different from the first load, and sets a third carrier signal obtained by shifting the phase of the reference carrier signal for a third load different from the first load and the second load; A drive control device comprising:

2. The drive control device according to claim 1, The carrier setting unit identifies a load having a maximum operation amount as the first load. Drive control device.

3. The drive control device according to claim 2, the carrier setting unit identifies a load having a minimum operation amount as the second load, and sets the second carrier signal for the second load. Drive control device.

4. The drive control device according to claim 2, the carrier setting unit sets the third carrier signal obtained by shifting a phase of the reference carrier signal so that the drive voltage is applied to the third load during a period in which the drive voltage corresponding to the operation amount set for the first load is not applied to the first load. Drive control device.

5. The drive control device according to claim 4, the carrier setting unit sets the third carrier signal obtained by shifting a phase of the reference carrier signal so as to start application of the drive voltage to the third load at a timing when application of the drive voltage to the first load is turned off. Drive control device.

6. The drive control device according to claim 2, the carrier setting unit sets a carrier signal for starting application of the driving voltage to a fourth load different from the first load, the second load, and the third load at a timing when application of the driving voltage to the third load is turned off. Drive control device.

7. The drive control device according to claim 2, the carrier setting unit identifies a load having a minimum operation amount as the third load, and sets the third carrier signal to the third load; and identifies a load having an operation amount between a maximum and a minimum as the second load, and sets the second carrier signal to the second load. Drive control device.

8. The drive control device according to claim 1, the carrier signal is a sawtooth wave; Drive control device.

9. The drive control device according to claim 1, The load is a DC motor. Drive control device.

10. A driving unit is connected to the at least three loads, and generates a pulse-width modulated driving voltage based on a carrier signal having a triangular wave or a sawtooth wave in accordance with the operation amount set for each of the loads, and applies the generated driving voltage to each of the loads; the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. Control device.

11. A drive voltage pulse-width modulated in accordance with a set operation amount for each of at least three loads is generated based on a carrier signal having a triangular wave or a sawtooth wave, and the drive voltage is applied to each of the loads. the carrier signal set for a first load identified based on a comparison of the manipulated variables respectively set for each load is set as a reference carrier signal, a second carrier signal obtained by inverting the reference carrier signal is set for a second load different from the first load, and a third carrier signal obtained by shifting the phase of the reference carrier signal is set for a third load different from the first load and the second load. Control methods.

Images