CN110758376A - Control method, control device and vehicle for dual-planetary hybrid power system - Google Patents

Abstract

The invention relates to a control method, a control device and a vehicle of a double planetary hybrid power system. The method includes: the control method includes: calculating the engine stop demand torque curve according to the fastest engine stop speed curve; according to the MT motor speed and the engine set speed, combined with the leverage relationship of the dual-planetary hybrid power system, calculate the ISG motor setting. Determine the speed, and calculate the ISG motor speed regulation demand torque curve according to the set speed of the ISG motor and the actual speed of the ISG motor; according to the battery charging power limit, the motor recovery power and the ISG motor characteristics, calculate the negative of the ISG motor power generation torque limited by the system. The maximum value; in the negative maximum value of the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the system-limited ISG motor generation torque, take a larger value for each control time point, so as to obtain the setting of the ISG motor torque curve.

Description

Control method, control device and vehicle for dual-planetary hybrid power system

technical field

The invention belongs to the field of hybrid vehicles, and in particular relates to a control method, a control device and a vehicle of a dual-planetary hybrid power system.

Background technique

There is a dual-planetary hybrid power system, the structure of which is shown in Figure 1. The system includes an engine 1, a first motor 2, a second motor 3, a planetary row I4 and a planetary row II5. The connection relationship of each component in the system is as follows : The rotor shaft of the first motor 2 is connected to the sun gear 41 of the planetary row I4, the sun gear 51 of the planetary row II5 is connected to the rotor shaft of the second motor 3, the engine 1 is connected to the planetary carrier 42 of the planetary row I4, and the planetary row I4 The ring gear 43 is connected with the planet carrier 52 of the planet row II5 and the system output shaft 6 in sequence. In the above-mentioned dual-planetary hybrid power system, there are two elements that can be used as power sources, namely the engine 1 or the second motor 3, and the first motor 2 is used to drive the engine 1 to start when the engine 1 starts, and the engine 1 needs Tow engine 1 when stopped. In this system, the second motor 3 is referred to as an MT motor, and the first motor 2 is referred to as an ISG motor.

In the process of stopping engine 1, in order to prevent the inertial moment of engine 1 from causing severe vibration of the whole vehicle, the ISG motor is generally used to stop engine 1. In the process of stopping engine 1 by the ISG motor, the torque setting of the ISG motor is more important. Both too large and too small will have adverse effects, for example, when the torque setting of the ISG motor is too large, it may cause the drag engine 1 to reverse, and when the torque setting of the ISG motor is too small, it will lead to low recovery energy, thus Not conducive to the economy of the vehicle. Therefore, how to reasonably control the torque of the ISG motor is an urgent problem that needs to be solved in the process of the ISG motor towing the engine.

SUMMARY OF THE INVENTION

The purpose of the present invention is to at least solve the problem of reasonably controlling the torque of the ISG motor during the process of the ISG motor towing the engine. This purpose is achieved through the following technical solutions:

A first aspect of the present invention provides a control method for a dual-planetary hybrid power system, characterized in that the control method includes:

Calculate the torque curve of engine shutdown demand according to the fastest engine shutdown speed curve;

According to the speed of the MT motor and the set speed of the engine, combined with the leverage relationship of the dual-planetary hybrid power system, the set speed of the ISG motor is calculated, and the torque curve of the speed regulation demand of the ISG motor is calculated according to the set speed of the ISG motor and the actual speed of the ISG motor ;

Calculate the negative maximum value of the ISG motor generating torque defined by the system according to the battery charging power limit, the motor recovery power and the ISG motor characteristics;

In the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque limited by the system, take a larger value for each control time point, so as to obtain the set torque curve of the ISG motor;

The torque of the ISG motor is controlled according to the set torque curve of the ISG motor.

According to the control method of the dual-planetary hybrid power system according to the embodiment of the present invention, among the three of the engine stop demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque defined by the system, for each of the three Take the larger value at the control time point (because the three are all negative values, so the larger value is the one with the smallest absolute value), so as to obtain the set torque curve of the ISG motor, which takes into account the fastest engine speed. The shutdown speed curve, the structure of the dual-planetary hybrid power system, the working conditions and characteristics of the engine, the MT motor and the ISG motor, the battery charging power limit, the motor recovery power and many other factors, therefore, a better comprehensive control effect can be achieved. Therefore, the control method in the embodiment of the present invention can relatively reasonably control the torque of the ISG motor during the process of the ISG motor to stop the engine.

In some embodiments of the present invention, the control method further includes:

Obtain the real-time torque of the ISG motor and the real-time speed of the engine;

Calculate the time required to complete the torque clearance based on the real-time torque;

Comparing the real-time speed with the curve of the fastest stopping speed of the engine to obtain the estimated stopping time;

Calculate the time difference according to the estimated downtime and the time required to complete the torque clearance;

comparing the duration difference with a preset duration threshold;

According to the result that the duration difference is less than or equal to a preset duration threshold, the ISG motor is controlled to perform clearing.

In some embodiments of the present invention, the control method further includes:

Set the fastest engine stop speed curve according to the engine operating conditions.

In some embodiments of the present invention, the parameters of the engine operating conditions include at least engine oil temperature and exhaust braking conditions.

In some embodiments of the present invention, the control method further includes:

PID calculation is performed on the set speed of the ISG motor and the actual speed of the ISG motor to obtain the torque curve of the speed regulation demand of the ISG motor.

A second aspect of the present invention provides a control device for a dual-planetary hybrid power system, comprising:

The calculation module is used to calculate the torque curve of the engine shutdown demand according to the fastest engine shutdown speed curve; the calculation module is also used to calculate the ISG according to the MT motor speed and the engine set speed, combined with the leverage relationship of the dual-planetary hybrid power system The motor set speed, and calculate the ISG motor speed regulation demand torque curve according to the ISG motor set speed and the ISG motor actual speed; the calculation module is also used to calculate the system according to the battery charging power limit, the motor recovery power and the ISG motor characteristics The negative maximum value of the limited ISG motor generating torque;

The comparison module is used for taking the maximum value of each control time point in the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque limited by the system, so as to obtain the ISG motor's maximum value. Set the torque curve;

The control module is configured to control the torque of the ISG motor according to the set torque curve of the ISG motor.

In some embodiments of the present invention, the control device further includes a measurement module, and the measurement module is configured to acquire the real-time torque of the ISG motor and the real-time rotational speed of the engine;

The calculation module is also used to calculate the time required for the completion of the torque clearance based on the real-time torque, and calculate the time length difference according to the estimated downtime duration and the time required for the completion of the torque clearance;

The comparison module is further configured to compare the real-time rotational speed and the fastest engine shutdown rotational speed curve, obtain an estimated shutdown duration, and compare the duration difference with a preset duration threshold;

The control module is further configured to control the ISG motor to clear the torque according to the result that the difference in the duration is less than or equal to a preset duration threshold.

In some embodiments of the present invention, the calculation module is further configured to set the fastest engine shutdown speed curve according to the engine operating conditions.

A third aspect of the present invention proposes a vehicle, comprising:

A two-planetary hybrid powertrain; and

The control device of the dual-planetary hybrid power system in any of the above embodiments.

In some embodiments of the present invention, the dual-planetary-row hybrid power system includes: an engine, a first motor, a second motor, a planetary row I and a planetary row II, and the rotor shaft of the first motor is connected to the planetary row The sun gear of I is connected, the sun gear of the planetary row II is connected to the rotor shaft of the second motor, the engine is connected to the planet carrier of the planetary row I, and the ring gear of the planetary row I is connected to the rotor shaft of the second motor. The planet carrier of planet row II and the system output shaft are connected in turn.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. Also, the same components are denoted by the same reference numerals throughout the drawings. In the attached image:

1 is a schematic diagram of a dual-planetary hybrid power system of a vehicle according to an embodiment of the present invention;

2 is a flowchart of a control method of a dual-planetary hybrid power system according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a control device of a dual-planetary hybrid power system according to an embodiment of the present invention.

Detailed ways

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be more thoroughly understood, and will fully convey the scope of the present disclosure to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" can also be intended to include the plural forms unless the context clearly dictates otherwise. The terms "comprising", "comprising", "containing" and "having" are inclusive and thus indicate the presence of stated features, steps, operations, elements and/or components, but do not preclude the presence or addition of one or Various other features, steps, operations, elements, components, and/or combinations thereof.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be restricted by these terms. These terms may only be used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.

For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature to another element or feature as shown in the figures, such as "inner", "outer", "inner" ", "outside", "below", "below", "above", "above", etc. This spatially relative term is intended to include different orientations of the device in use or operation other than the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "above the other elements or features" above features". Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in FIG. 2 , an embodiment of the first aspect of the present invention provides a control method for a dual-planetary hybrid power system, and the control method includes:

Calculate the torque curve of engine shutdown demand according to the fastest engine shutdown speed curve;

According to the speed of the MT motor and the set speed of the engine, combined with the leverage relationship of the dual-planetary hybrid power system, the set speed of the ISG motor is calculated, and the torque curve of the speed regulation demand of the ISG motor is calculated according to the set speed of the ISG motor and the actual speed of the ISG motor ;

Calculate the negative maximum value of the ISG motor generating torque defined by the system according to the battery charging power limit, the motor recovery power and the ISG motor characteristics;

In the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque limited by the system, take a larger value for each control time point, so as to obtain the set torque curve of the ISG motor;

The torque of the ISG motor is controlled according to the set torque curve of the ISG motor.

According to the control method of the dual-planetary hybrid power system according to the embodiment of the present invention, among the three of the engine stop demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque defined by the system, for each of the three Take the larger value at the control time point (because the three are all negative values, so the larger value is the one with the smallest absolute value), so as to obtain the set torque curve of the ISG motor, which takes into account the fastest engine speed. The shutdown speed curve, the structure of the dual-planetary hybrid power system, the working conditions and characteristics of the engine, the MT motor and the ISG motor, the battery charging power limit, the motor recovery power and many other factors, therefore, a better comprehensive control effect can be achieved. Therefore, the control method in the embodiment of the present invention can relatively reasonably control the torque of the ISG motor during the process of the ISG motor to stop the engine.

It should be noted that the fastest engine stop speed curve can be calculated and obtained according to the engine oil temperature, exhaust brake and other conditions. Make the system more economical.

In some embodiments of the present invention, the control method further includes:

Obtain the real-time torque of the ISG motor and the real-time speed of the engine;

Calculate the time required to complete the torque clearance based on the real-time torque;

Comparing the real-time speed with the curve of the fastest stopping speed of the engine to obtain the estimated stopping time;

Calculate the time difference according to the estimated downtime and the time required to complete the torque clearance;

comparing the duration difference with a preset duration threshold;

According to the result that the duration difference is less than or equal to a preset duration threshold, the ISG motor is controlled to perform clearing.

If you wait until the engine speed drops to 0 and then clear the torque of the ISG motor, since the torque reduction needs to be completed within a period of time, this will cause the torque of the ISG motor to drag the engine to reverse after the engine speed is 0. Therefore, It is very important to control the timing of the clearance to prevent the engine from being reversed.

In this embodiment, the time required to complete the torque clearance is calculated according to the real-time torque of the ISG motor, the estimated stop duration is calculated according to the real-time engine speed and the curve of the fastest stopping speed of the engine, and then the estimated stop duration and the torque clearance required to complete the calculation are obtained. If the difference between the durations is greater than or equal to the preset duration threshold, the ISG motor is controlled to clear the torque, which can ensure that the engine speed is close to 0 but has not yet dropped to 0 when the torque clearance is completed. Under the premise of economy, the engine will not be reversed by reverse drag.

In some embodiments of the present invention, the control method further includes:

PID calculation is performed on the set speed of the ISG motor and the actual speed of the ISG motor to obtain the torque curve of the speed regulation demand of the ISG motor.

As shown in FIG. 3 , an embodiment of the second aspect of the present invention provides a control device 100 for a dual-planetary hybrid power system, which includes:

The calculation module 10 is used to calculate the torque curve of the engine shutdown demand according to the fastest engine shutdown speed curve; the calculation module is also used to calculate the torque curve according to the speed of the MT motor and the set speed of the engine, in combination with the leverage relationship of the dual-planetary hybrid power system. ISG motor set speed, and calculate the ISG motor speed regulation demand torque curve according to the ISG motor set speed and the ISG motor actual speed; the calculation module is also used to calculate according to the battery charging power limit, the motor recovery power and the ISG motor characteristics The negative maximum value of the ISG motor generating torque limited by the system;

The comparison module 20 is configured to perform a large operation for each control time point in the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque defined by the system, so as to obtain the ISG motor The set torque curve of ;

The control module 30 is configured to control the torque of the ISG motor according to the set torque curve of the ISG motor.

In some embodiments of the present invention, the control device further includes a measurement module 40, and the measurement module 40 is configured to acquire the real-time torque of the ISG motor and the real-time rotational speed of the engine;

The calculation module 10 is also used to calculate the time required to complete the torque clearance based on the real-time torque, and calculate the time difference according to the estimated downtime duration and the time required to complete the torque clearance;

The comparison module 20 is further configured to compare the real-time rotational speed with the fastest engine shutdown rotational speed curve, obtain an estimated shutdown duration, and compare the duration difference with a preset duration threshold;

The control module 30 is further configured to control the ISG motor to perform clearing according to the result that the difference in the duration is less than or equal to a preset duration threshold.

In some embodiments of the present invention, the calculation module 10 is further configured to set the fastest engine shutdown speed curve according to the engine operating conditions.

An embodiment of the third aspect of the present invention provides a vehicle, comprising:

A dual-planetary hybrid power system; and the control device of the dual-planetary hybrid power system in any of the above embodiments.

In some embodiments of the present invention, the dual-planetary-row hybrid power system includes: an engine, a first motor, a second motor, a planetary row I and a planetary row II, and the rotor shaft of the first motor is connected to the planetary row The sun gear of I is connected, the sun gear of the planetary row II is connected to the rotor shaft of the second motor, the engine is connected to the planet carrier of the planetary row I, and the ring gear of the planetary row I is connected to the rotor shaft of the second motor. The planet carrier of planet row II and the system output shaft are connected in turn.

The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Substitutions should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. a control method for a dual-planetary hybrid power system, characterized in that the control method comprises: Calculate the torque curve of engine shutdown demand according to the fastest engine shutdown speed curve; According to the speed of the MT motor and the set speed of the engine, combined with the leverage relationship of the dual-planetary hybrid power system, the set speed of the ISG motor is calculated, and the torque curve of the speed regulation demand of the ISG motor is calculated according to the set speed of the ISG motor and the actual speed of the ISG motor ; Calculate the negative maximum value of the ISG motor generating torque defined by the system according to the battery charging power limit, the motor recovery power and the ISG motor characteristics; In the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque limited by the system, take a larger value for each control time point, so as to obtain the set torque curve of the ISG motor; The torque of the ISG motor is controlled according to the set torque curve of the ISG motor. 2. The control method of the dual-planetary hybrid power system according to claim 1, wherein the control method further comprises: Obtain the real-time torque of the ISG motor and the real-time speed of the engine; Calculate the time required to complete the torque clearance based on the real-time torque; Comparing the real-time speed with the curve of the fastest stopping speed of the engine to obtain the estimated stopping time; Calculate the time difference according to the estimated downtime and the time required to complete the torque clearance; comparing the duration difference with a preset duration threshold; According to the result that the duration difference is less than or equal to a preset duration threshold, the ISG motor is controlled to perform clearing. 3. The control method of the dual-planetary hybrid power system according to claim 1, wherein the control method further comprises: Set the fastest engine stop speed curve according to the engine operating conditions. 4 . The control method for a dual-planetary hybrid power system according to claim 3 , wherein the parameters of the engine operating conditions at least include engine oil temperature and exhaust braking conditions. 5 . 5. The control method of the dual-planetary hybrid power system according to claim 1, wherein the control method further comprises: PID calculation is performed on the set speed of the ISG motor and the actual speed of the ISG motor to obtain the torque curve of the speed regulation demand of the ISG motor. 6. A control device for a double planetary hybrid power system, characterized in that, comprising: The calculation module is used to calculate the torque curve of the engine shutdown demand according to the fastest engine shutdown speed curve; the calculation module is also used to calculate the ISG according to the MT motor speed and the engine set speed, combined with the leverage relationship of the dual-planetary hybrid power system The motor set speed, and calculate the ISG motor speed regulation demand torque curve according to the ISG motor set speed and the ISG motor actual speed; the calculation module is also used to calculate the system according to the battery charging power limit, the motor recovery power and the ISG motor characteristics The negative maximum value of the limited ISG motor generating torque; The comparison module is used for taking the maximum value of each control time point in the engine shutdown demand torque curve, the ISG motor speed regulation demand torque curve and the negative maximum value of the ISG motor power generation torque limited by the system, so as to obtain the ISG motor's maximum value. Set the torque curve; The control module is configured to control the torque of the ISG motor according to the set torque curve of the ISG motor. 7 . The control device of the dual-planetary hybrid power system according to claim 6 , wherein the control device further comprises a measurement module, and the measurement module is used to obtain the real-time torque of the ISG motor and the real-time torque of the engine. 8 . Rotating speed; The calculation module is also used to calculate the time required for the completion of the torque clearance based on the real-time torque, and calculate the time length difference according to the estimated downtime duration and the time required for the completion of the torque clearance; The comparison module is further configured to compare the real-time rotational speed and the fastest engine shutdown rotational speed curve, obtain an estimated shutdown duration, and compare the duration difference with a preset duration threshold; The control module is further configured to control the ISG motor to clear the torque according to the result that the difference in the duration is less than or equal to a preset duration threshold. 8 . The control device of the dual-planetary hybrid power system according to claim 6 , wherein the calculation module is further configured to set the fastest engine shutdown speed curve according to the engine operating conditions. 9 . 9. A vehicle, characterized in that, comprising: A two-planetary hybrid powertrain; and The control device of a dual-planetary hybrid power system according to any one of claims 6 to 8. 10. The vehicle according to claim 9, wherein the dual-planetary hybrid power system comprises: an engine, a first motor, a second motor, a planetary I and a planetary II, and the rotor of the first motor The shaft is connected with the sun gear of the planetary row I, the sun gear of the planetary row II is connected with the rotor shaft of the second motor, the engine is connected with the planet carrier of the planetary row I, and the planetary row I The ring gear is connected with the planet carrier of the planet row II and the system output shaft in turn.

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