CN111810630A - A control system and control method suitable for hydraulic coupling transmission - Google Patents

Abstract

The invention provides a control system and a control method suitable for a hydraulically coupled transmission, including an automatic transmission electronic control system and an automatic transmission hydraulic system; the automatic transmission hydraulic system includes an oil pump, an oil supply system, a gear shifting system and a hydraulic system. Torque converter lockup and cooling management system, the automatic transmission electronic control system includes sensors, TCU and solenoid valves. The control system and control strategy of the hydraulically coupled transmission in the present invention can realize real-time communication between the engine and the transmission, ensure that the input speed, torque and gear position of the engine meet the needs of the vehicle operation, and at the same time, it can also actively adjust according to the driver's wishes. The operation state of the transmission, and ensure that the automatic transmission can work according to the predetermined optimal control law under any working conditions to achieve the optimal shifting quality and transmission efficiency.

Description

A control system and control method suitable for hydraulic coupling transmission

technical field

The invention belongs to the technical field of automatic transmissions, and in particular relates to a control system and a control method suitable for a hydraulic coupling type transmission.

Background technique

At present, the domestic automatic transmission is developing very rapidly. As a new type of automatic transmission, the hydro-mechanical dual-clutch transmission consists of a torque converter and a dual-clutch transmission. The gear shifting of the dual-clutch transmission is realized through the cooperation of the two clutches and the control of the clutch actuator and the shift actuator to realize the shift without power interruption, and its transmission principle is similar to that of the AMT transmission. The transmission mechanism is mostly mechanical transmission. The cooperation of the clutch makes the shifting speed faster than that of AMT, so it has higher power and fuel economy. However, the structure of the dual-clutch transmission is relatively complex, and there are many control units. If the control strategy is not properly coordinated, the dual-clutch transmission will have a very serious frustration during the shifting process, and even double-gear will occur, resulting in the vehicle unable to drive normally. Therefore, a good control strategy of the dual clutch transmission is particularly important.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a control system and control method suitable for the hydraulic coupling type transmission, so as to achieve the optimal shifting quality and transmission efficiency.

In order to achieve the above object, the technical solution adopted in the present invention is: a control system suitable for a hydraulic coupling type transmission, including an automatic transmission electronic control system and an automatic transmission hydraulic system;

The automatic transmission hydraulic system includes an oil pump, an oil supply system, a shifting system, and a torque converter locking and cooling management system. The inlet of the oil supply system is connected to the oil pump, and the outlet of the oil supply system is respectively connected to the shifting system and the cooling system. The torque converter locking and cooling management system, the input end of the shift system is also connected with a shift lever, and the output end of the shift system is connected to the transmission synchronizer through the shift actuator;

The automatic transmission electronic control system includes a sensor, a TCU and a solenoid valve, wherein the sensor includes a vehicle speed sensor and an accelerator opening sensor, both of which are connected to the input end of the TCU, and the solenoid valve includes a main oil circuit solenoid valve. , shift solenoid valve and lock control solenoid valve, input ends of main oil circuit solenoid valve, shift solenoid valve and lock control solenoid valve are all connected to the output end of TCU, main oil circuit solenoid valve, shift solenoid valve The output ends of the valve and the locking control solenoid valve are respectively connected to the control ends of the oil supply system, the shifting system and the torque converter locking and cooling management system;

Further, a torque converter cooler is connected to the output end of the torque converter locking and cooling management system.

Further, the torque converter lock-up and cooling management system includes a torque converter lock-up clutch, a turbine speed sensor, a pump wheel speed sensor, an oil pressure sensor and a hydraulic oil temperature sensor. The speed sensor, the pump wheel speed sensor, the oil pressure sensor and the hydraulic oil temperature sensor are all connected to the input end of the TCU, and the torque converter lock-up clutch is connected to the output end of the TCU. Analysis and processing of parameters, active control of torque converter lock-up clutch state, to achieve optimal fuel economy.

A control method for a control system of a hydraulically coupled transmission, comprising the following steps:

S1. Determine the current state of the torque converter;

S2. If it is in a locked state, determine whether it is in a braking state, if it is in a braking state, execute unlocking; if it is in an unlocked state, execute step S3;

S3. Determine the current gear, if the gear is neutral or shifting, maintain the current state;

S4. If it is in the gear position, judge the hydraulic oil temperature T;

S5. If T < 60°C, maintain the current state; if T > 60°C, the TCU judges the current rotational speed of the turbine and pump wheel through the torque converter lockup and cooling management system;

S6. If the current rotational speed nw>the preset rotational speed nb, maintain the current state, and if nw<nb, execute the locking operation.

Compared with the prior art, the beneficial effects of the present invention are: the control system and control strategy of the hydraulically coupled transmission in the present invention can realize real-time communication between the engine and the transmission, and ensure that the input speed, torque and transmission gear of the engine meet the requirements of vehicle operation conditions. At the same time, it can actively adjust the transmission operating state according to the driver's wishes, and ensure that the automatic transmission can work according to the predetermined optimal control law under any working conditions to achieve the optimal shifting quality and transmission efficiency.

Description of drawings

Fig. 1 is a principle block diagram of a control system of the present invention suitable for a hydraulically coupled transmission;

FIG. 2 is a schematic flowchart of a control method of a control system suitable for a hydraulic coupling transmission according to the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are the present invention. Part of the embodiments of the invention, but not all of the embodiments, based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

A control system suitable for hydraulic coupling transmission, including automatic transmission electronic control system and automatic transmission hydraulic system;

The automatic transmission hydraulic system includes an oil pump, an oil supply system, a shifting system, and a torque converter locking and cooling management system. The inlet of the oil supply system is connected to the oil pump, and the outlet of the oil supply system is respectively connected to the shifting system and the cooling system. The torque converter locking and cooling management system, the input end of the shift system is also connected with a shift lever, and the output end of the shift system is connected to the transmission synchronizer through the shift actuator;

The automatic transmission electronic control system includes a sensor, a TCU and a solenoid valve, wherein the sensor includes a vehicle speed sensor and an accelerator opening sensor, both of which are connected to the input end of the TCU, and the solenoid valve includes a main oil circuit solenoid valve. , shift solenoid valve and lock control solenoid valve, input ends of main oil circuit solenoid valve, shift solenoid valve and lock control solenoid valve are all connected to the output end of TCU, main oil circuit solenoid valve, shift solenoid valve The output ends of the valve and the locking control solenoid valve are respectively connected to the control ends of the oil supply system, the shifting system and the torque converter locking and cooling management system;

To further optimize the solution, a torque converter cooler is connected to the output end of the torque converter locking and cooling management system.

To further optimize this solution, the torque converter lock-up and cooling management system includes a torque converter lock-up clutch, a turbine speed sensor, a pump wheel speed sensor, an oil pressure sensor and a hydraulic oil temperature sensor. The lock-up clutch , turbine speed sensor, pump wheel speed sensor, oil pressure sensor and hydraulic oil temperature sensor are all connected to the input end of the TCU, and the torque converter lock-up clutch is connected to the output end of the TCU. The analysis and processing of various parameters of the torque converter actively control the state of the torque converter lock-up clutch to achieve the optimal fuel economy.

A control method for a control system of a hydraulically coupled transmission, characterized in that it comprises the following steps:

S1. Determine the current state of the torque converter;

S2. If it is in a locked state, determine whether it is in a braking state, if it is in a braking state, execute unlocking; if it is in an unlocked state, execute step S3;

S3. Determine the current gear, if the gear is neutral or shifting, maintain the current state;

S4. If it is in the gear position, judge the hydraulic oil temperature T;

S5. If T < 60°C, maintain the current state; if T > 60°C, the TCU judges the current rotational speed of the turbine and pump wheel through the torque converter lockup and cooling management system;

S6. If the current rotational speed nw>the preset rotational speed nb, maintain the current state, and if nw<nb, execute the locking operation.

The present invention is described in detail below in conjunction with the accompanying drawings:

As shown in Figure 1, a control system suitable for a hydraulic coupling transmission includes an automatic transmission electronic control system and an automatic transmission hydraulic system;

The automatic transmission hydraulic system includes an oil pump, an oil supply system, a shifting system, and a torque converter locking and cooling management system. The inlet of the oil supply system is connected to the oil pump, and the outlet of the oil supply system is respectively connected to the shifting system and the cooling system. The torque converter locking and cooling management system, the input end of the shift system is also connected with a shift lever, and the output end of the shift system is connected to the transmission synchronizer through the shift actuator;

The automatic transmission electronic control system includes a sensor, a TCU and a solenoid valve, wherein the sensor includes a vehicle speed sensor and an accelerator opening sensor, both of which are connected to the input end of the TCU, and the solenoid valve includes a main oil circuit solenoid valve. , shift solenoid valve and lock control solenoid valve, input ends of main oil circuit solenoid valve, shift solenoid valve and lock control solenoid valve are all connected to the output end of TCU, main oil circuit solenoid valve, shift solenoid valve The output ends of the valve and the locking control solenoid valve are respectively connected to the control ends of the oil supply system, the shifting system and the torque converter locking and cooling management system;

The automatic transmission hydraulic system can control the oil supply of the oil pump to meet the hydraulic pressure and the minimum flow required for the shifting operation, the hydraulic torque converter and the lubrication, and at the same time, it can ensure the corresponding pressure required for the normal operation of the hydraulic system. .

The shifting system has the function of shifting operation and emergency protection. The automatic shifting function means that the driver operates the manual shift lever and then triggers the shift valve. The TCU controls the shift solenoid valve based on the information received and the current working conditions of the vehicle. Switches to realize automatic shifting operation through the collection and separation of clutches and brakes in the oil pressure control shifting system.

The emergency support function is used to ensure that when there is a problem with the electronic control system of the vehicle or the solenoid valve fails, the vehicle still maintains one or two forward gears and reverse gears. The driver manually controls the shift valve to make the electronic control system fail. able to continue driving.

The torque converter lock-up and cooling management system includes torque converter lock-up clutch, turbine speed sensor, pump wheel speed sensor, oil pressure sensor and hydraulic oil temperature sensor. The analysis and processing of each parameter actively controls the state of the torque converter lock-up clutch to achieve the optimal fuel economy.

The torque converter lock-up and cooling management system ensures the normal operating temperature of the torque converter. When the temperature of the oil in the torque converter is too low, the viscosity of the oil is high, and the working efficiency of the torque converter is low. Temperature rise; when the temperature of the oil in the torque converter is too high, the control system controls the lock-up clutch to forcibly lock, and the cooling system intervenes at the same time to take away the heat of the oil in time to ensure that the temperature of the oil is always at the torque converter. Temperature range for maximum operating efficiency.

The mechanical structure of the hydraulic coupling transmission to which the present invention is applicable mainly includes two parts, a hydraulic torque converter and a dual clutch transmission. Control is also a control for both. For the torque converter, it is mainly locked according to the vehicle engine speed, turbine speed, water temperature, oil temperature, gear, brake, accelerator opening and other signals. The control process is shown in Figure 2. Include the following steps:

S1. Determine the current state of the torque converter;

S2. If it is in a locked state, determine whether it is in a braking state, if it is in a braking state, execute unlocking; if it is in an unlocked state, execute step S3;

S3. Determine the current gear, if the gear is neutral or shifting, maintain the current state;

S4. If it is in the gear position, judge the hydraulic oil temperature T;

S5. If T < 60°C, maintain the current state; if T > 60°C, the TCU judges the current rotational speed of the turbine and pump wheel through the torque converter lockup and cooling management system;

S6. If the current speed nw > the preset speed nb in the TCU, maintain the current state, and if nw<nb, execute the locking operation.

When the vehicle is in the low-speed gear and the starting stage, the low-speed gear is generally in the traction condition. At this time, the vehicle bears a large load. In order to adapt the vehicle power system to the high-strength external load, the torque converter lockup clutch should be Put it in the unlocked state.

The high-speed gear of the vehicle is generally the driving condition. When the vehicle is in the driving gear, the load on the vehicle is not too large. After the shift is completed and the vehicle is in a stable driving state, the torque converter is locked to improve fuel economy. performance and mechanical transmission efficiency.

When the torque converter hydraulic oil temperature is lower than 60 degrees Celsius, the viscosity of the oil is high, and the torque converter efficiency is low. At this time, the torque converter lock-up clutch should be in a forced unlock state, and the torque converter is used to stir the hydraulic pressure. The oil can quickly reach the appropriate temperature and ensure the working performance of the torque converter.

During the braking operation, the engine will generate an anti-drag torque on the driving wheels through the transmission, which will affect the braking effect. When the gear does not match the speed of the vehicle, for example: the gear is too high and the speed is too low, the vehicle engine will Was suffocated to extinguish. Therefore, in the case of braking operation, the lock-up clutch should be in the unlocked state.

Shifting conditions include upshifts and downshifts. During the shifting process, whether it is an upshift operation or a downshift operation, there will be shocks during the process. At this time, the torque converter lock-up clutch should be in the unlocked state, so as to give full play to the torque converter's ability to absorb shocks. effect.

The dual-clutch transmission consists of an electronic control system and various actuators. Among them, the electronic control system is mainly composed of a speed sensor, an oil temperature sensor, a solenoid valve, a TCU, and a wiring harness. The actuators include shift actuators and clutch actuators. The function of the TCU is to ensure that the relationship between the sliding friction power and the impact degree is balanced during the shifting operation of the dual clutch, thereby prolonging the service life of the clutch friction plates and improving the fuel economy.

During the dual clutch shifting process, although the engine speed is the same as the transmission shaft speed, the engine torque will be positive or negative. Therefore, according to the positive and negative points of the engine speed, the shifting process is divided into the following four situations: power upshift, Unpowered upshift, powered downshift, unpowered downshift.

During the power upshift process, the vehicle is in an accelerating state, and the accelerator opening is not 0. Taking the first gear up to the second gear as an example, the pressure of the working cylinder of clutch c1 drops, and the working cylinder of clutch c2 starts to fill with oil. During the upshifting process, the hydraulic pressure changes. The torquer lock-up clutch is unlocked, absorbing the shock of dual clutch switching during gear shifting. The transmission ratio is reduced, and the engine speed is also appropriately reduced, so that the engine speed is consistent with the target speed of the transmission. As the torque transmitted by the clutch c2 increases, the engine torque is appropriately reduced to reduce the slippage of the clutch friction plates, shorten the shift time, and improve the shift quality.

In the process of no power upshift, the vehicle coasts to accelerate the upshift, and the accelerator opening is the smallest. Taking the fifth gear to the sixth gear as an example, the pressure of the clutch c1 working cylinder drops, the clutch c2 working cylinder starts to fill with oil, and the torque of the engine is the resistance torque. As it rises, the torque transmitted by the clutch c2 becomes larger, and the engine torque increases.

During the power downshift process, the accelerator opening is large, and the vehicle is in a state of acceleration and torque increase. Taking the second gear down to the first gear as an example, the pressure of the working cylinder of clutch c2 drops, and the working cylinder of clutch c1 starts to fill with oil, which is the same as the situation of no-power upshift. At this time, the engine torque is still the resistance torque, the transmission ratio increases, and the engine speed is increased. Reduce engine load.

In the process of no power downshift, the accelerator opening is the smallest, and the vehicle decelerates and coasts downshift. At this time, the clutch acts on the vehicle with a resisting torque, and the transmission ratio becomes larger, that is, the speed of the active plate of the coupling clutch in the target gear is higher than that of the active plate of the disengaging clutch in the current gear. The clutch speed difference of the target gear reduces the shift shock.

The hydraulic torque converter is composed of a pump wheel and a turbine. It uses the interaction between the blades of the pump wheel and the turbine and the hydraulic transmission oil to realize the mutual conversion of mechanical energy and liquid energy, so as to achieve the purpose of changing the transmission torque. The torque converter enables continuous changes in speed and torque and absorbs shocks during driving and shifting. The cooperation of the torque converter and the dual-clutch transmission can make the shifting process smoother and the driving more comfortable; at the same time, the fluid coupling transmission has the advantages of smooth shifting, simple operation, high transmission efficiency, good fuel economy, and driving comfort. Good and other advantages.

The control system and control strategy of the hydraulic coupling transmission of the present invention can realize real-time communication between the engine and the transmission, ensure that the engine input speed, torque and transmission gear can meet the needs of the vehicle operation, and at the same time, it can also actively adjust according to the driver's wishes. The operation state of the transmission is ensured, and the automatic transmission can work according to the predetermined optimal control law under any working conditions, so as to achieve the optimal shifting quality and transmission efficiency.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (4)

1. A control system suitable for a hydraulically coupled transmission, characterized in that: comprising an automatic transmission electronic control system and an automatic transmission hydraulic system; The automatic transmission hydraulic system includes an oil pump, an oil supply system, a shifting system, and a torque converter locking and cooling management system. The inlet of the oil supply system is connected to the oil pump, and the outlet of the oil supply system is respectively connected to the shifting system and the cooling system. The torque converter locking and cooling management system, the input end of the shift system is also connected with a shift lever, and the output end of the shift system is connected to the transmission synchronizer through the shift actuator; The automatic transmission electronic control system includes a sensor, a TCU and a solenoid valve, wherein the sensor includes a vehicle speed sensor and an accelerator opening sensor, both of which are connected to the input end of the TCU, and the solenoid valve includes a main oil circuit solenoid valve. , shift solenoid valve and lock control solenoid valve, input ends of main oil circuit solenoid valve, shift solenoid valve and lock control solenoid valve are all connected to the output end of TCU, main oil circuit solenoid valve, shift solenoid valve The output ends of the valve and the lock-up control solenoid valve are respectively connected to the control ends of the oil supply system, the gear shift system and the torque converter lock-up and cooling management system. 2 . The control system according to claim 1 , wherein a torque converter cooling system is connected to the output end of the torque converter lock-up and cooling management system. 3 . device. 3 . The control system of claim 2 , wherein the torque converter lock-up and cooling management system comprises a torque converter lock-up clutch, a turbine speed sensor , pump wheel speed sensor, oil pressure sensor and hydraulic oil temperature sensor, the lock-up clutch, turbine speed sensor, pump wheel speed sensor, oil pressure sensor and hydraulic oil temperature sensor are all connected to the input end of the TCU, torque converter The lock-up clutch is connected to the output end of the TCU, and the TCU can actively control the state of the torque converter lock-up clutch to achieve optimal fuel economy by analyzing and processing the current vehicle driving state and various parameters of the torque converter. 4. A control method suitable for a control system of a hydraulically coupled transmission according to any one of claims 1-3, characterized in that, comprising the following steps: S1. Determine the current state of the torque converter; S2. If it is in a locked state, determine whether it is in a braking state, if it is in a braking state, execute unlocking; if it is in an unlocked state, execute step S3; S3. Determine the current gear, if the gear is neutral or shifting, maintain the current state; S4. If it is in the gear position, judge the hydraulic oil temperature T; S5. If T < 60°C, maintain the current state; if T > 60°C, the TCU judges the current rotational speed of the turbine and pump wheel through the torque converter lockup and cooling management system; S6. If the current rotational speed nw>the preset rotational speed nb, maintain the current state, and if nw<nb, execute the locking operation.

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