JP6155958B2 - Control device for hydraulic power steering device - Google Patents

Description

  The present invention relates to a control device for a hydraulic power steering device.

  2. Description of the Related Art Conventionally, a hydraulic power steering device that applies an assist force to a steering system using a hydraulic actuator such as a hydraulic cylinder is widely known. For example, Patent Document 1 discloses a hydraulic power steering apparatus using two electric pumps that generate hydraulic pressure by driving two motors as a hydraulic source of a hydraulic actuator. In such a hydraulic power steering device, even when the steering operation is not performed, the electric pump is driven at a relatively low rotational speed (standby rotational speed), so that a quick assist force can be quickly applied. The improvement of the nature is aimed at.

JP 09-095251 A

  By the way, in such a hydraulic power steering apparatus using two electric pumps that generate hydraulic pressure by driving two motors, by operating the second electric pump after the first electric pump is operated, The steering feeling is improved. However, if the second electric pump is operated unconditionally after the first electric pump is operated, the operating state of the first electric pump is completely different from the operating state of the second electric pump. There was a problem that the ring felt uncomfortable.

  The present invention has been made to solve the above-described problems, and the object of the present invention is to enable the first electric pump to be operated even when the second electric pump is operated after the first electric pump is operated. It is an object of the present invention to provide a control device for a hydraulic power steering device that can improve the steering feeling by making the operating state and the operating state of the second electric pump the same.

  A control device for a hydraulic power steering apparatus that solves the above-described problems is provided with first and second hydraulic fluid supply units for supplying hydraulic oil to a hydraulic actuator that generates an assist force for assisting a steering operation in a steering system using a motor as a drive source. In the control apparatus of the hydraulic power steering apparatus including the electric pump, the control means for controlling the operation of the hydraulic actuator through the supply of the driving power to the motor, and the control means has a speed feedback having a proportional element and an integral element. A control unit, a current feedback control unit having a proportional element and an integral element, an integration state quantity storage means for storing the integration state quantity of the speed feedback control unit and the integration state quantity of the current feedback control unit. The control means is delayed from the operation of the first electric pump, and the second When operating the dynamic pump, the integral state quantity of the speed feedback control unit and the integral state quantity of the current feedback control unit of the first electric pump are read from the integral state quantity storage unit, and the second The second aspect is to start the operation of the second electric pump after tracing the integrated state quantity storage means of the speed feedback control unit and the current feedback control unit of the electric pump.

  According to the above configuration, the integral state quantity of the speed feedback control unit that drives the first electric pump and the integral state quantity of the current feedback control unit, which greatly affect the control performance of the electric pump, are continuously stored. When the second electric pump is operated later than the operation of the first electric pump, the integration state quantity of the speed feedback control unit of the first electric pump and the integration state quantity of the current feedback control unit are integrated. Reading from the state quantity storage means and tracing to the integrated state quantity storage means of the speed feedback control unit and current feedback control unit of the second electric pump. As a result, the integrated state quantity of the first electric pump and the integrated state quantity of the second electric pump, which have a great influence on the control performance of the electric pump, are the same, so that the steering feeling can be improved.

  According to the present invention, even when the second electric pump is operated behind the operation of the first electric pump, the operating state of the first electric pump and the operating state of the second electric pump are made the same. In addition, it is possible to provide a control device for a hydraulic power steering apparatus that can improve steering feeling.

The schematic block diagram of a hydraulic power steering device. 1 is a schematic control block diagram of a hydraulic power steering device. The detailed control block diagram of a 1st microcomputer. The detailed control block diagram of a 2nd microcomputer. The flowchart which shows the control procedure of the 1st and 2nd electric pump in the case of operating a 2nd electric pump after a 1st electric pump act | operates. The map figure in the target speed command value calculating part of a 1st and 2nd microcomputer.

Hereinafter, embodiments of a hydraulic power steering apparatus will be described with reference to the drawings.
A hydraulic power steering apparatus 1 shown in FIG. 1 is mounted on a vehicle having an idle stop function for automatically stopping an engine at a temporary stop. As shown in the figure, a hydraulic power steering apparatus 1 includes a steering shaft 3 to which a steering wheel 2 is fixed, a rack shaft 5 that reciprocates in the axial direction according to the rotation of the steering shaft 3, and a rack shaft 5 And a substantially cylindrical rack housing 6 which is inserted so as to be reciprocally movable. The steering shaft 3 is configured by connecting a column shaft 7, an intermediate shaft 8, and a pinion shaft 9 in this order from the steering wheel 2 side.

The rack shaft 5 and the pinion shaft 9 are disposed in the rack housing 6 with a predetermined crossing angle, and the rack teeth 5a formed on the rack shaft 5 and the pinion teeth 9a formed on the pinion shaft 9 are meshed with each other. Thus, the rack and pinion mechanism 11 is configured.
Further, tie rods 12 are connected to both ends of the rack shaft 5, and the tip of the tie rod 12 is connected to a knuckle (not shown) to which the steered wheels 13 are assembled. Therefore, in the hydraulic power steering apparatus 1, the rotation of the steering shaft 3 accompanying the steering operation is converted into the axial movement of the rack shaft 5 by the rack and pinion mechanism 11, and this axial movement is transmitted to the knuckle via the tie rod 12. Thus, the turning angle of the steered wheels 13, that is, the traveling direction of the vehicle is changed.

  The hydraulic power steering apparatus 1 also includes a hydraulic cylinder 21 as a hydraulic actuator that generates an assist force that assists the steering operation, and first and second electric pumps 22 and 23 that supply hydraulic oil to the hydraulic cylinder 21. ing. In addition, the hydraulic power steering device 1 stores hydraulic oil supplied to and discharged from the hydraulic cylinder 21 by the switching valve 24 that controls supply and discharge of hydraulic oil to the hydraulic cylinder 21 and the first and second electric pumps 22 and 23. The storage tank 25 is provided.

  The hydraulic cylinder 21 includes a cylindrical cylinder tube 31 constituted by a part of the rack housing 6. That is, the rack shaft 5 is inserted into the cylinder tube 31 so as to be able to reciprocate. The hydraulic cylinder 21 includes a piston 34 that divides the cylinder tube 31 into a first hydraulic chamber 32 and a second hydraulic chamber 33, and the piston 34 is fixed to the rack shaft 5 so as to be movable in the axial direction. Has been.

  As shown in FIG. 2, the first electric pump 22 includes a first motor 41 as a driving source, a first pump 42 that generates hydraulic pressure by being driven by the first motor 41, and an operation of the first motor 41. And a first ECU 43 for controlling the control. The second electric pump 23 includes a second motor 44 serving as a drive source, a second pump 45 that generates hydraulic pressure when driven by the second motor 44, and a second ECU 46 that controls the operation of the second motor 44. And. That is, in the present embodiment, the first and second ECUs 43 and 46 constitute a control device. As shown in FIG. 1, each suction port (not shown) of the first and second electric pumps 22 and 23 is connected to the storage tank 25 via a suction oil passage 47.

  The switching valve 24 is configured as a known rotary valve that controls supply and discharge of hydraulic oil to and from the first and second hydraulic chambers 32 and 33 of the hydraulic cylinder 21 in conjunction with the steering operation. Specifically, the switching valve 24 is provided with a supply port 51, a discharge port 52, and first and second supply / discharge ports 53 and 54. The supply port 51 is connected to the discharge ports (not shown) of the first and second electric pumps 22 and 23 via a supply oil passage 55 that branches into two branches on one end side. The discharge port 52 is connected to the storage tank 25 through a discharge oil passage 56. The first supply / discharge port 53 is connected to the first hydraulic chamber 32 via the first supply / discharge oil passage 57, and the second supply / discharge port 54 is connected to the first oil supply / discharge passage 58 via the second supply / discharge oil passage 58. 2 It is connected to the hydraulic chamber 33.

  In the hydraulic power steering apparatus 1 configured as described above, the hydraulic oil sucked up from the storage tank 25 by the first and second electric pumps 22 and 23 is supplied to the switching valve 24 via the supply oil passage 55. . Then, the hydraulic oil supplied to the switching valve 24 passes through one of the first and second oil supply / discharge passages 57 and 58 according to the driver's steering operation, and the first and second hydraulic chambers 32. , 33 is supplied. At this time, the hydraulic oil is discharged from the other one of the first and second hydraulic chambers 32 and 33, and this hydraulic oil is the other of the first and second supply / discharge oil passages 57 and 58, the switching valve 24 and the discharge oil passage. It is discharged to the storage tank 25 through 56. As a result, a hydraulic pressure difference is generated between the first hydraulic chamber 32 and the second hydraulic chamber 33, and the steering operation is assisted by the rack shaft 5 moving in the axial direction together with the piston 34 based on this hydraulic pressure difference. The

Next, the electrical configuration of the hydraulic power steering apparatus 1 will be described.
As shown in FIGS. 1 and 2, the first and second electric pumps 22 and 23 are connected to each other via a CAN (in-vehicle network) 61. A steering sensor 62 and a vehicle speed sensor 63 are connected to the CAN 61, and the steering angle θs and the vehicle speed v of the steering wheel 2 are transmitted. Further, the host ECU 64 is connected to the CAN 61, and the first and second ECUs 43 and 46 cooperate with each other on the basis of the respective state quantities obtained via the CAN 61, and the first and second electric pumps 22. , 23 (first and second motors 41, 44) can be controlled.

  Specifically, as shown in FIG. 2, the first ECU 43 includes a first microcomputer 71 (control means) that outputs a motor control signal, and a first power that supplies driving power to the first motor 41 based on the motor control signal. And a drive circuit 72. The second ECU 46 includes a second microcomputer 73 (control means) that outputs a motor control signal, and a second drive circuit 74 that supplies drive power to the second motor 44 based on the motor control signal. The first and second drive circuits 72 and 74 are connected to the same in-vehicle power source (battery) 75 mounted on the vehicle.

  The first and second drive circuits 72 and 74 have a pair of switching elements (for example, FETs) connected in series as a basic unit (switching arm) and are connected in parallel to each other. The motor control signal defines the on / off state (on-duty ratio) of each switching element. Then, the first and second drive circuits 72 and 74 supply drive power based on the on-duty ratio and the voltage of the in-vehicle power supply 75 indicated by the input motor control signal to the first and second motors 41 and 44, respectively. .

  The first microcomputer 71 detects a U-phase actual current value Iu1, a V-phase actual current value Iv1, and a W-phase actual current value Iw1 flowing through the first motor 41 (first electric pump 22). , 76v, 76w, and a first rotation angle sensor 77 for detecting a first rotation angle θ1 indicating the rotation angle of the first motor 41 is connected. On the other hand, the second microcomputer 73 detects a U-phase actual current value Iu2, a V-phase actual current value Iv2, and a W-phase actual current value Iw2 flowing through the second motor 44 (second electric pump 23). A sensor 78u, 78v, 78w and a second rotation angle sensor 79 for detecting a second rotation angle θ2 indicating the rotation angle of the second motor 44 are connected.

  The first and second microcomputers 71 and 73 detect each state quantity from each sensor at a predetermined sampling period, and receive each state quantity from the CAN 61. The first and second microcomputers 71 and 73 output motor control signals based on the acquired state quantities, thereby operating the first and second motors 41 and 44 through the supply of driving power. Control.

  Each control block shown below is realized by a computer program executed by the first and second microcomputers 71 and 73. The first and second microcomputers 71 and 73 detect the respective state quantities at a predetermined sampling period, and execute the respective arithmetic processes shown in the following control blocks for each predetermined period, thereby generating motor control signals. Generate.

Next, details of the function of the first microcomputer 71 will be described in detail with reference to FIG.
First, the first microcomputer 71 takes in the steering angle θs, the vehicle speed v, the first electric pump start command signal Sk1, and the second electric pump abnormality determination signal Sf2 transmitted from the CAN 61.
Then, the first microcomputer 71 transmits the first electric pump operating signal Sd1, the first electric pump abnormality determination signal Sf1, and the integrated state quantity transmission / reception signal Sm from the CAN 61 to the host ECU 64 and the second microcomputer 73.

  Next, the first microcomputer 71 differentiates the steering angle θs by the differentiator 101 to calculate the steering speed ωs. Subsequently, the first microcomputer 71 takes the steering speed ωs and the vehicle speed v into the first target speed command calculation unit 80. In the first target speed command calculation unit 80, a first map 81 for generating a first target speed command value ω1 * is composed of a steering speed ωs and a vehicle speed v. Here, as an example, the first map 81 is configured as shown in FIG. 6 (described later) from experimental values and the like.

  Next, the first microcomputer 71 inputs the first target speed command value ω <b> 1 * generated by the first target speed command calculation unit 80 to the subtracter 95. Further, the first microcomputer 71 differentiates the first rotation angle θ1 output from the first rotation angle sensor 77 of the first motor 41 by the differentiator 94 to generate the first rotation speed ω1. Then, the first microcomputer 71 inputs the first rotation speed ω <b> 1 generated by the differentiator 94 to the subtractor 95. Then, the first microcomputer 71 subtracts the first rotational speed ω1 from the first target speed command value ω1 * by the subtractor 95 to generate the first speed deviation Δω1.

  Next, the first microcomputer 71 inputs the generated first speed deviation Δω1 to the proportional control unit 82 of the first speed control. Then, the first microcomputer 71 is a proportional control unit 82 for the first speed control, and obtains the proportional state quantity Kp1v · Δω1 for the first speed control from the product of the first speed deviation Δω1 and the proportional gain Kp1v for the first speed control. Calculate and input to the adder 96. Further, the first microcomputer 71 inputs the generated first speed deviation Δω1 to the integral control unit 83 for the first speed control.

  The first microcomputer 71 uses the first speed control integral control unit 83 to calculate the first speed control integral state quantity Ki1v · ΣΔωk from the product of the first speed deviation Δω1 and the first speed control integral gain Ki1v. Calculate and input to the adder 96. Further, the first microcomputer 71 stores the calculated integrated state quantity Ki1v · ΣΔωk of the first speed control in the memory unit 84 (integrated state quantity storage means).

  Next, the first microcomputer 71 adds the proportional state quantity Kp1v · Δω1 of the first speed control and the integrated state quantity Ki1v · ΣΔωk of the first speed control by the adder 96, whereby the first q-axis current command value is obtained. Iq1 * is generated. Then, the first microcomputer 71 inputs the generated first q-axis current command value Iq1 * to the subtractor 97. The first microcomputer 71 then subtracts the first q-axis current value Iq1 from the first q-axis current command value Iq1 * by the subtractor 97 to generate a first q-axis current deviation ΔIq1.

Here, a method of generating the first q-axis current value Iq1 and the first d-axis current value Id1 will be described.
First, the first microcomputer 71 takes in the U-phase actual current value Iu1, the V-phase actual current value Iv1, and the W-phase actual current value Iw1 of the first electric pump 22 detected by the first current sensors 76u, 76v, and 76w. . Then, the first microcomputer 71 converts the captured U-phase actual current value Iu1, V-phase actual current value Iv1, and W-phase actual current value Iw1 into a first q-axis that is a two-phase current in the first d / q conversion calculation unit 91. A current value Iq1 and a first d-axis current value Id1 are generated.

  Next, the first microcomputer 71 inputs the generated first q-axis current deviation ΔIq1 to the proportional control unit 85 of the first q-axis current control. The first microcomputer 71 is a proportional control unit 85 for the first q-axis current control, and the proportional state quantity of the first q-axis current control is calculated from the product of the first q-axis current deviation ΔIq1 and the proportional gain Kp1qd of the first q-axis current control. Kp1qd · ΔIq1 is calculated and input to the adder 98.

  Further, the first microcomputer 71 inputs the generated first q-axis current deviation ΔIq1 to the integration controller 86 for the first q-axis current control. Then, the first microcomputer 71 is an integration control unit 86 for the first q-axis current control. From the product of the first q-axis current deviation ΔIq1 and the integration gain Ki1qd for the first q-axis current control, the first q-axis current control integration state quantity is obtained. Ki1qd · ΣΔIqk is calculated and input to the adder 98. Further, the first microcomputer 71 stores the calculated integration state quantity Ki1qd · ΣΔIqk of the first q-axis current control in the memory unit 87 (integration state quantity storage means).

  Next, the first microcomputer 71 adds the proportional state quantity Kp1qd · ΔIq1 of the first q-axis current control and the integrated state quantity Ki1qd · ΣΔIqk of the first q-axis current control to generate the first q-axis voltage command value Vq1 *. And input to the first d / q inverse transform calculation unit 92.

  On the other hand, the first microcomputer 71 sets the first d-axis current command value Id1 * to zero and inputs it to the subtractor 99. The first microcomputer 71 then subtracts the first d-axis current value Id1 from the first d-axis current command value Id1 * by the subtractor 95 to generate a first d-axis current deviation ΔId1.

  Next, the first microcomputer 71 inputs the generated first d-axis current deviation ΔId1 to the proportional control unit 88 for the first d-axis current control. The first microcomputer 71 is a proportional control unit 88 for the first d-axis current control, and the proportional state quantity of the first d-axis current control is calculated from the product of the first d-axis current deviation ΔId1 and the proportional gain Kp1dd of the first d-axis current control. Kp1dd · ΔId1 is calculated and input to the adder 100.

  Further, the first microcomputer 71 inputs the generated first d-axis current deviation ΔId1 to the integration controller 89 for the first d-axis current control. Then, the first microcomputer 71 is an integration control unit 89 for the first d-axis current control. From the product of the first d-axis current deviation ΔId1 and the integration gain Ki1dd for the first d-axis current control, the first d-axis current control integration state quantity is obtained. Ki1dd · ΣΔIdk is calculated and input to the adder 100. Further, the first microcomputer 71 stores the calculated integration state quantity Ki1dd · ΣΔIdk of the first d-axis current control in the memory unit 90 (integration state quantity storage means).

  Next, the first microcomputer 71 adds the proportional state quantity Kp1dd · ΔId1 of the first d-axis current control and the integrated state quantity Ki1dd · ΣΔIdk of the first d-axis current control to generate the first d-axis voltage command value Vd1 *. And input to the first d / q inverse transform calculation unit 92.

  Next, the first microcomputer 71 determines the first phase voltage command value Vu1 * from the first q-axis voltage command value Vq1 * and the first d-axis voltage command value Vd1 * input to the first d / q inverse conversion calculation unit 92. , Vv1 *, Vw1 * are generated and input to the first PWM output unit 93. Then, the first microcomputer 71 outputs a motor control signal from the first PWM output unit 93 to the first drive circuit 72.

  The first microcomputer 71 constitutes an inter-microcomputer state quantity transmission / reception unit 102. The first microcomputer 71 determines the abnormality of the first motor 41 based on the U-phase actual current value Iu1, the V-phase actual current value Iv1, the W-phase actual current value Iw1, and the first rotation angle θ1 of the first electric pump 22. I do. Then, the first microcomputer 71 transmits a first electric pump abnormality determination signal Sf1 indicating the result of the abnormality determination to the CAN 61 via the inter-microcomputer state quantity transmission / reception unit 102. Is stopped, and the first motor 41 is stopped. In addition, as a method of abnormality determination, for example, when the U-phase actual current value Iu1, the V-phase actual current value Iv1, and the W-phase actual current value Iw1 of the first electric pump 22 become values that cannot be taken, It is possible to adopt various methods such as determining that there is an abnormality when the first rotation angle θ1 does not change in spite of being supplied.

  In addition, the first microcomputer 71 uses the inter-microcomputer state quantity transmission / reception unit 102 as an integration state quantity transmission / reception signal Sm as the integration state quantity transmission / reception signal Sm. To the host ECU 64 and the second microcomputer 73. Further, the first microcomputer 71 receives the first electric pump activation command signal Sk1 and the second electric pump abnormality determination signal Sf2 via the inter-microcomputer state quantity transmission / reception unit 102.

Next, details of the function of the second microcomputer 73 will be described in detail with reference to FIG.
The function of the second microcomputer 73 is almost the same as the function of the first microcomputer 71.
First, the second microcomputer 73 takes in the steering angle θs, the vehicle speed v, the second electric pump start command signal Sk2, the first electric pump abnormality determination signal Sf1, and the integrated state quantity transmission / reception signal Sm transmitted from the CAN 61. Then, the second microcomputer 73 transmits the second electric pump operating signal Sd2 and the second electric pump abnormality determination signal Sf2 from the CAN 61 to the host ECU 64 and the first microcomputer 71.

  Next, the second microcomputer 73 differentiates the steering angle θs by the differentiator 131 to calculate the steering speed ωs. Subsequently, the second microcomputer 73 takes the steering speed ωs and the vehicle speed v into the second target speed command calculation unit 110. In the second target speed command calculation unit 110, a second map 111 for generating the second target speed command value ω2 * is configured from the steering speed ωs and the vehicle speed v. Here, as an example, the second map 111 is configured as shown in FIG. 6 (described later) from experimental values and the like.

  Next, the second microcomputer 73 inputs the second target speed command value ω2 * generated by the second target speed command calculation unit 110 to the subtractor 125. Further, the second microcomputer 73 differentiates the second rotation angle θ2 output from the second rotation angle sensor 79 of the second motor 44 by the differentiator 124 to generate a second rotation speed ω2. Then, the second microcomputer 73 inputs the second rotation speed ω <b> 2 generated by the differentiator 124 to the subtractor 125. Then, the second microcomputer 73 subtracts the second rotational speed ω2 from the second target speed command value ω2 * by the subtractor 125 to generate a second speed deviation Δω2.

  Next, the second microcomputer 73 inputs the generated second speed deviation Δω2 to the proportional control unit 112 of the second speed control. Then, the second microcomputer 73 is a proportional control unit 112 for the second speed control, and calculates the proportional state quantity Kp2v · Δω2 for the second speed control from the product of the second speed deviation Δω2 and the proportional gain Kp2v for the second speed control. Calculate and input to the adder 126. Further, the second microcomputer 73 inputs the generated second speed deviation Δω2 to the integration control unit 113 for the second speed control.

  Then, the second microcomputer 73 uses the second speed control integral control unit 113 to calculate the second speed control integral state quantity Ki2v · ΣΔωk from the product of the second speed deviation Δω2 and the second speed control integral gain Ki2v. Calculate and input to the adder 126. Further, the second microcomputer 73 stores the calculated integration state quantity Ki2v · ΣΔωk of the second speed control in the memory unit 114 (integration state quantity storage means).

  Next, the second microcomputer 73 adds the proportional state quantity Kp2v · Δω2 of the second speed control and the integrated state quantity Ki2v · ΣΔωk of the second speed control to generate the second q-axis current command value Iq2 *. . Then, the second microcomputer 73 inputs the generated second q-axis current command value Iq2 * to the subtractor 127. Then, the second microcomputer 73 subtracts the second q-axis current value Iq2 from the second q-axis current command value Iq2 * by the subtractor 127 to generate a second q-axis current deviation ΔIq2.

Here, a method of generating the second q-axis current value Iq2 and the second d-axis current value Id2 will be described.
First, the second microcomputer 73 takes in the U-phase actual current value Iu2, the V-phase actual current value Iv2, and the W-phase actual current value Iw2 of the second electric pump 23 detected by the second current sensors 78u, 78v, and 78w. . Then, the second microcomputer 73 converts the captured U-phase actual current value Iu2, V-phase actual current value Iv2, and W-phase actual current value Iw2 into a second q-axis that is a two-phase current in the second d / q conversion calculation unit 121. A current value Iq2 and a second d-axis current value Id2 are generated.

  Next, the second microcomputer 73 inputs the generated second q-axis current deviation ΔIq2 to the proportional control unit 115 of the second q-axis current control. Then, the second microcomputer 73 is a proportional control unit 115 for the second q-axis current control, and the proportional state quantity of the second q-axis current control is calculated from the product of the second q-axis current deviation ΔIq2 and the proportional gain Kp2qd of the second q-axis current control. Kp2qd · ΔIq2 is calculated and input to the adder 128.

  Further, the second microcomputer 73 inputs the generated second q-axis current deviation ΔIq2 to the integration controller 116 for the second q-axis current control. Then, the second microcomputer 73 is an integration control unit 116 for the second q-axis current control. From the product of the second q-axis current deviation ΔIq2 and the integration gain Ki2qd for the second q-axis current control, an integration state quantity for the second q-axis current control is obtained. Ki2qd · ΣΔIqk is calculated and input to the adder 128. Further, the second microcomputer 73 stores the calculated integration state quantity Ki2qd · ΣΔIqk of the second q-axis current control in the memory unit 117 (integration state quantity storage means).

  Next, the second microcomputer 73 adds the proportional state quantity Kp2qd · ΔIq2 of the second q-axis current control and the integrated state quantity Ki2qd · ΣΔIqk of the second q-axis current control to generate the second q-axis voltage command value Vq2 *. And input to the second d / q inverse transform operation unit 122.

  On the other hand, the second microcomputer 73 sets the second d-axis current command value Id2 * to zero and inputs it to the subtractor 129. Then, the second microcomputer 73 subtracts the second d-axis current value Id2 from the second d-axis current command value Id2 * by the subtractor 129 to generate a second d-axis current deviation ΔId2.

  Next, the second microcomputer 73 inputs the generated second d-axis current deviation ΔId2 to the proportional control unit 118 of the second d-axis current control. Then, the second microcomputer 73 is a proportional control unit 118 for the second d-axis current control. From the product of the second d-axis current deviation ΔId2 and the proportional gain Kp2dd for the second d-axis current control, the proportional state quantity of the second d-axis current control is obtained. Kp2dd · ΔId2 is calculated and input to the adder 130.

  Further, the second microcomputer 73 inputs the generated second d-axis current deviation ΔId2 to the integration control unit 119 for second d-axis current control. Then, the second microcomputer 73 is an integration control unit 119 for the second d-axis current control. From the product of the second d-axis current deviation ΔId2 and the integration gain Ki2dd for the second d-axis current control, an integration state quantity for the second d-axis current control is obtained. Ki2dd · ΣΔIdk is calculated and input to the adder 130. Further, the second microcomputer 73 stores the calculated integration state quantity Ki2dd · ΣΔIdk of the second d-axis current control in the memory unit 120 (integration state quantity storage means).

  Next, the second microcomputer 73 adds the proportional state quantity Kp2dd · ΔId2 of the second d-axis current control and the integrated state quantity Ki2dd · ΣΔIdk of the second d-axis current control to generate the second d-axis voltage command value Vd2 *. And input to the second d / q inverse transform operation unit 122.

  Next, the second microcomputer 73 calculates the second phase voltage command value Vu2 * from the second q-axis voltage command value Vq2 * and the second d-axis voltage command value Vd2 * input to the second d / q inverse conversion calculation unit 122. , Vv2 *, Vw2 * are generated and input to the second PWM output unit 123. Then, the second microcomputer 73 outputs a motor control signal from the second PWM output unit 123 to the second drive circuit 74.

  The second microcomputer 73 constitutes an inter-microcomputer state quantity transmission / reception unit 132. Similar to the first microcomputer 71, the second microcomputer 73 is based on the U-phase actual current value Iu2, the V-phase actual current value Iv2, the W-phase actual current value Iw2, and the second rotation angle θ2 of the second electric pump 23. Then, abnormality determination of the second motor 44 is performed. Then, the second microcomputer 73 transmits a second electric pump abnormality determination signal Sf2 indicating the result of the abnormality determination to the CAN 61 via the inter-microcomputer state quantity transmission / reception unit 132, and when an abnormality is detected, the drive power Is stopped, and the second motor 44 is stopped. In addition, as a method of abnormality determination, for example, when the U-phase actual current value Iu2, the V-phase actual current value Iv2, and the W-phase actual current value Iw2 of the second electric pump 23 become values that cannot be taken, It is possible to adopt various methods such as determining that there is an abnormality when the second rotation angle θ2 does not change in spite of supplying

  Further, the second microcomputer 73 transmits and receives the integration state quantity stored from the memory units 84, 87, and 90, which are the integration state quantity storage means of the first microcomputer 71, via the inter-microcomputer state quantity transmission / reception unit 132. After being input as the signal Sm, it is written into the memory units 114, 117, 120, which are integral state quantity storage means of the second microcomputer 73. Further, the second microcomputer 73 receives the second electric pump activation command signal Sk2 and the first electric pump abnormality determination signal Sf1 via the inter-microcomputer state quantity transmission / reception unit 132.

  The above describes the function when the host ECU 64 outputs the first electric pump start command signal Sk1 and the second electric pump start command signal Sk2 to the first and second electric pumps 22 and 23 simultaneously. However, in the present embodiment, even when the second electric pump 23 is operated behind the operation of the first electric pump 22, the operating state of the first electric pump 22 and the operation of the second electric pump 23 are Describes measures to improve steering feeling, making the state the same.

A control procedure of the first and second electric pumps when the second electric pump 23 is operated after the first electric pump 22 is operated will be described in detail with reference to FIG.
The first microcomputer 71 determines whether or not the second electric pump operating signal Sd2 is on (step S101). When the second electric pump operating signal Sd2 is not on (step S101: NO), the first microcomputer 71 determines whether or not the initial setting flag F is “0” (step S102). When the initial setting flag F is “0” (step S102: YES), the first microcomputer 71 further determines whether or not the first electric pump operating signal Sd1 is on. (Step S103).

  Then, when the first electric pump operating signal Sd1 is on (step S103: YES), the first microcomputer 71 determines that the first electric pump is already operating, and performs the first speed control. The integrated state quantity Ki1v · ΣΔωk of the first speed control output from the integration control unit 83 is stored in the memory unit 84 (step S104).

  Subsequently, the first microcomputer 71 stores the integration state quantity Ki1qd · ΣΔIqk of the first q-axis current control output from the integration control unit 86 of the first q-axis current control in the memory unit 87 (step S105). Further, the first microcomputer 71 stores the integration state quantity Ki1dd · ΣΔIdk of the first d-axis current control output from the integration control unit 89 of the first d-axis current control in the memory unit 90 (step S106). Then, the first microcomputer 71 determines that the integrated state quantities of all the control units have been stored, and sets the initial setting flag F (F ← “1”, step S107).

  Next, the second microcomputer 73 determines whether or not the second electric pump start command signal Sk2 is on (step S108). Then, when the second electric pump start command signal Sk2 is on (step S108: YES), the second microcomputer 73 activates the second electric pump 23 with a delay from the operation of the first electric pump 22. The first speed control integration state amount Ki1v · ΣΔωk read from the memory unit 84 is written to the memory unit 114 of the second speed control integration control unit 113 (step S109). Further, the second microcomputer 73 writes the integration state quantity Ki1qd · ΣΔIqk of the first q-axis current control read from the memory unit 87 into the memory unit 117 of the integration control unit 116 of the second q-axis current control (step S110).

  Subsequently, the second microcomputer 73 writes the integration state quantity Ki1dd · ΣΔIdk of the first d-axis current control read from the memory unit 90 to the memory unit 120 of the integration control unit 119 of the second d-axis current control (step S111). Then, the second microcomputer 73 starts the operation of the second electric pump (step S112), resets the initial setting flag F (F ← “0”, step S113), and ends the process.

  On the other hand, when the second electric pump start command signal Sk2 is not on (step S108: NO), the second microcomputer 73 activates the second electric pump 23 with a delay from the operation of the first electric pump 22. After determining that it is not in the state and resetting the initial setting flag F (F ← “0”, step S113), the process is terminated. The first microcomputer 71 determines that the first electric pump operating signal Sd1 is not on (step S103: NO), the initial setting flag F is not “0” (step S102: NO), or the second electric pump. If the in-operation signal Sd2 is on (step S101: YES), the process ends without doing anything.

Next, a map in the target speed command value calculation unit of the first and second microcomputers will be described with reference to FIG.
In FIG. 6, the horizontal axis represents the steering speed (deg / sec), the vertical axis represents the target rotational speed (rev / min), and the vehicle speed v.

  The target rotational speed ω * varies depending on the steering speed ωs and the vehicle speed v. In general, the lower the vehicle speed v, the larger the target rotational speed ω *. In this embodiment, the vehicle speed v is obtained from experimental values at 0 km / h, 40 km / h, 80 km / h, and 120 km / h, but interpolation may be performed during that time. In addition, the map figure of this embodiment changes with vehicle models, and may be adapted each time.

Next, the operation and effect of the control device for the hydraulic power steering apparatus of the present embodiment configured as described above will be described.
Control means for controlling the operation of the hydraulic actuator through supply of driving power to the motor, the control means includes a speed feedback control unit having a proportional element and an integral element, a current feedback control unit having a proportional element and an integral element, and a speed An integration state quantity storage means for storing the integration state quantity of the feedback control unit and the integration state quantity of the current feedback control unit, the control means being delayed from the operation of the first electric pump, When operating the electric pump, the integrated state quantity of the speed feedback control unit of the first electric pump and the integrated state quantity of the current feedback control unit are read from the integrated state quantity storage means, and the speed of the second electric pump After tracing to the integrated state quantity storage means of the feedback control unit and the current feedback control unit, the operation of the second electric pump It was configured to start.

  According to the above configuration, the integral state quantity of the speed feedback control unit that drives the first electric pump and the integral state quantity of the current feedback control unit, which greatly affect the control performance of the electric pump, are continuously stored. When the second electric pump is operated later than the operation of the first electric pump, the integration state quantity of the speed feedback control unit of the first electric pump and the integration state quantity of the current feedback control unit are integrated. Reading from the state quantity storage means and tracing to the integrated state quantity storage means of the speed feedback control unit and current feedback control unit of the second electric pump. As a result, the integrated state quantity of the first electric pump and the integrated state quantity of the second electric pump, which have a great influence on the control performance of the electric pump, are the same, so that the steering feeling can be improved.

In addition, the said embodiment can also be implemented in the following aspects which changed this suitably.
In this embodiment, the integral state quantity of the speed feedback control unit that drives the first electric pump and the integral state quantity of the current feedback control unit are constantly stored, and after the operation of the first electric pump, In the case of operating the second electric pump, the second electric pump is driven with the stored integrated state quantity of the speed feedback control unit that drives the first electric pump and the integrated state quantity of the current feedback control unit. The integrated state quantity of the speed feedback control unit and the integrated state quantity of the current feedback control unit are traced.
However, the state quantity to be stored is not limited to the integral state quantity, and a proportional state quantity, a differential state quantity, or the like may be stored and traced.

In the present embodiment, the first and second electric pumps 22 and 23 are provided as the hydraulic pressure source of the hydraulic cylinder 21, but three or more electric pumps may be provided.

In the present embodiment, the first and second electric pumps 22 and 23 have the first and second ECUs 43 and 46, respectively. However, the present invention is not limited to this. The operation of the motors 41 and 44 may be controlled.

1: Hydraulic power steering device, 2: Steering wheel,
3: Steering shaft, 5: Rack shaft, 5a: Rack teeth,
6: rack housing, 7: column shaft, 8: intermediate shaft, 9: pinion shaft,
9a: Pinion teeth, 11: Rack and pinion mechanism, 12: Tie rod,
13: steered wheel, 21: hydraulic cylinder, 22: first electric pump, 23: second electric pump, 24: switching valve, 25: storage tank, 31: cylinder tube, 32: first hydraulic chamber,
33: second hydraulic chamber, 34: piston, 41: first motor, 42: first pump,
43: first ECU, 44: second motor, 45: second pump, 46: second ECU,
47: intake oil passage, 51: supply port, 52: discharge port, 53: first supply / discharge port,
54: second supply / discharge port, 55: supply oil passage, 56: discharge oil passage, 57: first supply / discharge oil passage,
58: second oil supply / discharge passage, 61: CAN, 62: steering sensor, 63: vehicle speed sensor, 64: host ECU, 71: first microcomputer (control means), 72: first drive circuit,
73: second microcomputer (control means), 74: second drive circuit,
75: In-vehicle power supply (battery),
76u, 76v, 76w: first current sensor, 77: first rotation angle sensor,
78u, 78v, 78w: second current sensor, 79: second rotation angle sensor,
80: 1st target speed command calculating part, 81: 1st map,
82: Proportional control part of the first speed control,
83: the integral control unit of the first speed control,
84, 87, 90: memory unit (integrated state quantity storage means),
85: Proportional control unit for first q-axis current control, 86: Integration control unit for first q-axis current control,
88: Proportional control unit for first d-axis current control, 89: Integration control unit for first d-axis current control,
91: first d / q conversion operation unit, 92: first d / q inverse conversion operation unit,
93: First PWM output unit,
95, 97, 99: subtractor, 96, 98, 100: adder, 94: first differentiator,
101, 131: differentiator,
102, 132: state quantity transmitter / receiver between microcomputers,
110: second target speed command calculation unit, 111: second map,
112: proportional control unit of second speed control,
113: the integral control unit of the second speed control,
114, 117, 120: memory unit (integrated state quantity storage means),
115: Proportional control unit for second q-axis current control, 116: Integration control unit for second q-axis current control,
118: Proportional control unit for second d-axis current control, 119: Integration control unit for second d-axis current control,
121: second d / q conversion operation unit, 122: second d / q inverse conversion operation unit,
123: second PWM output unit, 124: second differentiator,
125, 127, 129: subtractor, 126, 128, 130: adder,
θs: steering angle, ωs: steering speed, v: vehicle speed,
Sk1: first electric pump start command signal, Sk2: second electric pump start command signal,
Sd1: first electric pump operating signal, Sd2: second electric pump operating signal,
Sf1: first electric pump abnormality determination signal, Sf2: second electric pump abnormality determination signal,
Sm: Integration state quantity transmission / reception signal,
θ1: first rotation angle,
ω1 *: first target speed command value, ω1: first rotation speed, Δω1: first speed deviation,
Iu1: U-phase actual current value of the first electric pump,
Iv1: V-phase actual current value of the first electric pump,
Iw1: W-phase actual current value of the first electric pump,
Kp1v: proportional gain of the first speed control, Ki1v: integral gain of the first speed control,
Kp1v · Δω1: proportional state quantity of the first speed control,
Ki1v · ΣΔωk: integrated state quantity of the first speed control,
Iq1 *: first q-axis current command value, Iq1: first q-axis current value,
ΔIq1: First q-axis current deviation,
Kp1qd: proportional gain of the first q-axis current control,
Ki1qd: integral gain of the first q-axis current control,
Kp1qd · ΔIq1: proportional state quantity of the first q-axis current control,
Ki1qd · ΣΔIqk: the integrated state quantity of the first q-axis current control,
Id1 *: first d-axis current command value, Id1: first d-axis current value,
ΔId1: first d-axis current deviation,
Kp1dd: proportional gain of the first d-axis current control,
Ki1dd: integral gain of the first d-axis current control,
Kp1dd · ΔId1: proportional state quantity of the first d-axis current control,
Ki1dd · ΣΔIdk: integrated state quantity of the first d-axis current control,
Vq1 *: first q-axis voltage command value, Vd1 *: first d-axis voltage command value,
Vu1 *, Vv1 *, Vw1 *: first phase voltage command value,
θ2: second rotation angle,
ω2 *: second target speed command value, ω2: second rotational speed, Δω2: second speed deviation,
Iu2: U-phase actual current value of the second electric pump,
Iv2: V-phase actual current value of the second electric pump,
Iw2: W-phase actual current value of the second electric pump,
Kp2v: proportional gain of the second speed control, Ki2v: integral gain of the second speed control,
Kp2v · Δω2: proportional state quantity of the second speed control,
Ki2v · ΣΔωk: integral state quantity of the second speed control,
Iq2 *: second q-axis current command value, Iq2: second q-axis current value,
ΔIq2: Second q-axis current deviation,
Kp2qd: proportional gain of second q-axis current control,
Ki2qd: integral gain of second q-axis current control,
Kp2qd · ΔIq2: proportional state quantity of second q-axis current control,
Ki2qd · ΣΔIqk: the amount of integration state of the second q-axis current control,
Id2 *: second d-axis current command value, Id2: second d-axis current value,
ΔId2: second d-axis current deviation,
Kp2dd: proportional gain of second d-axis current control,
Ki2dd: integral gain of second d-axis current control,
Kp2dd · ΔId2: proportional state quantity of the second d-axis current control,
Ki2dd · ΣΔIdk: integral state quantity of second d-axis current control,
Vq2 *: second q-axis voltage command value, Vd2 *: second d-axis voltage command value,
Vu2 *, Vv2 *, Vw2 *: Second phase voltage command value,
F: Initial setting flag

Claims (1)

In a control device for a hydraulic power steering apparatus including first and second electric pumps for supplying hydraulic oil to a hydraulic actuator that generates an assist force for assisting a steering operation in a steering system using a motor as a drive source,
Control means for controlling the operation of the hydraulic actuator through supply of driving power to the motor;
The control means includes a speed feedback control unit having a proportional element and an integral element;
A current feedback control unit having a proportional element and an integral element;
An integration state quantity storage means for storing the integration state quantity of the speed feedback control unit and the integration state quantity of the current feedback control unit;
When the control means operates the second electric pump later than the operation of the first electric pump, the control means integrates the state quantity of the speed feedback control unit of the first electric pump and the current. The integration state quantity of the feedback control unit is read from the integration state quantity storage means, traced to the integration state quantity storage means of the speed feedback control unit and the current feedback control unit of the second electric pump, and then the second state. Starting the operation of the electric pump of the
A control device for a hydraulic power steering device.

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