Motor driven oil pump and method of controlling motor driven oil pump

Abstract

To smoothly control the rotational speed of a motor.SOLUTION: A control device 18 receives a first command value from a host controller 30 in every first period. Upon receiving a current first command value, the control device 18 calculates a second command value on the basis of division of a difference value between the current first command value and the last first command value by a predetermined value. The predetermined value is a value that is determined in advance by dividing the first period by a second period shorter than the first period. The control device 18 executes motor control based on the second command value in every second period, which is shorter than the first period.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an electric oil pump and a method for controlling an electric oil pump. [Background technology]

[0002] For example, JP 2018-013209 A (Patent Document 1) discloses an electric oil pump device. This electric oil pump device supplies hydraulic pressure to hydraulically operated equipment such as an automatic transmission gear. The control device of the electric oil pump acquires a command value from a higher-level controller at regular intervals (hereinafter also referred to as a "communication cycle"). The command value is, for example, a rotation speed, torque, or current. Then, each time the electric oil pump acquires the command value, it executes feedback control based on the command value of the motor rotation speed. The electric oil pump controls the flow rate and pressure of the oil by executing this feedback control. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-013209 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above electric oil pump device, the control period of the feedback control of the control device depends on the above communication period. Therefore, even if the control period of the control device is shorter than the communication period, the control device executes feedback control in the communication period, which may cause a problem that the tracking of the motor control cannot be improved.

[0005] The present disclosure has been made to solve the above-mentioned problems, and has an object to improve the tracking performance of motor control. [Means for solving the problem]

[0006] The electric oil pump of the present disclosure includes a pump unit, a motor that drives the pump unit, and a control device that executes motor control, which is control of the motor. The control device receives a first command value from a higher-level controller every first period. Furthermore, when receiving the current first command value, the control device calculates a second command value based on a difference value between the current first command value and the previous first command value divided by a predetermined value. The predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period. Then, the control device executes motor control based on the second command value every second period.

[0007] The control method disclosed herein is a method for controlling an electric oil pump. The electric oil pump includes a pump unit and a motor that drives the pump unit. The control method includes receiving a first command value from a host controller for each first period. The control method also includes, when the first command value is currently received, calculating a second command value by dividing a difference value between the currently received first command value and a previously received first command value by a predetermined value. The predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period. The control method also includes executing motor control based on the second command value for each second period. Effect of the Invention

[0008] According to the present disclosure, it is possible to improve the tracking performance of motor control. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a configuration of an oil pump system according to an embodiment of the present invention; [Diagram 2] 2 is an example of a hardware configuration of a microcomputer. [Diagram 3] FIG. 2 is a diagram illustrating a configuration of a control device. [Figure 4] 13 is a flowchart showing a process flow of a generation unit. [Diagram 5] 11A and 11B are diagrams for explaining a command rotation speed etc. in a comparative example. [Figure 6] 4 is a diagram for explaining a command rotation speed etc. in the present embodiment. FIG. [Figure 7] 4 is a diagram for explaining a command rotation speed etc. in the present embodiment. FIG. [Figure 8] 1 is a schematic diagram of an electric oil pump according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, when numbers, amounts, etc. are mentioned, the scope of the present disclosure is not necessarily limited to the numbers, amounts, etc., unless otherwise specified. The same reference numbers are given to the same parts and corresponding parts, and duplicate descriptions may not be repeated. It is intended from the beginning that the configurations in the embodiments will be used in appropriate combination.

[0011] [Oil pump system] An oil pump system 5 according to the present embodiment is mounted on, for example, a vehicle. The oil pump system 5 supplies hydraulic pressure to hydraulically actuated equipment such as an automatic transmission gear. FIG. 1 is a block diagram showing a configuration of the oil pump system 5 according to the present embodiment. The oil pump system 5 includes a host controller 30 and an electric oil pump 10 capable of communicating with the host controller 30. In this embodiment, the electric oil pump 10 used in an automatic transmission of a vehicle is described. Specifically, the oil pump system 5 supplies hydraulic pressure to hydraulically actuated equipment such as an automatic transmission (AT) gear. In this embodiment, CAN (Controller Area Network) communication is adopted as a communication protocol between the host controller 30 and the host controller 30.

[0012] The electric oil pump 10 includes an input interface (I / F: Interface) 11, an output interface 17, a pump unit 15, a motor 14 that drives the pump unit 15, a control device 18 that drives the motor 14, and a rotation speed sensor 16. The control device 18 includes a microcomputer 12 and an inverter 13 that drives the motor 14. In this manner, the control device 18 executes motor control, which is control of the motor 14. In this embodiment, the motor control includes feedback control, which will be described later. The microcomputer 12 includes a processing unit 52, a feedback control unit 54, and a duty unit 56.

[0013] The upper controller 30 transmits a first command value to the electric oil pump 10 every first period. The microcomputer 12 of the control device 18 executes motor control every second period. In this embodiment, the first period is a communication period between the upper controller 30 and the electric oil pump 10, and is set to 10 ms in this embodiment. The first command value is a target value for driving the motor 14. In this embodiment, the first command value is a command rotation speed of the motor 14. As a modified example, the first command value may be a torque value of the motor 14 or a current value to the motor 14. The second period is a period shorter than the first period, and in this embodiment, the second period is 1 ms. This second period is a control period of the microcomputer 12 (a period defined by the clock frequency of the microcomputer 12).

[0014] The input interface 11 receives a command rotation speed from the upper controller 30 for each first period. The input interface 11 outputs the received command rotation speed to the microcomputer 12. The processing unit 52 of the microcomputer 12 calculates a pseudo rotation speed by executing a calculation described below, and outputs the pseudo rotation speed to the feedback control unit 54. The pseudo rotation speed is a command rotation speed for smoothly controlling the rotation speed of the motor, and is a pseudo value different from the command rotation speed from the upper controller 30. Moreover, the pseudo rotation speed is a value smaller than the command rotation speed. The pseudo rotation speed corresponds to the "second command value" in the present disclosure.

[0015] The feedback control unit 54 calculates a command voltage based on the pseudo rotation speed for each second period (1 ms) and outputs the calculated command voltage to the duty unit 56.

[0016] The duty unit 56 outputs a control signal (duty) corresponding to the command voltage to the inverter 13. The inverter 13 drives the motor 14 to rotate based on the control signal. The motor 14 is driven to rotate, whereby the pump unit 15 operates.

[0017] The rotation speed sensor 16 detects the rotation speed of the motor 14. The rotation speed is input to a processing unit 52 and a feedback control unit 54 of the control device 18. The processing unit 52 transmits the rotation speed to the upper controller 30 via the output interface 17.

[0018] [Microcontroller hardware configuration] 2 is a diagram showing an example of a hardware configuration of the microcomputer 12. The microcomputer 12 includes a CPU (Central Processing Unit) 122, a memory 124, and the like. The memory 124 includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and the like. The ROM is a non-rewritable non-volatile memory, and the RAM is a volatile memory.

[0019] The ROM stores a program describing the processing procedures of the microcomputer 12. The CPU 122 loads the program stored in the ROM into a RAM or the like and executes it. The microcomputer 12 controls each part of the electric oil pump 10 in accordance with these programs. This control is not limited to processing by software, and can also be processed by dedicated hardware (electronic circuitry).

[0020] [Control device details] Fig. 3 is a diagram showing details of the control device 18. In Fig. 3, the duty unit 56 and the inverter 13 are not shown. The processing unit 52 has a receiving unit 62, a generating unit 63, and a storage unit 64. As the storage unit 64, a part of the memory 124 (see Fig. 2) is used. The feedback control unit 54 has a difference unit 55, a PID unit 53, and an adding unit 57.

[0021] The receiving unit 62 receives a command rotation speed every 10 ms (first period). The received command rotation speed is output to the generating unit 63. The generating unit 63 calculates a pseudo rotation speed by a process described later. The generating unit 63 outputs the pseudo rotation speed to the differencing unit 55. The differencing unit 55 outputs a difference value between the pseudo rotation speed from the generating unit 63 and the rotation speed based on the detection of the rotation speed sensor 16 to the PID unit 53 as a deviation. The PID unit 53 executes PID control based on this deviation.

[0022] The PID unit 53 has a Kp unit 562, a Kis unit 564, and a Kds unit 566. The Kp unit 562 executes P control to calculate a gain P. The Kis unit 564 executes I control to calculate a gain I. The Kds unit 566 executes D control to calculate a gain D. The gain P, the gain I, and the gain D are output to the addition unit 57.

[0023] The adder 57 calculates a command voltage, which is an operation amount, by adding the gain P, the gain I, and the gain D, and outputs the command voltage to the duty unit 56 (see FIG. 1). Then, the motor 14 is controlled by the duty unit 56 and the inverter 13.

[0024] [Generation process] 4 is a flowchart showing the flow of processing by the generating unit 63. The generating unit 63 executes the processing of this flowchart every second period (1 ms). First, in step S2, the generating unit 63 determines whether or not it has received a current value from the upper controller 30. Here, the "current value" is the first command value (command rotation speed) that the generating unit 63 has received currently from the upper controller 30. The current value corresponds to the "current first command value" of the present disclosure.

[0025] In step S2, when the generating unit 63 determines that the current value has been received (YES in step S2), in step S4, the previous value is read from the storage unit 64. The previous value is a value stored in step S12 described later. The previous value is the first command value that the generating unit 63 received (previously received) immediately before the current value A2.

[0026] Next, in step S6, the generation unit 63 calculates the increase value ΔA by the following formula (1). Increased value ΔA = (current value A2 - previous value A1) ÷ predetermined value N (1) The increase value ΔA corresponds to the "division value" in the present disclosure. Moreover, the processing in step S6 corresponds to the "division processing" in the present disclosure. Moreover, the current value A2 in equation (1) is the value received in step S2, and the previous value A1 in equation (1) is the value read in step S4. The previous value A1 corresponds to the "previous first command value" in the present disclosure.

[0027] Furthermore, the predetermined value N in formula (1) is a predetermined value (fixed value). In this embodiment, the predetermined value N is a value obtained by dividing the first period T1 by the second period T2. In other words, it is expressed by the following formula (2). Predetermined value N = T1 ÷ T2 (2) Next, in step S8, the generation unit 63 updates the increase value ΔA stored in the storage unit 64. Specifically, the generation unit 63 erases the increase value ΔA calculated previously, and stores the increase value ΔA calculated in step S6 in the storage unit 64. The process of step S8 corresponds to the "storage process" of the present disclosure.

[0028] Next, in step S10, the generation unit 63 calculates a current pseudo value by adding the increase value ΔA to the previous value A1. That is, the current pseudo value is calculated by the following formula (3). Current pseudo value B2 = previous value A1 + increase ΔA (3) The current pseudo value B2 calculated by equation (3) corresponds to the pseudo rotation speed in FIG. 1. The process of step S10 corresponds to the "first calculation process" of the present disclosure. Next, in step S12, the generation unit 63 stores the current value A2 (the current value acquired in step S2) as the previous value A1. Due to this storage, in the next step S4, the current value A2 is read out as the previous value A1.

[0029] Next, in step S14, the generation unit 63 outputs the current pseudo value calculated in step S10 to the difference unit 55. Next, in step S16, the generation unit 63 stores the current pseudo value B2 as the previous pseudo value B1.

[0030] In addition, in step S2, if the current value A2 has not been received (NO in step S2), the process proceeds to step S18. In step S18, the generation unit 63 reads the increase value ΔA from the storage unit 64. The process of step S18 corresponds to the "read process" of the present disclosure. Here, the increase value ΔA is the increase value updated in step S8.

[0031] Next, in step S20, the generation unit 63 reads out the previous pseudo value B1. Here, the previous pseudo value B1 is the previous pseudo value stored in step S16. Next, in step S22, the generation unit 63 calculates the current pseudo value B2 by adding the increase value ΔA to the previous pseudo value B1. That is, the generation unit 63 calculates the current pseudo value B2 by the following formula (4). Current pseudo value B2 = Previous pseudo value B1 + Increase value ΔA (4) The current pseudo value B2 calculated by equation (4) corresponds to the pseudo rotation speed in FIG. 1. The process of step S22 corresponds to the "second calculation process" of the present disclosure. Then, the process proceeds to step S14. Moreover, steps S4 to S12 correspond to the "first process" of the present disclosure. Moreover, steps S18 to S22 correspond to the "second process" of the present disclosure.

[0032] Next, a specific example of the process in Fig. 4 will be described using specific numerical values. Here, the previous value A1 is 1400 rpm, and the current value A2 is 1500 rpm. As described above, the first period T1 is 10 ms, and the second period T2 is 1 ms.

[0033] In this specific example, when the generation unit 63 receives "1500 rpm" as the current value A2 in step S2, the generation unit 63 reads out "1400 rpm" as the previous value A1 in step S4. Then, the generation unit 63 calculates "10" as the increase value ΔA by the following formula (5) in step S6 (see also formula (1) above). Increase ΔA = (1500-1400)÷10 = 10 (5) In addition, in step S8, the generation unit 63 updates the previous increase value to "10", which is the current increase value ΔA. Next, in step S10, the generation unit 63 calculates "1410 rpm" as the current pseudo value B2 by the following formula (6) (see also the above formula (3)). This time, the pseudo value B2 = 1400 + 10 = 1410 (6) Next, in step S12, the generation unit 63 updates the previous value A1 in the storage unit 64, which is "1400 rpm," to the current value A2, which is "1500 rpm."

[0034] Next, in step S14, the generation unit 63 outputs "1410 rpm" as the current pseudo-value B2 to the difference unit 55. Next, in step S16, the previous pseudo-value B1 is updated to "1410 rpm" which is the current pseudo-value B2.

[0035] Furthermore, the generation unit 63 does not receive the current value A2 1 ms after the timing of receiving the current value A2 of "1500 rpm" (after the second period has elapsed). Therefore, at the timing after 1 ms has elapsed (after the second period has elapsed), NO is determined in step S2, and the process proceeds to step S18.

[0036] In step S18, the generation unit 63 reads out "10" as the increase value ΔA. This "10" is the value updated in step S8. Next, in step S20, the generation unit 63 reads out "1410" as the previous pseudo value ΔB1. This "1410" is the value updated in step S16. Next, in step S20, the generation unit 63 calculates "1420" as the current pseudo value ΔB2 by the following equation (7). This time, the pseudo value B2 = 1410 + 10 = 1420 (7) Furthermore, the processes of steps S18 to S22 are repeated until the next current value is received. That is, when the generation unit 63 receives "1500 rpm" as the current value, it calculates and outputs 1410 rpm as the current pseudo value in step S10. Thereafter, the generation unit 63 calculates and outputs 1420 rpm, 1430 rpm, . . . , 1500 rpm in step S22 for each second period (1 ms). That is, the control of the motor 14 includes control based on the second command value (1410 rpm) calculated in the process of step S14 (first calculation process) and control based on the second command value calculated in the process of step S22 (second calculation process).

[0037] [Effects of the electric oil pump of this embodiment] Next, the effects of the electric oil pump 10 of this embodiment will be described. First, the configuration of the electric oil pump of the comparative example will be briefly described. The electric oil pump of the comparative example receives a first command value from a higher-level controller every 10 ms. The microcomputer also executes feedback control every 10 ms (the microcomputer 12 of this embodiment executes feedback control every 1 ms).

[0038] FIG. 5 is a diagram for explaining the command rotation speed of the comparative example. FIG. 5(A) shows the time transition of the command rotation speed. FIG. 5(B) shows the time transition of the command voltage from the microcomputer. FIG. 5(C) shows the actual rotation speed of the motor. The horizontal axis of FIG. 5(A)-(C) and FIG. 6(A)-(C) described later shows time. The vertical axis of FIG. 5(A) and FIG. 6(A) shows the command rotation speed from the upper controller 30. The vertical axis of FIG. 5(B) and FIG. 6(B) shows the command voltage from the feedback control unit 54. The vertical axis of FIG. 5(C) and FIG. 6(C) shows the actual rotation speed of the motor 14. FIG. 5(A) and FIG. 6(A) also show 1400 rpm and 1500 rpm shown in the above-mentioned specific example.

[0039] In the example of FIG. 5(A), 1400 rpm is transmitted from the upper controller as the previous value, and 1500 rpm is transmitted from the upper controller as the current value. In the electric oil pump of the comparative example, a process is executed to increase the rotation speed of the motor by 100 rpm at a time. Therefore, as shown in FIG. 5(B), the change in the value of the command voltage when the current value is received is large, and the change gradually becomes smaller. For this reason, as shown in FIG. 5(C), unevenness occurs in the acceleration of the rotation speed, and a problem may occur in which the tracking ability of the motor rotation speed cannot be improved. Therefore, in the electric oil pump of the comparative example, a problem may occur in which the rotation speed of the motor cannot be smoothly controlled.

[0040] Also, in order to improve the tracking (response) of the motor rotation speed, it is possible to increase the PID gains P, I, and D of the feedback control. However, in such a configuration, a problem may occur in which the output from the feedback control unit oscillates.

[0041] In addition, in the invention according to the above-mentioned JP 2018-013209 A, in order to improve the responsiveness of the rotation speed of the motor, the oil temperature of the pump is estimated, and the feedback control gain is adjusted using not only the command value but also the oil temperature. However, in the invention according to this publication, the use of the oil temperature can cause a problem in that the calculation becomes complicated.

[0042] Fig. 6 is a diagram for explaining the command rotation speed of the electric oil pump 10 of this embodiment. In the example of Fig. 6(A), it is assumed that the electric oil pump 10 receives a command rotation speed of 1400 rpm as a previous value A1 from the upper controller 30 at timing t1. Timing t2 is a timing 10 ms after timing t1. It is assumed that the electric oil pump 10 receives a command rotation speed of 1500 rpm as a current value A2 from the upper controller 30 at timing t2.

[0043] When the electric oil pump 10 of this embodiment receives the current value A2 at timing t2, it increases the rotation speed of the motor 14 in multiple stages. In the example of Fig. 6, when 1500 rpm is received as the current value A2, the rotation speed is increased in multiple stages starting from 1400 rpm, as shown in part C. In this embodiment, the number of stages corresponds to the above-mentioned predetermined value N, and is "10".

[0044] Fig. 7 is an enlarged view of a portion C in Fig. 6. As shown in Fig. 7, the electric oil pump 10 calculates, for example, 10 rpm as the increased value ΔA (see the above formulas (1) and (4)). Then, as shown in formula (2), the current pseudo value B2 is increased stepwise from 1400 rpm to 1410 rpm, 1420 rpm, and so on.

[0045] In this way, the electric oil pump 10 of this embodiment can make the above-mentioned communication cycle (first cycle) virtually the same as the control cycle (second cycle) of the microcomputer 12 by executing the process of the above formula (1) and the like (the communication cycle and the control cycle can have the same resolution). Therefore, as shown in FIG. 6(B), the amount of fluctuation in the command voltage value can be reduced compared to the electric oil pump of the comparative example. As a result, as shown in FIG. 6(C), the unevenness in the acceleration of the rotation speed of the motor 14 can be suppressed. Therefore, the electric oil pump 10 of this embodiment can improve the responsiveness of the rotation speed and can improve the tracking of the control of the rotation speed of the motor 14. Furthermore, the electric oil pump 10 of this embodiment can also suppress the above problems.

[0046] Moreover, the second period T2 is the control period (1 ms) of the microcomputer 12 included in the control device 18. Therefore, the electric oil pump 10 can make the most of the performance of the microcomputer 12 to perform precise motor control.

[0047] As a modified example, the second period may be a second period T2' that is longer than the control period of the microcomputer 12. In such a configuration, the second period T2' may be a value that is an exact division of the first period T1. The predetermined value N is calculated in advance by dividing the first period T1 by the second period T2'. For example, even if the control period of the microcomputer 12 is 1 ms, the second period T2' may be 2 ms or 5 ms. If the second period T2' is 2 ms, the predetermined value N is "5."

[0048] In the above embodiment, the storage unit 64 is built into the electric oil pump 10. However, the storage unit 64 may be detachably attached to the electric oil pump 10.

[0049] 1, CAN communication is adopted as a communication protocol between the upper controller 30 and the upper controller 30. However, as shown in parentheses in FIG. 1, LIN (Local Interconnect Network) communication or PWM (Pulse Width Modulation) communication may be adopted as the protocol.

[0050] <Electric oil pump device> The structure of the electric oil pump 10 described above will be described in a simplified manner. FIG. 8 is a simplified diagram of the structure of the electric oil pump 10 according to the present disclosure. In the electric oil pump 10 according to the present disclosure, a pump section 15, a motor 14, a control device 18, and a rotation speed sensor 16 are arranged as shown in FIG. 8. The pump section 15 is a rotary pump that pumps oil. The motor 14 drives the pump section 15. The control device 18 includes a control circuit mounted on a board, and controls the driving of the motor 14. The rotation speed sensor 16 detects the rotation speed of the rotor in the motor 14. The detection value of the rotation speed sensor 16 is input to the control circuit of the control device 18.

[0051] [Note] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0052] (Item 1) The electric oil pump of the present disclosure includes a pump unit, a motor that drives the pump unit, and a control device that executes motor control, which is control of the motor. The control device receives a first command value from a higher-level controller for each first period. Furthermore, when receiving the current first command value, the control device calculates a second command value based on a difference value between the current first command value and the previous first command value divided by a predetermined value. The predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period. Then, the control device executes motor control based on the second command value for each second period.

[0053] (2) In the electric oil pump described in the 1st paragraph, the second period is a control period of a microcomputer included in the control device.

[0054] (3) In the electric oil pump described in 1 or 2, the electric oil pump has a memory. The control device judges whether or not a current first command value has been received from the higher-level controller for each second period. When the control device judges that a current first command value has been received, the control device executes a first process. When the control device judges that a current first command value has not been received, the control device executes a second process. The first process includes a division process, a storage process, and a first calculation process. The division process is a process of calculating a division value obtained by dividing a difference value by a predetermined value. The storage process is a process of storing the division value in the memory. The first calculation process is a process of calculating a second command value by adding the division value to a previous first command value. The second process includes a read process and a second calculation process. The read process is a process of reading out the division value stored in the memory. The second calculation process is a process of calculating a second command value by adding the division value to the second command value calculated in the first calculation process. The motor control includes control based on the second command value calculated by the first calculation process, and control based on the second command value calculated by the second calculation process.

[0055] (4) In the electric oil pump described in any one of paragraphs 1 to 3, the electric oil pump has a memory. Every time the control device receives a current first command value from the upper controller, the control device stores the first command value in the memory. The control device also obtains the stored current first command value from the memory as a previous first command value.

[0056] (Item 5) In the electric oil pump described in any one of Items 1 to 4, the host controller transmits the first command value to the control device by CAN communication.

[0057] (Item 6) In the electric oil pump described in any one of Items 1 to 4, the host controller transmits the first command value to the control device by LIN communication.

[0058] (Item 7) In the electric oil pump described in any one of Items 1 to 4, the host controller transmits the first command value to the control device by PWM communication.

[0059] (Item 8) A control method of the present disclosure is a control method for an electric oil pump. The electric oil pump includes a pump unit and a motor that drives the pump unit. The control method includes receiving a first command value from a host controller for each first period. The control method includes, when the first command value is currently received, calculating a second command value by dividing a difference value between the currently received first command value and a previously received first command value by a predetermined value. The predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period. The control method includes executing motor control based on the second command value for each second period.

[0060] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the embodiments described above, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0061] 5 Oil pump system, 10 Electric oil pump, 11 Input interface, 12 Microcomputer, 13 Inverter, 14 Motor, 15 Pump section, 16 Rotational speed sensor, 17 Output interface, 18 Control device, 30 Upper controller, 52 Processing section, 54 Feedback control section, 55 Differential section, 57 Addition section, 62 Receiving section, 63 Generation section, 64 Memory section.

Claims

1. A pump section; A motor that drives the pump unit; a control device that executes motor control, which is control of the motor; The control device includes: receiving a first command value from a host controller for each first period; when receiving a current first command value, a second command value is calculated by dividing a difference between the current first command value and a previous first command value by a predetermined value; the predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period, The control device further comprises: The electric oil pump executes motor control based on the second command value for each of the second cycles.

2. The electric oil pump according to claim 1 , wherein the second period is a control period of a microcomputer included in the control device.

3. The electric oil pump has a memory, The control device includes: determining whether or not the current first command value has been received from the upper controller for each second period; When it is determined that the current first command value has been received, a first process is executed; When it is determined that the current first command value has not been received, a second process is executed; The first process includes: a division process for calculating a division value by dividing the difference value by the predetermined value; a storage process for storing the divided value in the memory; a first calculation process of calculating a second command value by adding the divided value to the previous first command value, The second process includes: a read process for reading the division value stored in the memory; a second calculation process for calculating a second command value by adding the divided value to the second command value calculated in the first calculation process, 3. The electric oil pump according to claim 2, wherein the motor control includes control based on the second command value calculated by the first calculation process, and control based on the second command value calculated by the second calculation process.

4. The electric oil pump has a memory, The control device includes: storing the first command value in the memory every time the first command value is received from the upper controller; 4. The electric oil pump according to claim 1, wherein the stored current first command value is obtained from the memory as the previous first command value.

5. The electric oil pump according to any one of claims 1 to 3, wherein the host controller transmits the first command value to the control device by CAN (Controller Area Network) communication.

6. The electric oil pump according to any one of claims 1 to 3, wherein the host controller transmits the first command value to the control device by LIN (Local Interconnect Network) communication.

7. The electric oil pump according to any one of claims 1 to 3, wherein the host controller transmits the first command value to the control device by PWM (Pulse Width Modulation) communication.

8. A method for controlling an electric oil pump, comprising: The electric oil pump is A pump section; a motor that drives the pump unit, The control method includes: receiving a first command value from a higher-level controller for each first period; when a first command value is currently received, a difference value between the currently received first command value and a previously received first command value is divided by a predetermined value to calculate a second command value; the predetermined value is a value that is determined in advance by dividing the first period by a second period that is shorter than the first period, The control method further comprises: performing motor control based on the second command value for each second period.

Images