Battery system

Abstract

The battery system may include a plurality of battery packs, each containing a plurality of battery cells; a plurality of battery management systems connected to the plurality of battery packs; and a rack battery management system that transmits control commands to the plurality of battery management systems and receives a plurality of monitoring information in response to the control commands from the plurality of battery management systems. Each of the plurality of battery management systems may include a dual transformer that includes two BMICs (Battery Management ICs) connected to a corresponding battery pack among the plurality of battery packs and which generate monitoring information for the corresponding battery pack in response to the control command, and a first winding connected to a first BMIC of the two BMICs, and a second winding connected to a second BMIC of the two BMICs. The grounds of the first winding and the grounds of the second winding may be isolated from each other.

Description

Technical Field

[0001] [Cross-Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0174491 filed on December 5, 2023, and all contents disclosed in the documents of the said Korean patent application are included as part of the present specification.

[0002] The present disclosure relates to a battery system.

Background Art

[0003] A Battery Management System (BMS) is connected to a plurality of battery cells constituting a battery pack, can monitor the plurality of battery cells, and control charging and discharging of the battery pack. The number of Battery Management ICs (BMICs) that monitor the plurality of battery cells may be two or more according to the number of the plurality of battery cells.

[0004] A transformer may be used for two or more BMICs to transmit and receive information to and from the outside of the BMS. An insulation distance between the high voltage side and the low voltage side of the transformer shall be ensured, and a transformer corresponding to each of the two or more BMICs is required. This leads to the problem that the size of the PCB on which the BMS is mounted increases, and the BMS manufacturing cost also increases.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure aims to provide a battery system capable of minimizing an increase in PCB size and also minimizing an increase in manufacturing cost when manufacturing a BMS including two or more BMICs.

Means for Solving the Problems

[0006] A battery system according to one feature of this disclosure may include a plurality of battery packs, each containing a plurality of battery cells; a plurality of battery management systems connected to the plurality of battery packs; and a rack battery management system that transmits control commands to the plurality of battery management systems and receives a plurality of monitoring information in response to the control commands from the plurality of battery management systems. Each of the plurality of battery management systems may include two BMICs (Battery Management ICs) connected to a corresponding battery pack among the plurality of battery packs and which generate monitoring information for the corresponding battery pack in response to the control command; and a dual transformer including a first winding connected to a first BMIC and a second winding connected to a second BMIC of the two BMICs. The grounds of the first winding and the grounds of the second winding may be isolated from each other.

[0007] The first dual transformer of the first battery management system among the plurality of battery management systems may further include a third winding insulated-linked to the first winding and connected to the rack battery management system, and a fourth winding insulated-linked to the second winding and connected to the second battery management system among the plurality of battery management systems. The second battery management system may include a second dual transformer including a fifth winding connected to the fourth winding, and a sixth winding insulated-linked to the fifth winding, and a third BMIC connected to the sixth winding. The second battery management system may further include a fourth BMIC connected to a corresponding battery pack among the plurality of battery packs. The second dual transformer may further include a seventh winding connected to the fourth BMIC, and an eighth winding insulated-linked to the seventh winding. The ground of the sixth winding and the ground of the seventh winding may be isolated from each other. The third BMIC and the fourth BMIC may each be connected to half of the plurality of battery cells of the corresponding battery pack.

[0008] The first battery management system may further include a ninth and a tenth winding isolated between the first BMIC and the second BMIC. A signal transmitted to the third winding is provided to the first BMIC via the first winding, the first BMIC transmits the signal to the second BMIC via the ninth and tenth windings, and the second BMIC can transmit the signal to the second battery management system via the second and fourth windings. The signal transmitted to the third winding can instruct the control command. A first signal transmitted from the second battery management system to the fourth winding is provided to the second BMIC via the second winding, the second BMIC transmits a second signal to the first BMIC via the ninth and tenth windings, which is the first BMIC with monitoring information it has generated added to the first signal, and the first BMIC can transmit a third signal to the rack battery management system via the first and third windings, which is the first BMIC with monitoring information it has generated added to the second signal. The first signal may include monitoring information from the second battery management system.

[0009] The second battery management system may include a second dual transformer comprising a third BMIC and a fourth BMIC connected to a corresponding battery pack, a fifth winding connected to the fourth winding and a sixth winding isolatedly linked to the fifth winding and connected to the third BMIC, a seventh winding connected to the fourth BMIC and an eighth winding isolatedly linked to the seventh winding, and an eleventh and twelfth windings isolatedly linked between the third BMIC and the fourth BMIC. The grounds of the sixth winding and the seventh winding may be isolated from each other. A signal transmitted to the fifth winding may be provided to the third BMIC via the sixth winding, the third BMIC may transmit the signal to the fourth BMIC via the eleventh and twelfth windings, and the fourth BMIC may transmit the signal to the third battery management system among the plurality of battery management systems via the seventh and eighth windings. A first signal transmitted from the third battery management system to the eighth winding among the plurality of battery management systems is provided to the fourth BMIC via the seventh winding. The fourth BMIC adds monitoring information it has generated to the first signal and transmits a second signal, which is transmitted to the third BMIC via the eleventh and twelfth windings. The third BMIC adds monitoring information it has generated to the second signal and transmits a third signal, which is transmitted to the first battery management system via the fifth and sixth windings. The first signal may include monitoring information from the third battery management system.

[0010] Each of the dual transformers of the plurality of battery management systems may further include a third winding insulated-linked to the first winding and connected to the rack battery management system, and a fourth winding insulated-linked to the second winding and connected to the rack battery management system. [Effects of the Invention]

[0011] This disclosure provides a battery system that minimizes the increase in PCB size and the increase in manufacturing costs when manufacturing a BMS that includes two or more BMICs. [Brief explanation of the drawing]

[0012] [Figure 1] Block diagram showing a battery system according to one embodiment. [Figure 2] This figure shows a partial configuration of a battery system according to one embodiment. [Figure 3] This shows a configuration for communication between multiple BMICs according to one embodiment. [Figure 4] This shows the sequence of control command transmissions from an MCU to multiple BMICs according to one embodiment. [Figure 5] This shows the sequence of monitoring information transmission from multiple BMICs to the MCU according to one embodiment. [Figure 6] Block diagram showing a battery system according to one embodiment. [Figure 7] This figure shows a partial configuration of a battery system according to one embodiment. [Modes for carrying out the invention]

[0013] Where it is determined that a specific description of prior art relating to the embodiments disclosed herein would obscure the essence of the embodiments disclosed herein, such detailed description will be omitted. Furthermore, the accompanying drawings are provided solely to facilitate a basic understanding of the embodiments disclosed herein, and it should be understood that the accompanying drawings do not limit the technical ideas disclosed herein and include all modifications, equivalents, or substitutions that fall within the concept and scope of the present invention.

[0014] Terms including ordinal numbers such as "first," "second," etc., can be used to describe various components, but the components are not limited by such terms. These terms are used solely for the purpose of distinguishing one component from others.

[0015] When a certain component is referred to as being "coupled to" or "connected to" another component, it should be understood that it may be directly coupled or connected to the other component, or there may be other intermediate components present. On the other hand, when a certain component is referred to as being "directly coupled to" or "directly connected to" another component, it should be understood that no other intermediate components are present.

[0016] In the present application, terms such as "comprising" or "having" are intended to specify the presence of the features, numbers, steps, operations, components, parts or combinations thereof described in the specification, and shall be understood as not precluding the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0017] Figure 1 is a block diagram showing a battery system according to an embodiment.

[0018] The battery system 1 may include a plurality of battery packs 10_1 to 10_3, a plurality of BMSs 20_1 to 20_3, a rack BMS (Rack Battery Management System, RBMS) 30, a switch device 40, and a current sensor 50. Although Figure 1 illustrates that the battery system 1 includes three battery packs 10_1 to 10_3, the invention is not limited thereto. The present invention can be applied to a battery system including two or more battery packs.

[0019] The plurality of battery packs 10_1 to 10_3 are connected in series between the two output terminals (P+, P-) of the battery system 1. Each of the plurality of battery packs 10_1 to 10_3 may include a plurality of battery cells (for example, CE1 to CEn) connected in series (n is a natural number of 2 or more).

[0020] Each of the multiple BMS20_1, 20_2, and 20_3 is connected to each of the multiple battery packs 10_1 to 10_3, and can measure the cell voltage of each of the multiple battery cells (CE1 to CEn) of the corresponding battery pack and transmit the multiple cell voltages of each of the multiple battery cells (CE1 to CEn) of the multiple battery packs 10_1 to 10_3 to the rack BMS30. Although not shown in Figure 1, the battery system 1 may further include multiple temperature sensors to measure the temperature of each of the multiple battery packs 10_1 to 10_3, multiple current sensors to measure the current flowing through each of the multiple battery packs 10_1 to 10_3, and so on. The multiple temperature sensors can provide signals indicating the measured temperature to the multiple BMS20_1, 20_2, 20_3, or the rack BMS30. The multiple current sensors can provide signals indicating the measured current to the multiple BMS20_1, 20_2, 20_3, or the rack BMS30. When multiple BMSs 20_1, 20_2, and 20_3 receive signals from multiple temperature sensors and multiple current sensors, the rack BMS 30 can request information on temperature and current from the multiple BMSs 20_1, 20_2, and 20_3 in a daisy-chain manner, and the multiple BMSs 20_1, 20_2, and 20_3 can transmit values ​​to the rack BMS 30 corresponding to the received signals. In the following description, the information provided from the BMS to the rack BMS may include monitoring information, such as cell voltage, pack temperature, and pack current, with at least one of these being included.

[0021] Rack BMS 30 can send control commands to multiple BMSs 20_1, 20_2, and 20_3. Multiple BMSs 20_1, 20_2, and 20_3 perform actions in response to the received control commands and can transmit information obtained from those actions, such as monitoring information, to Rack BMS 30. Figure 1 shows that Rack BMS 30 sends control commands to multiple BMSs 20_1, 20_2, and 20_3 according to a daisy-chain method and receives responses to the control commands from multiple BMSs 20_1, 20_2, and 20_3. The daisy-chain method is just one example of a communication method applicable to the present invention, and the present invention is not limited thereto. Rack BMS 30 generates a control command, for example, a command to measure the voltages of multiple battery cells, and this control command is transmitted to BMS 20_1, BMS 20_2, and BMS 20_3 in that order using the daisy-chain method. BMS20_3, being the last to transmit, recognizes that there is no BMS to transmit a control command to next and takes action in response to the received control command, for example, by measuring the voltage of multiple battery cells, generating multiple cell voltage values ​​for battery pack 10_3, and sending the multiple cell voltage values ​​of battery pack 10_3 to BMS20_2 in response to the control command. BMS20_2 also generates multiple cell voltage values ​​for battery pack 10_2 in response to the control command and sends the multiple cell voltage values ​​of battery pack 10_2 along with the multiple cell voltage values ​​of battery pack 10_3 received from BMS20_3 to BMS10_1. BMS20_1 also generates multiple cell voltage values ​​for battery pack 10_1 in response to the control command and sends the multiple cell voltage values ​​of battery pack 10_1 along with the multiple cell voltage values ​​of the two battery packs 10_2 and 10_3 received from BMS20_2 to the rack BMS30.

[0022] The rack BMS 30 can control the switching operation of the switch device 40 based on information received from the plurality of BMSs 20_1, 20_2, 20_3 and information provided from the outside. The rack BMS 30 can close the switch device 40 for a discharge operation of supplying power from the plurality of battery packs 10_1 to 10_3 to the outside, and a charge operation of supplying power from the outside to the plurality of battery packs 10_1 to 10_3, and can open the switch device 40 in a resting state where there is a problem with the plurality of battery packs 10_1 to 10_3 or no power operation is performed. The rack BMS 30 can provide a switching signal (SWS) for controlling the switching operation of the switch device 40 to the switch device 40.

[0023] The current sensor 50 can measure the current flowing through the plurality of battery packs 10_1 to 10_3 and provide the measured current to the rack BMS 30. The current sensor 50 can transmit a sensing signal (IS) indicating the current measured at each predetermined monitoring cycle to the rack BMS 30.

[0024] The configuration shown in Figure 1 illustrates an embodiment according to the present invention, and only the necessary configuration is shown. The battery system 1 may include various configurations in addition to the configuration shown in Figure 1.

[0025] Figure 2 is a diagram showing a partial configuration of a battery system according to an embodiment.

[0026] In Figure 2, partial configurations of the plurality of BMSs 20_1, 20_2, 20_3 and the rack BMS 30 are shown.

[0027] Each of the multiple BMS20_1, 20_2, and 20_3 units can include two BMICs (211, 212, 221, 222, 231, 232) and dual transformers 213, 223, 233. Figure 2 shows an embodiment in which a daisy-chain is implemented such that control commands are transmitted in the order rack BMS30->BMS20_1->BMS20_2->BMS20_3, and monitoring information generated as a response to the control commands is transmitted in the order BMS20_3->BMS20_2->BMS20_1->rack BMS30. This is an example to illustrate the invention, and the invention is not limited thereto. For example, control commands can be transmitted in the order rack BMS30->BMS20_1->BMS20_2->BMS20_3, and monitoring information generated as a response to the control commands can be transmitted along with the control commands. BMS20_3 can transmit control commands and monitoring information received from BMS20_1 and BMS20_2, followed by monitoring information generated by BMS20_3 itself, to the rack BMS30.

[0028] The rack BMS 30 can control charging and discharging of the battery system 1, cell balancing, and protective actions against abnormal events in the battery system 1. Abnormal events can include abnormal events such as overvoltage, overcurrent, and overheating occurring in multiple battery packs 10_1 to 10_3. The rack BMS 30 includes a transformer 31 and an MCU 32. Control commands can be sent from the MCU 32 to the BMS 20_1 via the transformer 31, and monitoring information can be received from the BMS 20_1 to the MCU 32 via the transformer 31. The MCU 32 can generate and send control commands to collect the monitoring information necessary to control the battery system 1, control the charging and discharging of the multiple battery packs 10_1 to 10_3 using the received monitoring information, determine which battery cells require cell balancing and control cell balancing, and sense abnormal events and control protective actions, such as opening the switch device 40.

[0029] BMS20_1 may include two BMIC1_1~2 (211, 212) and a dual transformer 213. BMIC1_1(211) is connected to half of the battery cells of the battery pack 10_1 and can measure the cell voltage of the connected battery cells. BMIC1_2(212) is connected to the other half of the battery cells of the battery pack 10_1 and can measure the cell voltage of the connected battery cells. Each of BMIC1_1(211) and BMIC1_2(212) includes four pins (P1, M1, P2, M2). Two pins (P1, M1) of BMIC1_1(211) are connected to both ends of the first winding 301 of the dual transformer 213, and two pins (P1, M1) of BMIC1_2(212) are connected to both ends of the third winding 311 of the dual transformer 213. The ends of the second winding 302 of the double transformer 213 are connected to the ends of the first winding 361 of the transformer 31. The ends of the second winding 362 of the transformer 31 are connected to the MCU 32. The ends of the fourth winding 312 of the double transformer 213 are connected to the ends of the second winding 322 of the double transformer 223 of the BMS 20_2.

[0030] The first winding 301 and the second winding 302 of the dual transformer 213 are insulated links from each other, and the third winding 311 and the fourth winding 312 of the dual transformer 213 are also insulated links from each other. In this disclosure, an isolated link can mean that two windings constituting the transformer are insulated from each other and coupled so that signals can be transmitted between the two windings. The ground (GND1) of the first winding 301 and the ground (GND2) of the third winding 311 are isolated from each other. For example, the ground (GND1) of the first winding 301 may be the negative electrode voltage level of the battery cell with the lowest potential among a plurality of battery cells connected to BMIC1_1(211). The ground (GND2) of the third winding 311 may be the negative electrode voltage level of the battery cell with the lowest potential among a plurality of battery cells connected to BMIC1_2(212).

[0031] The BMS20_2 may include two BMIC2_1~2 (221, 222) and a dual transformer 223. BMIC2_1(221) is connected to half of the battery cells of the battery pack 10_2 and can measure the cell voltage of the connected battery cells. BMIC2_2(222) is connected to the other half of the battery cells of the battery pack 10_2 and can measure the cell voltage of the connected battery cells. Each of BMIC2_1(221) and BMIC2_2(222) includes four pins (P1, M1, P2, M2). Two pins (P1, M1) of BMIC2_1(221) are connected to both ends of the first winding 321 of the dual transformer 223, and two pins (P1, M1) of BMIC2_2(222) are connected to both ends of the third winding 331 of the dual transformer 223. The ends of the second winding 322 of the double transformer 223 are connected to the ends of the second winding 312 of the double transformer 213 of BMIC1_1(211).

[0032] The first winding 321 and the second winding 322 of the dual transformer 223 are insulated from each other, and the third winding 331 and the fourth winding 332 of the dual transformer 223 are also insulated from each other. The ground of the first winding 321 (GND3) and the ground of the third winding 331 (GND4) are isolated from each other. For example, the ground of the first winding 321 (GND3) can be the negative electrode voltage level of the battery cell with the lowest potential among multiple battery cells connected to BMIC2_1(221). The ground of the third winding 331 (GND4) can be the negative electrode voltage level of the battery cell with the lowest potential among multiple battery cells connected to BMIC2_2(222).

[0033] The BMS20_3 may include two BMIC3_1~2 (231, 232) and a dual transformer 233. BMIC3_1 (231) is connected to half of the battery cells of the battery pack 10_3 and can measure the cell voltage of the connected battery cells. BMIC3_2 (232) is connected to the other half of the battery cells of the battery pack 10_3 and can measure the cell voltage of the connected battery cells. Each of BMIC3_1 (231) and BMIC3_2 (232) includes four pins (P1, M1, P2, M2). Two pins (P1, M1) of BMIC3_1 (231) are connected to the ends of the first winding 341 of the dual transformer 233, and a resistor 234 is connected between the two pins (P1, M1) of BMIC3_2 (232). BMIC3_2(232) is located at the end of a daisy chain and can sense the voltage difference generated by the resistor 234 between two pins (P1, M1) to recognize that it is the end of the daisy chain. The ends of the first winding 351 and the second winding 352 of the dual transformer 223 may be floating, as shown in Figure 2. The first winding 341 and the second winding 342 of the dual transformer 233 are insulated from each other, and the ground (GND5) of the first winding 341 can be the negative voltage level of the battery cell with the lowest potential among the multiple battery cells connected to BMIC3_1(231). BMS20_3 may include a single transformer instead of the dual transformer 233.

[0034] The two pins (P2, M2) of BMIC1_1(211) and the two pins (P2, M2) of BMIC1_2(212) can be isolated from each other, the two pins (P2, M2) of BMIC2_1(221) and the two pins (P2, M2) of BMIC2_2(222) can be isolated from each other, and the two pins (P2, M2) of BMIC3_1(231) and the two pins (P2, M2) of BMIC3_2(232) can be isolated from each other.

[0035] Figure 3 shows a configuration for communication between multiple BMICs according to one embodiment.

[0036] Figure 3 shows several transformers 370, 380, and 390 that provide an isolated link between BMIC1_1(211) and BMIC1_2(212), an isolated link between BMIC2_1(221) and BMIC2_2(222), and an isolated link between BMIC3_1(231) and BMIC3_2(232).

[0037] The ends of the first winding 371 of transformer 370 are connected to the two pins (P2, M2) of BMIC1_1(211), and the ends of the second winding 372 of transformer 370 are connected to the two pins (P2, M2) of BMIC1_2(212). The ends of the first winding 381 of transformer 380 are connected to the two pins (P2, M2) of BMIC2_1(221), and the ends of the second winding 382 of transformer 380 are connected to the two pins (P2, M2) of BMIC2_2(222). The ends of the first winding 391 of transformer 390 are connected to the two pins (P2, M2) of BMIC3_1(231), and the ends of the second winding 392 of transformer 390 are connected to the two pins (P2, M2) of BMIC3_2(232).

[0038] Figure 4 shows the transmission sequence of control commands from an MCU to multiple BMICs according to one embodiment.

[0039] As shown by the two arrows 41 and 42 in Figure 4, the MCU32 can send control commands in the following order: BMIC1_1(211), BMIC1_2(212), BMIC2_1(221), BMIC2_2(222), BMIC3_1(231), and BMIC3_2(232).

[0040] Figure 5 shows the sequence of monitoring information transmission from multiple BMICs to the MCU according to one embodiment.

[0041] As shown by the two arrows 51 and 52 in Figure 5, monitoring information can be sent to the MCU32 in the following order in response to a control command: BMIC3_2(232), BMIC3_1(231), BMIC2_2(222), BMIC2_1(221), BMIC1_2(212), and BMIC1_1(211).

[0042] The MCU32 generates a control command and supplies a signal instructing the generated control command to the second winding 362 through two pins (P0, M0). The signal supplied to the second winding 362 is transmitted to the first winding 361 through an isolated link, and the signal transmitted to the first winding 361 is sent to the second winding 302. The signal sent to the second winding 302 is transmitted to the first winding 301, which is isolated from the second winding 302, and the signal from the voltage across the first winding 301 can be provided to the BMIC1_1(211) through two pins (P1, M1).

[0043] BMIC1_1(211) receives signals through two pins (P1, M1) and supplies them to the first winding 371 through two pins (P2, M2). The signals supplied to the first winding 371 are transmitted to the second winding 372 through an isolated link, and the signal from the voltage across the second winding 372 can be supplied to BMIC1_2(212) through two pins (P2, M2). BMIC1_2(212) receives signals through two pins (P2, M2) and supplies them to the first winding 311 through two pins (P1, M1). The signals supplied to the first winding 311 are transmitted to the second winding 312 through an isolated link, and the signals transmitted to the second winding 312 are transmitted to the second winding 322 of the double transformer 223 of BMS20_2. The signal transmitted to the second winding 322 is transmitted to the first winding 321 of the double transformer 223, which is insulated-linked to the second winding 322, and the signal from the voltage across the first winding 321 can be provided to BMIC2_1(221) through two pins (P1, M1) of BMIC2_1(221).

[0044] BMIC2_1(221) receives signals through two pins (P1, M1) and supplies them to the first winding 381 through two pins (P2, M2). The signals supplied to the first winding 381 are transmitted to the second winding 382 through an isolated link, and the signal from the voltage across the second winding 382 can be supplied to BMIC2_2(222) through two pins (P2, M2). BMIC2_2(222) receives signals through two pins (P2, M2) and supplies them to the first winding 331 through two pins (P1, M1). The signals supplied to the first winding 331 are transmitted to the second winding 332 through an isolated link, and the signals transmitted to the second winding 332 are transmitted to the second winding 342 of the double transformer 233 of BMS20_3. The signal transmitted to the second winding 342 is transmitted to the first winding 341 of the double transformer 233, which is insulated-linked to the second winding 342, and the signal from the voltage across the first winding 341 can be provided to BMIC3_1(231) through two pins (P1, M1) of BMIC3_1(231).

[0045] BMIC3_1(231) receives signals through two pins (P1, M1) and supplies them to the first winding 391 through two pins (P2, M2). The signals supplied to the first winding 391 are transmitted to the second winding 392 through an isolated link, and the signal from the voltage across the second winding 392 can be supplied to BMIC3_2(232) through two pins (P2, M2). All BMIC1_1(211), BMIC1_2(212), BMIC2_1(221), BMIC2_2(222), BMIC3_1(231), and BMIC3_2(232), upon receiving a signal instructing a control command, can perform monitoring operations in response to the control command and generate monitoring information. The monitoring information can be transmitted to the MCU32 in the order of BMIC3_2(232) to BMIC1_1(211) along the daisy-chain.

[0046] BMIC3_2(232) supplies a signal indicating monitoring information to the second winding 392 through two pins (P2, M2) of BMIC3_2(232). The signal supplied to the second winding 392 is transmitted to the first winding 391 through an isolated link, and the signal from the voltage across the first winding 391 can be provided to BMIC3_1(231) through two pins (P2, M2) of BMIC3_1(231). BMIC3_1(231) updates the monitoring information by adding the monitoring information it generated to the signal received from BMIC3_2(232), and supplies a signal indicating the updated monitoring information to the first winding 341 through two pins (P1, M1) of BMIC3_1(231). The signal supplied to the first winding 341 is transmitted to the second winding 342 through an isolated link, and the signal transmitted to the second winding 342 is sent to the second winding 332. The signal sent to the second winding 332 is transmitted to the first winding 331, which is isolated and linked to the second winding 332, and the signal from the voltage across the first winding 331 can be provided to BMIC2_2(222) through two pins (P1, M1) of BMIC2_2(222).

[0047] BMIC2_2(222) updates the monitoring information by adding the monitoring information it generates to the signal received from BMIC3_1(231), and supplies a signal indicating the updated monitoring information to the second winding 382 through two pins (P2, M2) of BMIC2_2(222). The signal supplied to the second winding 382 is transmitted to the first winding 381 through the isolated link, and the signal from the voltage across the first winding 381 can be provided to BMIC2_1(221) through two pins (P2, M2) of BMIC2_1(221). BMIC2_1(221) supplies a signal to the first winding 321 through two pins (P1, M1) of BMIC2_1(221) with the monitoring information it generates added to the signal received from BMIC2_2(222). The signal supplied to the first winding 321 is transmitted to the second winding 322 through an isolated link, and the signal transmitted to the second winding 322 is sent to the second winding 312. The signal sent to the second winding 312 is transmitted to the first winding 311, which is isolated and linked to the second winding 312, and the signal from the voltage across the first winding 311 can be provided to BMIC1_2(212) through two pins (P1, M1) of BMIC1_2(212).

[0048] BMIC1_2(212) supplies a signal to the second winding 372 through two pins (P2, M2) of BMIC1_2(212) that has been combined with monitoring information generated by BMIC1_2(212) to the signal received from BMIC2_1(221). The signal supplied to the second winding 372 is transmitted to the first winding 371 through an isolated link, and the signal from the voltage across the first winding 371 can be provided to BMIC1_1(211) through two pins (P2, M2) of BMIC1_1(211). BMIC1_1(211) supplies a signal to the first winding 301 through two pins (P1, M1) of BMIC1_1(211) that has been combined with monitoring information generated by BMIC1_1(211) to the signal received from BMIC1_2(212). The signal supplied to the first winding 301 is transmitted to the second winding 302 through an isolated link, and the signal transmitted to the second winding 302 is sent to the first winding 361. The signal sent to the first winding 361 is transmitted to the second winding 362, which is isolatedly linked to the first winding 361, and the signal, which is the voltage across the second winding 362, can be provided to the MCU 32 through two pins (P0, M0).

[0049] Thus, one embodiment allows signals to be transmitted and received between the rack BMS 30 and multiple BMSs 20_1, 20_2, and 20_3 using a daisy-chain method via a dual transformer. However, the present invention is not limited to this, and one embodiment allows signals to be transmitted and received between the rack BMS 30 and multiple BMSs 20_1, 20_2, and 20_3 using a multi-channel method via a dual transformer.

[0050] Figure 6 is a block diagram showing a battery system according to one embodiment.

[0051] The battery system 2 may include multiple battery packs 10_1 to 10_3, multiple BMS 60_1 to 60_3, a rack BMS 70, a switch device 40, and a current sensor 50. Of the components of the battery system 2 in this embodiment, those identical to those in the embodiment in Figure 1 are shown in Figure 6 with the same reference numerals.

[0052] Each of the multiple BMS60_1, 60_2, and 60_3 units is connected to correspond to each of the multiple battery packs 10_1 to 10_3, and can measure the cell voltage of each of the multiple battery cells (CE1 to CEn) of the corresponding battery pack and transmit the multiple cell voltages of each of the multiple battery cells (CE1 to CEn) of the multiple battery packs 10_1 to 10_3 to the rack BMS70 on multiple channels.

[0053] The rack BMS70 can transmit corresponding control commands through multiple channels corresponding to each of the multiple BMS60_1, 60_2, and 60_3 units. Each of the multiple BMS60_1, 60_2, and 60_3 units can perform actions in response to the received control commands and transmit monitoring information acquired by those actions to the rack BMS70.

[0054] Figure 6 shows that two channels are formed between each of the multiple BMS60_1, 60_2, and 60_3 units and the RBMS70. This is because each of the multiple BMS60_1, 60_2, and 60_3 units contains two BMICs. The number of channels can be determined according to the number of BMICs contained in each of the multiple BMS60_1, 60_2, and 60_3 units.

[0055] Figure 7 is a diagram showing a partial configuration of a battery system according to one embodiment.

[0056] Figure 7 shows a partial configuration of multiple BMS60_1, 60_2, 60_3 and a rack BMS70.

[0057] Each of the multiple BMS60_1, 60_2, and 60_3 can include two BMICs (611, 612, 621, 622, 631, 632) and dual transformers (213, 223, 233).

[0058] BMS60_1 may include two BMIC1_1~2 (611, 612) and a dual transformer 213. BMIC1_1 (611) is connected to half of the battery cells of the battery pack 10_1 and can measure the cell voltage of the connected battery cells. BMIC1_2 (612) is connected to the other half of the battery cells of the battery pack 10_1 and can measure the cell voltage of the connected battery cells. Each of BMIC1_1 (611) and BMIC1_2 (612) includes two pins (P1, M1). The two pins (P1, M1) of BMIC1_1 (611) are connected to both ends of the first winding 301 of the dual transformer 213, and the two pins (P1, M1) of BMIC1_2 (612) are connected to both ends of the third winding 311 of the dual transformer 213. The grounds (GND1, GND2) of the first winding 301 and the third winding 311 are isolated from each other. The ends of the second winding 302 of the double transformer 213 are connected to the first winding 711 of the transformer 71, and the ends of the second winding 712 of the transformer 71 are connected to the MCU 77 through two pins (P11, M11). The ends of the fourth winding 312 of the double transformer 213 are connected to the first winding 721 of the transformer 72, and the ends of the second winding 722 of the transformer 72 are connected to the MCU 77 through two pins (P12, M12).

[0059] The BMS60_2 may include two BMIC2_1~2 (621, 622) and a dual transformer 223. BMIC2_1 (621) is connected to half of the battery cells of the battery pack 10_2 and can measure the cell voltage of the connected battery cells. BMIC2_2 (622) is connected to the other half of the battery cells of the battery pack 10_2 and can measure the cell voltage of the connected battery cells. Each of BMIC2_1 (621) and BMIC2_2 (622) includes two pins (P1, M1). The two pins (P1, M1) of BMIC2_1 (621) are connected to both ends of the first winding 321 of the dual transformer 223, and the two pins (P1, M1) of BMIC2_2 (622) are connected to both ends of the third winding 331 of the dual transformer 223. The grounds (GND3, GND4) of the first winding 321 and the third winding 331 are isolated from each other. The ends of the second winding 322 of the double transformer 223 are connected to the first winding 731 of the transformer 73, and the ends of the second winding 732 of the transformer 73 are connected to the MCU 77 through two pins (P13, M13). The ends of the fourth winding 332 of the double transformer 223 are connected to the first winding 741 of the transformer 74, and the ends of the second winding 742 of the transformer 74 are connected to the MCU 77 through two pins (P14, M14).

[0060] The BMS60_3 may include two BMIC3_1~2 (631, 632) and a dual transformer 233. BMIC3_1 (631) is connected to half of the battery cells of the battery pack 10_3 and can measure the cell voltage of the connected battery cells. BMIC3_2 (632) is connected to the other half of the battery cells of the battery pack 10_3 and can measure the cell voltage of the connected battery cells. Each of BMIC3_1 (631) and BMIC3_2 (632) includes two pins (P1, M1). The two pins (P1, M1) of BMIC3_1 (631) are connected to both ends of the first winding 341 of the dual transformer 233, and the two pins (P1, M1) of BMIC3_2 (632) are connected to both ends of the third winding 351 of the dual transformer 233. The grounds (GND5, GND6) of the first winding 341 and the third winding 351 are isolated from each other. The ends of the second winding 342 of the double transformer 233 are connected to the first winding 751 of the transformer 75, and the ends of the second winding 752 of the transformer 75 are connected to the MCU 77 through two pins (P15, M15). The ends of the fourth winding 352 of the double transformer 233 are connected to the first winding 761 of the transformer 76, and the ends of the second winding 762 of the transformer 76 are connected to the MCU 77 through two pins (P16, M16).

[0061] The MCU77 sends control commands to each of the multiple BMICs (611, 612, 621, 622, 631, 632), each of the multiple BMICs (611, 612, 621, 622, 631, 632) performs monitoring operations in response to the control commands and generates monitoring information, and each of the multiple BMICs (611, 612, 621, 622, 631, 632) can send a signal to the MCU77 indicating the monitoring information it generated in response to the control command. The method of sending and receiving signals between the MCU77 and each of the multiple BMICs (611, 612, 621, 622, 631, 632) may be the same.

[0062] For example, MCU77 can send a control command to BMIC2_1(621) and receive monitoring information from BMIC2_1(621) in response to the control command. MCU77 generates a control command and supplies a signal instructing the generated control command to the second winding 732 through two pins (P13, M13). The signal supplied to the second winding 732 is transmitted to the first winding 731 through an isolated link, and the signal transmitted to the first winding 731 is sent to the second winding 322. The signal transmitted to the second winding 322 is transmitted to the first winding 321, which is isolated from the second winding 322, and the signal from the voltage across the first winding 321 can be provided to BMIC2_1(621) through two pins (P1, M1).

[0063] The BMIC2_1(621) performs monitoring operations in response to control commands to generate monitoring information and supplies a signal indicating the generated monitoring information to the first winding 321 through two pins (P1, M1) of the BMIC2_1(621). The signal supplied to the first winding 321 is transmitted to the second winding 322 through an isolated link, and the signal transmitted to the second winding 322 is transmitted to the first winding 731. The signal transmitted to the first winding 731 is transmitted to the second winding 732, which is isolated and linked to the first winding 731, and the signal from the voltage across the second winding 732 can be provided to the MCU77 through two pins (P13, M14).

[0064] Using the same method, it is possible to send and receive signals between the MCU77 and each of the multiple BMICs (611, 612, 621, 622, 631, 632).

[0065] Embodiments of this disclosure enable bidirectional communication using a dual transformer with an integrated structure and isolated ground instead of two single transformers. This allows for more space on the PCB for fabricating the BMS, thereby reducing manufacturing costs.

[0066] Although embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art, utilizing the basic concepts of the present invention as defined in the claims, also fall within the scope of the present invention.

Claims

1. Multiple battery packs containing multiple battery cells; Multiple battery management systems connected to the aforementioned multiple battery packs; and Includes a rack battery management system that transmits control commands to the plurality of battery management systems and receives a plurality of monitoring information in response to the control commands from the plurality of battery management systems, Each of the aforementioned battery management systems is: Two BMICs (Battery Management ICs) connected to a corresponding battery pack among the plurality of battery packs, which generate monitoring information for the corresponding battery pack in response to the control command, and The dual transformer includes a first winding connected to the first BMIC of the two BMICs, and a second winding connected to the second BMIC of the two BMICs, The ground of the first winding and the ground of the second winding are separated from each other. Battery system.

2. Of the aforementioned multiple battery management systems, the first dual transformer of the first battery management system is A third winding, insulated and linked to the first winding, and connected to the rack battery management system; and Further including a fourth winding which is insulatedly linked to the second winding and connected to the second battery management system among the plurality of battery management systems, The battery system according to claim 1.

3. The second battery management system is, A second double transformer including a fifth winding connected to the fourth winding and a sixth winding insulated and linked to the fifth winding; and Including a third BMIC connected to the sixth winding, The battery system according to claim 2.

4. The second battery management system is, The system further includes a fourth BMIC connected to a corresponding battery pack among the aforementioned plurality of battery packs, The second double transformer is, The system further includes a seventh winding connected to the fourth BMIC and an eighth winding insulated and linked to the seventh winding. The ground of the sixth winding and the ground of the seventh winding are separated from each other. Each of the third BMIC and the fourth BMIC is connected to half of the battery cells of the corresponding battery pack. The battery system according to claim 3.

5. The first battery management system is Further including a ninth winding and a tenth winding insulated and linked between the first BMIC and the second BMIC, The battery system according to claim 2.

6. The signal transmitted to the third winding is provided to the first BMIC via the first winding, the first BMIC transmits the signal to the second BMIC via the ninth and tenth windings, and the second BMIC transmits the signal to the second battery management system via the second and fourth windings. The battery system according to claim 5.

7. The signal transmitted to the third winding instructs the control command. The battery system according to claim 6.

8. A first signal transmitted from the second battery management system to the fourth winding is provided to the second BMIC via the second winding; the second BMIC transmits a second signal, which has monitoring information generated by the second BMIC added to the first signal, to the first BMIC via the ninth and tenth windings; and the first BMIC transmits a third signal, which has monitoring information generated by the first BMIC added to the second signal, to the rack battery management system via the first and third windings. The battery system according to claim 5.

9. The first signal includes monitoring information of the second battery management system. The battery system according to claim 8.

10. The second battery management system is, Third and fourth BMICs connected to the corresponding battery pack; A second double transformer including a fifth winding connected to the fourth winding, a sixth winding insulatedly linked to the fifth winding and connected to the third BMIC, a seventh winding connected to the fourth BMIC, and an eighth winding insulatedly linked to the seventh winding; and Including an eleventh winding and a twelfth winding insulated and linked between the third BMIC and the fourth BMIC, The ground of the sixth winding and the ground of the seventh winding are separated from each other. The battery system according to claim 5.

11. The signal transmitted to the fifth winding is provided to the third BMIC via the sixth winding, the third BMIC transmits the signal to the fourth BMIC via the eleventh and twelfth windings, and the fourth BMIC transmits the signal to the third battery management system among the plurality of battery management systems via the seventh and eighth windings. The battery system according to claim 10.

12. A first signal transmitted from the third battery management system to the eighth winding of the plurality of battery management systems is provided to the fourth BMIC via the seventh winding; the fourth BMIC transmits a second signal, which is the first signal with monitoring information generated by the fourth BMIC added to it, to the third BMIC via the eleventh and twelfth windings; and the third BMIC transmits a third signal, which is the second signal with monitoring information generated by the third BMIC added to it, to the first battery management system via the fifth and sixth windings. The battery system according to claim 10.

13. The first signal includes monitoring information of the third battery management system. The battery system according to claim 12.

14. Each of the dual transformers in the aforementioned multiple battery management systems is A third winding, insulated and linked to the first winding, and connected to the rack battery management system; and Further including a fourth winding that is insulatedly linked to the second winding and connected to the rack battery management system, The battery system according to claim 1.

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