Control method for dragging engine to stop at target position by permanent magnet synchronous motor

Abstract

The invention discloses a control method for dragging an engine to stop at a target position by a permanent magnet synchronous motor. The method comprises the following steps: S1, controlling the motor to operate in a shutdown process; s2, calculating an electrical angle corresponding to 0 degree of a machine; s3, the current actual position of the motor is calculated based on reconstruction and integration of the electrical angle in the rotation process of the motor; s4, calculating the electrical angle deviation between the current position and the target position when the trigger control is enabled; s5, performing differential processing based on the electrical angle deviation, and then performing PI control to obtain a deviation rotating speed; and S6, superposing the deviation rotating speed on the basis of the set rotating speed, outputting a target rotating speed, calculating the deviation between the current position of the motor and the target position, updating the target rotating speed according to the angle deviation, and stopping the engine at the target position through rotating speed control. According to the control method for dragging the engine to stop at the target position by the permanent magnet synchronous motor provided by the invention, the effects of minimum torque and better NVH when the engine is started can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid vehicle manufacturing, and in particular to a control method for stopping an engine at a target position by driving a permanent magnet synchronous motor. Background Art

[0002] With the global emphasis on sustainable development and environmental protection, the new energy vehicle industry is developing rapidly, especially pure electric vehicles and extended-range electric vehicles. As the core component of new energy vehicles, the technology of permanent magnet synchronous motors is constantly innovating to meet the growing market demand.

[0003] As the core component of extended-range electric vehicles, the range extender is mainly composed of an engine and a permanent magnet synchronous motor. The permanent magnet synchronous motor is used to drag the engine to stop at the target position to ensure the minimum starting torque of the range extender and better NVH performance. Summary of the invention

[0004] In view of the above problems, a control method for a permanent magnet synchronous motor to drive an engine to stop at a target position is provided, aiming to solve the problems existing in the prior art.

[0005] The specific technical solutions are as follows:

[0006] A control method for a permanent magnet synchronous motor to drive an engine to stop at a target position, the method comprising the following steps:

[0007] S1, control the motor to run during the shutdown process;

[0008] S2, calculate the electrical angle corresponding to mechanical 0 degrees;

[0009] S3, reconstructing and integrating the electrical angle during the motor rotation process to calculate the current actual position of the motor;

[0010] S4, when trigger control is enabled, calculate the electrical angle deviation between the current position and the target position;

[0011] S5, performing differential processing based on the electrical angle deviation, and then performing PI control to obtain the deviation speed;

[0012] S6. Superimpose the deviation speed on the set speed, output the target speed, and adjust the speed.

[0013] The above-mentioned control method of using a permanent magnet synchronous motor to drive an engine to stop at a target position also has the following feature: step S1 further includes the following calculation method:

[0014] T=J*ΔV+P*ΔV+∫ΔVdt

[0015] Where, T: motor load torque;

[0016] J: motor moment of inertia;

[0017] ΔV: speed deviation;

[0018] P1: scale parameter;

[0019] dt: unit time.

[0020] The above-mentioned control method of the permanent magnet synchronous motor driving the engine to stop at the target position also has the following characteristics: the specific calculation method in step S2 is:

[0021] angPhyZero=atan2(sinCor, cosCor)

[0022] Where, angPhyZero: the electrical angle corresponding to mechanical 0 degrees;

[0023] sinCor: resolver signal sin amplitude;

[0024] cosCor: resolver signal cos amplitude.

[0025] The above-mentioned control method of the permanent magnet synchronous motor driving the engine to stop at the target position also has the following characteristics: the specific calculation method in step S3 is:

[0026] angElcClb=angElc-angPhyZero

[0027] Where, angElcClb: reconstructed electrical angle;

[0028] angElc: motor electrical angle;

[0029] angPhyZero: The electrical angle corresponding to mechanical 0 degrees.

[0030] The above-mentioned control method of using a permanent magnet synchronous motor to drive an engine to stop at a target position also has the following characteristics: the step S4 further includes the following steps:

[0031] S41, calculate the target electrical angle of the motor running clockwise:

[0032] When the target pole pair number is greater than or equal to the current pole pair number:

[0033] angRef=(poleRef-polePost)*2*pi+(angStpRef-angElcClb)

[0034] When the target number of pole pairs is less than the current number of pole pairs:

[0035] angRef=(poleMot-polePost+poleRef)*2*pi+(angStpRef-angElcClb)

[0036] Where, angRef: target electrical angle;

[0037] poleMot: number of motor pole pairs;

[0038] polePost: the current pole pair number after electrical angle reconstruction;

[0039] poleRef: target pole pair number when the motor stops;

[0040] pi: pi;

[0041] angStpRef: target electrical angle when the motor stops;

[0042] angElcClb: electrical angle after reconstruction.

[0043] S42, calculate the target electrical angle of the motor running counterclockwise:

[0044] When the target pole pair number is greater than or equal to the current pole pair number:

[0045] angRef=(poleRef-polePost)*2*pi+(angElcClb-angStpRef)

[0046] When the target number of pole pairs is less than the current number of pole pairs:

[0047] angRef=(poleMot-polePost+poleRef)*2*pi+(angElcClb-angStpRef)

[0048] Where, angRef: target electrical angle;

[0049] poleMot: number of motor pole pairs;

[0050] polePost: the current pole pair number after electrical angle reconstruction;

[0051] poleRef: target pole pair number when the motor stops;

[0052] pi: pi;

[0053] angStpRef: target electrical angle when the motor stops;

[0054] angElcClb: electrical angle after reconstruction.

[0055] The above-mentioned control method of using a permanent magnet synchronous motor to drive an engine to stop at a target position also has the following characteristics: the step S5 further includes the following steps:

[0056] S51, differentiate the target electrical angle:

[0057] angDiff=angSpdCtrlRef-angRef

[0058] Where, angDiff: angle differential angle difference

[0059] angSpdCtrlRef: angle setting value when control is enabled;

[0060] angRef: target electrical angle.

[0061] S52, PI control of the differential angle difference:

[0062] spdDiff=P*angDiff+∫angDiffdt

[0063] Where, spdDiff: speed adjustment value;

[0064] angDiff: angle differential angle difference;

[0065] P2: scale parameter;

[0066] dt: unit time.

[0067] The above-mentioned control method of the permanent magnet synchronous motor driving the engine to stop at the target position also has the following characteristics: the specific calculation method in step S6 is:

[0068] spdRef=SpdCtrlRef-spdDiff

[0069] Where, spdRef: target speed;

[0070] SpdCtrlRef: speed setting value when control is enabled;

[0071] spdDiff: speed adjustment value.

[0072] In summary, the beneficial effects of this scheme are:

[0073] In the control method for stopping an engine at a target position by a permanent magnet synchronous motor provided by the present invention, the deviation between the current position of the motor and the target position is calculated, the target speed is updated according to the angle deviation, and the engine is stopped at the target position by speed control. The control method for stopping an engine at a target position by a permanent magnet synchronous motor provided by the present invention can achieve the effect of minimum torque and better NVH when the engine is started. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 This is a schematic diagram of a control method for using a permanent magnet synchronous motor to drive an engine to stop at a target position as described in the present invention. DETAILED DESCRIPTION

[0075] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0076] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0077] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited thereto.

[0078] In the accompanying drawings, Figure 1 The schematic diagram of the control method of the permanent magnet synchronous motor driving the engine to stop at the target position recorded in the present invention is as follows: Figure 1 As shown, the control method of the permanent magnet synchronous motor driving the engine to stop at the target position provided in this embodiment includes the following steps:

[0079] S1, control the motor to run during the shutdown process;

[0080] S2, calculate the electrical angle corresponding to mechanical 0 degrees;

[0081] S3, reconstructing and integrating the electrical angle during the motor rotation process to calculate the current actual position of the motor;

[0082] S4, when trigger control is enabled, calculate the electrical angle deviation between the current position and the target position;

[0083] S5, performing differential processing based on the electrical angle deviation, and then performing PI control to obtain the deviation speed;

[0084] S6, superimposing the deviation speed on the set speed, outputting the target speed, and adjusting the speed. In the above embodiment, step S1 also includes the following calculation method:

[0085] T=J*△V+P*△V+∫△Vdt

[0086] Where, T: motor load torque;

[0087] J: motor moment of inertia;

[0088] ΔV: speed deviation;

[0089] P1: scale parameter;

[0090] dt: unit time.

[0091] It should be noted that the motor's rotational inertia is determined by measurement activities, and the proportional parameter P1 is a coefficient determined under the optimal state of the motor and obtained through testing. The calculation formula for the speed deviation is target speed - actual speed.

[0092] The above-mentioned control method of the permanent magnet synchronous motor driving the engine to stop at the target position also has the following characteristics: the specific calculation method in step S2 is:

[0093] angPhyZero=atan2(sinCor,cosCor)

[0094] Where, angPhyZero: the electrical angle corresponding to mechanical 0 degrees;

[0095] sinCor: resolver signal sin amplitude;

[0096] cosCor: resolver signal cos amplitude.

[0097] In the above embodiment, the specific calculation method in step S3 is:

[0098] angElcClb=angElc-angPhyZero

[0099] Where, angElcClb: reconstructed electrical angle;

[0100] angElc: motor electrical angle;

[0101] angPhyZero: The electrical angle corresponding to mechanical 0 degrees.

[0102] The above-mentioned control method of using a permanent magnet synchronous motor to drive an engine to stop at a target position also has the following characteristics: step S4 further includes the following steps:

[0103] S41, calculate the target electrical angle of the motor running clockwise:

[0104] When the target pole pair number is greater than or equal to the current pole pair number:

[0105] angRef=(poleRef-polePost)*2*pi+(angStpRef-angElcClb)

[0106] When the target number of pole pairs is less than the current number of pole pairs:

[0107] angRef=(poleMot-polePost+poleRef)*2*pi+(angStpRef-angElcClb)

[0108] Where, angRef: target electrical angle;

[0109] poleMot: number of motor pole pairs;

[0110] polePost: the current pole pair number after electrical angle reconstruction;

[0111] poleRef: target pole pair number when the motor stops;

[0112] pi: pi;

[0113] angStpRef: target electrical angle when the motor stops;

[0114] angElcClb: electrical angle after reconstruction.

[0115] S42, calculate the target electrical angle of the motor running counterclockwise:

[0116] When the target pole pair number is greater than or equal to the current pole pair number:

[0117] angRef=(poleRef-polePost)*2*pi+(angElcClb-angStpRet)

[0118] When the target number of pole pairs is less than the current number of pole pairs:

[0119] angRef=(poleMot-polePost+poleRef)*2*pi+(angElcClb-angStpRet)

[0120] Where, angRef: target electrical angle;

[0121] poleMot: number of motor pole pairs;

[0122] polePost: the current pole pair number after electrical angle reconstruction;

[0123] poleRef: target pole pair number when the motor stops;

[0124] pi: pi;

[0125] angStpRef: target electrical angle when the motor stops;

[0126] angElcClb: electrical angle after reconstruction.

[0127] In the above embodiment, step S5 also includes the following steps:

[0128] 851. Differentiate the target electrical angle:

[0129] angDiff=angSpdCtrlRef-angRef

[0130] Where, angDiff: angle differential angle difference

[0131] angSpdCtrlRef: angle setting value when control is enabled;

[0132] angRef: target electrical angle.

[0133] S52, PI control of the differential angle difference:

[0134] spdDiff=P*angDiff+∫angDiffdt

[0135] Where, spdDiff: speed adjustment value;

[0136] angDiff: angle differential angle difference;

[0137] P2: scale parameter;

[0138] dt: unit time.

[0139] It should be noted that the proportional parameter P2 is a coefficient determined under the optimal state of the motor and is obtained through testing.

[0140] It should also be noted that the angle setting value when the control is enabled is a value determined when the motor is in the optimal state. The value varies depending on the motor. The value range is 0-2π. In the test, the value is 0.5π when the motor is in the optimal state.

[0141] In the above embodiment, the specific calculation method in step S6 is:

[0142] spdRef=SpdCtrlRef-spdDiff

[0143] Where, spdRef: target speed;

[0144] SpdCtrlRef: speed setting value when control is enabled;

[0145] spdDiff: speed adjustment value.

[0146] It should be noted that the speed setting value when the control is enabled is a value determined when the motor is in the optimal state. The value varies depending on the motor. In the test, the value is 500rpm when the motor is in the optimal state.

[0147] It should also be noted that the optimal state of the motor means that the motor starting force is small and the Nvh effect is the best.

[0148] Working principle: when the speed reaches 1000rpm, it enters the adjustment process. When the speed drops to 500rpm, the cylinder stop control starts. The time is t1. During the time period from t1 to t2, the fixed speed is maintained and the coarse adjustment process is performed. The coarse adjustment process can quickly cover a large angle. During the time period from t2 to t3, the target speed is calculated through the speed deviation, and the fine adjustment process is performed to gradually reduce the speed to cover the remaining small angle until it stops at the target position at t3.

[0149] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for a permanent magnet synchronous motor to drive an engine to stop at a target position, characterized in that: The method comprises the following steps: S1, control the motor to run during the shutdown process; S2, calculate the electrical angle corresponding to mechanical 0 degrees; S3, reconstructing and integrating the electrical angle during the motor rotation process to calculate the current actual position of the motor; S4, when trigger control is enabled, calculate the electrical angle deviation between the current position and the target position; S5, performing differential processing based on the electrical angle deviation, and then performing PI control to obtain the deviation speed; S6. Superimpose the deviation speed on the set speed, output the target speed, and adjust the speed.

2. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 1, characterized in that: The step S1 also includes the following calculation method: T=J*△V+P*△V+∫△Vdt Where, T: motor load torque; J: motor moment of inertia; △V: speed deviation; P1: scale parameter; dt: unit time.

3. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 2, characterized in that: The specific calculation method in step S2 is: angPhyZero=atan2(sinCor,cosCor) Where, angPhyZero: the electrical angle corresponding to mechanical 0 degrees; sinCor: resolver signal sin amplitude; cosCor: resolver signal cos amplitude.

4. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 3, characterized in that: The specific calculation method in step S3 is: angElcClb=angElc-angPhyZero Where, angElcClb: reconstructed electrical angle; angElc: motor electrical angle; angPhyZero: The electrical angle corresponding to mechanical 0 degrees.

5. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 4, characterized in that: The step S4 further comprises the following steps: S41, calculate the target electrical angle of the motor running clockwise: When the target pole pair number is greater than or equal to the current pole pair number: angRef=(poleRef-polePost)*2*pi+(angStpRef-angElcClb) When the target number of pole pairs is less than the current number of pole pairs: angRef=(poleMot-polePost+poleRef)*2*pi+(angStpRef-angElcClb) Where, angRef: target electrical angle; poleMot: number of motor pole pairs; polePost: the current pole pair number after electrical angle reconstruction; poleRef: target pole pair number when the motor stops; pi: pi; angStpRef: target electrical angle when the motor stops; angElcClb: electrical angle after reconstruction. S42, calculate the target electrical angle of the motor running counterclockwise: When the target pole pair number is greater than or equal to the current pole pair number: angRef=(poleRef-polePost)*2*pi+(angElcClb-angStpRef) When the target number of pole pairs is less than the current number of pole pairs: angRef=(poleMot-polePost+poleRef)*2*pi+(angElcClb-angStpRef) Wherein, angRef: target electrical angle; poleMot: number of motor pole pairs; polePost: the current pole pair number after electrical angle reconstruction; poleRef: target pole pair number when the motor stops; pi: pi; angStpRef: target electrical angle when the motor stops; angElcClb: electrical angle after reconstruction.

6. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 5, characterized in that: The step S5 also includes the following steps: S51. Differentiate the target electrical angle: angDiff=angSpdCtrlRef-angRef Where, angDiff: angle differential angle difference angSpdCtrlRef: angle setting value when control is enabled; angRef: target electrical angle. S52, perform PI control on the differential angle difference: spdDiff=P*angDiff+∫angDiffdt Where, spdDiff: speed adjustment value; angDiff: angle differential angle difference; P2: scale parameter; dt: unit time.

7. The control method of a permanent magnet synchronous motor driving an engine to stop at a target position according to claim 6, characterized in that: The specific calculation method in step S6 is: spdRef=SpdCtrlRef-spdDiff Where, spdRef: target speed; SpdCtrlRef: speed setting value when control is enabled; spdDiff: speed adjustment value.

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