CN-121984194-A - Battery management system

Abstract

The invention provides a battery management system capable of suppressing erroneous judgment of deviation abnormality of a current sensor when a battery current oscillates. A battery management system for managing a battery includes a main current sensor and a sub current sensor for measuring a current of the battery, a1 st processing unit for calculating a1 st movement average line from a plurality of current values measured by the main current sensor and calculating a1 st deviation which is a deviation between a current value measured by the main current sensor and the 1 st movement average line, a2 nd processing unit for calculating a2 nd movement average line from a plurality of current values measured by the sub current sensor and calculating a2 nd deviation which is a deviation between a current value measured by the sub current sensor and the 2 nd movement average line, and a 3 rd processing unit for determining a deviation abnormality of the main current sensor and the sub current sensor based on the 1 st deviation and the 2 nd deviation.

Inventors

• Gang Tian Zheming

Assignees

• 丰田自动车株式会社

Dates

Publication Date

20260505

Application Date

20251023

Priority Date

20241031

Claims (3)

1. 1. A battery management system that manages a battery, the battery management system comprising: a main current sensor and a sub-current sensor for measuring a current of the battery; A1 st processing unit that calculates a1 st movement average line from a plurality of current values measured by the main current sensor, and calculates a1 st deviation that is a deviation between a current value measured by the main current sensor and the 1 st movement average line; a 2 nd processing unit for calculating a 2 nd shift average line from a plurality of current values measured by the sub-current sensor, and calculating a 2 nd deviation which is a deviation between a current value measured by the sub-current sensor and the 2 nd shift average line, and And a3 rd processing unit that determines that the deviation of the main current sensor and the sub current sensor is abnormal based on the 1 st deviation and the 2 nd deviation.
2. 2. The battery management system of claim 1, wherein, The 3 rd processing unit calculates a1 st integrated value obtained by integrating the 1 st deviation over a predetermined period and a2 nd integrated value obtained by integrating the 2 nd deviation over the predetermined period, and determines that the deviation abnormality exists in the main current sensor and the sub current sensor when the 1 st integrated value is smaller than a1 st threshold and the 2 nd integrated value is smaller than a2 nd threshold.
3. 3. The battery management system according to claim 2, further comprising: A 4 rd processing unit that calculates a3 rd deviation as a deviation between the current value measured by the main current sensor and the current value measured by the sub current sensor, The 3 rd processing unit performs the determination based on the 1 st integrated value and the 2 nd integrated value when the number of times the 3 rd deviation exceeds the 3 rd threshold value is equal to or greater than a predetermined number of times.

Description

Battery management system Technical Field The present invention relates to a battery management system that manages batteries. Background Patent document 1 discloses a current sensor diagnostic device that diagnoses errors of 2 current sensors configured to measure the current value of the same current of a battery. In this current sensor diagnostic apparatus, the abnormality of the deviation of the current sensor is determined based on the deviations of the 2 battery currents measured by the 2 current sensors, respectively. Patent document 1 Japanese patent application laid-open No. 2021-515194 Disclosure of Invention When the battery current oscillates (for example, when the battery mounted on the vehicle oscillates due to control of a Motor Generator (MG) or the like), if the determination is made based on only the deviations of the 2 battery currents measured by the 2 current sensors, there is a possibility that the deviation abnormality of the current sensors may be misdetermined due to the influence of the oscillation. The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a battery management system capable of suppressing erroneous determination of a deviation abnormality of a current sensor when a battery current oscillates. In order to solve the above-described problems, one aspect of the present invention is a battery management system for managing a battery, the battery management system including a main current sensor and a sub-current sensor for measuring a current of the battery, a 1 st processing unit for calculating a 1 st movement average line from a plurality of current values measured by the main current sensor and calculating a 1 st deviation that is a deviation between a current value measured by the main current sensor and the 1 st movement average line, a 2 nd processing unit for calculating a 2 nd movement average line from a plurality of current values measured by the sub-current sensor and calculating a 2 nd deviation that is a deviation between a current value measured by the sub-current sensor and the 2 nd movement average line, and a 3 rd processing unit for determining a deviation abnormality of the main current sensor and the sub-current sensor based on the 1 st deviation and the 2 nd deviation. Effects of the invention According to the battery management system of the present invention, the deviation between the current and the moving average line of the battery current is calculated in each of the main current sensor and the sub current sensor which are provided in a redundant manner for measuring the battery current, and the deviation abnormality of the current sensor is determined based on the deviation. This can suppress erroneous determination of the abnormality in the deviation of the current sensor when the battery current oscillates. Drawings Fig. 1 is a schematic configuration diagram of a battery management system according to an embodiment of the present invention. Fig. 2A is a flowchart of the process of the deviation abnormality determination control executed by the processing unit of the battery management system. Fig. 2B is a flowchart of the process of the deviation abnormality determination control executed by the processing unit of the battery management system. Fig. 3 is a schematic diagram of accumulating deviations between a moving average line and a battery current. Fig. 4 is a schematic diagram of current deviation when the battery current oscillates. Detailed Description In the battery management system according to the present invention, among 2 current sensors that are provided redundantly for measuring a battery current, a deviation between a moving average of the battery current and a sampling current is calculated using the currents sampled in a short period, and a deviation abnormality of the current sensor is determined based on the deviation. An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. < Embodiment > Structure Fig. 1 is a schematic configuration diagram illustrating a battery management system 20 according to an embodiment of the present invention. The battery management system 20 illustrated in fig. 1 includes a main current sensor 21, a sub-current sensor 22, and a processing unit 23, and controls and manages the state of the battery 10. The battery 10 is a secondary battery for supplying electric power to an electric load (not shown) such as a device or equipment connected to the battery. A battery pack composed of a lithium ion battery, a lead storage battery, or the like is used for the battery 10. The main current sensor 21 is configured to measure the current flowing through the battery 10 in a normal case. The sub-current sensor 22 is a redundant structure for measuring the current flowing through the battery 10 in place of the main current sensor 21, for example, when the main current sens