CN114844172A

CN114844172A - Battery switching system for unmanned vehicle

Info

Publication number: CN114844172A
Application number: CN202210627328.0A
Authority: CN
Inventors: 苏张勇
Original assignee: Neolix Technologies Co Ltd
Current assignee: Neolix Technologies Co Ltd
Priority date: 2022-06-02
Filing date: 2022-06-02
Publication date: 2022-08-02

Abstract

The present disclosure provides a battery switching system for an unmanned vehicle. The system is applied to an autonomous vehicle or an unmanned vehicle, and comprises: the system comprises two battery systems and a control unit, wherein the two battery systems are used for sequentially supplying power to the unmanned vehicle at high voltage, and each battery system comprises a blocking diode; when any one of the two battery systems is in a power supply state, if the electric quantity of the currently-supplied battery system is lower than a preset threshold value and the electric quantity of the other battery system is higher than another preset threshold value, the control unit controls the other battery system to be started, and the currently-supplied battery system and the other battery system simultaneously supply power to the unmanned vehicle; at the moment, the blocking diode can prevent the other battery system from charging the battery system which is currently supplied with power, and after the power supply state is maintained for a preset time, the control unit closes the battery system which is currently supplied with power to complete the switching between the two battery systems. The automatic battery replacement of the unmanned vehicle is realized, the battery replacement cost is reduced, the time consumed by battery replacement is shortened, and the battery replacement efficiency is improved.

Description

Battery switching system for unmanned vehicle

Technical Field

The present disclosure relates to the field of unmanned vehicles, and more particularly, to a battery switching system for an unmanned vehicle.

Background

An unmanned vehicle, also called an autonomous vehicle, an unmanned vehicle or a wheeled mobile robot, is an integrated and intelligent technical product integrating multiple elements such as environment perception, path planning, state recognition, vehicle control and the like, wherein the power of the unmanned vehicle is usually provided by a driving motor, and the energy is derived from a lithium battery. Receive the restriction of filling electric pile at present, the on-vehicle charging of unmanned car is very inconvenient, and on-vehicle charging time is longer simultaneously, influences the operation time. Therefore, the energy supply problem of the unmanned vehicle can be solved by adopting a mode of switching the battery system (namely, changing the battery).

At present, a battery switching system of an unmanned vehicle mainly comprises the following two switching modes: in the first switching mode, the complete battery system in the unmanned vehicle is replaced, but the complete battery system is large in size and weight and needs to be replaced in a fixed place by mechanical equipment, so that the battery replacing mode is high in battery replacing cost and long in battery replacing time, and the vehicle operation time is influenced; in the second switching mode, the complete battery system is split into a plurality of small battery packs, so that the weight of a single group of batteries is reduced, and the purpose of manually replacing the batteries is achieved.

Disclosure of Invention

In view of this, the embodiment of the present disclosure provides a battery switching system for an unmanned vehicle, so as to solve the problems in the prior art that the battery replacement cost is high, the battery replacement time is long, the battery replacement efficiency is low, and the safety of automatic driving and the vehicle operation time are affected.

The disclosed embodiment provides a battery switching system for unmanned vehicle, includes: the system comprises two battery systems and a control unit, wherein the two battery systems are used for sequentially supplying power to the unmanned vehicle at high voltage, and each battery system comprises a blocking diode; the control unit can acquire the electric quantity conditions of the two battery systems in real time, when any one of the two battery systems is in a power supply state, if the electric quantity of the currently-supplied battery system is lower than a preset threshold value and the electric quantity of the other battery system is higher than the other preset threshold value, the control unit controls the other battery system to be started, and the currently-supplied battery system and the other battery system simultaneously supply power to the unmanned vehicle; when the current power supply battery system and the other battery system supply power to the unmanned vehicle at the same time, the blocking diode of the current power supply battery system can prevent the other battery system from charging the current power supply battery system, and after the simultaneous power supply state is maintained for a preset time, the control unit closes the current power supply battery system to complete switching between the two battery systems.

The embodiment of the present disclosure adopts at least one technical scheme that can achieve the following beneficial effects:

sequentially supplying high-voltage power to the unmanned vehicle through two battery systems, wherein each battery system comprises a blocking diode; the control unit can acquire the electric quantity conditions of the two battery systems in real time, when any one of the two battery systems is in a power supply state, if the electric quantity of the currently-supplied battery system is lower than a preset threshold value and the electric quantity of the other battery system is higher than the other preset threshold value, the control unit controls the other battery system to be started, and the currently-supplied battery system and the other battery system simultaneously supply power to the unmanned vehicle; when the current power supply battery system and the other battery system supply power to the unmanned vehicle at the same time, the blocking diode of the current power supply battery system can prevent the other battery system from charging the current power supply battery system, and after the simultaneous power supply state is maintained for a preset time, the control unit closes the current power supply battery system to complete switching between the two battery systems. The utility model discloses an unmanned vehicles battery system's automatic switch-over, whole battery changing process need not manual operation, it is consuming time to have reduced and trade the electric cost and trade the electricity, greatly promoted and trade electric efficiency, trade the relay of the battery management unit in two battery systems of electricity in-process and can be closed simultaneously, it can guarantee that battery system's output current flows along a fixed direction to block the diode, and whole car can not cut off the power supply, can trade the electricity at the vehicle in-process that traveles, do not influence the vehicle and travel and vehicle operation time.

Drawings

To more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without inventive efforts.

Fig. 1 is a schematic view of the overall structure of a prior art unmanned vehicle battery system;

fig. 2 is a schematic overall structure diagram of a product of a battery switching system according to a first embodiment of the disclosure;

fig. 3 is a schematic diagram of an internal component structure of a battery switching system for an unmanned vehicle according to a first embodiment of the present disclosure;

fig. 4 is a schematic overall structure diagram of a product of a battery switching system according to a second embodiment of the disclosure;

fig. 5 is a schematic view of an internal component structure of a battery switching system for an unmanned vehicle according to a second embodiment of the present disclosure;

fig. 6 is a schematic battery swapping flow diagram of a battery switching system according to a first embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of an electronic device provided in an embodiment of the present disclosure.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the disclosed embodiments. However, it will be apparent to one skilled in the art that the present disclosure may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present disclosure with unnecessary detail.

As described in the background of the invention, as the technology of the unmanned vehicle matures with the development of the automatic driving technology and the new energy automobile technology, the application scenarios and the application range of the unmanned vehicle are gradually expanded, for example, the unmanned vehicle is divided into application scenarios including but not limited to an unmanned delivery vehicle, an unmanned retail vehicle, an unmanned sweeping vehicle, an unmanned patrol vehicle, and the like, and the unmanned vehicle may also be referred to as an automatic driving vehicle.

The automatic driving usually uses a new energy automobile as a carrier, so the power of the unmanned vehicle is usually provided by a driving motor, and the energy is derived from a lithium battery in a battery system. Receive the restriction of filling electric pile at present, the on-vehicle charging of unmanned car is very inconvenient, and on-vehicle charging time is longer simultaneously, influences the operation time. Therefore, the energy supply problem of the unmanned vehicle can be solved by switching the battery systems, and the switching process between the battery systems is also called a battery replacement process, and the battery replacement process refers to a process of switching from one battery pack (or battery system) to another battery pack (or battery system). Although the problem of energy supply of unmanned vehicles can be solved by battery replacement, the following problems still exist in the existing battery switching system:

in the first battery switching system in the prior art, a complete battery system with insufficient electric quantity in an unmanned vehicle is replaced by a battery system with sufficient electric quantity, but the complete battery system of the vehicle has large volume and weight, so that mechanical equipment is required to replace the complete battery system in a fixed place. For example, assuming that an unmanned vehicle needs more than 10kWh of electric energy after one-day operation, according to the current battery technology, the weight of a required battery system is at least more than 50kg, but the battery replacement of the 50kg battery system needs to be replaced by mechanical equipment, and the battery replacement needs to be performed in a fixed place, so that the construction investment of a battery replacement place is large, the time consumption for replacing the battery in the fixed place is long, and the operation time of the unmanned vehicle is influenced;

in the second battery switching system in the prior art, the complete battery system is split into a plurality of small battery packs, so that the weight of a single battery pack is reduced, and the purpose of manually replacing batteries is achieved. However, firstly, the battery changing method still needs manual operation, secondly, the relays between two groups of batteries cannot be closed simultaneously in the switching process, otherwise, when the relays between different battery packs are in a closed state simultaneously, the high-voltage battery pack is charged to the low-voltage battery pack, and the battery pack and the relays are damaged greatly.

In order to further explain the problems of the conventional battery switching system, the structure of the battery system in the prior art and the battery replacement method based on the structure will be described in detail below with reference to the accompanying drawings. Fig. 1 is a schematic view of an overall structure of a battery system of an unmanned vehicle in the prior art, and as shown in fig. 1, when a battery replacement operation is performed based on the battery system in the prior art, the following contents may be specifically included:

in the prior art, assuming that the cell capacity of the battery is 3.2Ah and the voltage platform is 3.6V, a battery system with a voltage platform of 72V and an electric quantity of 12.9kWh needs to be designed, and the battery system is generally designed as a battery system with 20 strings and 56 parallel in a whole pack. However, the weight of the battery system is up to 65kg calculated according to the maximum energy density of 200Wh/kg, so that the battery replacement (i.e. the replacement of the whole battery system) needs to be carried out by mechanical equipment, which causes great inconvenience to the actual operation of the unmanned vehicle.

Although, in the prior art, a battery system with a large weight can be split into a plurality of battery packs, the weight of a single battery pack is reduced, and manual battery replacement is convenient. For example, as shown in fig. 1, the battery system with a weight of 65kg is divided into four small battery packs, namely, a battery pack a, a battery pack B, a battery pack C and a battery pack D, and the battery packs are connected in parallel to form a new battery system.

However, firstly, the battery changing method still needs manual operation, secondly, when the parallel battery packs are switched, the relays of the two groups of batteries cannot be simultaneously closed, and after the two groups of batteries are simultaneously closed, because the voltages at the two ends of the high-voltage battery pack are different from the voltages at the two ends of the low-voltage battery pack, the high-voltage battery pack charges the low-voltage battery pack, and a large current is generated instantly, so that the BMU relays are adhered, and the service life of the batteries is shortened. Therefore, the relay of the low-voltage battery pack can be switched off only firstly, and the relay of the high-voltage battery pack can be switched on to work normally after the whole vehicle is powered off (namely, the vehicle is completely powered off). That is to say, in the prior art, when the battery is switched, the vehicle needs to be powered off to switch, so the battery can be replaced only when the vehicle is in a parking power-off state, and the battery cannot be automatically replaced in the vehicle running process. However, when the unmanned vehicle is powered off suddenly during driving, the vehicle loses power suddenly, and the safety of the unmanned vehicle during driving and automatic driving is greatly damaged. It should be noted that, powering down the vehicle is also referred to as powering down the high voltage, and powering up the vehicle is also referred to as powering up the high voltage, and variations of the same terms do not limit the technical solutions of the present disclosure.

In view of the problems in the prior art, the embodiments of the present disclosure provide an improved battery switching system for an unmanned vehicle, which is implemented based on the following principles: when the battery system of the unmanned vehicle is replaced, the relay of the battery management unit in the second battery system (namely, the other battery system) in the non-power supply state is closed, and at the moment, the BMU relays in the first battery system (namely, the currently-powered battery system) and the second battery system are simultaneously in a closed state. However, because the diodes are connected in series in the high-voltage loop of each battery system, the diodes are used for controlling the output current of the battery systems to flow along a fixed direction, and the high-voltage battery system is prevented from charging the low-voltage battery system, the whole vehicle can be switched without powering off, and the intelligent seamless switching of the battery systems is realized. The two battery system switching methods will be described in detail below with reference to specific embodiments.

Example one

First, the overall structure of a battery switching system according to a first embodiment of the present disclosure will be described with reference to the drawings. Fig. 2 is a schematic diagram of an overall structure of a battery switching system provided in an embodiment of the present disclosure, and as shown in fig. 2, the overall structure of the battery switching system may specifically include the following:

according to the characteristics of the lithium batteries and the technical characteristics of the battery management system, the battery system of the unmanned vehicle is subjected to modularization packet splitting design again, the battery system with large electric quantity and heavy weight is split into a plurality of battery packs, every two or more battery packs are connected in series to form one battery system, so that the whole battery system is divided into a plurality of battery systems with small scale, and the battery packs in each battery system can reach the weight of manually replacing the batteries (the battery system provided by the embodiment of the disclosure also supports manual battery replacement). When the two sets of battery systems are switched, the output current of the battery systems is controlled to flow along a fixed direction by the diodes connected in series on the high-voltage loop (the line corresponding to the thick line in the figure), so that the whole vehicle does not have high voltage during the battery replacement process, and the normal running of the vehicle is not influenced.

In a specific scenario, as shown in fig. 2, a previously complete battery system is split into 4 battery packs, wherein each 2 battery packs are connected in series to form one battery system, that is, each unmanned vehicle may be equipped with 4 battery packs, which together form two sets of battery systems connected in parallel, such as a battery system a and a battery system b. Taking a complete battery system with a voltage platform of 72V and an electric quantity of 12.9kWh as an example, the specific adopted splitting method may be to split a large battery pack of 12.9kWh into 4 small battery packs, such as a battery pack a, a battery pack B, a battery pack C and a battery pack D; the electric quantity of each battery pack is 3.2kWh, and a 10-string 28-parallel battery combination mode can be adopted, so that the voltage platform corresponding to each battery pack is 36V, and the weight is 17.5 kg. The battery pack A and the battery pack B are connected in series to form a battery system A, the battery pack C and the battery pack D are connected in series to form a battery system B, voltage platforms corresponding to the battery system A and the battery system B are both 72V, and electric quantity is both 6.45 kWh.

In the overall product structure of the battery switching system provided in the embodiment of the present disclosure, the battery switching system is composed of a VCU (Vehicle Control Unit) and two battery systems, where the Vehicle Control Unit VCU is an electric Control system of an unmanned Vehicle, and may also be referred to as a Control Unit, a Vehicle controller, or an electronic Control Unit, and is a core electronic Control Unit for implementing a Vehicle Control decision in the unmanned Vehicle, and may collect Vehicle information, Control Vehicle operation, diagnose Vehicle faults, and the like. The VCU of the embodiment of the present disclosure integrates a BCU (Battery Control Unit) and a BMS Battery system, and the BCU has a function of controlling the opening and closing of the main positive relay and the precharge relay according to feedback information of the BMU (Battery Management Unit) to realize the switching of the Battery.

Further, each battery pack comprises a BMU, and the BMU can acquire the cell voltage and the cell temperature of the battery pack and control the opening and closing of a relay of the BMU. The VCU can control the BMU to wake up and sleep through an activation signal, wherein the activation signal refers to a power supply signal transmitted through a circuit between the VCU and the BMU, and the BMU is controlled to wake up and sleep through a 12V power supply signal. The BMU may feed back information of the battery pack to the VCU through the CAN bus, for example, CAN1 and CAN2 in fig. 2 are respectively used to transmit information collected by the BMU of the battery pack in the battery system a and the battery system b, and the VCU may uniformly manage information of four groups of batteries.

Further, a blocking diode is connected in series to the high-voltage loops of the battery system a and the battery system b, respectively. A diode is a device with two electrodes that has a Rectifying (Rectifying) function, i.e. allows current to flow in only a single direction. The diode is utilized to ensure that the currents of the high-voltage battery system and the low-voltage battery system flow in one direction in the battery replacing process of the battery system, so that the high-voltage battery system cannot charge the low-voltage battery system, the BMU relay is ensured not to be adhered, and the service life of the battery is prevented from being reduced and the relay is prevented from being damaged.

It should be noted that, in the overall product structure of the battery switching system provided in the first embodiment of the present disclosure, two sets of parallel battery systems composed of four battery packs are taken as an example for description, and therefore, the following specific embodiment takes a switching process from the battery system a to the battery system b as an example for description, that is, the battery system a is taken as a low-voltage battery system with insufficient remaining power, and the battery system b is taken as a high-voltage battery system with sufficient power. However, it should be understood that the battery system switching method according to the embodiment of the present disclosure is not limited to a switching scenario of two sets of battery systems, and when an unmanned vehicle includes more than two sets of battery systems, the battery systems may still be switched by using the technical solution of the present disclosure, and the number of the battery systems does not limit the technical solution of the present disclosure. The technical scheme of the disclosure is explained in detail by combining specific embodiments.

Fig. 3 is a schematic view of an internal component structure of a battery switching system for an unmanned vehicle according to a first embodiment of the present disclosure. As shown in fig. 3, the battery switching system for an unmanned vehicle may specifically include:

two battery systems, namely a first battery system 301 and a second battery system 302, and a control unit 303, wherein the two battery systems are used for sequentially supplying power to the unmanned vehicle at high voltage, and each battery system comprises a blocking diode 304; the control unit 303 can obtain the power statuses of the two battery systems in real time, and when any one of the two battery systems is in a power supply state, if the power of the currently-supplied battery system (i.e., the first battery system 301) is lower than a predetermined threshold and the power of the other battery system (i.e., the second battery system 302) is higher than another predetermined threshold, the control unit 303 controls the other battery system to be started, and the currently-supplied battery system and the other battery system supply power to the unmanned vehicle at the same time; when the currently-supplied battery system and the other battery system supply power to the unmanned vehicle at the same time, the blocking diode 304 of the currently-supplied battery system can prevent the other battery system from charging the currently-supplied battery system, and after the simultaneous power supply state is maintained for a predetermined time, the control unit 303 closes the currently-supplied battery system to complete switching between the two battery systems.

Specifically, a currently-powered battery system may also be referred to as a first battery system, another battery system may also be referred to as a second battery system, and the substitution on the terminology does not limit the technical solution of the present disclosure. The first battery system 301 includes at least one battery pack, a first relay 305 connected to the battery pack, and a first battery management unit 306 for controlling the first relay 305 to open and close; the second battery system 302 also includes at least one battery pack, a second relay 307 connected to the battery pack, and a second battery management unit 308 for controlling the second relay 307 to open and close.

Further, the battery system switching of the embodiments of the present disclosure may be considered as switching the energy supply battery of the unmanned vehicle from one battery system to another battery system. The battery system before the battery replacement can be a battery system which is supplying energy for the unmanned vehicle at present, namely, the battery system can be called as an energy supply battery system, when the residual electric quantity of the current energy supply battery system of the unmanned vehicle is reduced, the voltage at two ends of the energy supply battery system is reduced, in order to enable the unmanned vehicle to continuously run and work, the energy supply battery system of the unmanned vehicle needs to be switched into a high-voltage battery system with sufficient electric quantity from a low-voltage battery system with insufficient electric quantity, and the switching process of the battery system can be called as battery replacement.

Further, in the battery replacement process of the battery system, firstly, the control unit is used for sending a closing instruction to the BMU of the target battery system (namely, the second battery system) through the CAN bus to close the BMU relay of the target battery system, and as the BMU relay of the energy supply battery system (namely, the first battery system) is also in a closed state, at the moment, diodes installed on the high-voltage loops of the target battery system and the energy supply battery system start to work, so that the currents of the target battery system and the energy supply battery system are controlled to flow to one direction, and the high-voltage battery system is prevented from charging the low-voltage battery system.

According to the technical scheme provided by the first embodiment of the disclosure, the blocking diode is arranged on the high-voltage loop of the battery system in the unmanned vehicle, and the characteristic that the blocking diode controls the current direction is utilized, so that when the two battery systems are switched, the high-voltage battery system cannot charge the low-voltage battery system, and then the BMU relay of the previous energy supply battery system is switched off after the target battery system is switched, so that the unmanned vehicle cannot be powered off in the whole power exchange process. Therefore, the battery can be replaced in the unmanned vehicle running process, the vehicle running and vehicle operation time is not influenced, the battery replacing process is automatic operation, the battery replacing cost is reduced, the battery replacing time is shortened, and the battery replacing efficiency is greatly improved.

In some embodiments, the battery system includes a battery management unit for controlling opening and closing of the relay, the battery system being closed when the relay is open, and the battery system being open when the relay is closed.

Specifically, a battery management unit and a relay are installed in each battery system, the battery management unit is connected with the relay in series, and the battery management unit is used for controlling the opening and closing of the relay according to a CAN signal sent by a control unit VCU through a CAN bus.

In some embodiments, each battery system comprises one or more battery packs connected in series, each battery pack is provided with a battery management unit, and the battery systems have a parallel connection relationship.

Specifically, each battery system may include at least one battery pack, and a plurality of battery packs in the same battery system may have a series relationship therebetween and a parallel relationship between different battery systems.

In some embodiments, the battery management unit is for controlling opening and closing of the relay, comprising: the control unit is also used for sending an opening signal or a closing signal to a battery management unit in the battery system through a CAN bus connected with the battery system, and the battery management unit controls the opening and closing of the relay according to the opening signal or the closing signal.

Specifically, when the other battery system is started, the control unit is used for sending a closing instruction to a second battery management unit in the other battery system (namely, a second battery system) so that the second battery management unit controls the second relay to be closed. In practical application, the control unit is used for sending the closing instruction to the second battery management unit in a CAN signal mode through a CAN bus connected with the second battery system, and the second battery management unit controls the relay of the second battery management unit to be closed based on the closing instruction.

Further, before the power change operation of the unmanned vehicle, the first battery system is in a normal working state, the BMU relays of the battery packs in the first battery system are all in a closed state, and the BMU relays in the second battery system in a non-power supply state are all in an open state. In order to switch the battery system from the first battery system to the second battery system, the VCU is first used to send a close command to each second battery management unit (abbreviated as a second BMU) in the second battery system, so as to control all the second BMUs to close their BMU relays.

For example, suppose that the second battery system a includes a battery pack C and a battery pack D, the VCU sends a CAN signal carrying a close command to the second BMU of the battery pack C and the battery pack D through the CAN2 bus, and after receiving the CAN signal, the second BMU of the battery pack C and the battery pack D controls the respective BMU relays to close, and at this time, all the battery packs in the battery system b start to discharge.

Similarly, after the second BMU relay in the target battery system is closed by the control unit VCU, the target battery system enters a power supply state, that is, the target battery system starts to supply power to the unmanned vehicle through the high-voltage loop. Therefore, the unmanned vehicle energy supply battery system before power change no longer supplies power to the unmanned vehicle, and at the moment, the control unit VCU sends a disconnection instruction to the first BMUs to enable all the first BMUs to disconnect the relays of the first BMUs so as to control the first battery system to be changed from the power supply state to the non-power supply state.

For example, suppose that the first battery system a includes a battery pack a and a battery pack B, the VCU sends a CAN signal carrying a close command to a first BMU of the battery pack a and the battery pack B through a CAN1 bus, and after receiving the CAN signal, the first BMU of the battery pack a and the battery pack B controls respective BMU relays to open, and at this time, all battery packs in the battery system a stop discharging.

In some embodiments, the control unit is configured to, during operation of the unmanned vehicle, acquire remaining power information of a currently-powered battery system and another battery system, and switch the currently-powered battery system when the remaining power of the currently-powered battery system is lower than a predetermined threshold and the remaining power of the another battery system is higher than another predetermined threshold, where the predetermined threshold is 20% of the remaining power.

Specifically, before the battery replacement of the unmanned vehicle battery system, it is first determined whether the battery system currently supplying power needs to be switched, that is, whether the battery replacement operation is performed on the battery system currently supplying power. In practical application, the BMUs in each battery system report the remaining power information of each battery pack to the control unit VCU, and the control unit VCU determines the remaining power of the battery system according to the remaining power information of all the battery packs in the battery system, and determines whether battery replacement is needed based on the remaining power of the battery system.

Further, when the judgment is performed based on the remaining power, the remaining power corresponding to the currently-powered battery system and the remaining power corresponding to the other battery system are calculated according to the remaining power of each battery pack reported by the BMU in each battery system, and when the remaining power of the first battery system (i.e., the currently-powered battery system) is lower than a predetermined threshold and the remaining power of the second battery system (i.e., the other battery system) is higher than another predetermined threshold, it is judged that the currently-powered battery system of the unmanned vehicle is switched.

In practical applications, the remaining capacity may be the SOC of the battery system, the predetermined threshold may be set to 20%, the other predetermined threshold may be set to 50%, and when the SOC of the first battery system is less than 20% and the SOC of the second battery system is greater than 50%, the battery replacement of the battery system is started. SOC is a state of charge, which reflects the remaining capacity of the battery, and is numerically defined as the ratio of the remaining capacity to the battery capacity, expressed in percent; the SOC of the battery can be estimated by using parameters such as terminal voltage, charge/discharge current, and internal resistance of the battery. It should be noted that, in the above embodiment, the SOCs corresponding to the predetermined threshold and the another predetermined threshold are set to 20% and 50%, respectively, but it should be understood that the setting of the threshold is only a preferred implementation manner, and in a real application, the size of the threshold may be customized according to an actual requirement, for example, the another predetermined threshold may also be set to 40%. Typically, the further predetermined threshold value should be higher than the predetermined threshold value.

In some embodiments, when the number of the battery systems in the non-power supply state is more than one, that is, when a plurality of second battery systems are included, the battery control unit selects one battery system as the target battery system for the switching from the second battery systems in the non-power supply state.

Specifically, the control unit VCU may calculate the remaining power corresponding to each battery system in the non-power supply state according to the remaining power of each battery pack reported by the BMUs of each battery system in the non-power supply state, sort the battery systems in the non-power supply state according to the remaining power, select the battery system in the non-power supply state with the lowest remaining power as the target battery system, and select the battery system b as the target battery system in the embodiment of the present disclosure.

In some embodiments, the blocking diode is used for controlling the output current of the currently-powered battery system and the other battery system to flow along the power supply direction of the unmanned vehicle from the positive pole when the currently-powered battery system and the other battery system are simultaneously started, wherein the blocking diode is connected in series on a high-voltage loop of each battery system, and the high-voltage loop is connected with the power supply circuit of the unmanned vehicle.

Specifically, the blocking diodes connected in series with the first battery system and the second battery system are respectively used for controlling the output currents of the first battery system and the second battery system to flow along a fixed direction, namely when the relay of the first battery management unit and the relay of the second battery management unit are simultaneously in a closed state, the blocking diodes are used for respectively controlling the output currents of the first battery system and the second battery system to flow along the power supply direction from the positive electrode to the unmanned vehicle; the diodes are connected in series on a high-voltage loop of each battery system, and the high-voltage loop is connected with a power supply circuit of the unmanned vehicle.

Further, the first battery system is always in a discharging state before and during battery replacement, that is, a BMU relay of a first battery management unit (simply referred to as a first BMU) in the first battery system is in a closed state; meanwhile, after the control unit VCU sends a close command to the second BMU, the BMU relay of the second BMU also enters a closed state, and thus, the BMU relays in the first battery system and the second battery system are both in the closed state.

Further, when the first BMU relay and the second BMU relay are simultaneously in a closed state, since the voltage of the second battery system is higher than that of the first battery system, in order to prevent the second battery system from charging the first battery system, at this time, the diodes connected in series to each high-voltage loop are used to control the output currents of the first battery system and the second battery system to flow in one direction, so that the high-voltage battery system can be prevented from charging the low-voltage battery system. In practical application, each battery system is connected with a high-voltage loop, the high-voltage loop can be led out from one battery pack in each battery system, one end of the high-voltage loop is connected with the anode of one battery pack in the battery system, and the other end of the high-voltage loop is connected with a power supply circuit of the unmanned vehicle and used for transmitting electric energy to a driving motor controller of the unmanned vehicle and other electric appliances.

Further, after the control unit VCU controls the first BMU relay to be turned off, the power supply of the unmanned vehicle is completely provided by the second battery system, and at this time, the power supply battery system of the unmanned vehicle is switched from the first battery system to the second battery system, and the whole power switching process of the unmanned vehicle is completed.

The above is a detailed description of the technical solution provided by the first embodiment of the present disclosure, and the technical solution of the first embodiment of the present disclosure will be described in detail with reference to specific contents.

Example two

First, an overall structure of a battery switching system according to a second embodiment of the present disclosure will be described with reference to the drawings. Fig. 4 is a schematic diagram of an overall structure of a battery switching system provided in the second embodiment of the present disclosure, and as shown in fig. 4, the overall structure of the battery switching system may specifically include the following:

compared with the overall structure of the battery system provided in the first embodiment, the battery switching system and the battery pack dividing and combining manner, the connection manner between the high-voltage loop and the battery system, the connection relationship between the diode and the high-voltage loop, the installation positions and structures of the control unit VCU and the BMU relay in the battery system, and the like in the second embodiment of the present disclosure have the same structure as those in the first embodiment. Therefore, the same structure is not described again, but the difference is that in the battery switching system of the second embodiment, a switching relay is connected in parallel to the diode of each high-voltage loop. The switching relay has the advantages that after the power switching operation is completed, the switching relay is closed, so that the current on the high-voltage loop passes through the switching relay end and does not pass through the diode, the power loss of the diode can be reduced, and the problem that the diode stops working due to overhigh temperature caused by long-time working of the diode is avoided. Based on the overall product structure of the battery switching system of fig. 4, the following describes in detail the technical solution of the second embodiment of the present disclosure.

Fig. 5 is a schematic view of an internal component structure of a battery switching system for an unmanned vehicle according to a second embodiment of the present disclosure. As shown in fig. 5, the battery switching system for an unmanned vehicle may specifically include:

the system comprises two battery systems, namely a first battery system 501 and a second battery system 502, and a control unit 503, wherein the two battery systems are used for sequentially supplying high-voltage power to the unmanned vehicle, and each battery system comprises a blocking diode 504 and a switching relay 509 connected in parallel to the blocking diode 504; the control unit 503 can obtain the power conditions of the two battery systems in real time, when any one of the two battery systems is in a power supply state, if the power of the currently-supplied battery system (i.e., the first battery system 501) is lower than a predetermined threshold and the power of the other battery system (i.e., the second battery system 502) is higher than another predetermined threshold, the control unit 503 controls the other battery system to be turned on and controls the switching relay 509 of the first battery system 501 to be turned off, and the currently-supplied battery system and the other battery system simultaneously supply power to the unmanned vehicle; when the currently-supplied battery system and another battery system supply power to the unmanned vehicle at the same time, the blocking diode 504 of the currently-supplied battery system can prevent the other battery system from charging the currently-supplied battery system, and after the state of the above-mentioned simultaneous power supply is maintained for a predetermined time, the control unit 503 closes the currently-supplied battery system and controls the switching relay 509 of the second battery system 502 to be closed, thereby completing the switching between the two battery systems.

Specifically, in the battery switching system according to the second embodiment of the present disclosure, the installation positions and the installation manners of the first relay 505, the first battery management unit 506, the second relay 507, and the second battery management unit 508 are the same as those of the battery switching system according to the first embodiment, and thus are not described again.

The second technical scheme of the embodiment of the present disclosure is an improvement on the first technical scheme of the embodiment, and in the first embodiment, a diode is connected in series with a high-voltage loop of each battery system, so that when the two battery systems are switched, currents of the high-voltage battery system and the low-voltage battery system both flow in one direction, and therefore the high-voltage battery system is prevented from charging the low-voltage battery system. However, in the whole power exchanging process and after the power exchanging is completed, the diode is always in the working state, the diode per se has power loss, for example, a 72V battery system has 1% power loss, the diode can lose energy and generate heat after working for a long time, and the diode can stop working after reaching a certain temperature if heat dissipation is not good. Therefore, in order to avoid this problem, in the embodiments of the present disclosure, a switching relay is connected in parallel to each diode, and after the switching operation is completed by using the diodes, the switching relay connected in parallel to the diodes is closed, so that the current passes through the switching relay terminal and does not pass through the diode terminal, which greatly reduces the operating time of the diodes, thereby reducing the power loss of the diodes after the switching.

In some embodiments, the battery system further comprises a switching relay, the switching relay is connected with the blocking diode in parallel, and when the currently-powered battery system and another battery system are in an on state at the same time, the switching relay is turned off; when any battery system is in a power supply state for the unmanned vehicle, the switching relay of the battery system which supplies power currently is closed, and the switching relay of the other battery system is opened.

Specifically, when the current power supply battery system supplies power to the unmanned vehicle, a relay of a first battery management unit in the first battery system is in a closed state, and a switching relay on a diode connected in series with the first battery system is in a closed state; the relay of the battery management unit in the second battery system in the non-power supply state is in an off state, and the switching relay on the diode connected in series with the second battery system in the non-power supply state is in an off state.

Further, before the battery replacement is carried out, the first battery system is in a normal working state, and the second battery system is in a non-working state, so that the BMU relays of the battery pack A and the battery pack B in the battery system A and the switching relays of the diodes in the battery system A in the normal working state are both in a closed state; the battery pack C in the battery system B, the BMU relay of the battery pack D and the switching relay of the diode are all in an off state, at the moment, the battery system A supplies power to the unmanned vehicle, and the power supply current passes through the first switching relay.

In some embodiments, the control unit controls the switching relay of the currently-supplied battery system to be opened after controlling the relay of the other battery system to be closed, and the control unit controls the switching relay of the other battery system to be closed after controlling the relay of the currently-supplied battery system to be opened, when the output current of the other battery system supplies power to the unmanned vehicle through the closed switching relay.

Specifically, when the battery switching system of the second embodiment of the present disclosure determines that the battery system of the unmanned vehicle needs to be switched, the control unit VCU is first used to send a control signal to the switching relay of the first battery system, for example, the switching relay is controlled to be opened by a connection circuit with the switching relay of the first battery system, and then the control unit VCU sends a close command to each second BMU in the second battery system, so as to control all the second BMUs to close their BMU relays. At the moment, BMU relays in the first battery system and the second battery system are both in a closed state, the voltage of the second battery system is higher than that of the first battery system, and in order to avoid charging the first battery system by the second battery system, the current of the first battery system and the current of the second battery system are controlled to flow in one direction by using diodes.

Then, the control unit VCU sends an off command to each first BMU in the first battery system, and after receiving the off command, the first BMU controls the first BMU relay to be turned off, and at this time, the first battery system stops discharging. The whole power supply of the unmanned vehicle is provided by the second battery system, the power supply current output by the second battery system passes through the diode, and in order to avoid that the diode stops working due to overhigh temperature caused by the long-time working state after the battery replacement operation is completed, the control unit VCU sends a control signal to the switching relay of the second battery system, and the switching relay of the second battery system is closed, so that the power supply current output by the second battery system passes through the switching relay instead of the diode.

According to the above description of the second technical solution of the second embodiment of the present disclosure, the battery switching system of the second embodiment of the present disclosure is different from the battery switching system of the first embodiment in that: in the second embodiment, each diode is connected with a switching relay in parallel, and in a normal working state, the switching relay of the energy supply battery system is in a closed state, and the power supply current of the energy supply battery system passes through the switching relay; therefore, in order to operate the diodes of all the battery systems during the battery replacement process, the switching relay of the energy supply battery system needs to be disconnected first, and current needs to be passed through the diodes. After the battery replacement operation is completed, the switching relay of the other battery system which is in the open state before the battery replacement operation is closed, and the power supply current of the other battery system passes through the switching relay.

It should be noted that the differences between the second embodiment of the present disclosure and the first embodiment are mainly used as objects of description, but the second embodiment of the present disclosure should not be considered to include only the above-mentioned contents. It should be understood that, except for the above differences, other technical means are completely the same as the contents of the first embodiment, so that the contents of the same portions may refer to the descriptions of the first embodiment, and the contents of the same portions between the two embodiments are not repeated in the second embodiment of the disclosure.

According to the second technical scheme provided by the embodiment of the disclosure, in order to avoid the problem that the diode stops working due to overhigh temperature caused by power loss caused by long-time working of the diode, the switching relay is connected in parallel with the diode, when the battery replacement operation starts, the control unit VCU is firstly used for disconnecting the switching relay of the primary energy supply battery system to enable the current of the primary energy supply battery system to pass through the diode, the characteristic that the diode controls the current direction is used for enabling the high-voltage battery system not to charge the low-voltage battery system in the switching process of the two battery systems, and after the switching is carried out to the target battery system, the control unit VCU is used for closing the switching relay of the target battery system to enable the current of the target battery system to pass through the switching relay. The power supply switching method and the power supply switching device ensure that the unmanned vehicle cannot be powered off in the whole power switching process, can switch power in the unmanned vehicle running process, and do not influence the vehicle running time and the vehicle operation time; the working life of the diode is prolonged, the battery replacement process is automatic operation, the battery replacement cost is reduced, the time consumed by battery replacement is shortened, and the battery replacement efficiency is greatly improved.

The foregoing embodiment describes in detail the structure and principle of the battery switching system of the unmanned vehicle of the present disclosure, and the following briefly describes a flow of replacing the battery of the unmanned vehicle by using the battery switching system of the first embodiment with reference to the battery switching system of the first embodiment.

Fig. 6 is a schematic battery swapping flow diagram of a battery switching system according to a first embodiment provided in the present disclosure. As shown in fig. 6, the unmanned vehicle battery system switching method may specifically include:

s601, when the battery system in the unmanned vehicle is judged to reach a preset switching condition, determining a first battery system in a power supply state, and selecting a second battery system from the battery systems in a non-power supply state;

s602, sending a closing instruction to a second battery management unit in a second battery system by using the control unit so as to close a relay of the second battery management unit;

s603, controlling the output currents of the first battery system and the second battery system to flow along a fixed direction by using diodes respectively connected with the first battery system and the second battery system in series;

and S604, sending an opening instruction to a first battery management unit in the first battery system by using the control unit so as to open a relay of the first battery management unit, and switching the battery system of the unmanned vehicle from the first battery system to a second battery system.

It should be noted that the battery system switching method shown in fig. 6 is based on the battery swapping method flow of the battery switching system provided in the first embodiment, and when the battery switching system provided in the second embodiment performs a battery swapping operation, the operation flow is basically similar to the above method flow, except that when it is determined that the battery system in the unmanned vehicle reaches a predetermined switching condition, the battery swapping relay of the first battery system is controlled to be opened by the control unit, and after the control unit sends an opening instruction to the first battery management unit in the first battery system, the battery swapping relay of the second battery system is controlled to be closed by the control unit.

It should be understood that, the sequence numbers of the steps in the foregoing method embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present disclosure.

Fig. 7 is a schematic structural diagram of an electronic device 7 according to an embodiment of the present disclosure. As shown in fig. 7, the electronic apparatus 7 of this embodiment includes: a processor 701, a memory 702, and a computer program 703 stored in the memory 702 and executable on the processor 701. The steps in the above-described method embodiments are implemented when the processor 701 executes the computer program 703. Alternatively, the processor 701 implements the functions of each module/unit in each device embodiment described above when executing the computer program 703.

Illustratively, the computer program 703 may be partitioned into one or more modules/units, which are stored in the memory 702 and executed by the processor 701 to accomplish the present disclosure. One or more modules/units may be a series of computer program instruction segments capable of performing specific functions, which are used to describe the execution of the computer program 703 in the electronic device 7.

The electronic device 7 may be a desktop computer, a notebook, a palm computer, a cloud server, or other electronic devices. The electronic device 7 may include, but is not limited to, a processor 701 and a memory 702. Those skilled in the art will appreciate that fig. 7 is merely an example of the electronic device 7, does not constitute a limitation of the electronic device 7, and may include more or less components than those shown, or combine certain components, or different components, e.g., the electronic device may also include input-output devices, network access devices, buses, etc.

The Processor 701 may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The storage 702 may be an internal storage unit of the electronic device 7, for example, a hard disk or a memory of the electronic device 7. The memory 702 may also be an external storage device of the electronic device 7, such as a plug-in hard disk provided on the electronic device 7, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like. Further, the memory 702 may also include both an internal storage unit of the electronic device 7 and an external storage device. The memory 702 is used to store computer programs and other programs and data required by the electronic device. The memory 702 may also be used to temporarily store data that has been output or is to be output.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules, so as to perform all or part of the functions described above. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the above embodiments, the description of each embodiment has its own emphasis, and reference may be made to the related description of other embodiments for parts that are not described or recited in any embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

In the embodiments provided in the present disclosure, it should be understood that the disclosed apparatus/computer device and method may be implemented in other ways. For example, the above-described apparatus/computer device embodiments are merely illustrative, and for example, a division of modules or units, a division of logical functions only, an additional division may be made in actual implementation, multiple units or components may be combined or integrated with another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present disclosure may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated modules/units, if implemented in the form of software functional units and sold or used as separate products, may be stored in a computer readable storage medium. Based on such understanding, the present disclosure may implement all or part of the flow in the method of the above embodiments, and may also be implemented by a computer program to instruct related hardware, where the computer program may be stored in a computer readable storage medium, and when the computer program is executed by a processor, the steps of the above method embodiments may be implemented. The computer program may comprise computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying computer program code, recording medium, usb disk, removable hard disk, magnetic disk, optical disk, computer Memory, Read-only Memory (ROM), Random Access Memory (RAM), electrical carrier wave signals, telecommunications signals, software distribution medium, and the like. It should be noted that the computer readable medium may contain suitable additions or additions that may be required in accordance with legislative and patent practices within the jurisdiction, for example, in some jurisdictions, computer readable media may not include electrical carrier signals or telecommunications signals in accordance with legislative and patent practices.

The above examples are only intended to illustrate the technical solutions of the present disclosure, not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present disclosure, and they should be construed as being included in the scope of the present disclosure.

Claims

1. A battery switching system for an unmanned vehicle, comprising: the unmanned vehicle comprises two battery systems and a control unit, wherein the two battery systems are used for sequentially supplying high-voltage power to the unmanned vehicle, and each battery system comprises a blocking diode; the control unit can acquire the electric quantity conditions of the two battery systems in real time, when any one of the two battery systems is in a power supply state, if the electric quantity of the currently-supplied battery system is lower than a preset threshold value and the electric quantity of the other battery system is higher than the other preset threshold value, the control unit controls the other battery system to be started, and the currently-supplied battery system and the other battery system simultaneously supply power to the unmanned vehicle;

when the current power supply battery system and the other battery system supply power to the unmanned vehicle at the same time, the blocking diode of the current power supply battery system can prevent the other battery system from charging the current power supply battery system, and after the state of the simultaneous power supply is maintained for a preset time, the control unit closes the current power supply battery system to complete the switching between the two battery systems.

2. The system of claim 1, wherein the battery system comprises a battery management unit and a relay, the battery management unit is configured to control the opening and closing of the relay, the battery system is closed when the relay is open, and the battery system is open when the relay is closed.

3. The system of claim 2, wherein each of said battery systems comprises one or more battery packs connected in series, one of said battery management units being disposed in each of said battery packs, said battery systems having a parallel relationship therebetween.

4. The system of claim 2, wherein the battery management unit is configured to control opening and closing of the relay, comprising:

the control unit is also used for sending an opening signal or a closing signal to the battery management unit in the battery system through a CAN bus connected with the battery system, and the battery management unit controls the opening and closing of the relay according to the opening signal or the closing signal.

5. The system according to claim 1, wherein the control unit is configured to obtain remaining capacity information of the currently-powered battery system and the another battery system during operation of the unmanned vehicle, and switch the currently-powered battery system when the remaining capacity of the currently-powered battery system is lower than the predetermined threshold and the remaining capacity of the another battery system is higher than the another predetermined threshold, where the predetermined threshold is 20% of the remaining capacity.

6. The system of claim 1, wherein the blocking diode is configured to control the output current of the currently-powered battery system and the other battery system to flow in a direction of positive power supply to the unmanned vehicle when the currently-powered battery system and the other battery system are simultaneously turned on, and the blocking diode is connected in series with a high voltage loop of each battery system, and the high voltage loop is connected to a power supply circuit of the unmanned vehicle.

7. The system of claim 1, wherein the battery system further comprises a switching relay connected in parallel with the blocking diode, the switching relay being open when both the currently powered battery system and the other battery system are simultaneously on; when any battery system is in a power supply state for the unmanned vehicle, the switching relay of the currently-powered battery system is closed, and the switching relay of the other battery system is opened.

8. The system according to claim 7, wherein the control unit controls the switching relay of the currently-supplied battery system to be opened after controlling the relay of the other battery system to be closed, and the control unit controls the switching relay of the other battery system to be closed after controlling the relay of the currently-supplied battery system to be opened, when the output current of the other battery system supplies power to the unmanned vehicle through the closed switching relay.

9. The system of any one of claims 1-8, wherein the control unit comprises a Vehicle Control Unit (VCU), the battery management unit comprises a BMU unit, and the relay corresponding to the BMU unit is a BMU relay.