Communication method and system based on electric locomotive battery management system

Abstract

The invention belongs to the field of battery state information communication, and particularly relates to a communication method and system based on an electric locomotive battery management system. Comprising the following steps: in each interrogation period, according to a first time interval, respectively interrogating first battery information of battery clusters in one-to-one correspondence to each master control module of the battery management system in sequence; the first time interval is greater than or equal to the longest time of sending the first battery information by the single main control module; each master control module respectively takes a second time interval and a third time interval as cycles to upload second battery information and third battery information of the battery clusters in one-to-one correspondence with the master control module; the first and second time intervals are smaller than the third time interval; the first battery information is battery information required by real-time control of the whole vehicle and used for power-on, power-off, charging or discharging control; the second battery information is battery information required by real-time control of the whole vehicle and used for fault positioning and diagnosis; the third battery information is battery information which is not needed by real-time control of the whole vehicle.

Description

Technical Field

[0001] The present invention belongs to the field of battery status information communication, and in particular relates to a communication method and system based on an electric locomotive battery management system. Background Art

[0002] In electric locomotives, BMS (i.e., battery management system) exchanges data in real time with on-board chargers, motor controllers and other devices through the CAN bus (i.e., master CAN communication). The exchanged data includes information such as SOC (state of charge), SOH (state of health), current, total voltage, insulation, battery extreme value data, power-off request messages, and fault codes. Master CAN communication is the mainstream communication method for transmitting battery status information. Based on the battery management system of electric locomotives, the use of master CAN communication can achieve efficient collaboration between BMS, chargers and motor controllers, and support real-time status monitoring and dynamic adjustment of charging strategies.

[0003] However, with the rapid development of the electric locomotive industry, corresponding monitoring requirements have been generated for a wide variety of parameters (that is, each battery node needs to transmit voltage, current, temperature, SOC, SOH and other parameters for monitoring), and the parameter transmission requirements of the main control CAN communication have increased dramatically; and the size of the battery pack installed in the electric locomotive is also growing, resulting in an increase in the number of nodes, which in turn intensifies bus competition, reduces arbitration efficiency, and increases the bus load rate. Assuming there are 20 battery nodes, each node sends 10 data frames per second, the frame length is 100 bits, and the baud rate is 500kbps, the load rate is 40%. In addition, in some scenarios (such as fast charging scenarios), the data transmission frequency needs to be increased, which will further increase the total load rate.

[0004] In summary, in order to meet the growing industry demands for parameter transmission, battery nodes, and data transmission frequency, a large amount of data is often transmitted during communication, which increases the communication burden of the main control CAN communication, resulting in the vehicle CAN bus load rate usually being greater than 30%. Not only will the real-time performance of communication be affected, but it will also be difficult to ensure the quality and reliability of communication. Summary of the invention

[0005] The purpose of the present invention is to provide a communication method and system based on an electric locomotive battery management system, which is used to solve the problem in the prior art that the amount of data transmitted during the main control CAN communication is too large, which seriously increases the communication load rate and thus affects the real-time performance, quality and reliability of the communication.

[0006] To achieve the above object, the present invention provides a communication method based on a battery management system of an electric locomotive, the method comprising: within each polling period, at a first time interval, successively polling the first battery information of each battery cluster corresponding to each main control module of the battery management system; the first time interval being greater than or equal to the longest time for a single main control module to send the first battery information; Further comprising: each main control module respectively sending the second and third battery information of the battery cluster corresponding to it at the second and third time intervals; the first and second time intervals being both less than the third time interval; The first battery information is the battery information required for real-time control of the whole vehicle for power-on, power-off, charging or discharging control; the second battery information is the battery information required for real-time control of the whole vehicle for fault location and diagnosis; the third battery information is the battery information not required for real-time control of the whole vehicle.

[0007] Beneficial effects: The present invention provides a new communication method based on a battery management system of an electric locomotive. The method polls each main control module in the battery management system to successively poll (i.e., the real-time control module of the whole vehicle successively sends polling instructions to each main control module, and after each main control module receives the polling instruction, it sends the first battery information collected by it to the real-time control system of the whole vehicle in a discrete process) the first battery information of each battery cluster corresponding to each main control module within each polling period, and the time interval for polling this information is the first time interval. The first battery information is the battery information required for real-time control of the whole vehicle for power-on, power-off, charging or discharging control, that is, this type of battery information is necessary information for realizing real-time control of the whole vehicle, and such information needs to be judged in real time, so the first time interval is a relatively small time interval. And since it takes time for a single main control module to send its corresponding first battery information, the first time interval needs to be greater than or equal to the longest time for a single main control module to send the first battery information to ensure the integrity of the information sent by a single main control module, thereby realizing real-time control of the whole vehicle. In addition to the first battery information, there are also the second and third battery information; the second battery information is the battery information required for real-time control of the whole vehicle for fault location and diagnosis. This second battery information is also related to real-time control of the whole vehicle, so it also has real-time performance, so the second battery information is also sent at a relatively small time interval (i.e., the second time interval). And the above-mentioned third battery information represents the battery information not required for real-time control of the whole vehicle; this type of battery information only reflects the battery state in different forms and does not participate in real-time control of the whole vehicle and does not need to have real-time performance; therefore, the time interval (i.e., the third time interval) for each main control module to send the third battery information is a relatively long time interval compared with the first and second time intervals.

[0008] In summary, the method first polls each main control module to call and measure the first battery information, which can ensure that only the currently polled main control module sends data within the same time period, and there is no situation where multiple main control modules send a large amount of data simultaneously. Thus, communication conflicts caused by simultaneous data transmission are avoided, thereby reducing communication pressure. In addition, the method uses a combination of short cycles and long cycles to realize the upload of necessary data related to fault judgment, so as to achieve short-cycle communication for data that participates in real-time vehicle control and is necessary for fault judgment and needs to be actively uploaded to ensure the real-time nature and timeliness of such data; for battery information that is not required for real-time vehicle control, long-cycle communication is carried out, thereby reducing unnecessary redundant data transmission.

[0009] Further, the second time interval is equal to the first time interval; or, the second time interval is less than the first time interval and the first time interval is an integer multiple of the second time interval.

[0010] Further, the method of sequentially sending call and measurement instructions to each main control module of the battery management system at the first time interval within each call and measurement cycle includes: within each call and measurement cycle, through the vehicle controller, sequentially sending call and measurement instructions to each main control module of the battery management system at the first time interval.

[0011] Further, the first battery information includes: the SOC of each single battery in the battery cluster, the SOH of each single battery in the battery cluster, the current of each single battery in the battery cluster, the total voltage of the battery cluster, insulation data, the extreme value data of each single battery in the battery cluster, and the power-off request message.

[0012] Further, the second battery information includes: battery system status data and contactor status data; the battery system status data includes data corresponding to the current state of the battery cluster; the current state of the battery cluster includes a charging state, a discharging state, a standby state, and a fault state.

[0013] Further, the third battery information includes at least one of the cumulative charge and discharge amounts of the battery cluster, battery boundary data, and single battery information; The battery boundary data includes the upper and lower limit values of the voltage of the single battery, and the upper and lower limit values of the temperature of the single battery; the single battery information includes the voltage and temperature of each single battery in the battery cluster.

[0014] Further, the lower limit value of the value range of the first time interval is 50 ms; the upper limit value of the value range of the first time interval is 200 ms.

[0015] Further, the lower limit value of the value range of the second time interval is 50 ms; the upper limit value of the value range of the second time interval is 100 ms.

[0016] Furthermore, the lower limit value of the range of the third time interval is 1 s; the upper limit value of the range of the third time interval is 60 s.

[0017] The present invention also provides a communication system based on an electric locomotive battery management system, including a processor for executing a computer program to implement the steps of the above-mentioned communication method based on the electric locomotive battery management system.

[0018] The communication system based on the electric locomotive battery management system can achieve the same beneficial effects as the above-mentioned communication method based on the electric locomotive battery management system. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the master-slave control architecture of the electric locomotive battery management system in the embodiment of the communication method based on the electric locomotive battery management system of the present invention; Figure 2 It is a communication message table for communicating by using the communication method based on the electric locomotive battery management system in the embodiment of the communication method based on the electric locomotive battery management system of the present invention. Detailed Embodiments

[0020] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments.

[0021] Embodiment of the Communication Method Based on the Electric Locomotive Battery Management System This embodiment provides a technical solution of a communication method based on an electric locomotive battery management system. This method polls and measures the battery information required for real-time vehicle control sent by each main control module of the battery management system at a relatively short time interval, controls each main control module to actively send the battery information for fault judgment required for real-time vehicle control at another relatively short time interval, and controls each main control module to actively send the battery information for fault judgment that is not required for real-time vehicle control at a relatively long time interval. That is, by using this method of periodic polling and combined uploading of long and short periods to upload battery information, it is possible to reduce the communication pressure on the basis of timely providing the battery information required for vehicle control.

[0022] It includes: within each polling cycle, polling and measuring the first battery information of each battery cluster corresponding to each main control module of the battery management system in sequence at the first time interval. When setting the first time interval, the setting condition of the first time interval needs to be met: the first time interval is greater than or equal to the longest time for a single main control module to send the first battery information. On the basis of meeting this condition, the range of the first time interval is limited: the lower limit value of the range of the first time interval is 50 ms; the upper limit value is 200 ms.

[0023] In this embodiment, the method of polling the first battery information of each battery cluster corresponding to each main control module of the battery management system in sequence at the first time interval within each polling period is as follows: within each polling period, the vehicle controller sequentially sends polling instructions to each main control module of the battery management system at the first time interval.

[0024] Reference Figure 1 , assuming that there are 6 main control modules (i.e., BCU master 1, BCU master 2... BCU master 6) in the battery management system of a certain electric locomotive, corresponding to 6 battery clusters in the battery system of the electric locomotive respectively; in other embodiments, the number of main control modules can be flexibly increased or decreased according to the number of battery clusters and other actual requirements.

[0025] Specifically, in this embodiment, the first time interval is set to 100 ms. The vehicle controller of the electric locomotive respectively sends polling instructions to BCU master 1, BCU master 2... BCU master 6 of the battery management system (i.e., Figure 2 the "control and query instruction" with the message direction of VCU - BMS in ), to control the 6 main control modules to send the first battery information of the corresponding battery clusters at a time interval of 100 ms within each polling period, and in the order of BCU master 1 to 6 in sequence. This method is equivalent to polling a main control module every 100 ms through the vehicle controller to poll the first battery information of the corresponding battery cluster. In other embodiments, other orders can also be adopted according to requirements, such as the order of BCU master 6 to 1, etc., and no special restrictions are imposed here.

[0026] Specifically, the first battery information of the main control module is the battery information required for real - time vehicle control for power - on, power - off, charging or discharging control. As Figure 2 shown, the first battery information includes: the SOC of each single battery in the battery cluster, the SOH of each single battery in the battery cluster, the current of each single battery in the battery cluster, the total voltage of the battery cluster, insulation data (specifically including positive - pole insulation resistance, negative - pole insulation resistance and system insulation resistance - related data), extreme - value data of each single battery in the battery cluster, that is, voltage extreme - value data (including the highest voltage and the lowest voltage of the single battery) and temperature extreme - value data (including the highest temperature and the lowest temperature of the single battery), power - off request message (i.e., power - off request instruction), and liquid - cooling inlet and outlet data. Taking BCU master 1 to 6 as an example, when BCU master 1 starts to send its corresponding first battery information (i.e., Figure 2The communication type is event-based, and for six types of battery information with the ID range from 0x1001D00X to 0x1086D00X, at an interval of 100 ms, BCU master 2 (i.e., the next master) uploads the first battery information according to the polling command it receives; similarly, the first battery information of BCU masters 3 to 6 is polled in turn. Since the complete first battery information of each master module is required (this first battery information participates in the real-time control of the whole vehicle and its integrity and accuracy need to be ensured), the setting condition of the first time interval needs to be met when setting the first time interval, that is, to ensure that the first time interval is greater than or equal to the longest time for a single master module (i.e., any one of BCU masters 1 to 6 in this embodiment) to upload the first battery information. In this embodiment, the time interval for a single master module to upload the first battery information does not exceed 100 ms, and in other embodiments, it can be flexibly set according to the actual situation.

[0027] In this embodiment, the method further includes: each master module uploads the second and third battery information of the corresponding battery cluster at intervals of the second and third time intervals respectively.

[0028] Reference Figure 2 , the second battery information is the battery information required for fault location and diagnosis in the real-time control of the whole vehicle. As Figure 1 shown, the second battery information specifically includes: battery system status data and contactor status data (the contactor status data specifically includes data such as the conduction status of the main negative contactor, the conduction status of the main positive contactor, the charging contactor status, the heating contactor status, the water-cooling contactor status, etc.); the battery system status data includes data corresponding to the current state of the battery cluster; the current state of the battery cluster includes the charging state, the discharging state, the standby state, and the fault state. The information type of "for fault location and diagnosis" of the second battery information determines that this type of battery information must be actively uploaded, while the information type of "required for real-time control of the whole vehicle" reflects the real-time requirement for the second battery information; therefore, in this embodiment, on the basis of actively uploading the second battery information, the second time interval is set to a relatively short time interval (because fault location and diagnosis required for real-time control of the whole vehicle need to analyze the battery status data and contactor status data, and to avoid being unable to determine the fault, the second battery information needs to be uploaded at a short time interval, which is equivalent to uploading the second battery information at a short cycle), that is, 100 ms. When setting the second time interval, the setting condition of the second time interval needs to be met: 1) The second time interval is equal to the first time interval; 2) The second time interval is less than the first time interval and the first time interval is an integer multiple of the second time interval.

[0029] In this embodiment, a value range is set for the second time interval according to condition 1) and condition 2). Among them, if either condition 1) or condition 2) is satisfied, the real-time second battery information can be uploaded simultaneously with the real-time first battery information and jointly used as reference data for vehicle real-time control, avoiding the problem of waiting when the vehicle real-time control needs to use the second battery information and the first battery information simultaneously, or avoiding the situation where the second battery information and the first battery information used in vehicle real-time control cannot correspond in time.

[0030] The lower limit value of the value range of the second time interval is 50 ms; the upper limit value of the value range of the second time interval is 100 ms. In this embodiment, the second time interval is specifically set to 100 ms (the same as the first time interval numerically). In other embodiments, the second time interval can also be set to any value within its value range; for example, if the first time interval is set to 100 ms, the second time interval can be set to 50 ms. Taking the data uploaded in sequence by BCU master 1 to 6 as an example, when BCU master 1 starts to upload its corresponding second battery information, that is Figure 2 the communication type in it is periodic (100 ms). And the battery system status and contactor status information with the ID range of 0x1081D00X; at an interval of 100 ms, BCU master 2 (i.e., the next master) directly and actively uploads its corresponding second battery information; similarly, BCU masters 3 to 6 sequentially upload their corresponding second battery information respectively.

[0031] The third battery information is the battery information that is not required for vehicle real-time control. This third battery information does not need to participate in vehicle real-time control and only shows the status of the battery cluster and its subordinate single cells. Specifically, it includes at least one of the cumulative charge and discharge of the battery cluster, battery boundary data, and single cell information; the battery boundary data includes the upper and lower limit values of the single cell voltage and the upper and lower limit values of the single cell temperature; the single cell information includes the voltage and temperature of each single cell in the battery cluster. And since the third battery information does not participate in vehicle real-time control, there is no need to perform real-time judgment and processing on it, and only ensure that it is finally uploaded to the vehicle controller. This third battery information can upload data at a relatively long time interval (i.e., the third time interval). When setting the third time interval, the setting conditions of the third time interval need to be met: both the first and second time intervals are less than the third time interval. Taking BCU masters 1 to 6 as an example, when BCU master 1 starts to upload its corresponding third battery information, that is Figure 2The communication type is periodic (10s), and there are three types of battery information (i.e., voltage boundary data, battery information, and cumulative charge and discharge power) with the ID range from 0x18E4D00X to 0x18E6D00X. Every 10s, BCU master 2 (i.e., the next master) directly and actively uploads its corresponding third battery information. Similarly, BCU masters 3 to 6 sequentially upload their corresponding third battery information. Considering the necessity of uploading the third battery information to the vehicle controller, the third battery information is usually used for fault location and diagnosis, so it needs to be actively uploaded, but real-time performance is not required.

[0032] Specifically, in this embodiment, a value range is set for the third time interval according to this condition. The lower limit value of the value range of the third time interval is 1s, and the upper limit value is 60s. In this embodiment, the third time interval is set to 10s, which is much larger than the 100ms of the first and second time intervals (i.e., uploading the third battery information at a longer time interval, which is equivalent to uploading the third battery information in a long cycle). In other embodiments, the third time interval can also be set to other values on the basis of meeting the setting conditions of the third time interval. However, different from the uploading method of the first battery information, the second and third battery information are both periodically and actively uploaded, rather than being passively uploaded in response to the polling of the vehicle controller.

[0033] In summary, the vehicle controller obtains the complete first battery information of each of BCU masters 1 to 6 by setting a reasonable short-cycle polling (i.e., polling at the first time interval), and then obtains the second and third battery information of each of BCU masters 1 to 6 by combining the short-cycle (i.e., the second time interval) and long-cycle (i.e., the third time interval) active uploading methods, so as to perform real-time determination and processing on the battery information (i.e., the first and second battery information) that needs to participate in vehicle real-time control, and upload the battery information (i.e., the third battery information) that does not participate in vehicle real-time control. Thus, on the basis of ensuring the real-time performance of the battery information participating in vehicle real-time control, long-cycle communication is carried out on the battery information not required for vehicle real-time control to reduce unnecessary redundant data transmission, reduce the communication load rate, and relieve the communication pressure.

[0034] Embodiment of a communication system based on an electric locomotive battery management system This embodiment provides a technical solution for a communication system based on an electric locomotive battery management system. The system includes a processor, and the processor stores executable program instructions for implementing the communication method based on the electric locomotive battery management system in the communication method embodiment of the electric locomotive battery management system as described above.

[0035] Since the specific working mode and working principle of the communication system based on the electric locomotive battery management system in this embodiment have been described in detail in the above embodiments of the communication method based on the electric locomotive battery management system, they will not be elaborated here.

[0036] It should be understood that the above specific embodiments of the present invention are only used for exemplary illustration or explanation of the principle of the present invention, and do not constitute a limitation on the present invention.

Claims

1. A communication method based on a motor vehicle battery management system, characterized in that, Including: In each polling period, according to the first time interval, successively and respectively poll the first battery information of each battery cluster corresponding to each main control module of the battery management system; the first time interval is greater than or equal to the longest time for a single main control module to send the first battery information; It further includes: each main control module respectively sends the second and third battery information of the battery cluster corresponding to it at the second and third time intervals as the cycle; Both the first and second time intervals are less than the third time interval; The first battery information is the battery information required for real-time control of the whole vehicle for power-on, power-off, charging or discharging control; the second battery information is the battery information required for real-time control of the whole vehicle for fault location and diagnosis; the third battery information is the battery information not required for real-time control of the whole vehicle.

2. The communication method based on the battery management system of an electric locomotive according to claim 1, wherein, The second time interval is equal to the first time interval; or, the second time interval is less than the first time interval and the first time interval is an integer multiple of the second time interval.

3. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The method of successively and respectively polling each main control module of the battery management system according to the first time interval in each polling period includes: in each polling period, through the vehicle controller, successively send polling instructions to each main control module of the battery management system according to the first time interval.

4. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The first battery information includes: the SOC of each single battery in the battery cluster, the SOH of each single battery in the battery cluster, the current of each single battery in the battery cluster, the total voltage of the battery cluster, insulation data, the extreme value data of each single battery in the battery cluster, and a power-off request message.

5. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The second battery information includes: battery system status data and contactor status data; the battery system status data includes the data corresponding to the current state of the battery cluster; the current state of the battery cluster includes a charging state, a discharging state, a standby state, and a fault state.

6. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The third battery information includes at least one of the cumulative charge and discharge amount of the battery cluster, battery boundary data, and single battery information; The battery boundary data includes the upper and lower limit values of the voltage of the single battery and the upper and lower limit values of the temperature of the single battery; the single battery information includes the voltage and temperature of each single battery in the battery cluster.

7. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The lower limit value of the value range of the first time interval is 50 ms; the upper limit value of the value range of the first time interval is 200 ms.

8. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The lower limit value of the value range of the second time interval is 50 ms; the upper limit value of the value range of the second time interval is 100 ms.

9. The communication method based on the battery management system of an electric locomotive according to claim 1 or 2, characterized in that, The lower limit value of the value range of the third time interval is 1 s; the upper limit value of the value range of the third time interval is 60 s.

10. A communication system based on a motor vehicle battery management system, including a processor, characterized in that, The processor is used to execute a computer program to implement the steps of the communication method based on the battery management system of the electric locomotive according to any one of claims 1-9.

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