Split type battery system of electric excavator and control method

Abstract

The invention discloses an electric excavator split type battery system and a control method, the electric excavator split type battery system comprises a charge and discharge control loop and at least two distributed electric boxes, the charge and discharge control loop and each distributed electric box are connected in series on a discharge main loop; the charging and discharging control loop is used for controlling a circulation path of charging and discharging current of each distributed electric box; the box body series relay is connected in series between two adjacent distributed electric boxes; and the main control unit is used for receiving an external control signal and controlling the relay connected in series with the box body and the relay in the charging and discharging control loop. According to the invention, it is ensured that the distributed electric box is completely disconnected from the main discharge loop in the power-off process, so that the risk of electric shock is avoided, and the safety of the circuit is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of excavators, and in particular to a split battery system and a control method for an electric excavator. Background Art

[0002] At present, the electric boxes equipped with electric excavators in the construction machinery industry are mainly divided into two types: integrated electric boxes and distributed electric boxes. Among them, the distributed electric box generally does not include a disconnection module, and the box power supply is mainly cut off through the box manual service disconnect (MSD).

[0003] However, when using MSD to cut off the power supply of the box, there are the following safety hazards. First: If the main circuit relay in the high-voltage box of the vehicle is cut off, the operator must wait until the high-voltage box is completely powered off before unplugging the manual maintenance switch (MSD). If the main positive and negative relays are stuck, resulting in the MSD being unplugged when the power is not completely off, there will be a risk of live operation, which may cause serious harm to the operator. Second: After the main circuit relay is cut off, if the MSD is not unplugged in advance, the operator cannot operate the positive and negative poles of the electrical box. At this time, the positive and negative poles may still be energized. If the operator disassembles these connections, he will face the risk of electric shock. Summary of the invention

[0004] The present invention provides a split battery system and a control method for an electric excavator, so as to improve the safety when the MSD is used to cut off the power supply of the excavator case.

[0005] According to one aspect of the present invention, there is provided a split battery system for an electric excavator, comprising:

[0006] A charge and discharge control circuit and at least two distributed electric boxes, wherein the charge and discharge control circuit and each of the distributed electric boxes are connected in series to a main discharge circuit; the charge and discharge control circuit is used to control the flow path of the charge and discharge current of each of the distributed electric boxes;

[0007] A box series relay is connected in series between two adjacent distributed electric boxes;

[0008] A main control unit is used to receive an external control signal and control the box series relay and the relay in the charge and discharge control circuit.

[0009] Optionally, the split battery system for electric excavator further includes: an upper box, an upper box slave control, at least one lower box and at least one lower box slave control;

[0010] Among them, the main control unit, the upper box slave control and the charge and discharge control circuit are arranged in the upper box; the lower box slave control and the box series relay are arranged in the lower box.

[0011] Optionally, the electric excavator split battery system further includes: at least two manual maintenance switches connected in series to the main discharge circuit, and each of the manual maintenance switches is respectively arranged in the upper box body and the lower box body.

[0012] Optionally, the charge and discharge control circuit includes: a main positive relay, a main negative relay, a fuse and a current sensor connected in series to the main discharge circuit; wherein the main positive relay and the main negative relay are controlled by the main control unit, and the current sensor is used to send current collection information to the main control unit;

[0013] Among them, one end of the main positive relay is coupled to the discharge positive interface, and one end of the main negative relay is coupled to the discharge negative interface.

[0014] Optionally, the split battery system for electric excavator further includes at least one of the following circuits:

[0015] A pre-charging circuit, comprising a pre-charging relay and a pre-charging resistor, wherein the pre-charging relay and the pre-charging resistor are connected in series and then connected in parallel with the main positive relay;

[0016] A charging circuit, comprising a charging relay, one end of which is coupled to the charging positive interface, and the other end of which is coupled to the other end of the main positive relay; one end of the main negative relay is also coupled to the charging negative interface;

[0017] The heating circuit comprises a heating relay, the discharge positive interface and the charging positive interface are both coupled to one end of the heating relay, and the other end of the heating relay is coupled to the heating module.

[0018] According to another aspect of the present invention, a control method for a split battery system for an electric excavator is provided, which can be implemented by using the split battery system for an electric excavator provided by any embodiment of the present invention; the control method comprises:

[0019] The relay in the charge and discharge control loop and the box series relay are controlled to be closed and cut off according to the preset control logic.

[0020] The technical solution provided by the embodiment of the present invention controls the switching state of the box series relay through the main control unit to realize the on and off of the main discharge circuit of the battery system, which can ensure that during the power-off process, the distributed power box is completely disconnected from the main discharge circuit, thereby avoiding the risk of electric shock and improving the safety of the circuit.

[0021] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A schematic diagram of a split battery system for an electric excavator provided by an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of another split battery system for an electric excavator provided by an embodiment of the present invention;

[0025] Figure 3 A schematic diagram of another split battery system for an electric excavator provided by an embodiment of the present invention;

[0026] Figure 4 A flow chart of another control method of a split battery system for an electric excavator provided by an embodiment of the present invention;

[0027] Figure 5 A flow chart of another control method of a split battery system for an electric excavator provided by an embodiment of the present invention;

[0028] Figure 6 A flowchart of another control method of a split battery system for an electric excavator provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] Figure 1 The schematic diagram of a split battery system for an electric excavator provided by an embodiment of the present invention is applicable to the case where the power supply of the excavator body is cut off. The split battery system for an electric excavator can be configured in the excavator. Figure 1 As shown, the system includes:

[0032] The charge and discharge control circuit 110 and at least two distributed electric boxes 120 are connected in series to the main discharge circuit; the charge and discharge control circuit 110 is used to control the flow path of the charge and discharge current of each distributed electric box 120.

[0033] The box series relay 130 is connected in series between two adjacent distributed power boxes 120 .

[0034] The main control unit 140 is used to receive external control signals and control the box series relay 130 and the relays in the charge and discharge control circuit 110. The main control unit 140 has multiple pins that can be connected to the control coils of the corresponding relays to control the corresponding relays to be turned on or off. Through these pins, the relay can control high current or high voltage circuits without directly operating through switches, thereby achieving safe and effective electrical control.

[0035] The charge and discharge control circuit 110 refers to a control circuit circuit responsible for controlling the charging and discharging of the battery box, and has a relay inside. By controlling the on and off state of the relay, the charge and discharge control circuit 110 can manage the flow path of the current.

[0036] The distributed power box 120 refers to a power box dispersed in different parts of the battery system, which contains batteries, can store energy and provide power to the electric excavator. In the split battery system of the electric excavator, at least two distributed power boxes 120 are usually connected in series. In the embodiment of the present invention, only two are used as an example, which does not constitute a limit on the number of distributed power boxes 120.

[0037] The discharge main circuit refers to the main circuit in the battery system, which can ensure the effective transmission and use of electric energy. The box series relay 130 refers to an electrical switch device connected in series between two distributed power boxes 120, which can control the flow of current between the power boxes.

[0038] The main control unit 140 refers to the control unit of the battery system, which can receive external control signals and control the switching states of the box series relay 130 and the relays in the charge and discharge control circuit 110 according to these control signals, thereby controlling the flow path of the current in the circuit.

[0039] Specifically, the main control unit 140 can control the switching state of the box series relay 130. When the box series relay 130 is disconnected, the circuit is disconnected. Even if there is adhesion between the distributed electrical box 120 and the main circuit, the current cannot flow, which can prevent electric shock from occurring when the staff operates it incorrectly.

[0040] The technical solution provided by the embodiment of the present invention is to set a box series relay 130 in the main discharge circuit of the battery system, and control the switching state of the box series relay 130 through the main control unit 140 to realize the on and off of the main discharge circuit of the battery system, which can ensure that during the power-off process, the distributed electric box 120 is completely disconnected from the main discharge circuit, thereby avoiding the risk of electric shock and improving the safety of the circuit.

[0041] Figure 2 A schematic diagram of another split battery system for an electric excavator provided by an embodiment of the present invention. Figure 2 As shown, optionally, the electric excavator split battery system further includes: an upper box 150 , an upper box slave control 151 , at least one lower box 160 and at least one lower box slave control 161 .

[0042] The main control unit 140 , the upper box slave control 151 and the charge and discharge control circuit 110 are arranged in the upper box 150 ; the lower box slave control 161 and the box series relay 130 are arranged in the lower box 160 .

[0043] In the embodiment of the present invention, only one lower box 160 is used as an example for explanation, which does not constitute a limitation on the number of lower boxes 160. Among them, the upper box 150 refers to a packaging box of the split battery system of the electric excavator, which includes a main control unit 140, an upper box slave control 151 and a charge and discharge control circuit 110. The upper box slave control 151 refers to the control unit of the upper box 150, which is responsible for assisting the main control unit 140 in the management and monitoring of the battery system. For example, the upper box slave control 151 can send a control signal to the main control unit 140.

[0044] The lower box 160 refers to another package box of the split battery system of the electric excavator, which contains the lower box slave control 161 and the box series relay 130. The lower box slave control 161 refers to the control unit of the lower box 160, which is responsible for assisting the main control unit 140 in the management and monitoring of the battery system. Exemplarily, the lower box slave control 161 can send a control signal to the main control unit 140.

[0045] Continue to refer Figure 2 Optionally, the electric excavator split battery system also includes: at least two manual maintenance switches 170 connected in series to the main discharge circuit, and each manual maintenance switch 170 is respectively arranged in the upper box 150 and the lower box 160.

[0046] The manual maintenance switch 170 refers to an electrical switch used to cut off the power supply in the battery system. Usually, a manual maintenance switch 170 is placed in each box so as to cut off the power supply at different positions. After cutting off the manual maintenance switch 170, it is necessary to confirm that the power supply has been completely disconnected and there is no adhesion between the box and the power supply, otherwise there is a risk of electric shock.

[0047] According to the technical solution provided by the embodiment of the present invention, the upper box 150 and the lower box 160 have independent control units (upper box slave control 151 and lower box slave control 161), so that each box can independently monitor and manage the battery status and performance inside it. In addition, each box is provided with a manual maintenance switch 170, which can quickly cut off the power supply at different positions to ensure the safety of operators during maintenance and inspection and reduce the risk of electric shock. In addition, the main control unit 140 and the charge and discharge control circuit 110 are placed in the upper box 150, and work in conjunction with the lower box slave control 161, which can realize centralized monitoring and decentralized control, making the maintenance process of the battery system more efficient, and providing a strong guarantee for the safe operation and maintenance of the equipment.

[0048] Figure 3 A schematic diagram of another split battery system for an electric excavator provided by an embodiment of the present invention. Figure 3As shown, optionally, the charge and discharge control circuit 110 includes: a main positive relay 111, a main negative relay 112, a fuse 113 and a current sensor 114 connected in series on the discharge main circuit; wherein, the main positive relay 111 and the main negative relay 112 are controlled by the main control unit 140, and the current sensor 114 is used to send current acquisition information to the main control unit 140; wherein, one end of the main positive relay 111 is coupled to the discharge positive interface 180, and one end of the main negative relay 112 is coupled to the discharge negative interface 181.

[0049] The main positive relay 111 refers to an electrical switch used to control the flow of positive current in the main discharge circuit, which is controlled by the main control unit 140 and can control the connection and disconnection state of the power supply. The main negative relay 112 refers to an electrical switch used to control the flow of negative current in the main discharge circuit, which is controlled by the main control unit 140 and can control the connection and disconnection state of the power supply.

[0050] The fuse 113 refers to a protective device for preventing overload or short circuit in the circuit. When the current in the circuit exceeds the set value, the fuse 113 quickly melts, thereby cutting off the circuit and protecting the electrical equipment and lines from damage. The current sensor 114 refers to a device for monitoring the current flow in the circuit in real time, and sends the collected current information to the main control unit 140. Exemplarily, the current sensor 114 can be a Hall sensor.

[0051] The discharge positive interface 180 is the output port of the electric excavator battery system, responsible for transmitting the positive current of the battery to the load. One end of the main positive relay 111 is coupled to the discharge positive interface 180, which can control the output of the current. The discharge negative interface 181 corresponds to the discharge positive interface 180 and is the output port of the electric excavator battery system. One end of the main negative relay 112 is coupled to the discharge negative interface 181, which is used to connect the current return path of the load to ensure the complete circulation of the current.

[0052] Specifically, the main control unit 140 can achieve accurate management of current flow and ensure the safety and stable power supply of the battery by controlling the switch state of the main positive relay 111 and the main negative relay 112. The fuse 113 can protect the circuit from damage caused by overload and short circuit. At the same time, the current sensor 114 monitors the current state in the circuit in real time and uploads it to the main control unit 140 to ensure that the device operates within a safe working range.

[0053] Continue to see Figure 3 Optionally, in one embodiment, the split battery system for an electric excavator further includes: a pre-charging circuit, including a pre-charging relay 115 and a pre-charging resistor 116, the pre-charging relay 115 and the pre-charging resistor 116 are connected in series and in parallel with the main positive relay 111.

[0054] Among them, the pre-charge circuit is a circuit circuit set up to gradually charge the battery system when it is started to avoid instantaneous high current shock. The pre-charge relay 115 refers to a switching device that controls the pre-charge current and is controlled by the main control unit 140. The pre-charge resistor 116 refers to a resistor used to limit the pre-charge current, which can prevent excessive current from causing system damage. The pre-charge relay 115 and the pre-charge resistor 116 are connected in series to form a charging path for the pre-charge circuit.

[0055] In the embodiment of the present invention, the pre-charging circuit can be charged gradually before the battery system is started, thereby avoiding the impact of instantaneous high current on the battery and the device.

[0056] Continue to see Figure 3 Optionally, in one embodiment, the split battery system of the electric excavator also includes: a charging circuit, including a charging relay 117, one end of the charging relay 117 is coupled to the charging positive interface 182, and the other end of the charging relay 117 is coupled to the other end of the main positive relay 111; one end of the main negative relay 112 is also coupled to the charging negative interface 183.

[0057] Among them, the charging circuit refers to a circuit loop used to transfer electrical energy from an external power source to the battery for charging. The charging relay 117 refers to an electrical switch that controls the charging process and is controlled by the main control unit 140. The charging positive interface 182 is the input interface of the electric excavator battery system and is responsible for charging the battery. One end of the charging relay 117 is coupled to the charging positive interface 182 and can control the current flow path of the charging process. The charging negative interface 183 corresponds to the charging positive interface 182 and is coupled to one end of the main negative relay 112 to provide the negative return path of the charging current to the battery system.

[0058] In the embodiment of the present invention, through the control of the charging relay 117, the charging circuit can ensure that the battery can be charged quickly and safely when the external power supply is connected, so that the battery can quickly restore power supply when needed to meet the efficient operation requirements of the equipment.

[0059] Continue to see Figure 3 Optionally, in one embodiment, the electric excavator split battery system also includes: a heating circuit, including a heating relay 118, a discharge positive interface 180 and a charge positive interface 182 are both coupled to one end of the heating relay 118, and the other end of the heating relay 118 is coupled to the heating module 119.

[0060] Among them, the heating circuit refers to the battery circuit used to heat the battery system in a low temperature environment, which can ensure that the battery operates at an appropriate temperature and improve its performance and safety. The heating relay 118 refers to a switching device that controls the current of the heating circuit, and its switching state is controlled by the main control unit 140. The heating module 119 refers to the device that actually performs the heating function, which can provide the necessary heat for the battery to prevent performance degradation caused by low temperature. The heating circuit converts external AC power into DC power through a rectifier device, so that the heating module 119 is heated to the ideal temperature.

[0061] In the embodiment of the present invention, the heating circuit can ensure the performance of the battery in a low temperature environment. In cold working conditions, the heating module 119 can provide the necessary heat for the battery to ensure that it operates within a suitable temperature range, thereby avoiding the degradation of battery performance caused by low temperature.

[0062] The technical solution provided by the embodiment of the present invention controls the current flow state in the main discharge circuit through the main positive relay 111 and the main negative relay 112, and sets a pre-charging circuit, a charging circuit and a heating circuit in the main discharge circuit, so that the battery system is gradually charged before starting, and the charging speed and temperature are guaranteed. This solution can ensure the safe startup and efficient charging of the battery system, and work within a suitable temperature range.

[0063] The embodiment of the present invention also provides a control method for a split battery system for an electric excavator. The embodiment can be applied to the scenario of powering on and off the box of the electric excavator and charging. The method can be performed by the split battery system for the electric excavator, and the split battery system for the electric excavator can be configured in the electric excavator. The method includes: controlling the closing and disconnection of the relay in the charge and discharge control circuit and the box series relay according to a preset control logic.

[0064] The preset control logic refers to a series of rules and algorithms defined in the battery management system of an electric excavator, which are used to determine how to control the various components of the system under specific conditions. For example, the preset control logic includes controlling the opening and closing state of the relay in the charge and discharge control loop. When the relay is disconnected, no current flows in the circuit and the circuit is disconnected. When the corresponding relay is energized, the current in the circuit can flow and perform the corresponding function.

[0065] The technical solution provided by the embodiment of the present invention enables the relays and the box series relays in the charge and discharge control loop to be automatically energized or disconnected according to the system status through the implementation of preset control logic, thereby optimizing the battery charge and discharge process and improving the safety and reliability of the system.

[0066] Figure 4This is a flow chart of another control method of a split battery system for an electric excavator provided by an embodiment of the present invention. Based on the above embodiment, when the preset control logic is a power-on logic, such as Figure 4 As shown, optionally, the method includes:

[0067] S310: After the electric excavator is powered on, the main control unit is powered on and performs a wake-up self-check.

[0068] Among them, power-on refers to connecting the battery system to the power system of the electric excavator to provide the required power for the electrical components and drive system of the electric excavator. The external power-on signal refers to a signal from an external control device, an operator or other system, which is used to instruct the electric excavator or other electrical equipment to start the power supply or enter the working state. Optionally, the external power-on signal includes: the command issued by the vehicle control unit and the hard line power-on request is valid.

[0069] Wake-up self-test refers to a series of checks performed after the main control unit is powered on to confirm that all parts of the system are functioning normally. This includes monitoring the power supply, battery status, connection status, etc. to ensure that the device is within the normal operating range.

[0070] S320: After the wake-up self-test passes, the main control unit controls the cabinet series relay to be attracted through its corresponding pin.

[0071] Specifically, the main control unit has pins corresponding to the box series relays, and sends a low-level control signal through the corresponding pins to control the corresponding box series relays to be attracted, allowing current to flow between different battery boxes. This operation enables multiple parts of the battery system to be interconnected, ensuring that power can be effectively distributed to the required areas, preparing for subsequent operations.

[0072] S330, after receiving the external power-on signal, the main control unit controls the main negative relay and the pre-charge relay to be attracted through its corresponding pins.

[0073] Specifically, after receiving the external power-on signal, the main control unit will simultaneously control the main negative relay and the pre-charge relay to be energized. This operation connects the negative pole of the battery to the power-consuming device, allowing current to flow, and starts the pre-charge process to safely charge the battery and avoid instantaneous impact on the battery.

[0074] S340: If the pre-charge voltage reaches a preset percentage of the total voltage within the first preset time, the main control unit controls the main positive relay to close through the corresponding pin, and controls the pre-charge relay to open after the second preset time.

[0075] Among them, the pre-charge voltage refers to the voltage reached during the pre-charge process. The first preset time is the time for pre-charging that is specified in advance. Exemplarily, the first preset time can be 5 seconds. The preset percentage of the total voltage is the specific percentage that the battery voltage needs to reach during the pre-charge process, which is used to determine whether the battery charging state is appropriate. Exemplarily, the preset percentage of the total voltage can be ninety-five percent, ninety percent, etc. The second preset time refers to the time period set by the system after the main positive relay is closed. After this time period ends, the main control unit will control the pre-charge relay to disconnect to complete the pre-charge process. Exemplarily, the second preset time can be 200 milliseconds.

[0076] Specifically, the pre-charge voltage reaches a preset percentage of the total voltage within the first preset time, which can ensure that the battery has reached a certain pre-charge level before entering the normal charging state, which means that the battery is ready to accept higher voltage and current. When the pre-charge voltage reaches the standard, the main control unit controls the closing of the main positive relay, and the system switches from the pre-charge state to the normal working state. After the second preset time, the pre-charge relay is disconnected to prevent unnecessary current flow during the normal charging stage, protect the battery and system from overcharging or potential damage, and ensure the stability of the charging process.

[0077] In an embodiment of the present invention, if the main control unit does not receive an external power-on signal or the pre-charge voltage does not reach a preset percentage of the total voltage within the first preset time, and the number of pre-charges is greater than or equal to one, the main control unit sends a pre-charge fault signal, enters a fault handling procedure, and exits power-on.

[0078] The technical solution provided by the embodiment of the present invention controls the switching sequence of the main negative relay, the pre-charging relay and the main positive relay through the main control unit, so as to realize pre-charging first during the power-on process and then enter the normal working state, thereby avoiding the impact of instantaneous high current on the battery. At the same time, the pre-charging process can also enable the battery to reach a certain voltage level before entering the normal charging state, thereby improving the charging efficiency, shortening the charging time, and enabling the device to resume operation faster.

[0079] Figure 5 This is a flow chart of another control method of a split battery system for an electric excavator provided by an embodiment of the present invention. Based on the above embodiment, when the preset control logic is a power-off logic, such as Figure 5 As shown, optionally, the method includes:

[0080] S410: When the main control unit performs a circuit self-check and there is no fault, after receiving an external power-off signal, the main control unit controls the main positive relay to be disconnected through its corresponding pin.

[0081] Among them, power-off refers to the process of cutting off the connection between the battery system and the power supply and stopping the power supply. After the battery is powered off, the equipment stops running and all electronic components are powered off. The external power-off signal refers to a signal from an external control device, operator or other system, which is used to instruct the electric excavator or other electrical equipment to start the power supply or exit the working state. Optionally, the external power-off signal includes: the command issued by the vehicle control unit and the invalid hardline power-on request.

[0082] S420: After the third preset time, the main negative relay is disconnected by controlling the corresponding pin of the main control unit.

[0083] The third preset time refers to the waiting time set after the power-off signal is sent. The purpose of this time is to ensure that all system components have enough time to complete any necessary shutdown operations before completely powering off to avoid data loss or electrical failure. Exemplarily, the third preset time can be 200 milliseconds.

[0084] S430, disconnect the series relay of the cabinet through the corresponding pin of the main control unit.

[0085] In the embodiment of the present invention, if the self-check fails and the main control unit receives an external power-off signal, the main positive relay is disconnected through its corresponding pin, and the main negative relay is disconnected after the third preset time, and then the box series relay is disconnected. If the self-check fails and the main control unit does not receive an external power-off signal, it is determined whether the time of receiving the self-check fault signal exceeds the fourth preset time (exemplarily, the fourth preset time can be 10 seconds). If it exceeds, the main positive relay is disconnected, and the main negative relay is disconnected after the third preset time, and then the box series relay is disconnected.

[0086] The technical solution provided by the embodiment of the present invention controls the disconnection of the main positive relay, the main negative relay and the box series relay in sequence through the main control unit, so that the electric excavator can be safely powered off. This process not only ensures the safety and effective shutdown of the battery system, but also provides important support for the long-term stable operation and maintenance of the equipment, and improves the overall safety and reliability.

[0087] Figure 6 A flowchart of another control method of a split battery system for an electric excavator provided by an embodiment of the present invention. Based on the above embodiment, when the preset control logic is an AC / DC charging logic, such as Figure 6 As shown, optionally, the method includes:

[0088] S510: After receiving a charging gun insertion signal and a wake-up signal, the main control unit performs a wake-up self-check.

[0089] The charging gun insertion signal refers to the signal that the charging gun (or charging connector) has been successfully inserted into the charging port, which is usually triggered by the sensor or switch of the charging port, indicating that the external power connection has been established. The charging gun can be a DC charging gun to quickly charge the battery using DC power, or an AC charging gun to slowly charge the battery using AC power.

[0090] S520: After the wake-up self-test passes, the main control unit controls the cabinet series relay to be attracted through its corresponding pin.

[0091] Specifically, after the box series relay is energized, the battery box can be electrically connected to ensure the current flow between the boxes, providing the necessary power support for the normal operation of the electric excavator.

[0092] S530, the main control unit controls the main negative relay and the charging relay to be attracted through the corresponding pins according to the set charging process.

[0093] The charging process is a series of predefined operation steps and control logic in the electric excavator or other battery management system to manage the battery charging process. This process covers all aspects from the beginning to the end of charging, ensuring the safety, efficiency and reliability of the charging process.

[0094] S540: After detecting that the voltage of the single cell has reached the set voltage value, the main control unit controls the charging relay, the main negative relay and the box series relay to be disconnected through the corresponding pins.

[0095] Among them, a single cell refers to each independent battery unit in a battery pack. Each single cell has its own voltage and capacity, and a battery pack is usually composed of multiple single cells connected in series or in parallel to provide the required total voltage and capacity. The set voltage value refers to the voltage threshold pre-defined in the battery management system. When the voltage of the single cell reaches this value, the system will trigger the corresponding control operation, such as stopping charging or cutting off the power supply.

[0096] Specifically, when the single cell reaches the set voltage value, the system will automatically cut off the charging current to prevent the battery from overcharging, thereby protecting the safety and life of the battery. Disconnecting the main negative relay can effectively prevent the battery from accidentally discharging after charging is completed, ensuring that the battery remains charged in a safe state.

[0097] The technical solution provided by the embodiment of the present invention realizes the charging process of the electric excavator by controlling the switch state and switch sequence of the box series relay, the main negative relay and the charging relay through the main control unit. This solution can ensure the safety, stability and efficiency of the charging process, laying a foundation for the long-term stable operation of the equipment.

[0098] It should be noted that the exemplary examples provided in the embodiments of the present invention are intended to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0099] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0100] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A split battery system for an electric excavator, characterized in that: include: A charge and discharge control circuit and at least two distributed electric boxes, wherein the charge and discharge control circuit and each of the distributed electric boxes are connected in series to a main discharge circuit; the charge and discharge control circuit is used to control the flow path of the charge and discharge current of each of the distributed electric boxes; A box series relay is connected in series between two adjacent distributed electric boxes; A main control unit is used to receive an external control signal and control the box series relay and the relay in the charge and discharge control circuit.

2. The split battery system for electric excavators according to claim 1, characterized in that: Also includes: An upper box, an upper box slave control, at least one lower box and at least one lower box slave control; Among them, the main control unit, the upper box slave control and the charge and discharge control circuit are arranged in the upper box; the lower box slave control and the box series relay are arranged in the lower box.

3. The split battery system for electric excavators according to claim 2, characterized in that: Also includes: At least two manual maintenance switches are connected in series to the main discharge circuit, and each of the manual maintenance switches is arranged in the upper box and the lower box respectively.

4. The split battery system for electric excavators according to claim 1, characterized in that: The charge and discharge control circuit comprises: a main positive relay, a main negative relay, a fuse and a current sensor connected in series on the discharge main circuit; wherein the main positive relay and the main negative relay are controlled by the main control unit, and the current sensor is used to send current acquisition information to the main control unit; Among them, one end of the main positive relay is coupled to the discharge positive interface, and one end of the main negative relay is coupled to the discharge negative interface.

5. The split battery system for electric excavators according to claim 4, characterized in that: Also includes at least one of the following circuits: A pre-charging circuit, comprising a pre-charging relay and a pre-charging resistor, wherein the pre-charging relay and the pre-charging resistor are connected in series and then connected in parallel with the main positive relay; A charging circuit, comprising a charging relay, one end of which is coupled to the charging positive interface, and the other end of which is coupled to the other end of the main positive relay; one end of the main negative relay is also coupled to the charging negative interface; The heating circuit comprises a heating relay, the discharge positive interface and the charging positive interface are both coupled to one end of the heating relay, and the other end of the heating relay is coupled to the heating module.

6. A control method for a split battery system of an electric excavator, characterized in that: The electric excavator split battery system according to any one of claims 1 to 5 is adopted; the control method comprises: The relay in the charge and discharge control loop and the box series relay are controlled to be closed and cut off according to the preset control logic.

7. The control method of the split battery system for an electric excavator according to claim 6, characterized in that: The preset control logic is a power-on logic; the control of the relay in the charge-discharge control loop and the box series relay on and off according to the preset control logic includes: After the electric excavator is powered on, the main control unit is powered on and performs a wake-up self-test; After the wake-up self-test passes, the main control unit controls the box series relay to be attracted through its corresponding pin; After receiving the external power-on signal, the main control unit controls the main negative relay and the pre-charge relay to be attracted through its corresponding pins; If the pre-charge voltage reaches a preset percentage of the total voltage within the first preset time, the main control unit controls the main positive relay to close through the corresponding pin, and controls the pre-charge relay to open after the second preset time.

8. The control method of the split battery system for an electric excavator according to claim 6, characterized in that: The preset control logic is a power-off logic; and the control of the relay in the charge-discharge control loop and the box series relay on and off according to the preset control logic includes: When the main control unit performs a circuit self-check and there is no fault, after receiving an external power-off signal, the main control unit controls the main positive relay to be disconnected through its corresponding pin; After a third preset time, the main negative relay is disconnected by controlling the corresponding pin of the main control unit; The box series relay is disconnected by controlling the corresponding pin of the main control unit.

9. The control method of the split battery system for an electric excavator according to claim 7 or 8, characterized in that: The external power-on signal includes: a command issued by the vehicle control unit and a hard-line power-on request being valid; And / or, the external power-off signal includes: a command issued by a vehicle control unit and an invalid hardline power-on request.

10. The control method of the split battery system of an electric excavator according to claim 6, characterized in that: The preset control logic is an AC / DC charging logic; the control of the relay in the charging and discharging control loop and the box series relay on and off according to the preset control logic includes: The main control unit receives a charging gun insertion signal, and after receiving a wake-up signal, the main control unit performs a wake-up self-test; After the wake-up self-test passes, the main control unit controls the box series relay to be attracted through its corresponding pin; The main control unit controls the main negative relay and the charging relay to be attracted through the corresponding pins according to the set charging process; After detecting that the voltage of the single cell reaches the set voltage value, the main control unit controls the charging relay, the main negative relay and the box series relay to be disconnected through corresponding pins.

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