New energy commercial vehicle slow charging system and slow charging method thereof

Abstract

The application discloses a new energy commercial vehicle slow charging system and a slow charging method thereof, and the system comprises a vehicle-mounted charger, a vehicle controller, a battery management system, a multi-in-one control box, a conversion controller and a European and American standard charging pile, the vehicle controller, the battery management system, the vehicle-mounted charger and the multi-in-one control box are connected to a vehicle EVCAN network; the battery management system communicates with the conversion controller through a national standard charging CAN network; the conversion controller communicates with the European and American standard charging pile through a CP carrier signal; a European and American standard charging gun of the European and American standard charging pile is connected with the vehicle-mounted charger, and the vehicle-mounted charger is also connected with the multi-in-one control box. The new energy commercial vehicle slow charging system and the slow charging method thereof provided by the application can realize European and American standard charging by only adding OBC control logic in combination with an existing national standard charging basic framework, can realize common progress with domestic technology, reduces the influence of variable OBC on the vehicle framework, and realizes product development generalization.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new energy vehicle charging technology, and particularly relates to a new energy commercial vehicle slow charging system and a slow charging method thereof. BACKGROUND

[0002] New energy vehicle charging is a key technology for new energy vehicles. The national standard charging technology has become standardized, and most of the technical routes are BMS charging management, and some charging management functions are integrated in the VCU controller. With the development of new energy vehicles, the export business of new energy vehicles has gradually developed. In view of the fact that the international market generally uses CC2 (CC1) charging standards, which is quite different from the national standard slow charging, the development of European (American) standard slow charging has become a new demand.

[0003] Therefore, a new energy commercial vehicle slow charging system and a slow charging method thereof are urgently needed. SUMMARY

[0004] The present application aims to provide a new energy commercial vehicle slow charging system and a slow charging method thereof to solve the problems in the prior art, and to design a charging strategy for realizing European and American standard charging functions based on the existing national standard charging framework.

[0005] The present application provides a new energy commercial vehicle slow charging system, comprising:

[0006] a vehicle-mounted charger, a vehicle control unit, a battery management system, a multi-in-one control box, a conversion controller and a European and American standard charging pile, wherein:

[0007] The vehicle control unit, the battery management system, the vehicle-mounted charger and the multi-in-one control box are connected to the vehicle EVCAN network.

[0008] The battery management system communicates with the conversion controller through a national standard charging CAN network.

[0009] The conversion controller interacts with the European and American standard charging pile through a CP carrier signal.

[0010] The European and American standard charging gun of the European and American standard charging pile is connected to the vehicle-mounted charger, and the vehicle-mounted charger is further connected to the multi-in-one control box.

[0011] The new energy commercial vehicle slow charging system as described above, wherein, preferably, the multi-in-one control box is integrated with a vehicle relay, a slow charging relay and a fuse box, and the vehicle relay comprises a total positive pre-charging circuit, a main positive pre-charging circuit, a negative relay, an auxiliary drive pre-charging circuit and an auxiliary drive pre-charging circuit.

[0012] The new energy commercial vehicle slow charging system as described above, preferably, the AC power of the Europlug charging gun of the Europlug charging pile is connected to the high-voltage input interface of the on-board charger through a wire, the on-board charger is provided with a DC output, and the slow charging interface of the all-in-one control box is connected to the DC output through a wire.

[0013] The application also provides a slow charging method using the above system, comprising:

[0014] The charging is started, the vehicle controller is activated by the battery management system, the battery management system and the conversion controller are charged, and the battery management system and the battery management system are charged;

[0015] After the vehicle controller is activated, the MC low-voltage relay is closed, the all-in-one control box, the motor controller and the battery management system are activated through the MC low-voltage relay, and the battery management system is instructed to charge;

[0016] After the battery management system completes the interaction information with the conversion controller, the slow charging relay of the all-in-one control box is closed in response to the charging instruction issued by the vehicle controller;

[0017] After the battery management system completes the interaction information with the Europlug charging pile through the conversion controller, the AC power of the Europlug charging pile is input to the input end of the on-board charger, and the on-board charger outputs DC power to the all-in-one control box according to the charging mode requested by the battery management system to charge the battery, the charging mode including constant current charging or constant voltage charging.

[0018] The slow charging method as described above, preferably, in the charging start, the vehicle controller is activated by the battery management system, the battery management system and the conversion controller are charged, and the battery management system and the battery management system are charged, specifically comprising:

[0019] The battery management system starts initialization after identifying the confirmation signal that the gun is connected to the PP port;

[0020] After the battery management system completes initialization, an activation signal is output to activate the vehicle controller through the vehicle EVCAN network;

[0021] The battery management system charges the conversion controller through CAN communication messages, the conversion controller transmits the Europlug pile charging information to the battery management system, and the conversion controller transmits the vehicle end charging information to the Europlug charging pile.

[0022] The slow charging method as described above, wherein preferably, after the vehicle controller is activated, the MC low-voltage relay is controlled to be closed, and the all-in-one control box, the motor controller and the battery management system are activated through the MC low-voltage relay, and the battery management system is instructed to charge, specifically including:

[0023] After the vehicle controller is activated, self-checking is performed;

[0024] After the vehicle controller passes the self-checking, the MC low-voltage relay is controlled to be closed;

[0025] After the MC low-voltage relay is closed, the all-in-one control box, the motor controller and the battery management system are activated;

[0026] If the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller sends a main negative relay closing instruction through the vehicle EVCAN network, and after the all-in-one control box receives the main negative relay closing instruction, a main pre-charging relay instruction is sent to close the main positive relay;

[0027] If the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller sends a main negative relay closing instruction through the vehicle EVCAN network, and after the all-in-one control box receives the main negative relay closing instruction, a main pre-charging relay instruction is sent to close the main positive relay;

[0028] If the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller sends a main negative relay closing instruction through the vehicle EVCAN network, and after the all-in-one control box receives the main negative relay closing instruction, a main pre-charging relay instruction is sent to close the main positive relay;

[0029] The vehicle controller sends an instruction to allow the battery management system to charge.

[0030] The slow charging method as described above, wherein preferably, after the vehicle controller is activated, the MC low-voltage relay is controlled to be closed, and the all-in-one control box, the motor controller and the battery management system are activated through the MC low-voltage relay, and the battery management system is instructed to charge, specifically including:

[0031] After the battery management system completes the interaction information with the conversion controller, it sends a request for charging instruction to the vehicle controller through the vehicle EVCAN network and waits;

[0032] After receiving the instruction to allow charging sent by the vehicle controller, the battery management system sends a slow-charging charging relay closing instruction to the all-in-one control box;

[0033] After receiving the slow-charging charging relay closing instruction, the all-in-one control box controls the slow-charging relay to be closed;

[0034] The all-in-one control box reports the slow-charging relay state to the vehicle EVCAN network.

[0035] The slow charging method as described above, wherein preferably, after the battery management system completes the interaction with the European standard charging pile through the conversion controller, the alternating current of the European standard charging pile is input to the input end of the on-board charger, and the on-board charger outputs direct current to the multi-functional control box according to the charging mode requested by the battery management system to charge the battery, specifically comprising:

[0036] After the battery management system completes the interaction with the European standard charging pile through the conversion controller, the alternating current of the European standard charging pile is input to the input end of the on-board charger;

[0037] After the on-board charger detects the AC point voltage, the on-board charger is activated;

[0038] After the on-board charger is activated, the battery management system synchronously receives the requested charging voltage or the requested charging current, and outputs constant-current direct current or constant-voltage direct current to the slow charging interface of the multi-functional control box according to the set voltage value or the set current value to charge the battery.

[0039] The slow charging method as described above, wherein preferably, the slow charging method further comprises: during the slow charging process, according to the monitoring results of the vehicle controller, the battery management system and the on-board charger, interrupting the slow charging process, specifically comprising:

[0040] During the slow charging process, the multi-functional control box enables the DCDC converter to continuously charge the battery; the vehicle controller continuously monitors whether there is a fault mode affecting slow charging at the vehicle end, and if so, the charging permission signal is converted into a charging disallowed signal, and the battery management system cuts off the slow charging after receiving the charging disallowed message;

[0041] During the slow charging process, the battery management system continuously monitors whether there is a fault mode affecting slow charging in the battery system, and if so, the charging is cut off and the request charging signal is disconnected, and the vehicle controller cannot continuously receive the request charging signal within a set time, then the multi-functional control box is controlled to power off the vehicle under high voltage;

[0042] During the slow charging process, the on-board charger continuously monitors whether there is a fault affecting the slow charging function of the charger, and if so, the fault code is reported, and the battery management system reads the preset fault code and then executes the charging disconnection process.

[0043] The slow charging method as described above, wherein preferably, the slow charging method further comprises: switching the charging mode of the battery according to the minimum temperature of the battery, specifically comprising:

[0044] If the minimum battery temperature is less than or equal to 0 DEG C, the battery management system sends a constant voltage charging request, and the voltage requirement is the battery pack voltage, at this time, the European and American standard charging pile only powers the battery heating film to heat the battery;

[0045] If the minimum battery temperature is greater than or equal to 1 DEG C, the battery management system sends a constant current charging request, and the constant voltage charging mode is converted to the constant current charging mode until the battery is fully charged.

[0046] The new energy commercial vehicle slow charging system and the slow charging method thereof provided by the application combine the existing national standard charging basic framework, design a charging strategy for realizing the European and American standard charging function, and design a slow charging control strategy jointly participated by a vehicle controller, a battery management system, a conversion controller, a multi-in-one control box, a vehicle-mounted charger and the like; the interaction function of the vehicle-mounted charger is simplified, the plug-in gun confirmation, the opening and closing of the electronic lock, and the CP vehicle pile interaction function are transferred to other controllers, the vehicle high-voltage power distribution function management is performed through the vehicle controller, the battery management system and the conversion controller are physically integrated or designed in a distributed manner, the national standard charging function framework design can be maintained, only the control logic of the vehicle-mounted charger is added, the European and American standard charging function can be realized, which is helpful for the promotion of the exported battery vehicle, the existing vehicle model platform framework structure design is not changed, the design is simplified, the common development of the product can be realized, the influence of the change of the vehicle-mounted charger on the vehicle framework is reduced, and the product development is universalized. BRIEF DESCRIPTION OF DRAWINGS

[0047] To make the objectives, technical solutions and advantages of the application clearer, the following further describes the application with reference to the accompanying drawings, in which:

[0048] Figure 1 The figure shows the architecture of the new energy commercial vehicle slow charging system provided by the application;

[0049] Figure 2 The figure shows the flowchart of the slow charging method provided by the application. DETAILED DESCRIPTION

[0050] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative in nature and is in no way limiting, as to the disclosure and its applications or uses. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that the present disclosure is thorough and complete and fully conveys the scope of the present disclosure to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions and values set forth in these embodiments should be interpreted as merely exemplary, rather than as a limitation.

[0051] The terms "first", "second", and similar terms used in the present disclosure do not denote any order, quantity, or importance, but are used to distinguish different parts. The terms "include", "contain", and similar terms mean that the elements before the terms encompass the elements listed after the terms, and do not exclude the possibility of also encompassing other elements. "Up", "down", and the like are used only to indicate relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship can also change accordingly.

[0052] In the present disclosure, when it is described that a specific component is located between a first component and a second component, there can be an intervening component between the specific component and the first component or the second component, or there can be no intervening component. When it is described that a specific component is connected to other components, the specific component can be directly connected to the other components without an intervening component, or can not be directly connected to the other components with an intervening component.

[0053] All terms used in the present disclosure, including technical terms or scientific terms, have the same meaning as understood by a person of ordinary skill in the art to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary should be interpreted in a manner consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or excessively formalized sense, unless specifically defined herein.

[0054] Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered part of the specification where appropriate.

[0055] As shown in Figure 1 The new energy commercial vehicle slow charging system provided by the embodiment includes an on-board charger (OBC), a vehicle control unit (VCU), a battery management system (BMS), a multi-in-one control box (PDU), a conversion controller (EVCC), and a European and American standard charging pile, wherein:

[0056] The vehicle control unit, the battery management system, the on-board charger, and the multi-in-one control box are connected to a vehicle EVCAN network;

[0057] The battery management system communicates with the conversion controller through a national standard charging CAN network;

[0058] The conversion controller interacts with the European and American standard charging pile through a CP carrier signal;

[0059] The European and American standard charging gun of the European and American standard charging pile is connected to the on-board charger, and the on-board charger is also connected to the multi-in-one control box.

[0060] The multi-in-one control box is integrated with a whole vehicle relay, a slow charging relay and a fuse box, and the whole vehicle relay includes a total positive pre-charging circuit, a main positive pre-charging circuit, a negative relay, an auxiliary drive pre-charging circuit and an auxiliary drive pre-charging circuit.

[0061] Further, the whole vehicle controller, the battery management system, the on-board charger and the multi-in-one control box communicate with the whole vehicle EVCAN network by using SAE J1939 standard frame format messages. The interaction information between the conversion controller and the European standard charging pile includes vehicle information and charging pile information.

[0062] Further, the AC power of the European standard charging gun of the European standard charging pile is connected to the high-voltage input interface of the on-board charger through a wire cable, and the on-board charger is provided with a DC output connected to the slow charging interface of the multi-in-one control box.

[0063] Specifically, as shown in Figure 2 The slow charging method provided by the embodiment specifically includes the following steps in the actual execution process:

[0064] Step S1, charging start, activating the whole vehicle controller by the battery management system, and the battery management system and the conversion controller perform charging interaction, and the battery management system and the battery management system perform charging interaction.

[0065] In an embodiment of the slow charging method of the application, the step S1 specifically can include:

[0066] Step S11, the battery management system starts initialization after identifying the confirmation signal that the gun is connected to the PP port.

[0067] Step S12, after the battery management system initialization is completed, an activation signal is output, and the whole vehicle controller is activated through the whole vehicle EVCAN network.

[0068] Step S13, the battery management system uses CAN communication messages to perform charging interaction with the conversion controller, the conversion controller transmits European standard pile charging information to the battery management system, and the conversion controller transmits vehicle end charging information to the European standard charging pile.

[0069] Wherein, the interaction process between the battery management system and the conversion controller refers to GBT 27930, which will not be repeated here. Illustratively, the conversion controller can transmit European standard pile charging capacity information to the battery management system, and the battery management system transmits vehicle end battery parameters and vehicle end charging preparation conditions to the European standard charging pile.

[0070] When the charging is started, the battery management system first identifies the plug-in gun PP connection confirmation signal, and after initialization, an active electrical signal is output to activate the vehicle controller through a hard line; the battery management system uses CAN communication messages to interact with the conversion controller for charging, and the conversion controller transmits the charging capacity information of the European and American standard pile to the BMS, and transmits the battery parameters and charging preparation conditions of the vehicle end to the European and American standard charging pile.

[0071] Step S2, after the vehicle controller is activated, the MC low-voltage relay is closed, and the multi-function control box, the motor controller and the battery management system are activated through the MC low-voltage relay, and the battery management system is instructed to charge.

[0072] In an embodiment of the slow charging method of the application, step S2 can specifically include:

[0073] Step S21, after the vehicle controller is activated, self-checking is performed.

[0074] Step S22, after the vehicle controller is self-checked and qualified, the MC low-voltage relay is controlled to be closed.

[0075] Step S23, after the MC low-voltage relay is closed, the multi-function control box, the motor controller and the battery management system are activated.

[0076] Step S24, if the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller issues a main negative relay closing instruction through the vehicle EV CAN network, and after the multi-function control box receives the main negative relay closing instruction, a main pre-charging relay instruction is issued to close the main positive relay.

[0077] Step S25, if the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller issues a main negative relay closing instruction through the vehicle EV CAN network, and after the multi-function control box receives the main negative relay closing instruction, an auxiliary pre-charging relay instruction is issued to close the auxiliary pre-charging relay.

[0078] Step S26, if the vehicle controller has no high-voltage prohibition fault mode, the vehicle controller issues a main negative relay closing instruction through the vehicle EV CAN network, and after the multi-function control box receives the main negative relay closing instruction, an auxiliary pre-charging relay instruction is issued to close the auxiliary pre-charging relay.

[0079] Step S27, the vehicle controller issues an instruction to allow the battery management system to charge.

[0080] After the whole vehicle controller is activated, self-checking is performed first, then the MC low-voltage relay is controlled to be closed, the activation electrical signal of the multi-in-one control box, the motor controller, the battery management system and the like under the MC low-voltage relay is activated, the activation of the main controller of the whole vehicle is realized, there is no inhibit high-voltage fault mode, the main negative relay closing instruction is issued, after the main negative relay closing instruction is received, the main pre-charging relay instruction is issued, the main positive relay is closed, and the auxiliary pre-charging relay and the auxiliary loop positive relay are closed in the same way; after the above actions are completed, the battery management system charging permission instruction is issued.

[0081] In step S3, after the battery management system completes the interaction information with the conversion controller, the multi-in-one control box is controlled to close the slow charging relay in response to the charging permission instruction issued by the whole vehicle controller.

[0082] In an embodiment of the slow charging method of the application, step S3 can specifically include:

[0083] In step S31, after the battery management system completes the interaction information with the conversion controller, a request charging instruction is sent to the whole vehicle controller through the whole vehicle EV CAN network, and waiting is performed.

[0084] In step S32, after the charging permission instruction issued by the whole vehicle controller is received, the battery management system issues a slow charging relay closing instruction to the multi-in-one control box.

[0085] In step S33, after the slow charging relay closing instruction is received by the multi-in-one control box, the slow charging relay is controlled to be closed.

[0086] In step S34, the multi-in-one control box reports the slow charging relay state to the whole vehicle EV CAN network.

[0087] After the battery management system completes the interaction information with the conversion controller, a request charging instruction is sent, waiting is performed, after the charging permission instruction issued by the whole vehicle controller is received, a slow charging relay closing instruction is issued to the multi-in-one control box, and the multi-in-one control box closes the slow charging relay and reports the slow charging relay state after receiving the instruction.

[0088] In step S4, after the battery management system completes the interaction information with the European and American standard charging pile through the conversion controller, the alternating current of the European and American standard charging pile is input to the input end of the on-board charger, and the on-board charger outputs direct current to the multi-in-one control box according to the charging mode requested by the battery management system, so as to charge the battery, and the charging mode includes constant current charging or constant voltage charging.

[0089] In an embodiment of the slow charging method of the application, step S4 can specifically include:

[0090] Step S41, after the battery management system completes the interaction with the Europe and America standard charging pile through the conversion controller, AC power of the Europe and America standard charging pile is input to an input end of the on-board charger.

[0091] Step S42, after the on-board charger detects the AC point voltage, the on-board charger is activated.

[0092] Step S43, after the on-board charger is activated, the requested charging voltage or the requested charging current sent by the battery management system is synchronously received, and constant-current direct current or constant-voltage direct current is output to a slow charging interface of the all-in-one control box according to the set voltage value or the set current value, so as to charge the battery.

[0093] After the battery management system completes the interaction with the Europe and America charging pile, AC power of the Europe and America charging pile is input to an input end of the on-board charger, the on-board charger is activated after detecting the AC point voltage, and the on-board charger synchronously receives the requested charging voltage and current sent by the battery management system, and outputs DC power to the slow charging interface of the all-in-one control box according to the set voltage and current value, so as to charge the battery.

[0094] Further, in some embodiments of the present application, the slow charging method further comprises:

[0095] Step S5, during the slow charging process, the slow charging process is interrupted according to the monitoring results of the vehicle controller, the battery management system and the on-board charger.

[0096] In one embodiment of the slow charging method of the present application, the step S5 can specifically comprise:

[0097] Step S51, during the slow charging process, the all-in-one control box enables the DCDC converter (also referred to as a direct current voltage converter) to continuously charge the battery; the vehicle controller continuously monitors whether there is a fault mode affecting slow charging at the vehicle end, and if there is, the charging permission signal is converted into a charging disallowed signal, and the battery management system cuts off the slow charging after receiving the charging disallowed message.

[0098] Step S52, during the slow charging process, the battery management system continuously monitors whether there is a fault mode affecting slow charging in the battery system, and if there is, the charging is cut off and the requested charging signal is sent, and the vehicle controller cannot continuously receive the requested charging signal within a set time, and controls the all-in-one control box to power off under high voltage of the vehicle.

[0099] For example, the fault mode affecting slow charging in the battery system is total voltage abnormality, single body voltage abnormality, temperature abnormality, etc.

[0100] Step S53, during the slow charging process, the on-board charger continuously monitors whether the charger has a fault affecting the slow charging function, and if so, the fault code is reported. After the battery management system reads the preset fault code, the charging process is disconnected.

[0101] Further, in some embodiments, the slow charging method further comprises:

[0102] Step S6, switching the charging mode of the battery according to the minimum temperature of the battery.

[0103] In one embodiment of the slow charging method of the present application, the step S6 can specifically include:

[0104] Step S61, if the minimum temperature of the battery is less than or equal to 0℃, the battery management system sends a constant voltage charging request, and the voltage demand is the battery pack voltage. At this time, the European and American standard charging pile only powers the battery heating film to heat the battery.

[0105] Step S62, if the minimum temperature of the battery is greater than or equal to 1℃, the battery management system sends a constant current charging request, and the constant voltage charging mode is converted to a constant current charging mode until the battery is fully charged.

[0106] The new energy commercial vehicle slow charging system and the slow charging method thereof provided by the embodiment of the present application combine the existing national standard charging basic framework, design a charging strategy for realizing the European and American standard charging function, and design a slow charging control strategy jointly participated by the vehicle controller, the battery management system, the conversion controller, the multi-in-one control box, the on-board charger and other controllers. The interaction function of the on-board charger is simplified, the plug-in gun confirmation, the opening and closing of the electronic lock, and the CP vehicle pile interaction function are transferred to other controllers, the high voltage power distribution function management of the whole vehicle is performed through the vehicle controller, the battery management system and the conversion controller are physically integrated or designed in a distributed manner, the national standard charging function framework design can be maintained, only the control logic of the on-board charger is increased, the European and American standard charging function can be realized, which is helpful for the promotion of export battery vehicles, the existing vehicle platform framework structure design is not changed, the design is simplified, the common progress with domestic technology can be realized, the influence of the changed on-board charger on the vehicle framework is reduced, and the product development generalization is realized.

[0107] So far, the embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein according to the above description.

[0108] Although some specific embodiments of the present disclosure have been described in detail by way of example with reference to the drawings, it is to be understood that the above examples are intended to be illustrative only and are not intended to limit the scope of the present disclosure. It is to be understood that modifications or equivalent arrangements of the above embodiments can be made by those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A new energy commercial vehicle slow charging system, characterized in that, The application relates to a vehicle-mounted charger, a vehicle controller, a battery management system, a multi-in-one control box, a conversion controller and a European and American standard charging pile, wherein the vehicle controller, the battery management system, the vehicle-mounted charger and the multi-in-one control box are connected to a vehicle EVCAN network; the battery management system communicates with the conversion controller through a national standard charging CAN network; the conversion controller communicates with the European and American standard charging pile through a CP carrier signal; a European and American standard charging gun of the European and American standard charging pile is connected with the vehicle-mounted charger, and the vehicle-mounted charger is further connected with the multi-in-one control box; the battery management system is used for activating the vehicle controller after charging is started, and the battery management system communicates with the conversion controller, the battery management system communicates with the battery management system, and the battery management system is specifically used for: starting initialization after a confirmation signal that a charging gun is connected to a PP port is recognized; outputting an activation electrical signal to activate the vehicle controller through the vehicle EVCAN network after initialization is completed; and communicating with the conversion controller through a CAN communication message, wherein the conversion controller transmits European and American standard pile charging information to the battery management system, and the conversion controller transmits vehicle end charging information to the European and American standard charging pile; the vehicle controller is used for controlling an MC low-voltage relay to be closed after being activated, and activating the multi-in-one control box, a motor controller and the battery management system through the MC low-voltage relay, and issuing a charging instruction to allow the battery management system to charge; the battery management system is further used for controlling the multi-in-one control box to close a slow charging relay in response to the charging instruction issued by the vehicle controller after interaction information with the conversion controller is completed; the battery management system is further used for inputting alternating current of the European and American standard charging pile to an input end of the vehicle-mounted charger after interaction information with the European and American standard charging pile through the conversion controller is completed, and outputting direct current to the multi-in-one control box according to a charging mode requested by the battery management system, so as to charge the battery, wherein the charging mode includes constant current charging or constant voltage charging; if the lowest temperature of the battery is less than or equal to 0 DEG C, the battery management system sends a constant voltage charging request, and the voltage demand is the voltage of the battery pack, at this moment, the European and American standard charging pile only supplies power to a battery heating film to heat the battery; if the lowest temperature of the battery is greater than or equal to 1 DEG C, the battery management system sends a constant current charging request, and the constant voltage charging mode is converted into the constant current charging mode until the battery is fully charged. The multi-in-one control box is internally integrated with a vehicle relay, a slow charging relay and an insurance box, and the vehicle relay includes a total positive pre-charging circuit, a main positive pre-charging circuit, a negative relay, an auxiliary drive pre-charging circuit and an auxiliary drive pre-charging circuit. Alternating current of the European and American standard charging gun of the European and American standard charging pile is connected to a high-voltage input interface of the vehicle-mounted charger through a cable, and the vehicle-mounted charger is provided with a direct current output and is connected to a slow charging interface of the multi-in-one control box through a cable. The application further relates to a charging method, and the method comprises the following steps: charging is started, the vehicle controller is activated through the battery management system, and the battery management system communicates with the conversion controller, and the battery management system communicates with the battery management system; ​ ​ ​ ​ ​ 2. The new energy commercial vehicle slow charging system according to claim 1, characterized in that, ​ 3. The new energy commercial vehicle slow charging system according to claim 1, characterized in that, ​ 4. A slow charging method using the system according to any one of claims 1 to 3, characterized in that, ​ ​ The whole vehicle controller is activated, the MC low voltage relay is controlled to be closed, the multi-in-one control box, the motor controller and the battery management system are activated through the MC low voltage relay, and the battery management system is instructed to charge; After the battery management system completes the interaction information with the conversion controller, the multi-in-one control box is controlled to close the slow charging relay in response to the charging instruction issued by the whole vehicle controller; After the battery management system completes the interaction information with the conversion controller, the AC input of the European and American standard charging pile is input to the input end of the on-board charger, and the on-board charger outputs DC to the multi-in-one control box according to the charging mode requested by the battery management system, so as to charge the battery, and the charging mode includes constant current charging or constant voltage charging, In the charging start, the battery management system activates the whole vehicle controller, and the battery management system and the battery management system perform charging interaction, specifically including: The battery management system identifies the confirmation signal that the plug is connected to the PP port, and starts initialization; After the battery management system completes the initialization, an activation signal is output to activate the whole vehicle controller through the whole vehicle EVCAN network; The battery management system performs charging interaction with the conversion controller by using CAN communication messages, the conversion controller transmits European and American standard pile charging information to the battery management system, and the conversion controller transmits vehicle end charging information to the European and American standard charging pile.

5. The slow charging method according to claim 4, characterized in that, After the whole vehicle controller is activated, the MC low voltage relay is controlled to be closed, the multi-in-one control box, the motor controller and the battery management system are activated through the MC low voltage relay, and the battery management system is instructed to charge; After the whole vehicle controller is activated, self-checking is performed; After the whole vehicle controller is activated, self-checking is performed; After the whole vehicle controller is activated, self-checking is performed; If the whole vehicle controller has no high voltage prohibition fault mode, the whole vehicle controller issues a main negative relay closing instruction through the whole vehicle EVCAN network, the multi-in-one control box receives the main negative relay closing instruction, and issues a main pre-charging relay instruction to close the main positive relay; If the whole vehicle controller has no high voltage prohibition fault mode, the whole vehicle controller issues a main negative relay closing instruction through the whole vehicle EVCAN network, the multi-in-one control box receives the main negative relay closing instruction, and issues a main pre-charging relay instruction to close the main positive relay; If the whole vehicle controller has no high voltage prohibition fault mode, the whole vehicle controller issues a main negative relay closing instruction through the whole vehicle EVCAN network, the multi-in-one control box receives the main negative relay closing instruction, and issues a main pre-charging relay instruction to close the main positive relay; The whole vehicle controller issues an instruction to allow the battery management system to charge.

6. The slow charging method of claim 4, wherein, After the battery management system completes the interaction information with the conversion controller, the multi-in-one control box is controlled to close the slow charging relay in response to the charging instruction issued by the whole vehicle controller, specifically including: After the battery management system completes the interaction information with the conversion controller, the battery management system sends a request charging instruction to the whole vehicle controller through the whole vehicle EVCAN network, and waits; After receiving the slow charging relay closing instruction issued by the whole vehicle controller, the battery management system issues the slow charging relay closing instruction to the all-in-one control box; After receiving the slow charging relay closing instruction, the all-in-one control box controls the slow charging relay to close; The all-in-one control box reports the slow charging relay state to the whole vehicle CAN network.

7. The slow charging method of claim 4, wherein, After the battery management system completes the interaction with the European and American standard charging pile through the conversion controller, the alternating current of the European and American standard charging pile is input to the input end of the on-board charger, and the on-board charger outputs direct current to the all-in-one control box according to the charging mode requested by the battery management system to charge the battery, specifically including: After the battery management system completes the interaction with the European and American standard charging pile through the conversion controller, the alternating current of the European and American standard charging pile is input to the input end of the on-board charger; After detecting the AC point voltage, the on-board charger is activated; After activation, the on-board charger synchronously receives the request charging voltage or request charging current sent by the battery management system, and outputs constant current direct current or constant voltage direct current to the slow charging interface of the all-in-one control box according to the set voltage value or set current value to charge the battery.

8. The slow charging method of claim 4, wherein, The slow charging method further includes: during the slow charging process, according to the monitoring results of the whole vehicle controller, the battery management system and the on-board charger, interrupting the slow charging process, specifically including: During the slow charging process, the all-in-one control box enables the DCDC converter to continuously charge the battery; the whole vehicle controller continuously monitors whether there is a fault mode affecting slow charging at the whole vehicle end, if there is, the charging permission signal is converted into a charging disallowed signal, and the battery management system cuts off the slow charging after receiving the charging disallowed message; During the slow charging process, the battery management system continuously monitors whether there is a fault mode affecting slow charging in the battery system, if there is, the charging is cut off, and the request charging signal is sent; if the whole vehicle controller cannot continuously receive the request charging signal within a set time, the all-in-one control box is controlled to power off the whole vehicle under high voltage; During the slow charging process, the on-board charger continuously monitors whether there is a fault affecting the slow charging function of the charger, if there is, the fault code is reported, and the battery management system reads the preset fault code and then executes the charging disconnection process.

9. The slow charging method of claim 4, wherein, The slow charging method further includes: switching the charging mode of the battery according to the minimum temperature of the battery, specifically including: If the minimum temperature of the battery is less than or equal to 0℃, the battery management system sends a constant voltage charging request, and the voltage demand is the battery pack voltage, at this time the European and American standard charging pile only supplies power to the battery heating film to heat the battery; If the minimum temperature of the battery is greater than or equal to 1℃, the battery management system sends a constant current charging request, and the constant voltage charging mode is converted to a constant current charging mode until the battery is fully charged.

Images