An electric excavator battery swapping system and its control method

Abstract

The present invention provides an electric excavator battery swapping system and its control method. The electric excavator battery swapping system includes a one-key battery swapping switch, a position sensor, an electric control lock, a connection detector, and a leveling device. The one-key battery swapping switch, the position sensor, the electric control lock, and the leveling device are respectively connected to the vehicle controller VCU, and the vehicle controller VCU is connected to the battery box through the connection detector. Based on the electric excavator battery swapping control method of the electric excavator battery swapping system, before battery swapping, the high-voltage state monitoring and the electric control lock state monitoring of the electric excavator are completed. During the battery swapping process, the leveling device is used to level the falling new battery box to avoid the battery box being tilted and stuck. After battery swapping, the connection detector is used to detect the connection signal and the displacement sensor is used to confirm, so as to ensure the accuracy of the falling position of the battery box. The present invention reduces the requirements of the electric excavator for the battery swapping environment, realizes the on-site replacement of the battery box of the electric excavator at any time under multiple working conditions, and improves the convenience and accuracy of the battery swapping operation.

Description

Technical Field

[0001] An electric excavator battery swapping system and its control method relate to the field of construction machinery, especially the field of pure electric construction machinery. Background Art

[0002] Based on the promotion of the dual-carbon policy and the international situation of rising oil prices, pure electric excavators are gradually moving onto the main stage of the market. Compared with traditional diesel excavators, electric excavators have the advantages of energy conservation and environmental protection, which conform to the market development trend. However, the drawback of poor endurance of electric excavators has led to user dissatisfaction with pure electric excavators.

[0003] Battery swapping is an energy design method that separates the vehicle from the power battery. By replacing the power battery, it optimizes and replaces the long charging time, extending the endurance time of the electric excavator.

[0004] In the prior art, for an electric excavator to swap batteries, the electric excavator needs to be parked around a battery swapping station or a battery swapping vehicle. After reaching the designated position that meets the battery swapping conditions, the driver first needs to manually power off, and then can turn on the battery swapping switch. After the in-vehicle VCU receives the battery swapping signal, it sends an instruction to the battery swapping controller. After the battery swapping controller judges the state of the battery swapping base, it sends the battery swapping instruction to the battery swapping base cylinder controller. The battery swapping base cylinder controller controls the cylinder to perform the unlocking operation of the battery swapping base. After the battery swapping is completed, the battery swapping switch is closed. After receiving the instruction, the VCU sends a control instruction to the battery swapping controller to perform the locking operation of the battery swapping base cylinder.

[0005] Currently, the battery swapping of electric excavators has too high requirements for the battery swapping environment, the battery swapping logic is cumbersome, the control process has many steps, and a leveling device is not used during the battery swapping process. It is easy for the electric box to be unable to drop due to the inclination of the electric box angle, and in severe cases, it may even damage the electric box and other devices. Summary of the Invention

[0006] The purpose of the present invention is to reduce the requirements of electric excavators for the battery swapping environment, realize the on-site replacement of the electric box of electric excavators at any time under multiple working conditions, and improve the convenience of battery swapping operations.

[0007] To achieve the above object, the present invention provides the following technical solution: An electric excavator battery swapping system, including a one-key battery swapping switch, a position sensor, an electric control lock, a connection detector, and a leveling device; the one-key battery swapping switch is connected to the vehicle control unit VCU, and is used to trigger the battery swapping operation of the electric excavator with one key; the electric control lock is used to fix the battery box on the electric excavator, and the electric control lock is connected to the vehicle control unit VCU; the electric control lock realizes the switching between two states of locking and unlocking under the control instruction of the vehicle control unit VCU; the position sensor is connected to the vehicle control unit VCU; it is used to monitor the position of the battery box; the vehicle control unit VCU is connected to the battery box through the connection detector; the connection detector repeatedly detects the on-off state with the battery box at a preset frequency under the instruction of the vehicle control unit VCU, and sends a state change signal to the vehicle control unit VCU when the on-off state changes; among them, the state change signal includes a change signal from on to off and a change signal from off to on; the leveling device includes a power source and at least 2 oil cylinders with telescopic columns; the power source is used to provide power for each oil cylinder; each oil cylinder is respectively provided with a pressure sensor, and the power source and each pressure sensor are respectively connected to the vehicle control unit VCU; the vehicle control unit VCU obtains the balance state of the falling battery box according to the pressure difference information between the pressure sensors, and then makes corresponding leveling operations on each telescopic column by controlling the output of the power source; the extension ends of each telescopic column are in relatively stable contact with the preset area at the bottom of the battery box through a mutually matching structure. During the falling process of the battery box, the vehicle control unit VCU controls each telescopic column to position the battery box above the specified position and level it in real time until the battery box falls to the specified position.

[0008] Further, the aforementioned one-key battery swapping switch adopts the form of a button, and the button is arranged in the instrument interface of the electric excavator.

[0009] Further, a battery swapping control method based on the aforementioned electric excavator battery swapping system, triggered by the one-key battery swapping switch to issue a battery swapping instruction, the battery swapping control includes the following steps:

[0010] Step 1: The vehicle control unit VCU judges the current voltage state of the electric excavator; if the electric excavator is in a low-voltage state, it enters Step 2; if the electric excavator is in a high-voltage state, the vehicle control unit VCU first controls to cut off the high-voltage power supply, and then enters Step 2;

[0011] Step 2: The vehicle control unit VCU judges the state of the electric control lock; if the electric control lock is in the locked state, it enters Step 3; if the electric control lock is in the unlocked state, it enters Step 4;

[0012] Step 3: The vehicle control unit VCU controls the electric control lock to perform an unlocking operation, updates the state of the electric control lock to unlocked, and then enters Step 4;

[0013] Step 4: Take out the electrical box, disconnect the connection between the detector and the electrical box, and connect the detector to send a change signal from on to off to the vehicle control unit (VCU). After receiving the change signal, the VCU tracks the real-time position of the electrical box through the position sensor. When the electrical box is completely taken out, the VCU starts the leveling device and controls each telescopic column to extend by a preset length L1; then proceed to Step 5;

[0014] Step 5: Based on the new electrical box to be replaced falling to the height where the extended ends of the telescopic columns are located, the extended ends of the telescopic columns are in relatively stable contact with the preset area at the bottom of the new electrical box to be replaced. Each pressure sensor obtains pressure data. The VCU controls the output of the power source to level the falling new electrical box according to the pressure difference information between the pressure sensors; when the position sensor detects that the new electrical box has fallen to the preset height H1, proceed to Step 6;

[0015] Step 6: The VCU controls the connection detector to repeatedly detect the on signal at a preset frequency and tracks the real-time position of the new electrical box through the position sensor; if the position sensor detects that the new electrical box has been placed at the specified position and the VCU receives a change signal from off to on, then proceed to Step 7; if the position sensor detects that the new electrical box has been placed at the specified position but the VCU does not receive a change signal from off to on, then the VCU issues an error warning and then proceeds to Step 4 to re-place the new electrical box;

[0016] Step 7: The VCU controls the leveling device to release pressure and retract each telescopic column; after a preset time delay, the VCU controls the electric lock to perform a locking operation and updates the status of the electric lock to locked.

[0017] Further, the operation of the VCU to level the electrical box is specifically as follows: If the pressure difference between the pressure sensors reaches the upper limit of the preset range, it indicates that the electrical box is tilted. The VCU will control the power source to increase the output to the oil cylinder with a larger pressure value until the pressure difference between the pressure sensors is within the preset range. The VCU will balance the output of each oil cylinder to maintain the stable descent of the new electrical box.

[0018] For the electric excavator battery swapping system and its control method of the present invention, compared with the prior art by adopting the above technical solutions, it has the following technical effects:

[0019] 1. The present invention can realize on-site battery swapping of electric excavators at any time under multiple working conditions, greatly reducing the battery swapping time and improving the convenience of battery swapping operations;

[0020] 2. The present invention optimizes the control strategy by integrating the control unit into the vehicle controller VCU, triggering the battery swapping procedure with one key, and improving the working efficiency of the electric excavator. At the same time, the present invention ensures that the electric box is firmly placed in the designated position by connecting the detector, position sensor, and electric control lock, avoiding poor power supply contact during the operation of the electric excavator or after battery swapping.

[0021] 3. The present invention adds a leveling device during the battery swapping process to ensure that the electric box is placed smoothly in the designated position, preventing damage to the equipment due to the inclination of the electric box. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a block diagram of the battery swapping system of the electric excavator in the embodiment of the present invention;

[0023] Figure 2 is a flowchart of the battery swapping of the electric excavator in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] In order to better understand the technical content of the present invention, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.

[0025] In the present invention, various aspects of the present invention are described with reference to the drawings, and many illustrative embodiments are shown in the drawings. The embodiments of the present invention are not limited to those described in the drawings. It should be understood that the present invention can be implemented by any of the various concepts and embodiments introduced above, as well as the concepts and embodiments described in detail below, because the concepts and embodiments disclosed in the present invention are not limited to any embodiment. In addition, some aspects disclosed in the present invention can be used alone, or in any suitable combination with other aspects disclosed in the present invention.

[0026] In this embodiment, an electric excavator battery swapping system, as Figure 1 shown, includes a one-key battery swapping switch, a position sensor, an electric control lock, a connection detector, and a leveling device; the one-key battery swapping switch is connected to the vehicle controller VCU; the electric control lock is connected to the vehicle controller VCU; the position sensor is connected to the vehicle controller VCU; the vehicle controller VCU is connected to the electric box through the connection detector; the leveling device includes a power source and 4 cylinders with telescopic columns; the power source is used to provide power for each cylinder; each cylinder is respectively provided with a pressure sensor, and the power source and each pressure sensor are respectively connected to the vehicle controller VCU. The extending ends of the 4 telescopic columns are provided with circular balls, and circular grooves corresponding to the circular balls are opened at the four corners of the bottom of the electric box. The circular balls at the ends of the 4 telescopic columns respectively slide into the corresponding circular grooves, and the 4 telescopic columns and the bottom of the electric box achieve relatively stable contact; during the falling process of the electric box, the vehicle controller VCU controls each telescopic column to position the electric box above the designated position and level it in real time until the electric box falls to the designated position.

[0027] As Figure 2 shown, based on the one-key battery swapping switch to trigger the battery swapping instruction, the battery swapping control includes the following steps:

[0028] Step 1: The vehicle control unit (VCU) of the whole vehicle judges the current voltage state of the electric excavator; if the electric excavator is in a low-voltage state, go to Step 2; if the electric excavator is in a high-voltage state, the VCU of the whole vehicle first controls to cut off the high-voltage power supply, and then goes to Step 2;

[0029] Step 2: The VCU of the whole vehicle judges the state of the electric control lock; if the electric control lock is in the locked state, go to Step 3; if the electric control lock is in the unlocked state, go to Step 4;

[0030] Step 3: The VCU of the whole vehicle controls the electric control lock to perform an unlocking operation, and updates the state of the electric control lock to unlocked, and then goes to Step 4;

[0031] Step 4: After confirming that the electric control lock is in the unlocked state, use the crane to take out the electric box, disconnect the connection between the detector and the electric box, and the connection detector sends a change signal from on to off to the VCU of the whole vehicle. After receiving the change signal, the VCU of the whole vehicle enables the position sensor to track the real-time position of the electric box. When the electric box is lifted out of the electric box slot by the crane, the VCU of the whole vehicle starts the leveling device and controls the 4 telescopic columns to extend 500 mm in length; then go to Step 5;

[0032] Step 5: When the newly replaced electric box drops to the height where the extended ends of the 4 telescopic columns are located, the extended ends of the 4 telescopic columns respectively slide into the circular grooves at the four corners of the bottom of the new electric box. The VCU of the whole vehicle controls the 4 telescopic columns to position the new electric box directly above the electric box slot. At the same time, each pressure sensor obtains pressure data. The VCU of the whole vehicle controls the output of the power source to level the falling electric box according to the pressure difference information between the pressure sensors; if the pressure difference between the pressure sensors reaches the upper limit value of the preset range, it indicates that the electric box is tilted. The VCU of the whole vehicle will control the power source to increase the output of the oil cylinder with a larger pressure value until the pressure difference between the pressure sensors is within the preset range. The VCU of the whole vehicle will balance the output of each oil cylinder to maintain the smooth falling of the new electric box; when the position sensor detects that the new electric box drops to a height of 200 mm, then go to Step 6;

[0033] Step 6: The vehicle control unit (VCU) controls the connection detector to repeatedly detect the on-signal at a frequency of once per second and tracks the real-time position of the electrical box through the position sensor; if the position sensor detects that the new electrical box has fallen into the electrical box slot and the VCU receives a change signal from off to on, proceed to Step 7; if the position sensor detects that the new electrical box has fallen into the electrical box slot but the VCU does not receive a change signal from off to on, the VCU issues an error warning and then proceeds to Step 4 to re-place the new electrical box.

[0034] Step 7: The VCU controls the leveling device to release pressure and retract each telescopic column; after a 5-second delay, the VCU controls the electric lock to perform a locking operation and updates the status of the electric lock to locked.

[0035] Although the present invention has been described above with reference to preferred embodiments, it is not intended to limit the present invention. Those of ordinary skill in the art to which the present invention pertains may make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be defined by the claims.

Claims

1. An electric excavator battery swapping system for realizing the vehicle control unit (VCU) to control the electric excavator to replace the battery box in place, characterized in that, It includes a one - key power - swapping switch, a position sensor, an electric control lock, a connection detector, and a leveling device; The one - key power - swapping switch is connected to the vehicle control unit (VCU) of the whole vehicle and is used to trigger the power - swapping operation of the electric excavator with one key; The electric control lock is used to fix the power box on the electric excavator. The electric control lock is connected to the vehicle control unit (VCU) of the whole vehicle; under the control instruction of the vehicle control unit (VCU) of the whole vehicle, the electric control lock realizes the switching between two states of locking and unlocking; The position sensor is connected to the vehicle control unit (VCU) of the whole vehicle and is used to monitor the position of the power box; The vehicle control unit (VCU) of the whole vehicle is connected to the power box through the connection detector; the connection detector repeatedly detects the on - off state with the power box at a preset frequency under the instruction of the vehicle control unit (VCU) of the whole vehicle, and sends a state - change signal to the vehicle control unit (VCU) of the whole vehicle when the on - off state changes; among them, the state - change signal includes a change signal from on to off and a change signal from off to on; The leveling device includes a power source and at least two oil cylinders with telescopic columns; the power source is used to provide power for each oil cylinder; each oil cylinder is respectively equipped with a pressure sensor, and the power source and each pressure sensor are respectively connected to the vehicle control unit (VCU) of the whole vehicle; the vehicle control unit (VCU) of the whole vehicle obtains the balance state of the falling power box according to the pressure difference information between the pressure sensors, and then makes corresponding leveling operations on each telescopic column by controlling the output of the power source; The extension ends of the telescopic columns are in relatively stable contact with the preset area at the bottom of the power box through a mutually matching structure. During the falling process of the power box, each telescopic column positions the power box above the designated position under the control of the vehicle control unit (VCU) of the whole vehicle and levels it in real - time until the power box falls to the designated position.

2. The electric excavator battery swapping system according to claim 1, characterized in that, The one - key power - swapping switch is in the form of a button, and the button is set in the instrument interface of the electric excavator.

3. A method for controlling the battery swapping of an electric excavator based on the battery swapping system described in claim 1, characterized in that, Based on the triggering of the power - swapping instruction by the one - key power - swapping switch, the power - swapping control includes the following steps: Step 1: The vehicle control unit (VCU) of the whole vehicle judges the current voltage state of the electric excavator; if the electric excavator is in a low - voltage state, then go to Step 2; if the electric excavator is in a high - voltage state, the vehicle control unit (VCU) of the whole vehicle first controls the cutting off of the high - voltage power supply, and then goes to Step 2; Step 2: The vehicle control unit (VCU) of the whole vehicle judges the state of the electric control lock; If the electric control lock is in the locked state, then go to Step 3; If the electric control lock is in the unlocked state, then go to Step 4; Step 3: The vehicle control unit (VCU) of the whole vehicle controls the electric control lock to perform an unlocking operation, updates the state of the electric control lock to unlocked, and then goes to Step 4; Step 4: Take out the power box. The connection between the connection detector and the power box is disconnected, and the connection detector sends a change signal from on to off to the vehicle control unit (VCU) of the whole vehicle. After receiving the change signal, the vehicle control unit (VCU) of the whole vehicle tracks the real - time position of the power box through the position sensor. After the power box is completely taken out, the vehicle control unit (VCU) of the whole vehicle starts the leveling device and controls each telescopic column to extend a preset length L1; then go to Step 5; Step 5: Based on the fact that the replaced new electrical box drops to the height where the extended ends of the telescopic columns are located, the extended ends of the telescopic columns are in relatively stable contact with the preset area at the bottom of the replaced new electrical box. Each pressure sensor obtains pressure data. The vehicle control unit (VCU) controls the output of the power source according to the pressure difference information between the pressure sensors to level the dropping electrical box. When the position sensor detects that the new electrical box drops to the preset height H1, proceed to Step 6; Step 6: The vehicle control unit (VCU) controls the connection detector to repeatedly detect the connection signal at a preset frequency and tracks the real-time position of the new electrical box through the position sensor. If the position sensor detects that the new electrical box is placed at the specified position and the vehicle control unit (VCU) receives a change signal from off to on, proceed to Step 7; if the position sensor detects that the new electrical box is placed at the specified position but the vehicle control unit (VCU) does not receive a change signal from off to on, the vehicle control unit (VCU) issues an error warning and then proceeds to Step 4 to re-place the new electrical box; Step 7: The vehicle control unit (VCU) controls the leveling device to release pressure and retract each telescopic column; After a preset time delay, the vehicle control unit (VCU) controls the electric lock to perform a locking operation and updates the status of the electric lock to locked.

4. The electric excavator battery swapping control method according to claim 3, wherein The specific operation of the vehicle control unit (VCU) to level the electrical box is as follows: If the pressure difference between the pressure sensors reaches the upper limit of the preset range, it indicates that the electrical box is tilted. The vehicle control unit (VCU) will control the power source to increase the output to the cylinder with a larger pressure value until the pressure difference between the pressure sensors is within the preset range. The vehicle control unit (VCU) will balance the output of each cylinder to maintain the stable dropping of the electrical box.

Images