Electric drive roller and travel control method and system thereof

Abstract

The present invention relates to an electric-driven roller, and in order to solve the problem that the existing electric-driven roller needs to be equipped with a brake resistor in order to achieve full-power downhill driving, an electric-driven roller and a driving control method and system thereof are provided, wherein the control method steps are to send a speed control instruction to a motor controller according to the swing angle of a travel control handle, detect the machine inclination angle and obtain the power storage capacity of a power battery, and determine whether the machine is in downhill driving according to the machine inclination angle and the swing direction of the handle; when the power storage capacity is greater than a predetermined value, the whole machine controller sends a torque limit instruction with a reverse torque limit value of zero to the motor controller, and when the machine is in downhill driving, the whole machine controller outputs a driving brake current for braking to the driving brake system. The present invention solves the problem of a roller driving downhill with full power without setting a brake resistor, simplifies the structure, and reduces costs.

Description

Technical Field

[0001] The present invention relates to an electric-driven roller, and more particularly to an electric-driven roller and a travel control method and system thereof. Background Art

[0002] The electric roller is an important equipment in construction machinery. The transmission system of the electric roller includes a travel motor, a gearbox and a drive axle that are connected in sequence. The travel motor is usually a permanent magnet motor. When the roller is decelerating, going downhill or braking, the inertia of the machine can be used to reversely drag the travel motor through the transmission system to generate electricity, thereby recovering energy while decelerating the machine. However, when the power battery of the roller is fully charged, the electric energy generated by the reverse braking of the travel motor cannot be recovered. Therefore, it is necessary to set a brake resistor on the roller so that when the power battery is fully charged, the energy generated by the reverse braking of the travel motor can be consumed by heating the brake resistor. Setting up a brake resistor requires additional costs.

[0003] In some electric-driven rollers, the power battery is not fully charged, and the power of the power battery is limited to a certain value so that the energy generated by the reverse braking of the travel motor can be recovered. This solution limits the power battery's capabilities, and during the charging process, it is necessary to prevent the charging power from exceeding the limit in real time, which has certain limitations. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the existing electric-driven roller needs to be equipped with a braking resistor in order to achieve downhill driving with full power. An electric-driven roller and its driving control method and system are provided to solve the downhill braking problem of the electric-driven roller without setting a braking resistor.

[0005] The technical solution of the present invention to achieve its purpose is as follows: a travel control method for an electric drive roller is provided, wherein the travel drive system of the roller comprises a gearbox, a gearbox and a drive axle which are sequentially connected in transmission, and the control method is characterized in that the control method comprises the following steps:

[0006] The whole machine controller sends a speed control command to the motor controller according to the swing angle of the travel control handle, detects the machine inclination angle in the front and rear directions of the roller and obtains the storage capacity of the power battery, and determines whether the machine is traveling downhill according to the machine inclination angle and the swing angle of the handle; when the storage capacity is greater than a predetermined percentage, it is determined to be in a fully charged state, otherwise it is in a partially charged state;

[0007] In the fully charged state, the whole machine controller sends a zero-value anti-drag torque limit instruction to the motor controller, and when the machine is in downhill driving, the whole machine controller outputs a predetermined service brake current to the service brake system.

[0008] In the present invention, when the road roller is fully charged and traveling downhill, braking is performed by the service brake system instead of using the travel motor to reversely drag and decelerate, thereby achieving full-charge downhill travel without setting a brake resistor.

[0009] In the above-mentioned driving control method of the electric-driven roller, when the roller is fully charged and driving downhill, the service brake current output by the whole machine controller to the service brake system is positively correlated with the machine inclination angle. The larger the service brake current, the greater the braking resistance generated by the service brake system. When the front and rear inclination angles of the roller are larger, that is, the steeper the slope, the greater the service brake current output by the whole machine controller.

[0010] In the above-mentioned electric-driven roller driving control method, a torque reference value corresponding to the handle swing angle is pre-set. When the machine is fully charged and driving downhill, if the current torque of the travel motor is greater than the torque reference value corresponding to the current handle swing angle, the service brake current is reduced at a predetermined slope until the torque of the travel motor is equal to the torque reference value corresponding to the current handle swing angle. The torque reference value can refer to the condition of the roller driving on flat ground. When driving on flat ground, when the travel control handle is swung to a certain angle and the driving speed reaches the speed corresponding to the handle swing angle, the output torque of the travel motor is used as the torque reference value of the travel control handle at the swing angle. When the roller is driving downhill, if the output torque of the travel motor is greater than the corresponding torque reference value, it means that the braking torque of the service brake system is too large at this time. The service brake current can be reduced to reduce the braking torque, thereby reducing the load on the travel motor.

[0011] In the above-mentioned electric drive roller driving control method, when the machine is fully charged and driving downhill, if the current speed of the travel motor is greater than the speed corresponding to the current handle swing angle, the service brake current is increased at a predetermined slope until the travel motor speed is equal to the speed corresponding to the current handle swing angle. When the machine's driving speed is greater than the speed corresponding to the current handle swing angle, it means that the braking torque of the service brake system is too small at this time, and the service brake current is increased to increase the braking torque and reduce the machine speed.

[0012] In the above-mentioned electric drive roller travel control method, when the machine is in full power state and the travel control handle returns to the middle position, the whole machine controller outputs the maximum service brake current and activates the parking brake when the travel motor speed is zero and stops outputting the service brake current after a predetermined time after the parking brake is activated.

[0013] In the above-mentioned electric drive road roller travel control method, when the power is not fully charged, the whole machine controller sends a torque limit instruction of the maximum torque value to the motor controller without limiting the reverse torque.

[0014] The technical solution for achieving the purpose of the present invention is as follows: Provide an electric drive roller travel control system, which includes a whole machine controller, a service brake system, a travel drive system, and a travel control handle, wherein the travel drive system includes a gearbox connected between a travel motor and a drive axle, and a motor controller for controlling the travel motor, characterized in that the travel control system also includes an inclination sensor for detecting the inclination of the roller in the front and rear directions, and does not have a brake resistor connected to the motor controller;

[0015] The whole machine controller sends a speed control instruction to the motor controller according to the handle swing angle of the travel control handle, and determines whether the machine is traveling downhill according to the machine inclination angle and the handle swing angle. When the power battery is fully charged, it sends a zero-value anti-drag torque limit instruction to the motor controller, and outputs a service brake current corresponding to the machine inclination angle to the service brake system when traveling downhill.

[0016] In the above-mentioned electric-driven roller driving control system, the driving control system also includes a parking brake system. The whole machine controller outputs the maximum service brake current when it is fully charged and the travel control handle returns to the middle position, and starts the parking brake system to perform parking braking when the travel motor speed is zero, and stops outputting the service brake current after a predetermined time after the parking brake is started.

[0017] In the above-mentioned electric drive roller driving control system, the whole machine controller also includes a storage unit for storing a torque reference value corresponding to the handle swing angle. When the roller is fully charged and driving downhill and the current torque of the travel motor is greater than the torque reference value corresponding to the current handle swing angle, the whole machine controller reduces the service braking current at a predetermined slope until the torque of the travel motor is equal to the torque reference value corresponding to the current handle swing angle.

[0018] The technical solution of the present invention to achieve its purpose is as follows: an electric-driven roller is provided, characterized in that the roller has the above-mentioned electric-driven roller travel control system.

[0019] Compared with the prior art, the present invention solves the problem of the roller running downhill with full power without setting a braking resistor, thereby simplifying the structure and reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a block diagram of the travel control system of the electric-driven roller of the present invention.

[0021] Parts names and serial numbers in the figure:

[0022] Service brake system 1, tilt sensor 2, travel control handle 3, vehicle controller 4, parking brake system 5, motor controller 6, travel motor 7, gearbox 8, drive axle 9. DETAILED DESCRIPTION

[0023] The specific implementation scheme is described below with reference to the accompanying drawings.

[0024] like Figure 1 As shown, the travel control system of the electric-driven roller in this embodiment includes a whole machine controller 4, a travel motor 7, a travel control handle 3, a motor controller 6, a service brake system 1, a parking brake system 5, etc.

[0025] The travel control handle 3 is connected to the whole machine controller 4 through the CAN bus and is used to control the roller. The travel control handle 3 controls the roller's travel and parking brake by swinging forward and backward and returning to the center position. When the travel control handle 3 swings forward relative to the machine, the travel motor 7 rotates forward and the machine moves forward; when the travel control handle 3 swings backward, the travel motor 7 rotates reversely. When the travel control handle 3 returns to the center position, the service brake system 1 performs the service brake operation. When the speed of the travel motor is zero, the parking brake system 5 performs the parking brake operation. The swing angle of the travel control handle 3 corresponds linearly to the target speed of the travel motor 7.

[0026] The inclination sensor 2 is connected to the vehicle controller 4 via a CAN bus or an analog signal line, and is used to detect the inclination angle of the roller, that is, the road slope.

[0027] The motor controller 6 is connected to the whole machine controller 4 and the travel motor 7 via the CAN bus, and is used to control the rotation direction, speed and torque of the travel motor 7 according to the control instructions of the whole machine controller 4.

[0028] The service brake system 1 is connected to the whole machine controller 4, and is used to perform service braking or release service braking according to the control instructions of the whole machine controller 4. The whole machine controller 4 outputs a service brake current to control the service brake proportional valve in the service brake system 1. The larger the service brake current, the larger the valve opening of the service brake proportional valve, and the greater the braking torque generated by the service brake system 1.

[0029] The parking brake system 5 is connected to the whole machine controller 4 and is used for performing parking brake or releasing parking brake according to the control instruction of the whole machine controller 4 .

[0030] The whole machine controller 4 obtains the working load information of the travel motor 7, including the travel motor speed, the travel motor output torque and the like.

[0031] The whole machine controller 4 includes a storage unit and a control unit.

[0032] The storage unit is used to store the driving brake current corresponding to the minimum braking force required for different slopes and the torque reference value corresponding to different handle swing angles. The torque reference value is based on the driving environment of flat ground. When the travel control handle is swung to a certain angle, the machine reaches the set speed corresponding to the handle swing angle.

[0033] The control unit is used to control the operation of the travel motor 7 according to the state change of the travel control handle 3 according to the predetermined control strategy, and control the operation of the service brake system 1 and the parking brake system 5. The travel motor 7 is a permanent magnet synchronous motor, which is connected to the gearbox 8, and the gearbox 8 is connected to the drive axle 9, and the drive axle 9 drives the rear wheels of the roller to rotate.

[0034] In the present invention, the road roller is not provided with a braking resistor, and brakes and decelerates when the power battery is fully charged, without relying on the reverse-dragging travel motor to absorb the kinetic energy of the machine.

[0035] The control method of the electric drive roller travel control system in this embodiment is as follows:

[0036] When the travel control handle is not in the middle position, the whole machine controller sends a corresponding speed command to the motor controller according to the swing angle of the handle, and releases the parking brake of the parking brake system.

[0037] The whole machine controller obtains the storage capacity of the machine's power battery, and if its storage capacity is greater than a predetermined percentage, it is considered to be fully charged. A power battery in a fully charged state cannot absorb the electrical energy generated by the travel motor when it is reversely dragged.

[0038] The whole machine controller detects the machine inclination angle in the front and rear direction of the roller through the inclination sensor, and judges whether the roller is in a downhill driving state in combination with the swing direction of the handle. The inclination sensor angle is defined as positive when the front of the vehicle (the front of the roller) is tilted up, and negative when the front of the vehicle is tilted down. When the driving control handle is pushed forward and the inclination sensor angle is detected to be negative, the whole vehicle is judged to be in a forward downhill state. When the driving control handle is pulled back and the inclination sensor angle is detected to be positive, the whole vehicle is judged to be in a backward downhill state.

[0039] When the vehicle controller determines that the machine is in a downhill state and the power battery is fully charged, the machine controller sends a speed control command to the motor controller according to the handle swing angle of the travel control handle, and at the same time sends a torque limit command with a reverse torque limit of zero to the motor controller, and outputs a service brake current for braking to the service brake system according to the machine inclination angle.

[0040] The reverse-tow torque limit is zero. When the roller goes downhill, the machine reverse-tows the travel motor through the drive axle and gearbox, and the generator does not absorb the kinetic energy of the machine to generate electricity. The service brake current output by the vehicle controller opens the service brake proportional valve of the service brake system to the corresponding opening, generating the corresponding braking torque. The motor controller controls the travel motor to rotate according to the speed control command of the whole machine, so that it moves at the target speed.

[0041] When the machine is fully charged and traveling downhill, if the current speed of the travel motor is greater than the speed corresponding to the current handle swing angle, the whole machine controller increases the service brake current used for braking at a predetermined slope based on the current service brake current to increase the braking torque and reduce the speed of the roller until the travel motor speed is equal to the speed corresponding to the current handle swing angle.

[0042] When the machine is fully charged and traveling downhill, if the current torque of the travel motor is greater than the torque reference value corresponding to the current handle swing angle, the whole machine controller reduces the service brake current used for braking at a predetermined slope based on the current service brake current until the torque of the travel motor is equal to the torque reference value corresponding to the current handle swing angle.

[0043] When the machine is fully powered and the travel control handle returns to the middle position, the machine controller outputs the maximum service brake current and activates the parking brake system to perform parking brake when the travel motor speed is zero, and stops outputting the service brake current after a predetermined time after the parking brake is activated.

[0044] When the power storage capacity of the power battery is less than the set value, the whole machine controller does not limit the reverse torque of the travel motor. When the roller is decelerating or going down a steep slope, the machine reverses the travel motor through the travel drive system. The travel motor absorbs the kinetic energy of the machine and converts it into electrical energy and stores it in the power battery.

Claims

1. A travel control method for an electric-driven roller, wherein the travel drive system of the roller comprises a gearbox connected between a travel motor and a drive axle and a motor controller for controlling the travel motor, characterized in that The roller does not have a braking resistor, and the control method steps are as follows: The whole machine controller sends a speed control command to the motor controller according to the swing angle of the travel control handle, detects the machine inclination angle in the front and rear directions of the roller and obtains the storage capacity of the power battery, and determines whether the machine is traveling downhill according to the machine inclination angle and the swing direction of the handle; when the storage capacity is greater than a predetermined percentage, it is determined to be in a fully charged state, otherwise it is in a partially charged state; the motor controller controls the travel motor to operate in a speed mode; In the fully charged state, the whole machine controller sends a zero-value anti-drag torque limit instruction to the motor controller, and when the machine is traveling downhill, the whole machine controller outputs a predetermined service braking current to the service braking system; a torque reference value corresponding to the handle swing angle is pre-set, and when the machine is fully charged and traveling downhill, if the current torque of the travel motor is greater than the torque reference value corresponding to the current handle swing angle, the service braking current is reduced at a predetermined slope until the torque of the travel motor is equal to the torque reference value corresponding to the current handle swing angle.

2. The driving control method of an electric driven road roller according to claim 1, characterized in that When the machine is fully charged and driving downhill, the service brake current output by the whole machine controller to the service brake system is positively correlated with the machine inclination angle.

3. The driving control method of an electric driven roller according to claim 2, characterized in that When the machine is fully charged and traveling downhill, if the current speed of the travel motor is greater than the speed corresponding to the current handle swing angle, the service brake current is increased at a predetermined slope until the travel motor speed is equal to the speed corresponding to the current handle swing angle.

4. The driving control method of an electric-driven road roller according to any one of claims 1 to 3, characterized in that When the vehicle is fully charged and the travel control handle returns to the middle position, the whole machine controller outputs the maximum service brake current and activates the parking brake when the travel motor speed is zero, and stops outputting the service brake current after a predetermined time after the parking brake is activated.

5. The driving control method of an electric driven road roller according to claim 1, characterized in that When the power is not fully charged, the whole machine controller sends a torque limit command of the maximum torque value to the motor controller without limiting the reverse torque.

6. An electric drive roller travel control system, which includes a whole machine controller, a service brake system, a travel drive system, and a travel control handle. The travel drive system includes a gearbox connected between the travel motor and the drive axle and a motor controller for controlling the travel motor, characterized in that The travel control system also includes an inclination sensor for detecting the inclination of the roller in the front-rear direction, and a brake resistor not connected to the motor controller; The whole machine controller sends a speed control instruction to the motor controller according to the handle swing angle of the travel control handle, and determines whether the machine is traveling downhill according to the machine inclination angle and the handle swing direction, sends a zero-value anti-drag torque limit instruction to the motor controller when the power battery is fully charged, and outputs a service braking current corresponding to the machine inclination angle to the service braking system when traveling downhill; the whole machine controller includes a storage unit for storing a torque reference value corresponding to the handle swing angle. When the roller is traveling uphill in a fully charged state and the current torque of the travel motor is greater than the torque reference value corresponding to the current handle swing angle, the whole machine controller reduces the service braking current at a predetermined slope until the torque of the travel motor is equal to the torque reference value corresponding to the current handle swing angle.

7. The electric drive roller travel control system according to claim 6, characterized in that The driving control system also includes a parking brake system. The whole machine controller outputs the maximum service brake current when it is fully charged and the travel control handle returns to the middle position, and activates the parking brake system to perform parking braking when the travel motor speed is zero, and stops outputting the service brake current after a predetermined time after the parking brake is activated.

8. An electric driven roller, characterized in that This road roller has the travel control system according to any one of claims 6 to 7.

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