Motor control device, oil pressure generating device, motor control method and storage medium

Abstract

The present invention provides a motor control device, an oil pressure generating device, a motor control method and a storage medium, which can suppress the rapid decrease in motor speed that may occur when the motor is transferred from a current control state to a speed control state. The motor control device of the present invention includes: a current control unit, which performs current control for rotating the motor from a stopped state; a speed calculation unit, which calculates the actual speed of the motor; an acquisition unit, which acquires the target speed of the motor; a speed control unit, which performs speed control of the motor so that the actual speed of the motor becomes the target speed; and a correction unit, which corrects the target speed based on the relationship between the actual speed and the target speed when migrating from the current control state to the speed control; the speed control unit performs speed control when the target speed is corrected so that the actual speed becomes the target speed corrected by the correction unit.

Description

Technical Field

[0001] The invention relates to a motor control device, an oil pressure generating device, a motor control method and a storage medium. Background Art

[0002] There is known a technique for preventing a shaft of an induction motor from actually rotating excessively exceeding a preset rotation speed (for example, refer to Patent Document 1).

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 8-251967 Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] When current control (for example, current control based on a maximum current value) is performed to rotate the motor from a stopped state, the motor speed may increase in different ways depending on the load of the motor at that time. In such a case, when the control state is uniformly immediately transferred from the current control state to the speed control for making the motor speed consistent with the target speed, the motor speed may decrease rapidly. In such a case, there is a concern that the desired rotation state of the motor cannot be achieved due to the load.

[0008] The present invention is made to solve the above-mentioned problem, and an object of the present invention is to suppress a sudden decrease in motor rotation speed that may occur when shifting from a current control state to a speed control state.

[0009] [Technical means to solve the problem]

[0010] In order to solve the above-mentioned problem, one aspect of the present invention provides a motor control device, comprising:

[0011] a current control unit that performs current control for rotating the motor from a stopped state;

[0012] A rotation speed calculation unit, which calculates the actual rotation speed of the motor;

[0013] an acquisition unit, which acquires a target value of the rotation speed of the motor, that is, a target rotation speed;

[0014] a speed control unit that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; and

[0015] a correction unit that corrects the target speed acquired by the acquisition unit based on a relationship between an actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state by the current control unit is transitioned to the speed control by the speed control unit;

[0016] The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

[0017] [Effects of the Invention]

[0018] According to the present invention, it is possible to suppress a sudden decrease in the motor rotation speed that may occur when shifting from a current control state to a speed control state. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a diagram schematically showing an embodiment of a hydraulic pressure generating device.

[0020] Figure 2 This is a functional block diagram schematically showing one embodiment of a motor control device.

[0021] Figure 3 This is a schematic block diagram for explaining current control implemented by a current control unit.

[0022] Figure 4 This is a schematic block diagram for explaining how a target value acquisition unit acquires a target rotation speed.

[0023] Figure 5 This is a schematic block diagram for explaining speed control implemented by a speed control unit.

[0024] Figure 6 This is a diagram showing an example of a process flow executed by the motor control device according to the present embodiment.

[0025] Figure 7 It is a diagram showing various waveforms of comparative examples.

[0026] Figure 8 1 and 2 are diagrams showing various waveforms of an operation example of the motor control device according to the present embodiment when the target rotation speed is lower than the actual rotation speed.

[0027] Fig. 9 1 and 2 are diagrams showing various waveforms of an operation example of the motor control device according to the present embodiment when the target rotation speed is higher than the actual rotation speed.

[0028] [Explanation of Symbols]

[0029] 1: Hydraulic pressure generating device

[0030] 2: Motor drive system

[0031] 3: Hydraulic pump

[0032] 10: Motor control device

[0033] 12: Motor

[0034] 12a: Output shaft

[0035] 13: Rotation sensor

[0036] 14: Current sensor

[0037] 31: Box

[0038] 32: Supply Road

[0039] 110: Motor drive unit

[0040] 112: Current control unit

[0041] 114: Speed ​​calculation unit

[0042] 116: Target value acquisition unit

[0043] 118: Speed ​​control unit

[0044] 120: Correction Department DETAILED DESCRIPTION

[0045] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0046] Figure 1 This is a diagram schematically showing an embodiment of the oil pressure generating device 1 .

[0047] The oil pressure generating device 1 is a device for generating oil pressure, and is suitable for being mounted on a vehicle. Figure 1 As shown, the oil pressure generating device 1 includes a motor drive system 2 and an oil pressure pump 3 .

[0048] The motor driving system 2 includes a motor control device 10 and a motor 12 .

[0049] The motor control device 10 controls the hydraulic pump 3 by controlling the motor 12. The motor control device 10 is a processing device including, for example, a microcomputer, etc. The hardware structure of the motor control device 10 is arbitrary and may be the same as an on-vehicle electronic control unit (ECU).

[0050] The output shaft 12a of the motor 12 functions as a drive shaft of the hydraulic pump 3. The motor 12 is a three-phase brushless motor, but the number of phases is not limited thereto, and the detailed structure is arbitrary. In addition, the motor 12 can be directly connected to the hydraulic pump 3, or it can be connected via other mechanisms (not shown).

[0051] The hydraulic pump 3 is an electric pump, and when driven, it sucks oil in a tank 31 and discharges the oil to a supply path 32 .

[0052] In this way, the oil pressure generating device 1 of the present embodiment drives the oil pressure pump 3 via the motor drive system 2, thereby generating oil pressure. In addition, the oil pressure generated by the oil pressure pump 3 (i.e., the oil ejected by the oil pressure pump 3) can be used to drive the actuator or cool the heat generating parts of various vehicle-mounted electronic equipment, lubricate the movable parts, etc.

[0053] Figure 2 FIG. 1 is a functional block diagram schematically showing an embodiment of the motor control device 10. Figure 2 In FIG. 1 , the host ECU 4 is shown together with the motor 12 , the rotation sensor 13 , and the current sensor 14 as related configurations.

[0054] The host ECU 4 is an example of a control device higher than the motor control device 10, and gives various instructions to the motor control device 10. The rotation sensor 13 supplies an electrical signal corresponding to the rotation speed of the motor 12 as sensor information to the motor control device 10. The current sensor 14 detects the phase current of each phase flowing through the motor 12.

[0055] like Figure 2 As shown, the motor control device 10 includes a motor driving unit 110 , a current control unit 112 , a rotation speed calculation unit 114 , a target value acquisition unit 116 (an example of an acquisition unit), a speed control unit 118 , and a correction unit 120 .

[0056] The motor drive unit 110 includes, for example, an integrated circuit (IC) or an inverter, and controls the inverter (not shown) based on the drive duty cycle indicated by the current control unit 112 or the speed control unit 118, and applies a drive current (for example, a three-phase drive current) corresponding to the drive duty cycle to the motor 12.

[0057] The current control unit 112 performs current control for rotating the motor 12 from a stopped state. That is, the current control unit 112 performs current control for starting the motor 12. The current control performed by the current control unit 112 can be, for example, Figure 3 The form shown is realized. Figure 3 1 is a schematic block diagram for explaining the current control implemented by the current control unit 112. Figure 3In the example shown, in the current control unit 112, based on the deviation between the command current supplied from the host ECU 4 and the phase current (detection value) from the current sensor 14, a current proportional integral (PI) control unit 1121 calculates a command voltage. Then, in the duty ratio calculation processing unit 1122, a driving duty ratio (in Figure 3 In other examples, the driving duty ratio may always be a fixed value of a maximum value (for example, 100%). In this case, the maximum driving current within a variable range is applied to the motor 12.

[0058] The rotation speed calculation unit 114 calculates the rotation speed (actual rotation speed) of the motor 12 based on the sensor information from the rotation sensor 13. In another example, the rotation speed calculation unit 114 may calculate (estimate) the actual rotation speed of the motor 12 based on a parameter such as a drive current.

[0059] The target value acquisition unit 116 acquires the target speed, which is the target value of the speed of the motor 12. The target value acquisition unit 116 acquires (calculates) the target speed based on the command speed (an example of the command value) from the upper ECU 4. For example, the target value acquisition unit 116 may directly use the command speed from the upper ECU 4 as the target speed. Alternatively, the acquisition of the target speed by the target value acquisition unit 116 may be performed, for example, Figure 4 The form shown is realized. Figure 4 2 is a schematic block diagram for explaining how the target speed is acquired by the target value acquisition unit 116. Figure 4 In the example shown, the target value acquisition unit 116 calculates the difference between the command speed from the host ECU 4 and the command speed after filtering, and multiplies the difference by the filter gain (see Figure 4 Then, by adding the difference obtained by multiplying the filter gain to the command speed after filtering, the command speed after filtering is obtained as the target speed. That is, by filtering the command speed, the command speed after filtering is obtained as the target speed.

[0060] In the present embodiment, as an example, the target value acquisition unit 116 acquires two target speeds. That is, the target value acquisition unit 116 acquires the command speed from the upper ECU 4 as the first target speed, and acquires the command speed after filtering as the second target speed. In the following, in addition to the case where the first target speed and the second target speed are specially distinguished, there is also a case where they are not distinguished and are referred to as "target speed".

[0061] The speed control unit 118 controls the speed of the motor 12 so that the actual speed of the motor 12 calculated by the speed calculation unit 114 becomes the target speed acquired by the target value acquisition unit 116. The speed control performed by the speed control unit 118 can be, for example, Figure 5 The form shown is realized. Figure 5 1 is a schematic block diagram for explaining the speed control implemented by the speed control unit 118. Figure 5 In the example shown, in the speed control unit 118, the command current is calculated by the speed PI control unit 1181 based on the deviation between the target speed acquired by the target value acquisition unit 116 and the actual speed calculated by the speed calculation unit 114. Then, the command voltage is calculated by the current PI control unit 1182 based on the deviation between the command current and the phase current (detection value) from the current sensor 14. Then, the duty ratio calculation process is performed based on the command voltage, thereby calculating the drive duty ratio supplied to the motor drive unit 110.

[0062] When the motor 12 is started, the speed control performed by the speed control unit 118 is performed immediately after the current control performed by the current control unit 112. In the present embodiment, the control state of the motor control device 10 selectively includes the speed control state caused by the speed control unit 118 and the current control state caused by the current control unit 112. When the motor 12 is started, the transition from the current control state to the speed control state is achieved when a prescribed transition condition is satisfied. The prescribed transition condition is, for example, satisfied when the actual rotation speed calculated by the rotation speed calculation unit 114 exceeds a threshold value. Alternatively, the prescribed transition condition may also be satisfied when the current control state caused by the current control unit 112 continues for more than a prescribed time. Alternatively, the prescribed transition condition may also be satisfied when the rotation amount of the motor 12 exceeds a threshold value (for example, 1 rotation).

[0063] In the present embodiment, as an example, after the transition from the current control state to the speed control state is completed, the speed control unit 118 performs speed control of the motor 12 based on the second target speed. Moreover, in the present embodiment, when the transition from the current control state to the speed control state is completed, the speed control unit 118 performs speed control of the motor 12 based on the corrected second target speed when the second target speed is corrected by the correction unit 120. That is, the speed control unit 118 performs speed control of the motor 12 so that the actual speed of the motor 12 calculated by the speed calculation unit 114 becomes the second target speed corrected by the correction unit 120. On the other hand, when the transition from the current control state to the speed control state is completed, the speed control unit 118 performs speed control of the motor 12 based on the first target speed when the second target speed is not corrected by the correction unit 120.

[0064] When the current control state caused by the current control unit 112 is transferred to the speed control performed by the speed control unit 118, the correction unit 120 corrects the second target speed obtained by the target value acquisition unit 116 based on the relationship between the actual speed of the motor 12 calculated by the speed calculation unit 114 and the target speed (in this embodiment, as an example, the first target speed) obtained by the target value acquisition unit 116. Hereinafter, the correction process for the second target speed performed by the correction unit 120 when the current control state caused by the current control unit 112 is transferred to the speed control performed by the speed control unit 118 is also simply referred to as "correction process". In addition, in another example, the command speed supplied by the upper ECU 4 may be equivalently corrected instead of correcting the second target speed obtained by the target value acquisition unit 116.

[0065] The correction processing performed by the correction unit 120 is preferably implemented as described below, for example. When the first target rotation speed acquired by the target value acquisition unit 116 is lower than the actual rotation speed of the motor 12 calculated by the rotation speed calculation unit 114, the correction unit 120 corrects the second target rotation speed acquired by the target value acquisition unit 116 in a direction close to the actual rotation speed. That is, the second target rotation speed is brought close to the actual rotation speed.

[0066] In the present embodiment, the correction process performed by the correction unit 120 is a process of correcting the second target rotation speed so as to be substantially the same as the actual rotation speed. The term “substantially the same” means that an error of about 10% of the actual rotation speed is allowed, for example.

[0067] Figure 6 FIG. 2 shows an example of a process flow executed by the motor control device 10 of the present embodiment. Figure 6 In FIG. 1 , the motor control device 10 has Status indicating three states. Status=0 indicates a current control state, Status=1 indicates a speed control state, and Status=2 indicates a transition state from a current control state by the current control unit 112 to a speed control state by the speed control unit 118 .

[0068] The motor control device 10 acquires various sensor information of this cycle (sensor information from the rotation sensor 13 or the current sensor 14 ), and acquires various commands from the host ECU 4 (step S600 ).

[0069] Next, the motor control device 10 calculates the actual rotation speed of the motor control device 10 based on the sensor information, and obtains the target rotation speed (the first target rotation speed and the second target rotation speed) (step S602). Then, the motor control device 10 determines whether the motor 12 is in a stopped state (step S604). Whether the motor 12 is in a stopped state can be determined, for example, by determining whether the actual rotation speed of the motor 12 calculated by the rotation speed calculation unit 114 is 0. When the motor 12 is in a stopped state ("YES" in step S604), the motor control device 10 sets Status = 0 (step S606). In addition, the initial value of Status can be 0.

[0070] The motor control device 10 determines whether the command current from the upper ECU 4 is greater than 0 (step S608). That is, it is determined whether a drive command for the motor 12 is generated from the upper ECU 4. When the command current is greater than 0 ("YES" in step S608), the current control is executed (started) (step S610). In addition, when the command current is 0 ("NO" in step S608), the processing of this cycle ends.

[0071] On the other hand, when the motor 12 is not in the stopped state ("NO" in step S604), the motor control device 10 determines whether Status = 0 (step S612). When Status = 0 ("YES" in step S612), it is determined that the predetermined transition condition is satisfied, and after setting Status = 2 (step S614), the process proceeds to step S618. In contrast, when Status = 0 ("NO" in step S612), the motor control device 10 determines whether Status = 2 (step S616). When Status = 2 ("YES" in step S616), the process proceeds to step S626 via step S624. When Status = 2 ("NO" in step S616), that is, when Status = 1, the process proceeds to step S626 to execute the speed control (step S626). In this case, speed control is performed based on the second target rotation speed acquired by the target value acquisition section 116 .

[0072] In step S618, the motor control device 10 determines whether the first target speed is less than the actual speed. In addition, at this time, the motor control device 10 may also determine whether the first target speed is less than the actual speed by a predetermined value or more. When the first target speed is less than the actual speed ("YES" in step S618), a correction process is performed to make the second target speed consistent with the actual speed (step S620). Then, the motor control device 10 performs the speed control based on the corrected second target speed (=actual speed) (step S622). On the other hand, when the first target speed is not less than the actual speed ("NO" in step S618), Status=1 is set (step S624), and the speed control is performed (step S626). In the case, the second target speed acquired by the target value acquisition unit 116 is not corrected by the correction unit 120, and in the case, the speed control is performed based on the first target speed acquired by the target value acquisition unit 116.

[0073] So, according to Figure 6 The processing shown in step S620 can prevent the rotation speed of the motor 12 from decreasing sharply when the current control state is transferred to the speed control state. Figure 6 The processing shown can be set to Status = 1 or 2 based on the relationship between various parameters that may dynamically change at a predetermined period (for example, the target speed acquired by the target value acquisition unit 116 or the actual speed calculated by the speed calculation unit 114). Thus, the correction unit 120 can implement the correction processing within an appropriate period.

[0074] Secondly, refer to Figures 7 to 9 , an operation example and effect of the motor control device 10 according to the present embodiment will be described by comparing with a comparative example.

[0075] Figure 7 is an explanatory diagram of control of a comparative example, Figure 8 and Fig. 9 It is an explanatory diagram of an operation example of this embodiment. Figure 8 Indicates the situation where correction processing is performed. Fig. 9 Indicates that the correction process has not been executed. Figures 7 to 9 The various waveforms are shown when the horizontal axis is time and the vertical axis is the rotation speed of the motor 12. Figure 7 In the description, the first target rotation speed and the second target rotation speed are assumed to be substantially the same value, and are not distinguished and are referred to as “target rotation speed”.

[0076] The comparative example is different from the present embodiment in that the correction processing of the present embodiment is not always performed. Figure 7As shown, at time t0, the motor 12 in a stopped state is started by current control. Even if the actual speed is significantly higher than the target speed at time t1, speed control can be performed based on the target speed without correcting the target speed. Figure 7 As shown in the figure, when speed control starts, the actual speed decreases sharply (refer to Figure 7 The change from time point t1 to time point t2 in the graph).

[0077] However, the motor 12 drives the hydraulic pump 3 as described above, so when the actual rotation speed of the motor 12 is relatively high, the oil pressure of the hydraulic pump 3 increases accordingly. When the actual rotation speed of the motor 12 decreases sharply under the condition of relatively high oil pressure, there is a concern that the motor 12 may not be able to achieve the desired rotation state due to the load caused by the relatively high oil pressure. As a result, although Figure 7 Although this did not occur, it is possible that the motor 12 stops.

[0078] In contrast, in this embodiment, when the motor 12 in a stopped state is started by current control at time t0, and the actual speed is significantly higher than the first target speed at time t1, as shown in FIG. Figure 8 As shown in FIG. 1 , the second target rotation speed is corrected to the actual rotation speed by the correction process. As a result, unlike the comparative example, the actual rotation speed is not rapidly reduced, and the problem generated in the comparative example can be solved.

[0079] In addition, in this embodiment, if Fig. 9 As shown, when the actual speed at time t1 when the current control is started is lower than the first target speed, the speed control is performed based on the first target speed acquired by the target value acquisition unit 116 without executing the correction process.

[0080] Thus, according to the present embodiment, when the current control state is transferred to the speed control state, the correction process is performed only when the first target speed obtained by the target value acquisition unit 116 is significantly lower than the actual speed. That is, the correction process is performed only when the speed of the motor 12 may decrease sharply. Thus, the problems that may occur when the correction process is always performed can be eliminated. For example, when the second target speed is corrected in a manner consistent with the relatively low actual speed, problems such as delay in the timing of realizing the command speed from the upper ECU 4 may occur, but according to the present embodiment, the above problems can be eliminated.

[0081] As mentioned above, the embodiment of the present invention has been described in detail with reference to the drawings, but the specific structure is not limited to the embodiment, and also includes designs and the like within the scope that does not depart from the gist of the present invention.

[0082] In addition, the following supplementary notes are disclosed with respect to the above-mentioned embodiments of the present invention.

[0083] [Note 1]

[0084] A motor control device 10, comprising:

[0085] The current control unit 112 performs current control for rotating the motor from a stopped state;

[0086] The speed calculation unit 114 calculates the actual speed of the motor;

[0087] an acquisition unit (target value acquisition unit 116), which acquires a target value of the rotation speed of the motor, that is, a target rotation speed;

[0088] a speed control unit 118 that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; and

[0089] a correction unit 120 that corrects the target speed acquired by the acquisition unit based on a relationship between the actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state caused by the current control unit is transferred to the speed control performed by the speed control unit;

[0090] The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

[0091] According to Supplementary Note 1, it is possible to provide a motor control device that includes a correction unit and can suppress a sudden decrease in the motor rotation speed that may occur when shifting from a current control state to a speed control state.

[0092] [Note 2]

[0093] A motor control device according to Note 1, wherein the correction unit corrects the target speed acquired by the acquisition unit in a direction approaching the actual speed of the motor calculated by the speed calculation unit when the target speed acquired by the acquisition unit is lower than the actual speed of the motor calculated by the speed calculation unit.

[0094] According to the configuration described in Supplementary Note 2, when shifting from the current control state to the speed control state, even if the target speed (target speed before correction) is lower than the actual speed of the motor, a sudden decrease in the speed of the motor can be suppressed by correcting the target speed.

[0095] [Note 3]

[0096] According to the motor control device described in Note 2, wherein the correction unit corrects the target speed acquired by the acquisition unit so as to make it substantially the same as the actual speed of the motor calculated by the speed calculation unit when the target speed acquired by the acquisition unit is less than the actual speed of the motor calculated by the speed calculation unit.

[0097] According to the configuration described in Supplementary Note 3, when the current control state is shifted to the speed control state, even if the target speed is lower than the actual speed of the motor, the target speed can be appropriately corrected, thereby preventing the speed of the motor from being rapidly reduced.

[0098] [Note 4]

[0099] The motor control device according to any one of Notes 1 to 3, wherein the correction unit does not correct the target speed acquired by the acquisition unit when the target speed acquired by the acquisition unit is greater than the actual speed of the motor calculated by the speed calculation unit.

[0100] According to the configuration described in Supplementary Note 4, when shifting from the current control state to the speed control state, correction can be appropriately performed so that the rotation speed of the motor does not decrease suddenly, and the shift can be achieved quickly without performing correction.

[0101] [Note 5]

[0102] The motor control device according to any one of Notes 1 to 4, wherein the target speed is a command value supplied by a higher-level control device and includes a first target speed and a second target speed as command values ​​of the speed of the motor,

[0103] The acquisition unit acquires the current value of the second target speed based on a difference between the current value of the first target speed and the previous value of the second target speed,

[0104] The speed control unit performs the speed control after the transition so that the actual rotation speed of the motor becomes the second target rotation speed acquired by the acquisition unit.

[0105] The correction unit corrects the second target speed based on the relationship between the actual speed of the motor calculated by the speed calculation unit and the first target speed acquired by the acquisition unit during the transition.

[0106] The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the second target speed corrected by the correction unit when the second target speed acquired by the acquisition unit is corrected by the correction unit during the transition.

[0107] During the transition, when the second target rotation speed acquired by the acquisition unit has not been corrected by the correction unit, the speed control unit performs the speed control so that the actual rotation speed of the motor becomes the first target rotation speed acquired by the acquisition unit.

[0108] According to the configuration described in Supplementary Note 5, by using the second target rotation speed obtained by filtering after the transition, even when the gain of the speed control is set high in order to improve the disturbance responsiveness, the possibility of overshoot can be suppressed.

[0109] [Note 6]

[0110] The motor control device according to any one of Supplementary Notes 1 to 5, wherein the current control performed by the current control unit includes applying a maximum current within a variable range to the motor.

[0111] According to the structure described in Supplementary Note 6, the increase in the rotation speed when the motor is started can be promoted (good startability).

[0112] [Note 7]

[0113] The motor control device according to any one of Notes 1 to 6, wherein the motor is for the hydraulic pump 3 .

[0114] According to the configuration described in Supplementary Note 7, when shifting from the current control state to the speed control state, even in the case of a hydraulic pump in which the load on the motor tends to become relatively large, the possibility of the motor being stopped due to the relatively large load can be reduced.

[0115] [Note 8]

[0116] A motor drive system 2, comprising:

[0117] Motor 12; and

[0118] A motor control device 10 for controlling the motor;

[0119] The motor control device comprises:

[0120] a current control unit 112 for performing current control for rotating the motor from a stopped state;

[0121] The speed calculation unit 114 calculates the actual speed of the motor;

[0122] an acquisition unit (target value acquisition unit 116), which acquires a target value of the rotation speed of the motor, that is, a target rotation speed;

[0123] a speed control unit 118 that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; and

[0124] a correction unit 120 that corrects the target speed acquired by the acquisition unit based on a relationship between the actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state caused by the current control unit is transferred to the speed control performed by the speed control unit;

[0125] The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

[0126] According to Supplementary Note 8, it is possible to provide a motor drive system that includes a correction unit and can suppress a sudden decrease in the motor rotation speed that may occur when shifting from a current control state to a speed control state.

[0127] [Note 9]

[0128] An oil pressure generating device 1, comprising:

[0129] Hydraulic pump 3;

[0130] A motor 12 drives the hydraulic pump; and

[0131] A motor control device 10 for controlling the motor;

[0132] The motor control device comprises:

[0133] a current control unit 112 for performing current control for rotating the motor from a stopped state;

[0134] The speed calculation unit 114 calculates the actual speed of the motor;

[0135] an acquisition unit (target value acquisition unit 116), which acquires a target value of the rotation speed of the motor, that is, a target rotation speed;

[0136] a speed control unit 118 that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; and

[0137] a correction unit 120 that corrects the target speed acquired by the acquisition unit based on a relationship between the actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state caused by the current control unit is transferred to the speed control performed by the speed control unit;

[0138] The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

[0139] According to Supplementary Note 9, it is possible to provide the oil pressure generating device which, by including the correction unit, can suppress a rapid decrease in the motor rotation speed that may occur when shifting from the current control state to the speed control state.

[0140] [Note 10]

[0141] A motor control method, comprising:

[0142] a current control step of performing current control for rotating the motor from a stopped state;

[0143] A speed calculation step, calculating the actual speed of the motor;

[0144] An acquisition step of acquiring a target value of the rotation speed of the motor, that is, a target rotation speed;

[0145] a speed control step of performing speed control on the motor so that the actual speed of the motor calculated by the speed calculation step becomes the target speed acquired by the acquisition step; and

[0146] a correction step of correcting the target speed acquired by the acquisition step based on a relationship between an actual speed of the motor calculated by the speed calculation step and the target speed acquired by the acquisition step when the current control state caused by the current control step is transferred to the speed control performed by the speed control step;

[0147] The speed control step performs the speed control so that the actual speed of the motor calculated by the speed calculation step becomes the target speed corrected by the correction step when the target speed acquired by the acquisition step is corrected by the correction step.

[0148] According to Supplementary Note 10, it is possible to provide a motor control method that includes the correction step and can suppress a sudden decrease in the motor rotation speed that may occur when shifting from a current control state to a speed control state.

[0149] [Note 11]

[0150] A storage medium storing a motor control program, wherein the motor control program causes a computer to execute:

[0151] A current control process for performing current control for rotating the motor from a stopped state;

[0152] A speed calculation process is used to calculate the actual speed of the motor;

[0153] Acquisition processing, acquiring a target value of the rotation speed of the motor, that is, a target rotation speed;

[0154] a speed control process for performing speed control on the motor so that the actual speed of the motor calculated by the speed calculation process becomes the target speed acquired by the acquisition process; and

[0155] a correction process for correcting the target speed acquired by the acquisition process based on a relationship between an actual speed of the motor calculated by the speed calculation process and the target speed acquired by the acquisition process when the current control state caused by the current control process is transferred to the speed control performed by the speed control process;

[0156] The speed control process performs the speed control so that the actual speed of the motor calculated by the speed calculation process becomes the target speed corrected by the correction process when the target speed acquired by the acquisition process is corrected by the correction process.

[0157] According to Supplementary Note 11, there can be provided a storage medium storing a motor control program, wherein the motor control program includes a correction step and can suppress a sudden decrease in the motor rotation speed that may occur when shifting from a current control state to a speed control state.

Claims

1. A motor control device, comprising: a current control unit that performs current control for rotating the motor from a stopped state; A rotation speed calculation unit, which calculates the actual rotation speed of the motor; an acquisition unit, which acquires a target value of the rotation speed of the motor, that is, a target rotation speed; a speed control unit that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; as well as a correction unit that corrects the target speed acquired by the acquisition unit based on a relationship between an actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state by the current control unit is transitioned to the speed control by the speed control unit; The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

2. The motor control device according to claim 1, wherein: The correction unit corrects the target speed acquired by the acquisition unit toward the actual speed of the motor calculated by the speed calculation unit when the target speed acquired by the acquisition unit is lower than the actual speed of the motor calculated by the speed calculation unit.

3. The motor control device according to claim 2, wherein: When the target rotation speed acquired by the acquisition unit is lower than the actual rotation speed of the motor calculated by the rotation speed calculation unit, the correction unit corrects the target rotation speed acquired by the acquisition unit so as to be substantially the same as the actual rotation speed of the motor calculated by the rotation speed calculation unit.

4. The motor control device according to any one of claims 1 to 3, wherein: The correction unit does not correct the target rotation speed acquired by the acquisition unit when the target rotation speed acquired by the acquisition unit is greater than the actual rotation speed of the motor calculated by the rotation speed calculation unit.

5. The motor control device according to any one of claims 1 to 3, wherein: The target rotation speed is a command value supplied from a higher-level control device and includes a first target rotation speed and a second target rotation speed which are command values ​​of the rotation speed of the motor. The acquisition unit acquires the current value of the second target speed based on a difference between the current value of the first target speed and the previous value of the second target speed, After the migration, the speed control unit performs the speed control so that the actual rotation speed of the motor becomes the second target rotation speed acquired by the acquisition unit. The correction unit corrects the second target speed based on the relationship between the actual speed of the motor calculated by the speed calculation unit and the first target speed acquired by the acquisition unit during the transition. The speed control unit, during the transition, performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the second target speed corrected by the correction unit when the second target speed acquired by the acquisition unit is corrected by the correction unit. During the transition, when the second target rotation speed acquired by the acquisition unit has not been corrected by the correction unit, the speed control unit performs the speed control so that the actual rotation speed of the motor becomes the first target rotation speed acquired by the acquisition unit.

6. The motor control device according to any one of claims 1 to 3, wherein: The current control performed by the current control unit includes applying a maximum current within a variable range to the motor.

7. The motor control device according to any one of claims 1 to 3, wherein: The motor is used for a hydraulic pump.

8. An oil pressure generating device, comprising: Hydraulic pump; A motor, driving the oil pressure pump; as well as a motor control device for controlling the motor; The motor control device comprises: a current control unit that performs current control for rotating the motor from a stopped state; A rotation speed calculation unit, which calculates the actual rotation speed of the motor; an acquisition unit, which acquires a target value of the rotation speed of the motor, that is, a target rotation speed; a speed control unit that performs speed control on the motor so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed acquired by the acquisition unit; and a correction unit that corrects the target speed acquired by the acquisition unit based on a relationship between an actual speed of the motor calculated by the speed calculation unit and the target speed acquired by the acquisition unit when the current control state by the current control unit is transitioned to the speed control by the speed control unit; The speed control unit performs the speed control so that the actual speed of the motor calculated by the speed calculation unit becomes the target speed corrected by the correction unit when the target speed acquired by the acquisition unit is corrected by the correction unit.

9. A motor control method, comprising: a current control step of performing current control for rotating the motor from a stopped state; A speed calculation step, calculating the actual speed of the motor; An acquisition step of acquiring a target value of the rotation speed of the motor, that is, a target rotation speed; a speed control step of performing speed control on the motor so that the actual speed of the motor calculated by the speed calculation step becomes the target speed acquired by the acquisition step; as well as a correction step of correcting the target speed acquired by the acquisition step based on a relationship between an actual speed of the motor calculated by the speed calculation step and the target speed acquired by the acquisition step when the current control state caused by the current control step is transferred to the speed control performed by the speed control step; The speed control step performs the speed control so that the actual speed of the motor calculated by the speed calculation step becomes the target speed corrected by the correction step when the target speed acquired by the acquisition step is corrected by the correction step.

10. A storage medium storing a motor control program, wherein the motor control program causes a computer to execute: A current control process for performing current control for rotating the motor from a stopped state; A speed calculation process is used to calculate the actual speed of the motor; Acquisition processing, acquiring a target value of the rotation speed of the motor, that is, a target rotation speed; a speed control process for performing speed control on the motor so that the actual speed of the motor calculated by the speed calculation process becomes the target speed acquired by the acquisition process; as well as a correction process for correcting the target speed acquired by the acquisition process based on a relationship between an actual speed of the motor calculated by the speed calculation process and the target speed acquired by the acquisition process when the current control state caused by the current control process is transferred to the speed control performed by the speed control process; The speed control process performs the speed control so that the actual speed of the motor calculated by the speed calculation process becomes the target speed corrected by the correction process when the target speed acquired by the acquisition process is corrected by the correction process.

Images