Battery equipment and battery management systems for insulation resistance measurements

Abstract

The first insulation resistance monitoring circuit includes a first resistor connected between the positive terminal of the battery pack and the node, and is connected between the positive terminal of the battery pack and a ground end of the external device and has a first monitoring terminal. The second insulation resistance monitoring circuit is connected between the ground end and the negative terminal of the battery pack and has a second monitoring terminal. The voltage monitoring circuit is connected between the node and the negative terminal of the battery pack and has a third monitoring terminal. The processor measures the voltage of the battery pack based on the voltage of the third monitoring terminal, and measures a first insulation resistance formed between the positive terminal of the battery pack and the ground end and a second insulation resistance formed between the negative terminal of the battery pack and the ground end based on the voltage of the first monitoring terminal and the voltage of the second monitoring terminal.

Description

[Technical Field]

[0001] Cross-reference to related applications This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0002135, filed January 6, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery device and a battery management system for measuring insulation resistance. [Background technology]

[0003] Electric vehicles or hybrid vehicles are vehicles that are primarily powered by using a battery as a power source to drive a motor, and research into them is actively underway as an alternative to internal combustion vehicles that can solve pollution and energy problems. In addition, rechargeable batteries are used in a variety of external devices other than electric vehicles.

[0004] As demand for batteries with high output and large charging capacity increases, battery packs in which multiple battery cells are connected and battery management systems that manage the battery packs are being used. Maintaining an insulating state is important for devices that use such battery packs. If the insulating state of the battery pack is not maintained, leakage current may occur, causing various problems. Therefore, battery management systems use a circuit that measures the insulation resistance of the battery pack to prevent leakage current from occurring.

[0005] On the other hand, the battery management system also requires a circuit for monitoring the high voltage of the battery pack, and therefore the insulation resistance measurement circuit and the high voltage monitoring circuit may increase the unit cost of the battery management system. Summary of the Invention [Problem to be solved by the invention]

[0006] An embodiment of the present invention provides a battery device and battery management system that can integrate an insulation resistance measurement circuit and a high voltage monitoring circuit. [Means for solving the problem]

[0007] According to one embodiment of the present invention, a battery device connected to an external device may be provided. The battery device may include a battery pack, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a processor. The first resistor may be connected between a positive terminal of the battery pack and a node, and the second resistor may be connected between the node and a ground terminal of the external device. The third resistor and the fourth resistor may be connected between the ground terminal and a negative terminal of the battery pack, and the fifth resistor may be connected between the node and the negative terminal of the battery pack. The processor may measure the voltage of the battery pack based on the voltage of one terminal of the fifth resistor, and may measure a first insulation resistance formed between the positive terminal of the battery pack and the ground terminal and a second insulation resistance formed between the negative terminal of the battery pack and the ground terminal based on the voltage of one terminal of the second resistor and a voltage at a junction between the third resistor and the fourth resistor.

[0008] In one embodiment, the battery device may further include a DC voltage source connected between the ground terminal and the negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor.

[0009] In one embodiment, the battery device may further include a first switch and a sixth resistor connected between the node and the ground terminal on a path formed by the second resistor, a second switch connected between the ground terminal and a negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor, and a seventh resistor connected between the node and the negative terminal of the battery pack on a path formed by the fifth resistor.

[0010] In one embodiment, the battery device may further include a third switch coupled between the node and a negative terminal of the battery pack on a path formed by the fifth resistor and the seventh resistor.

[0011] In one embodiment, the processor may measure the voltage of the battery pack based on a voltage divided by the fifth resistor and the seventh resistor with the first switch and the second switch turned off, and may measure the first insulation resistor and the second insulation resistor based on the voltage of the battery pack, a voltage divided by the second resistor and the sixth resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

[0012] In one embodiment, the battery device may further include a first switch connected between the positive terminal of the battery pack and the node on a path formed by the first resistor, a sixth resistor connected between the node and the ground terminal on a path formed by the second resistor, a second switch connected between the ground terminal and the negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor, and a seventh resistor connected between the node and the negative terminal of the battery pack on a path formed by the fifth resistor.

[0013] In one embodiment, the battery device may further include a third switch coupled between the node and a negative terminal of the battery pack on a path formed by the fifth resistor and the seventh resistor.

[0014] In one embodiment, the processor may measure the voltage of the battery pack based on a voltage divided by the fifth resistor and the seventh resistor with the first switch turned on and the second switch turned off, and may measure the first insulation resistor and the second insulation resistor based on the voltage of the battery pack, a voltage divided by the second resistor and the sixth resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

[0015] In one embodiment, the battery device may further include a first switch connected between the node and the ground terminal on a path formed by the second resistor, and a second switch connected between the ground terminal and a negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor.

[0016] In one embodiment, the battery device may further include a third switch coupled between the node and the negative terminal of the battery pack on a path formed by the fifth resistor.

[0017] In one embodiment, the processor may measure the voltage of the battery pack based on a voltage divided by the first resistor and the fifth resistor with the first switch and the second switch turned off, and may measure the first insulation resistor and the second insulation resistor based on the voltage of the battery pack, a voltage divided by the first resistor and the second resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

[0018] According to another embodiment of the present invention, there may be provided a battery management system for a battery device including a battery pack connected to an external device. The battery management system may include a first insulation resistance monitoring circuit, a second insulation resistance monitoring circuit, a voltage monitoring circuit, and a processor. The first insulation resistance monitoring circuit may include a first monitoring terminal and a first resistor connected between the positive terminal of the battery pack and a node, and may be connected between the positive terminal of the battery pack and a ground terminal of the external device. The second insulation resistance monitoring circuit may include a second monitoring terminal and be connected between the ground terminal and a negative terminal of the battery pack. The voltage monitoring circuit may include a third monitoring terminal and be connected between the node and the negative terminal of the battery pack. The processor may measure the voltage of the battery pack based on the voltage of the third monitoring terminal, and may measure a first insulation resistance formed between the positive terminal of the battery pack and the ground terminal and a second insulation resistance formed between the negative terminal of the battery pack and the ground terminal based on the voltage of the first monitoring terminal and the voltage of the second monitoring terminal.

[0019] In one embodiment, the first insulation resistance monitoring circuit may include a first switch, a second resistor, and a third resistor connected between the node and the ground terminal, and the first monitoring terminal may be connected to a junction of the second resistor and the third resistor. The second insulation resistance monitoring circuit may include a DC voltage source, a second switch, a fourth resistor, and a fifth resistor connected between the ground terminal and a negative terminal of the battery pack, and the second monitoring terminal may be connected to a junction of the fourth resistor and the fifth resistor. The voltage monitoring circuit may include a sixth resistor and a seventh resistor connected between the node and the negative terminal of the battery pack, and the third monitoring terminal may be connected to a junction of the sixth resistor and the seventh resistor.

[0020] In one embodiment, the processor may measure the voltage of the battery pack based on the voltage of the third monitoring terminal with the first switch and the second switch turned off, and may measure the first insulation resistance and the second insulation resistance based on the voltage of the battery pack, the voltage of the first monitoring terminal with the first switch turned on and the second switch turned off, and the voltage of the second monitoring terminal with the first switch turned off and the second switch turned on.

[0021] In one embodiment, the first insulation resistance monitoring circuit may include a second resistor and a third resistor connected between the node and the ground terminal, and a first switch connected between the positive terminal of the battery pack and the node on a path formed by the first resistor, and the first monitoring terminal may be connected to a junction of the second resistor and the third resistor.The second insulation resistance monitoring circuit may include a DC voltage source connected between the ground terminal and the negative terminal of the battery pack, a second switch, a fourth resistor and a fifth resistor, and the second monitoring terminal may be connected to a junction of the fourth resistor and the fifth resistor.The voltage monitoring circuit may include a sixth resistor and a seventh resistor connected between the node and the negative terminal of the battery pack, and the third monitoring terminal may be connected to a junction of the sixth resistor and the seventh resistor.

[0022] In one embodiment, the processor may measure the voltage of the battery pack based on the voltage at the third monitoring terminal with the first switch on and the second switch off, and may measure the first insulation resistance and the second insulation resistance based on the voltage of the battery pack, the voltage at the first monitoring terminal with the first switch on and the second switch off, and the voltage at the second monitoring terminal with the first switch off and the second switch on.

[0023] In one embodiment, the first insulation resistance monitoring circuit may include a first switch and a second resistor connected between the node and the ground terminal, and the first monitoring terminal may be connected to a junction of the first resistor and the second resistor. The second insulation resistance monitoring circuit may include a DC voltage source, a second switch, a third resistor, and a fourth resistor connected between the ground terminal and a negative terminal of the battery pack, and the second monitoring terminal may be connected to a junction of the third resistor and the fourth resistor. The voltage monitoring circuit may include a fifth resistor connected between the node and the negative terminal of the battery pack, and the third monitoring terminal may be connected to a junction of the first resistor and the fifth resistor.

[0024] In one embodiment, the processor may measure the voltage of the battery pack based on the voltage of the third monitoring terminal with the first switch and the second switch turned off, and may measure the first insulation resistance and the second insulation resistance based on the voltage of the battery pack, the voltage of the first monitoring terminal with the first switch turned on and the second switch turned off, and the voltage of the second monitoring terminal with the first switch turned off and the second switch turned on. [Effects of the Invention]

[0025] According to one embodiment, the insulation resistance measurement circuitry and the high voltage monitoring circuitry can be integrated to reduce the unit cost of the battery management system. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a diagram illustrating an example of a battery device according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram illustrating an example of a battery device according to another embodiment of the present invention. [Figure 3] 3 is a diagram illustrating voltage measurement of a battery pack in the battery device shown in FIG. 2. FIG. [Figure 4] 3 is a diagram illustrating measurement of insulation resistance in the battery device shown in FIG. 2. FIG. [Figure 5] 3 is a diagram illustrating measurement of insulation resistance in the battery device shown in FIG. 2. FIG. [Figure 6] FIG. 10 is a diagram illustrating an example of a battery device according to still another embodiment of the present invention. [Figure 7] FIG. 10 is a diagram illustrating an example of a battery device according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present invention will now be described in detail with reference to the accompanying drawings so that those skilled in the art can easily understand and practice the present invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention in the drawings, parts that are not relevant to the description are omitted, and similar parts are designated by similar reference numerals throughout the specification.

[0028] When a component is said to be "connected" to another component, it should be understood that it may be directly connected to the other component, but there may be other components in between. Conversely, when a component is said to be "directly connected" to another component, it should be understood that there are no other components in between.

[0029] In the following description, expressions stated in the singular can be interpreted as singular or plural unless explicit expressions such as "one" or "single" are used.

[0030] In the flowcharts described with reference to the figures, the order of operations may be changed, operations may be combined, certain operations may be split, and certain operations may not be performed.

[0031] FIG. 1 is a diagram showing an example of a battery device according to an embodiment of the present invention.

[0032] Referring to FIG. 1 , the battery device 100 has a structure electrically connected to an external device via a positive link terminal DC+ and a negative link terminal DC-. When the external device is a load, the battery device 100 can operate as a power source to supply power to the load and discharge the power. When the external device is a charger, the battery device 100 is charged by receiving external power via the charger. In one embodiment, the external device operating as a load may be, for example, an electronic device, a vehicle, or an energy storage system (ESS), and the vehicle may be, for example, a vehicle such as an electric vehicle, a hybrid vehicle, or a smart mobility vehicle. In one embodiment, in the case of a vehicle, the positive link terminal DC+ and the negative link terminal DC- of the battery device 100 are connected to an inverter (not shown), and the battery device 100 may be connected to a motor of the vehicle operating as a load via the inverter.

[0033] The battery device 100 includes a battery pack 110 , main switches 121 and 122 , a monitoring circuit 130 and a processor 140 .

[0034] Battery pack 110 has a positive terminal PV+ and a negative terminal PV-. Battery pack 110 may include a plurality of battery cells connected in series between the positive terminal PV+ and the negative terminal PV-. In one embodiment, the negative terminal PV- of battery pack 110 may be connected to the ground terminal of the battery device. In one embodiment, battery pack 110 may include a plurality of battery modules connected in series between the positive terminal PV+ and the negative terminal PV-, and each battery module may include a plurality of battery cells connected in series. In one embodiment, the battery cells may be rechargeable secondary batteries.

[0035] The main switches 121 and 122 include a positive main switch 121 connected between a positive terminal PV+ of the battery pack 110 and a positive link terminal DC+ of the battery device 100, and a negative main switch 122 connected between a negative terminal PV- of the battery pack 110 and a negative link terminal DC- of the battery device 100. The main switches 121 and 122 are controlled by the processor 140 to control the electrical connection between the battery pack 110 and the external device 10. In one embodiment, the main switches 121 and 122 each include a contactor including a relay. In one embodiment, the main switches 121 and 122 each include an electrical switch such as a transistor. In one embodiment, the battery device 100 may further include a drive circuit (not shown) that drives the main switches 121 and 122 in response to a control signal from the processor 140. When the positive main switch 121 and the negative main switch 122 are closed, power can be supplied from the battery pack 110 to an external device or power can be supplied from an external device to the battery pack 110. Closing the switch can be expressed as turning the switch on, and opening the switch can be expressed as turning the switch off.

[0036] An insulation resistance R of the battery device 100 is provided between the positive terminal PV+ of the battery pack 110 and the ground terminal of the external device 10. PI1 is formed between the negative terminal PV− of the battery pack 110 and the ground terminal of the external device 10, and an insulation resistance R NI1 In addition, an insulation resistance R of the external device 10 is formed between the positive link terminal DC+ of the battery pack 110 and the ground terminal of the external device 10. PI2 is formed, and an insulation resistance R of the external device 10 is formed between the negative link terminal DC− of the battery pack 110 and the ground terminal of the external device 10. NI2 The ground terminal of the external device 10 may be, for example, the chassis of a vehicle.

[0037] The monitoring circuit 130 is connected to the positive terminal PV+ and the negative terminal PV- of the battery pack 110 and the ground terminal of the external device 10, and monitors the voltage and insulation resistance R of the battery pack 110.PI1, R NI1, R PI2 ,R PI2 Monitor the following.

[0038] The processor 140 controls the monitoring circuit 130 and measures the voltage and insulation resistance R of the battery pack 110 based on information from the monitoring circuit 130. PI1, R NI1, R PI2 ,R PI2 The processor 140 also controls the operation of the main switches 121 and 122. In one embodiment, the processor 140 may be, for example, a microcontroller unit (MCU).

[0039] In one embodiment, the monitoring circuit 130 and the processor 140 can form a battery management system.

[0040] Next, monitoring circuits according to various embodiments will be described with reference to FIGS.

[0041] FIG. 2 is a diagram showing an example of a battery device according to another embodiment of the present invention, FIG. 3 is a diagram explaining voltage measurement of a battery pack in the battery device shown in FIG. 2, and FIGS. 4 and 5 are diagrams each explaining insulation resistance measurement in the battery device shown in FIG. 2.

[0042] 2, the battery device 200 includes a battery pack 210, main switches 221 and 222, a monitoring circuit 230, and a processor 240. The battery pack 210, main switches 221 and 222, and processor 240 are similar to the battery pack 110, main switches 121 and 122, and processor 140 described with reference to FIG. 1, and therefore, description thereof will be omitted.

[0043] The monitoring circuit 230 includes a first insulation resistance monitoring circuit 231 , a second insulation resistance monitoring circuit 232 and a voltage monitoring circuit 233 .

[0044] The first insulation resistance monitoring circuit 231 includes a resistor (or first resistor) R1 connected between the positive terminal PV+ of the battery pack 210 and a node N1, a switch (or first switch) SW1 and resistors (or second and sixth resistors or second and third resistors) R2 and R3 connected in series between the node N1 and the ground terminal of the external device, and has a first insulation resistance monitoring terminal (or first monitoring terminal) TR1 on a path formed by the resistors R2 and R3 and the switch SW1. The first insulation resistance monitoring terminal TR1 may be connected to one terminal of the resistor R2 or one terminal of the resistor R3. In one embodiment, a first terminal of the switch SW1 is connected to the node N1, and the resistor R2 is connected to the switch SW1. SW1 and a monitoring terminal TR1, and a resistor R3 may be connected between the monitoring terminal TR1 and the ground terminal.

[0045] In one embodiment, the connection order of switch SW1 and resistors R2 and R3 between node N1 and ground may be changed, in which case a node (e.g., a junction of resistors R2 and R3) at which a voltage divided by resistors R2 and R3 is output may be set as monitoring terminal TR1.

[0046] The second insulation resistance monitoring circuit 232 includes resistors (or third and fourth resistors or fourth and fifth resistors) R4 and R5 and a switch (or second switch) SW2 connected in series between the ground terminal of the external device and the negative terminal PV− of the battery pack 210, and has a second insulation resistance monitoring terminal (or second monitoring terminal) TR2 on a path formed by the resistors R4 and R5 and the switch SW2. The second insulation resistance monitoring terminal TR2 may be connected to one terminal of the resistor R4 or one terminal of the resistor R5. In one embodiment, the resistor R4 may be connected between the ground terminal and the monitoring terminal TR2, a first terminal of the switch SW2 may be connected to the monitoring terminal TR2, and the resistor R5 may be connected between the second terminal of the switch SW2 and the negative terminal PV− of the battery pack 210.

[0047] In one embodiment, the second insulation resistance monitoring circuit 232 connects the DC voltage source V to the path formed by resistors R4, R5 and switch SW2.DC The resistors R4 and R5 are connected between the negative terminal PV− of the battery pack 210 and the ground terminal, and therefore, the DC voltage source V is connected to the negative terminal PV− of the battery pack 210 so that the voltage of the second insulation resistance monitoring terminal TR2 becomes a positive voltage. DC In one embodiment, a DC voltage source V DC The negative terminal of is connected to the ground terminal, and the DC voltage source V DC The positive terminal of the resistor R4 may be connected to one terminal of the resistor R4.

[0048] In one embodiment, a DC voltage source V is connected between the ground terminal and the negative terminal PV− of the battery pack 210. DC The connection order of the resistors R4 and R5 and the switch SW2 can be changed. In this case, the node (for example, the junction of the resistors R4 and R5) at which the voltage divided by the resistors R4 and R5 is output can be set as the monitoring terminal TR2.

[0049] The voltage monitoring circuit 233 includes a switch (or a third switch) SW3 and resistors (or fifth and seventh resistors or sixth and seventh resistors) R6 and R7 connected in series between a node N1 in the first insulation resistance monitoring circuit 231 and the negative terminal PV− of the battery pack 210, and has a voltage monitoring terminal (or a third monitoring terminal) TV on a path formed by the switch SW3 and the resistors R6 and R7. The voltage monitoring terminal TV may be connected to one terminal of the resistor R6 or one terminal of the resistor R7. In one embodiment, a first terminal of the switch SW3 may be connected to the node N1 of the first insulation resistance monitoring circuit 231, the resistor R6 may be connected between the second terminal of the switch SW3 and the voltage monitoring terminal TV, and the resistor R7 may be connected between the voltage monitoring terminal TV and the negative terminal PV− of the battery pack 210.

[0050] In one embodiment, the connection order of the switch SW3 and the resistors R6 and R7 can be changed between the node N1 and the negative terminal PV− of the battery pack 210. In this case, a node (e.g., a junction of the resistors R6 and R7) at which the voltage divided by the resistors R6 and R7 is output can be set as the monitoring terminal TV.

[0051] The processor 240 controls the operation of the switches SW1, SW2, and SW3, measures the voltage of the battery pack 210 based on the voltage of the voltage monitoring terminal TV, and calculates the insulation resistance R based on the voltage of the battery pack 210, the voltage of the first insulation resistance monitoring terminal TR1, and the voltage of the second insulation resistance monitoring terminal TR2. PI1 ,R PI2 can be measured.

[0052] In one embodiment, the battery device 200 may further include an analog-to-digital converter that converts the voltage at the first insulation resistance monitoring terminal TR1 into a digital signal and transmits the digital signal to the processor 240, an analog-to-digital converter that converts the voltage at the second insulation resistance monitoring terminal TR2 into a digital signal and transmits the digital signal to the processor 240, and an analog-to-digital converter that converts the voltage at the voltage monitoring terminal TV into a digital signal and transmits the digital signal to the processor 240.

[0053] Next, a method for measuring the insulation resistance and the battery pack voltage in the battery device shown in FIG. 2 will be described.

[0054] First, the battery pack voltage measurement will be described with reference to FIG.

[0055] The processor 240 turns on the switch SW3 while keeping the switches SW1 and SW2 off. Then, as shown in Fig. 3, a current path is formed by the resistors R1, R6, and R7 between the positive terminal PV+ of the battery pack 210 and the negative terminal PV- of the battery pack 210. Also, because the switches SW1 and SW2 are off, no current path is formed between the node N1 and the ground terminal of the external device, and between the ground terminal and the negative terminal PV- of the battery pack 210. Therefore, as shown in equation (1), the voltage V of the battery pack 210 PACK is divided by resistors R1, R6, and R7, and the voltage V at the voltage monitoring terminal TV P The processor 240 outputs the voltage V at the voltage monitoring terminal TV. P Based on the voltage V of the battery pack 210 PACKcan be measured.

[0056]

number

[0057] In equation (1), R1, R6, and R7 are the resistance values ​​of the resistors R1, R6, and R7, respectively.

[0058] Next, insulation resistance measurement will be described with reference to FIGS.

[0059] 4, the processor 240 turns on the switch SW1 with the switch SW2 turned off and the switch SW3 turned on. In one embodiment, the processor 240 may turn off the switch SW3. When the switch SW1 is turned on, a current path is formed by the resistors R1, R2, and R3 between the positive terminal PV+ of the battery pack 210 and the ground terminal of the external device. Also, since the switch SW2 is turned off, a current path is not formed by the resistors R4 and R5. In this case, the insulation resistor R PI1 Therefore, a set of resistors R1, R2, and R3 and an insulation resistor R are provided between the positive terminal PV+ of the battery pack 210 and the ground terminal of the external device. PI1 In addition, an insulation resistance R is provided between the ground terminal and the negative terminal PV- of the battery pack 210. NI1 In this state, the processor 240 receives the voltage V1 of the first insulation resistance monitoring terminal TR1. PACK and the voltage V1 at the first insulation resistance monitoring terminal TR1 is determined by equation 2. When switch SW3 is turned on, a current path is formed through resistors R6 and R7, but for convenience of explanation, equation 2 assumes that the resistance values ​​of resistors R6 and R7 are large and therefore the current through resistors R6 and R7 can be ignored.

[0060]

number

[0061] In equation (2), R1, R2, R3, R PI1 and R NI1 are resistors R1, R2, R3, and R PI1 ,R NI1 is the resistance value.

[0062] 5, the processor 240 turns on the switch SW2 while the switch SW1 is turned off and the switch SW3 is turned on. In one embodiment, the processor 240 may turn off the switch SW3. By turning on the switch SW2, a voltage source V is applied between the ground terminal of the external device and the negative terminal PV− of the battery pack 210. DC A current path is formed by the resistors R1, R2, and R3. In addition, since the switch SW1 is turned off, a current path is not formed by the resistors R1, R2, and R3. In this case, an insulation resistor R is provided between the ground terminal and the negative terminal PV- of the battery pack 210. NI1 Therefore, a set of resistors R4 and R5 and an insulation resistor R are provided between the ground terminal and the negative terminal PV- of the battery pack 210. NI1 In addition, an insulation resistor R is provided between the positive terminal PV+ of the battery pack 210 and the ground terminal of the external device. PI1 In this state, the processor 240 receives the voltage V2 of the second insulation resistance monitoring terminal TR2. PACK and the voltage V2 at the second insulation resistance monitoring terminal TR2 can be determined by equation 3. When switch SW3 is turned on, a current path is formed through resistors R6 and R7, but for convenience of explanation, equation 3 assumes that the resistance values ​​of resistors R6 and R7 are large and therefore the current through resistors R6 and R7 can be ignored.

[0063]

number

[0064] In equation (3), R4, R5, RPI1 and R NI1 are resistors R4, R5, and R PI1 ,R NI1 is the resistance value.

[0065] The processor 240 monitors the voltage V1 at the first insulation resistance monitoring terminal TR1, the voltage V2 at the second insulation resistance monitoring terminal TR2, and the voltage V PACK Based on the insulation resistance R PI1 ,R NI1 The processor 240 calculates the resistance value of the insulation resistance R based on the equations (2) and (3). PI1 ,R NI1 The resistance values ​​of these can be calculated using equations (4) and (5), respectively.

[0066]

number

[0067]

number

[0068]

number

[0069]

number

[0070]

number

[0071]

number

[0072] On the other hand, when the main switches 221 and 222 are turned on, the insulation resistance R PI1 the insulation resistance R of the external device PI2 are connected in parallel, and the insulation resistance R NI1 the insulation resistance R of the external device NI2 Therefore, the processor 240 calculates the insulation resistances R connected in parallel according to the process described with reference to Equations (2) to (9). PI1 ,R PI2 The resistance of the insulation resistance R NI1 ,R NI2 The processor 240 can calculate the resistance value of the insulation resistance R measured when the main switches 221 and 222 are turned off. PI1 ,R NI1 and the insulation resistance R measured when the main switches 221 and 222 are turned on. PI1 / / R PI2 ,R NI1 / / R NI2 Based on the resistance value of the external device's insulation resistance R PI2 ,R NI2 The resistance value can be calculated.

[0073] According to the embodiment described above, the insulation resistance monitoring circuits 231, 232 and the voltage monitoring circuit 233 share the resistor R1, thereby reducing the unit cost of the battery management system compared to when the insulation resistance monitoring circuits 231, 232 and the voltage monitoring circuit 233 have separate resistors connected to the positive terminal PV+ of the battery pack 210.

[0074] FIG. 6 is a diagram showing an example of a battery device according to still another embodiment of the present invention.

[0075] 6, a battery device 600 includes a battery pack 610, main switches 621 and 622, a monitoring circuit 630, and a processor 640. The battery pack 610, main switches 621 and 622, and processor 640 are similar to the battery pack 110, main switches 121 and 122, and processor 140 described with reference to FIG. 1, and therefore their description will be omitted. The monitoring circuit 630 includes a first insulation resistance monitoring circuit 631, a second insulation resistance monitoring circuit 632, and a voltage monitoring circuit 633. The monitoring circuit 630 is similar to the monitoring circuit 230 described with reference to FIG. 2, and therefore differences will be described below.

[0076] A node N2 in the first insulation resistance monitoring circuit 631 to which the voltage monitoring circuit 633 is connected may be the junction of the switch SW1 and the resistor R2. That is, in the voltage monitoring circuit 633, the switch SW3 may be connected to the second terminal N2 of the switch SW1 in the first insulation resistance monitoring circuit 631. In one embodiment, the first terminal of the switch SW3 may be connected to the second terminal N2 of the switch SW1, and the resistor R6 may be connected between the second terminal of the switch SW3 and the voltage monitoring terminal TV.

[0077] In this case, to measure the voltage of the battery pack 610, the processor 640 turns on the switches SW1 and SW3 while keeping the switch SW2 off. By turning on the switches SW1 and SW3, a current path is formed by the resistors R1, R2, and R3 between the positive terminal PV+ of the battery pack 610 and the ground terminal of the external device. PI1 ,R NI1 ,R PI2 ,R NI2 For the measurement of , processor 640 performs the same operations as processor 240 shown in FIG.

[0078] FIG. 7 is a diagram showing an example of a battery device according to still another embodiment of the present invention.

[0079] 7, a battery device 700 includes a battery pack 710, main switches 721 and 722, a monitoring circuit 730, and a processor 740. The battery pack 710, main switches 721 and 722, and processor 740 are similar to the battery pack 110, main switches 121 and 122, and processor 140 described with reference to FIG. 1, and therefore their description will be omitted. The monitoring circuit 730 includes a first insulation resistance monitoring circuit 731, a second insulation resistance monitoring circuit 732, and a voltage monitoring circuit 733.

[0080] The monitoring circuit 730 is similar to the monitoring circuit 230 described with reference to FIG. 2, so the differences will be described.

[0081] In the first insulation resistance monitoring circuit 731, switch SW1 is connected between resistor R2 and resistor (or second resistor) R3, and a node N3 in the first insulation resistance monitoring circuit 731 to which the voltage monitoring circuit 733 is connected may be the junction of resistor R2 and switch SW1. In one embodiment, resistor R2 may be connected between one terminal of resistor R1 and node N3, switch SW1 may be connected between node N3 and first insulation resistance monitoring terminal TR1, and resistor R3 may be connected between first insulation resistance monitoring terminal TR1 and the ground terminal of the external device. In the voltage monitoring circuit 733, switch SW3 may be connected to node N3. In one embodiment, the voltage monitoring circuit 733 does not include resistor R6, and switch SW3 may be connected between node N3 and voltage monitoring terminal TV. In another embodiment, resistors R1 and R2 in the first insulation resistance monitoring circuit 731 may be replaced by a single resistor.

[0082] In this case, processor 740 performs the same operations as processor 240 shown in FIG. 2 for measuring the voltage and insulation resistance of battery pack 710.

[0083] In one embodiment, the unit cost of the battery management system can be further reduced by eliminating switch SW3 of the voltage monitoring circuit (233, 633, or 733) in the circuits shown in Figures 2, 6, and 7. In one embodiment, a resistor with a large resistance value can be used in the voltage monitoring circuit (233, 633, or 733). If switch SW3 is eliminated, leakage current may occur due to the resistance of the voltage monitoring circuit (233, 633, or 733), but by using a resistor with a large resistance value, the leakage current can be ignored.

[0084] Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

Claims

1. A battery device coupled to an external device, A battery pack; a first resistor connected between the positive terminal of the battery pack and a node; a second resistor connected between the node and a ground terminal of the external device; a third resistor and a fourth resistor connected between the ground terminal and a negative terminal of the battery pack; a fifth resistor connected between the node and a negative terminal of the battery pack; a processor that measures a voltage of the battery pack based on a voltage at one terminal of the fifth resistor, and that measures a first insulation resistance formed between the positive terminal of the battery pack and the ground end and a second insulation resistance formed between the negative terminal of the battery pack and the ground end based on a voltage at one terminal of the second resistor and a voltage at a junction between the third resistor and the fourth resistor.

2. The battery device according to claim 1 , further comprising a DC voltage source connected between the ground terminal and a negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor.

3. a first switch and a sixth resistor connected between the node and the ground terminal on a path formed by the second resistor; a second switch connected between the ground terminal and the negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor; 3. The battery device according to claim 1, further comprising a seventh resistor connected between the node and a negative terminal of the battery pack on the path formed by the fifth resistor.

4. The battery device according to claim 3 , further comprising a third switch coupled between the node and a negative terminal of the battery pack on a path formed by the fifth resistor and the seventh resistor.

5. The processor: measuring a voltage of the battery pack based on a voltage divided by the fifth resistor and the seventh resistor while the first switch and the second switch are turned off; 4. The battery device according to claim 3, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage divided by the second resistor and the sixth resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

6. a first switch connected between the positive terminal of the battery pack and the node on a path formed by the first resistor; a sixth resistor connected between the node and the ground terminal on the path formed by the second resistor; a second switch connected between the ground terminal and the negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor; 3. The battery device according to claim 1, further comprising: a seventh resistor connected between the node and a negative terminal of the battery pack on a path formed by the fifth resistor.

7. The battery device according to claim 6 , further comprising a third switch coupled between the node and a negative terminal of the battery pack on a path formed by the fifth resistor and the seventh resistor.

8. The processor: measuring a voltage of the battery pack based on a voltage divided by the fifth resistor and the seventh resistor while turning on the first switch and turning off the second switch; 7. The battery device according to claim 6, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage divided by the second resistor and the sixth resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

9. a first switch connected between the node and the ground terminal on a path formed by the second resistor; 3. The battery device according to claim 1, further comprising: a second switch connected between the ground terminal and a negative terminal of the battery pack on a path formed by the third resistor and the fourth resistor.

10. 10. The battery device according to claim 9, further comprising a third switch coupled between the node and a negative terminal of the battery pack on a path formed by the fifth resistor.

11. The processor: measuring a voltage of the battery pack based on a voltage divided by the first resistor and the fifth resistor while the first switch and the second switch are turned off; 10. The battery device according to claim 9, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage divided by the first resistor and the second resistor with the first switch turned on and the second switch turned off, and a voltage divided by the third resistor and the fourth resistor with the first switch turned off and the second switch turned on.

12. A battery management system for a battery device including a battery pack connected to an external device, a first insulation resistance monitoring circuit including a first monitoring terminal and a first resistor connected between a positive terminal of the battery pack and a node, the first insulation resistance monitoring circuit being connected between the positive terminal of the battery pack and a ground terminal of the external device; a second insulation resistance monitoring circuit including a second monitoring terminal connected between the ground terminal and the negative terminal of the battery pack; a voltage monitoring circuit including a third monitoring terminal, the voltage monitoring circuit being coupled between the node and the negative terminal of the battery pack; a processor that measures a voltage of the battery pack based on a voltage of the third monitoring terminal, and measures a first insulation resistance formed between a positive terminal of the battery pack and the ground end and a second insulation resistance formed between a negative terminal of the battery pack and the ground end based on the voltage of the first monitoring terminal and the voltage of the second monitoring terminal.

13. the first insulation resistance monitoring circuit further includes a first switch, a second resistor, and a third resistor connected between the node and the ground terminal, the first monitoring terminal being connected to a junction between the second resistor and the third resistor; the second insulation resistance monitoring circuit further includes a DC voltage source connected between the ground terminal and a negative terminal of the battery pack, a second switch, a fourth resistor, and a fifth resistor, the second monitoring terminal being connected to a junction between the fourth resistor and the fifth resistor; 13. The battery management system of claim 12, wherein the voltage monitoring circuit further includes a sixth resistor and a seventh resistor coupled between the node and a negative terminal of the battery pack, and the third monitoring terminal is coupled to a junction of the sixth resistor and the seventh resistor.

14. The processor: measuring a voltage of the battery pack based on a voltage of the third monitoring terminal while the first switch and the second switch are turned off; 14. The battery management system according to claim 13, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage at the first monitoring terminal with the first switch turned on and the second switch turned off, and a voltage at the second monitoring terminal with the first switch turned off and the second switch turned on.

15. the first insulation resistance monitoring circuit further includes a second resistor and a third resistor connected between the node and the ground terminal, and a first switch connected between a positive terminal of the battery pack and the node on a path formed by the first resistor, the first monitoring terminal being connected to a junction between the second resistor and the third resistor; the second insulation resistance monitoring circuit further includes a DC voltage source connected between the ground terminal and a negative terminal of the battery pack, a second switch, a fourth resistor, and a fifth resistor, the second monitoring terminal being connected to a junction between the fourth resistor and the fifth resistor; 13. The battery management system of claim 12, wherein the voltage monitoring circuit further includes a sixth resistor and a seventh resistor coupled between the node and a negative terminal of the battery pack, and the third monitoring terminal is coupled to a junction of the sixth resistor and the seventh resistor.

16. The processor: measuring a voltage of the battery pack based on a voltage of the third monitoring terminal while the first switch is turned on and the second switch is turned off; 16. The battery management system according to claim 15, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage at the first monitoring terminal in a state where the first switch is turned on and the second switch is turned off, and a voltage at the second monitoring terminal in a state where the first switch is turned off and the second switch is turned on.

17. the first insulation resistance monitoring circuit further includes a first switch and a second resistor connected between the node and the ground terminal, the first monitoring terminal being connected to a junction between the first resistor and the second resistor; the second insulation resistance monitoring circuit further includes a DC voltage source connected between the ground terminal and a negative terminal of the battery pack, a second switch, a third resistor, and a fourth resistor, the second monitoring terminal being connected to a junction between the third resistor and the fourth resistor; 13. The battery management system of claim 12, wherein the voltage monitoring circuit further includes a fifth resistor coupled between the node and a negative terminal of the battery pack, and the third monitoring terminal is coupled to a junction of the first resistor and the fifth resistor.

18. The processor: measuring a voltage of the battery pack based on a voltage of the third monitoring terminal while the first switch and the second switch are turned off; 18. The battery management system according to claim 17, wherein the first insulation resistance and the second insulation resistance are measured based on a voltage of the battery pack, a voltage at the first monitoring terminal in a state where the first switch is turned on and the second switch is turned off, and a voltage at the second monitoring terminal in a state where the first switch is turned off and the second switch is turned on.

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