Current acquisition system for battery system
By using a combination of shunt and temperature sensors in the battery management module, the problems of high cost and sensitivity to magnetic field interference are solved, and the current acquisition effect with low cost, high stability and high reliability are achieved.
Patent Information
- Application Number
- CN202421496004.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-27
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-06-27
AI Technical Summary
In existing battery management modules, the high cost of Hall sensors and sensitivity to external magnetic field interference limit their application in large-scale production and cost-sensitive markets, and affects the stability and reliability of current sampling.
Using a combination of a shunt and a temperature sensor, the shunt is directly connected to the positive electrode of the battery cell through the shunt, the voltage output is collected, and the temperature of the shunt is monitored through the temperature sensor, and the real-time current value is calculated according to Ohm's law.
A low-cost, high stability and high reliability current acquisition system is realized, reducing the overall cost of the system and avoiding the impact of magnetic field interference on measurements.
Smart Images
Figure CN222994556U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of battery management, and particularly relates to a current acquisition system for a battery system. Background Art
[0002] With the increasing global emphasis on sustainable energy and environmental protection, the electric vehicle (EV) industry has entered a golden era of rapid development. The performance, safety, and user experience of electric vehicles largely depend on the core of their power systems, namely the battery management module (BMS).
[0003] The BMS is responsible for monitoring and managing the charging and discharging processes of the battery to ensure that the battery operates in the best state, thereby improving the overall performance of the electric vehicle. By real-time monitoring the changes in the internal current of the battery, the BMS can promptly detect and respond to potential fault states such as short circuits and overcurrents, thus ensuring the safe operation of the battery and the vehicle. At the same time, accurate current data acquisition helps to evaluate the performance of the battery, including key parameters such as capacity and state of health, so as to enhance the optimized management and performance of the battery. In addition, by real-time monitoring the current, the BMS can avoid overcharging and over-discharging of the battery, reduce battery loss, extend the service life of the battery, and improve its cycle stability and reliability.
[0004] Hall sensors are widely used in current detection due to their high sensitivity and response speed, but there are also some obvious limitations. The high cost of Hall sensors limits their popularity in application scenarios such as large-scale production and cost-sensitive markets. Secondly, Hall sensors are easily affected by external magnetic fields, which may cause measurement errors or interference, affecting the stability and reliability of current sampling. Summary of the Utility Model
[0005] The purpose of the utility model is to provide a current acquisition system for a battery system, and this technical solution can provide a cost-effective and stable current acquisition system.
[0006] To achieve the above purpose, the basic solution provided by the utility model includes a battery management module, which is connected to the positive and negative electrodes of the battery unit; the battery management module is also connected to a shunt, one end of the shunt is connected to the positive electrode of the battery unit, and the other end is connected to the negative electrode of the battery unit, for collecting voltage output and transmitting it to the battery management module; a temperature sensor is also arranged between the battery management module and the shunt, for outputting a temperature value to the battery management module; the battery management module is used to receive the signals of the shunt and the temperature sensor.
[0007] Principle and beneficial effects of the basic solution: Through the combined use of a shunt and a temperature sensor, the temperature sensor can directly collect the real-time temperature, and the shunt can directly collect the real-time voltage and output it to the battery management module. The battery management module can obtain the resistance value based on the temperature and calculate the real-time current value according to Ohm's law and the real-time voltage.
[0008] The shunt can be directly connected to the positive electrode of the battery cell, so as to accurately collect the current change during the charging and discharging process of the battery, thereby realizing the real-time monitoring of the battery current. A temperature sensor is set between the battery management module and the shunt to monitor the temperature of the shunt in real time. Since the resistance value changes with temperature, the addition of the temperature sensor can adjust the current measurement value according to the temperature change, thereby improving the accuracy of current collection. In addition, through a reasonable shunt design, a stable current input can be ensured, and the accuracy and reliability of data collection can be improved.
[0009] Compared with a Hall sensor, the combination of a shunt and a temperature sensor may have a lower cost, which helps to reduce the overall cost of the system. At the same time, it is not easily affected by magnetic fields and can maintain the required monitoring performance.
[0010] As an implementable preferred solution, the battery management module is connected to the positive electrode of the battery cell through the S1 interface and to the negative electrode of the battery cell through the S2 interface.
[0011] As an implementable preferred solution, other loads are also set between the battery management module and the negative electrode of the battery cell. The other loads include a motor, a controller, a pre-charge circuit, a safety circuit breaker or a main switch.
[0012] As an implementable preferred solution, a first relay is set at the S1 interface, and a second relay is set at the S2 interface. Both the first relay and the second relay are used to control the on-off of the current.
[0013] As an implementable preferred solution, the battery management module is set with a temperature threshold and a current value threshold. When the temperature value or the current value exceeds the threshold range, the battery management module will send an alarm signal.
[0014] As an implementable preferred solution, the battery management module is set on the vehicle end and is electrically connected to the vehicle end. Description of the Drawings
[0015] Figure 1 Shows a schematic structural diagram of a current acquisition system for a battery system.
[0016] Figure 2 Shows a schematic flow diagram of a current acquisition system for a battery system. Detailed Implementation Modes
[0017] The technical solution of the present application will be further described in detail through specific embodiments as follows:
[0018] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "arrangement" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection (including various forms of mechanical connections, such as couplings or gear pairs, etc.), or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.
[0019] Reference numerals: battery management module 101, shunt 102, other loads 103, first relay 104, second relay 105, temperature sensor 106.
[0020] Refer to Figure 1 , a current acquisition system for a battery system, including: battery management module 101, shunt 102, other loads 103, first relay 104, second relay 105, temperature sensor 106.
[0021] The battery management module 101 is arranged on the vehicle end and is electrically connected to the vehicle end.
[0022] The battery management module 101 is connected to the positive electrode of the battery unit through the S1 interface and to the negative electrode of the battery unit through the S2 interface. A first relay 104 is arranged at the S1 interface, and a second relay 105 is arranged at the S2 interface. Both the first relay 104 and the second relay 105 are used to control the on-off of the current. An other load 103 is arranged between the battery management module 101 and the negative electrode of the battery unit. The other load can be an electric motor, which manages the speed and torque of the electric motor through a controller to output the power source of the electric vehicle and is responsible for rotating the wheels to provide driving force; the controller, as the "brain" of the electric motor, receives instructions from the BMS and adjusts the power output of the electric motor to manage the operation of the electric motor and control operations such as acceleration, deceleration, and braking; the pre-charge circuit pre-charges the capacitor when connecting to the high-voltage battery to smooth the current, reduce current impact, and extend the service life of electrical components to ensure the safe connection of the circuit when the electric vehicle starts; the safety circuit breaker or main switch disconnects the circuit in case of a fault or emergency in the battery system to protect the vehicle and passengers.
[0023] The battery management module 101 is also connected to a shunt 102. One end of the shunt 102 is connected to the positive electrode of the battery unit, and the other end of the shunt 102 is connected to the negative electrode of the battery unit, and is used to collect the voltage and output it to the battery management module.
[0024] A temperature sensor 106 is also provided between the battery management module 101 and the shunt 102 to measure the temperature of the shunt. Preferably, an NTC temperature sensor is used to output the temperature value to the battery management module 101. The battery management module 101 obtains the resistance value by referring to the specification table based on the temperature, collects the voltage value through the shunt, and finally obtains the real-time current value according to Ohm's law.
[0025] The battery management module 101 performs threshold diagnosis on the collected data, including temperature threshold and current value threshold, to identify and alarm potential fault states. Specifically, over-range and zero-drift diagnosis are performed on the calculated original current value, thresholds are set, and an alarm signal is issued when the threshold is exceeded. Thresholds are set for the directly measured temperature, and an alarm signal is issued when the threshold is exceeded; thresholds are set for the original current value, and an over-range or zero-drift alarm signal is issued if it is outside the threshold range.
[0026] Refer to Figure 2 , the implementation method of this system is as follows:
[0027] Step 301, collect the temperature through the temperature sensor 106 and obtain the resistance value according to the specification.
[0028] Step 302, directly collect the voltage using the shunt 102 and the resistance value obtained in step 301 to obtain the original current value.
[0029] Step 303, diagnose the fault of the shunt 102 according to the preset conditions. For the directly measured temperature, set a threshold, and issue an alarm signal when the threshold is exceeded; for the original current value, set a threshold, and issue an over-range or zero-drift alarm signal when the threshold is exceeded.
[0030] Step 304, output the real-time current value.
[0031] A shunt, a temperature sensor, at least two relays, other loads, and a battery management module.
[0032] The battery management module performs threshold diagnosis on the temperature collected by the temperature sensor, and issues an alarm signal when the threshold is exceeded.
[0033] The above content is only an embodiment of the present utility model. Specific structures and common knowledge such as characteristics that are well-known in the art are not described in detail herein. Those of ordinary skill in the art know all the common general technical knowledge in the technical field to which the utility model belongs before the filing date or the priority date, are able to obtain all the prior art in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in this application, combine their own abilities to complete and implement this solution. Some typical well-known structures or well-known methods should not become an obstacle for those of ordinary skill in the art to implement this application. It should be noted that for those skilled in the art, without departing from the structure of the present utility model, several deformations and improvements can still be made, and these should also be regarded as the protection scope of the present utility model, and these will not affect the implementation effect of the present utility model and the practicality of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners and other records in the specification can be used to interpret the content of the claims.
Claims
1. A current acquisition system for a battery system, characterized in that: It includes a battery management module, which is connected to the positive and negative electrodes of the battery cell; the battery management module is also connected to a shunt, one end of the shunt is connected to the positive electrode of the battery cell, and the other end is connected to the negative electrode of the battery cell, and is used to collect voltage output and transmit it to the battery management module; a temperature sensor is also arranged between the battery management module and the shunt, which is used to output the temperature value to the battery management module; the battery management module is used to receive signals from the shunt and the temperature sensor.
2. A current acquisition system for a battery system according to claim 1, characterized in that: The battery management module is connected to the positive electrode of the battery unit through the S1 interface and is connected to the negative electrode of the battery unit through the S2 interface.
3. A current acquisition system for a battery system according to claim 2, characterized in that: Other loads are also arranged between the battery management module and the negative electrode of the battery unit. The other loads include a motor, a controller, a pre-charging circuit, a safety circuit breaker or a main switch.
4. The current acquisition system for a battery system according to claim 3, characterized in that: A first relay is provided at the S1 interface, and a second relay is provided at the S2 interface. Both the first relay and the second relay are used to control the on and off of current.
5. The current acquisition system for a battery system according to claim 1, characterized in that: The battery management module is provided with a temperature threshold and a current value threshold. When the temperature value or the current value exceeds the threshold range, the battery management module will send out an alarm signal.
6. The current acquisition system for a battery system according to claim 1, characterized in that: The battery management module is arranged on the vehicle end and is electrically connected to the vehicle end.