CN112858856A - Low-cost insulation detection circuit and detection method - Google Patents
Low-cost insulation detection circuit and detection method Download PDFInfo
- Publication number
- CN112858856A CN112858856A CN202110240694.6A CN202110240694A CN112858856A CN 112858856 A CN112858856 A CN 112858856A CN 202110240694 A CN202110240694 A CN 202110240694A CN 112858856 A CN112858856 A CN 112858856A
- Authority
- CN
- China
- Prior art keywords
- resistor
- insulation
- switch
- voltage
- low
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention discloses a low-cost insulation detection circuit and a detection method, wherein the method is applied to the low-cost insulation detection circuit, and the circuit comprises an insulation resistor RP, an insulation resistor RN, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a switch K1, a switch K2 and a battery management system; the insulation resistance RP is insulation resistance of a positive electrode of an external battery pack to the ground, the insulation resistance RN is insulation resistance of a negative electrode of the external battery pack to the ground, and the battery management system detects insulation impedance of the insulation resistance RP and the insulation resistance RN by controlling on and off of the switch K1 and the switch K2. According to the low-cost insulation detection circuit and the detection method, the traditional resistance voltage division measurement method is optimized, insulation resistance detection can be carried out only by two switches, the performance is not attenuated, the circuit structure is simplified, the ultralow cost advantage is achieved, and the risk of electric shock of people during operation can be further effectively reduced.
Description
Technical Field
The invention relates to the technical field of batteries of electric vehicles and energy storage battery systems, in particular to a low-cost insulation detection circuit and a low-cost insulation detection method.
Background
With the vigorous development of electric automobiles in the field of new energy, the electric automobiles are more and more widely applied. Compared with the conventional vehicle, the electric vehicle has a whole set of high-voltage components (ESS-Energy Storage System, DCDC-DC-DC converter, motor and the like), and the higher working voltage puts higher requirements on the insulation performance between the high-voltage System and the vehicle chassis. Therefore, in view of safety, it is necessary to increase the detection of the insulation state, and particularly, when a vehicle collides in a complicated application environment and parts are degraded, the insulation performance may be lowered to increase the chassis potential, which may not only affect the operation of the vehicle-mounted device and an ECU (Electronic Control Unit), but also cause the heat accumulation effect of the leakage circuit to cause the vehicle to ignite and burn. The power Battery system ESS is a source of high voltage, and therefore insulation detection is also one of the key functions of the BMS (Battery management system).
Currently, there are two general insulation detection methods in the market: one is signal injection and the other is resistance voltage division measurement. The signal injection method is to inject a direct current voltage signal with a certain frequency into the battery system, measure the fed back direct current signal and calculate the insulation resistance, but the injected signal will generate ripple interference to the battery system and influence the normal work of the system. In the traditional resistance voltage division measurement method, 3 or more than 3 switches are required to be introduced to switch a measurement loop, and insulation resistance is derived by measuring the voltage on the voltage division resistance under different conditions, so that the structure of the circuit is complex and the cost is high.
Disclosure of Invention
The invention mainly aims to provide a low-cost insulation detection circuit and a low-cost insulation detection method, and aims to solve the technical problems that when a traditional resistance voltage division measurement method is used for detecting an insulation resistance in the prior art, the structure of the circuit is complex and the cost is high.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a low-cost insulation detection circuit comprises an insulation resistor RP, an insulation resistor RN, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a switch K1, a switch K2 and a battery management system; one end of the insulation resistor RP is connected to the positive electrode of an external battery pack and one end of the resistor R1, the other end of the insulation resistor RP is grounded, one end of the insulation resistor RN is connected to the negative electrode of the external battery pack and one end of the resistor R4, the other end of the insulation resistor RN is grounded, the other end of the resistor R1 is connected to one end of the resistor R2 and one end of the switch K1, the other end of the switch K1 is grounded, the other end of the resistor R2 is connected to one end of the resistor R3 and one end of the switch K2, the other end of the switch K2 is grounded, and the other end of the resistor R3 is connected to the other end of the resistor R4 and the battery management system; the insulation resistance RP is an insulation resistance of a positive electrode of an external battery pack to the ground, the insulation resistance RN is an insulation resistance of a negative electrode of the external battery pack to the ground, and the battery management system detects insulation impedances of the insulation resistance RP and the insulation resistance RN by controlling on and off of the switch K1 and the switch K2.
Preferably, the battery pack is applied to a battery high-voltage system or an energy storage battery high-voltage system of an electric vehicle.
Preferably, when the battery pack is applied to a battery high-voltage system of an electric vehicle, the insulation resistance RP represents the insulation resistance of the high voltage of the positive bus of the battery pack to the chassis of the electric vehicle, and the insulation resistance RN represents the insulation resistance of the high voltage of the negative bus of the battery pack to the chassis of the electric vehicle;
when the battery pack is applied to an energy storage battery high-voltage system, the insulation resistance RP represents the insulation resistance of the high voltage of the positive bus of the battery pack to the ground of the energy storage system, and the insulation resistance RN represents the insulation resistance of the high voltage of the negative bus of the battery pack to the ground of the energy storage system.
The other technical scheme provided by the invention is as follows:
a low-cost insulation detection method is applied to the low-cost insulation detection circuit and comprises the following steps:
s1: the battery management system sends a command, disconnects the switch K1 and the switch K2, and collects voltage V0 through an analog-to-digital converter;
s2: the battery management system sends a command, closes the switch K1, opens the switch K2 and collects voltage V1 through an analog-to-digital converter;
s3: the battery management system sends a command, opens the switch K1 and closes the switch K2, and acquires a voltage V2 through an analog-to-digital converter;
s4: calculating the insulation resistance of the insulation resistance RP and the insulation resistance RN by combining the voltage V0, the voltage V1 and the voltage V2;
wherein the battery management system is connected with the other end of the resistor R4 through the analog-to-digital converter.
Preferably, the total battery pressure Vbat is calculated by the voltage V0, and the calculation formula is specifically:
wherein R1, R2, R3 and R4 are resistances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively.
Preferably, the calculation formula of the voltage V1 is specifically:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
Preferably, the calculation formula of the voltage V2 is specifically:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
Preferably, after S4, the method further includes:
s5: and when the insulation impedance of the insulation resistor RP meets a preset first alarm condition and/or the insulation impedance of the insulation resistor RN meets a preset second alarm condition, sending an alarm signal.
Preferably, when the switch K1 is closed and the switch K2 is opened, the voltage to the ground at the switch K1 is Vm1, and the calculation formula is specifically as follows:
wherein, R2, R3 and R4 are impedances of the resistor R2, the resistor R3 and the resistor R4, I1 is a current flowing through a total resistance of the circuit loop, and Rn is an insulation impedance of the insulation resistor Rn.
Preferably, when the switch K1 is opened and the switch K2 is closed, the voltage to the ground at the switch K2 is Vm2, and the calculation formula is specifically as follows:
wherein, R3 and R4 are the impedances of the resistor R3 and the resistor R4, respectively, I2 is the current flowing through the total resistance of the circuit loop, and Rn is the insulation impedance of the insulation resistor Rn.
Compared with the prior art, the invention has the following beneficial effects:
in this application, optimize traditional resistance partial pressure measurement method, only need two switches just to carry out insulation resistance and detect, and the performance does not have the decay, and circuit structure simplifies, has ultralow cost advantage, can further effectively reduce the risk that people electrocute when the operation, improves the operation security.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a schematic circuit diagram of a low cost insulation detection circuit according to a first embodiment of the present invention;
FIG. 2 is a flow chart of a low-cost insulation detection method according to a second embodiment of the present invention;
fig. 3 is a circuit configuration diagram of the low-cost insulation detection circuit according to the second embodiment of the present invention in a state where the switch K1 is closed and the switch K2 is opened;
fig. 4 is a structural diagram of an equivalent circuit of a low-cost insulation detection circuit in a state where a switch K1 is closed and a switch K2 is opened according to a second embodiment of the present invention;
fig. 5 is a circuit configuration diagram of the low-cost insulation detection circuit according to the second embodiment of the present invention in a state where the switch K1 is opened and the switch K2 is closed;
fig. 6 is a structural diagram of an equivalent circuit of a low-cost insulation detection circuit in a state where a switch K1 is opened and a switch K2 is closed according to a second embodiment of the present invention;
fig. 7 is a flowchart of a low-cost insulation detection method according to a third embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.
In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, "and/or" in the whole text includes three schemes, taking a and/or B as an example, including a technical scheme, and a technical scheme that a and B meet simultaneously; in addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
Fig. 1 is a schematic circuit diagram of a low-cost insulation detection circuit according to an embodiment of the present invention.
As shown in fig. 1, in the first embodiment, a low-cost insulation detection circuit is provided, which includes an insulation resistor RP, an insulation resistor RN, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a switch K1, a switch K2, and a battery management system; one end of the insulation resistor RP is connected to the positive electrode of an external battery pack and one end of the resistor R1, the other end of the insulation resistor RP is grounded, one end of the insulation resistor RN is connected to the negative electrode of the external battery pack and one end of the resistor R4, the other end of the insulation resistor RN is grounded, the other end of the resistor R1 is connected to one end of the resistor R2 and one end of the switch K1, the other end of the switch K1 is grounded, the other end of the resistor R2 is connected to one end of the resistor R3 and one end of the switch K2, the other end of the switch K2 is grounded, and the other end of the resistor R3 is connected to the other end of the resistor R4 and the battery management system; the insulation resistance RP is an insulation resistance of a positive electrode of an external battery pack to the ground, the insulation resistance RN is an insulation resistance of a negative electrode of the external battery pack to the ground, and the battery management system detects insulation impedances of the insulation resistance RP and the insulation resistance RN by controlling on and off of the switch K1 and the switch K2.
The low-cost insulation detection circuit in the embodiment of the invention optimizes the traditional resistance voltage division measurement method, can detect the insulation resistance by only two control switches, has no attenuation in performance, has a simplified circuit structure and an ultralow cost advantage, can further effectively reduce the risk of electric shock of people during operation, and improves the operation safety.
In some embodiments, on the basis of the above embodiments, the battery pack is applied to a battery high-voltage system or an energy storage battery high-voltage system of an electric vehicle.
Specifically, the resistor R1, the resistor R2, the resistor R3, and the resistor R4 are all high-precision voltage-dividing resistors.
In some embodiments, on the basis of the above embodiments, when the battery pack is applied to an electric vehicle battery high-voltage system, the insulation resistance RP represents the insulation resistance of the battery pack positive bus high voltage to an electric vehicle chassis, and the insulation resistance RN represents the insulation resistance of the battery pack negative bus high voltage to an electric vehicle chassis;
when the battery pack is applied to an energy storage battery high-voltage system, the insulation resistance RP represents the insulation resistance of the high voltage of the positive bus of the battery pack to the ground of the energy storage system, and the insulation resistance RN represents the insulation resistance of the high voltage of the negative bus of the battery pack to the ground of the energy storage system.
In particular, the switch K1 and the switch K2 are both controllable switches.
The low-cost insulation detection circuit in the embodiment of the invention optimizes the traditional resistance voltage division measurement method, can detect insulation resistances RP and RN only by two controllable switches K1 and K2, has no attenuation in performance, is simplified in circuit structure and has the advantage of ultralow cost. The design is not only suitable for the battery system of the electric automobile, but also suitable for insulation detection of the energy storage battery system.
The following is an embodiment of a low-cost insulation detection method provided by the present invention. The embodiment of the low-cost insulation detection method belongs to the same concept as the embodiment of the low-cost insulation detection circuit, and details which are not described in detail in the embodiment of the low-cost insulation detection method can be referred to the embodiment of the low-cost insulation detection circuit.
Fig. 2 is a flow chart of a low-cost insulation detection method according to a second embodiment of the present invention.
As shown in fig. 2, in the second embodiment, a low-cost insulation detection method is provided, which is applied to the low-cost insulation detection circuit, and includes the following steps:
s1: the battery management system sends a command, disconnects the switch K1 and the switch K2, and collects voltage V0 through an analog-to-digital converter;
specifically, the total battery pressure Vbat is calculated through the voltage V0, and the calculation formula is specifically:
wherein R1, R2, R3 and R4 are resistances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively.
Specifically, as shown in fig. 1, BGND is the negative terminal of the battery pack, PGND is the chassis (vehicle ground) of the electric vehicle or the energy storage system ground, and the voltage of the point a to the BGND is V0.
S2: the battery management system sends a command, closes the switch K1, opens the switch K2 and collects voltage V1 through an analog-to-digital converter;
please refer to fig. 3, which is a circuit structure diagram of the low-cost insulation detection circuit according to the second embodiment of the present invention in a state of closing the switch K1 and opening the switch K2.
Please refer to fig. 4, which is a structural diagram of an equivalent circuit of a low-cost insulation detection circuit in a state of closing the switch K1 and opening the switch K2 according to a second embodiment of the present invention.
Specifically, as shown in fig. 3 and 4, the calculation formula of the voltage V1 is specifically as follows:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
Specifically, as shown in fig. 3 and 4, the voltage of the a point pair BGND is V1, and the voltage of the B point pair BGND is Vm 1. When the switch K1 is closed and the switch K2 is opened, the voltage to the ground at the switch K1 is Vm1, and the calculation formula is specifically as follows:
wherein, R2, R3 and R4 are impedances of the resistor R2, the resistor R3 and the resistor R4, I1 is a current flowing through a total resistance of the circuit loop, and Rn is an insulation impedance of the insulation resistor Rn.
S3: the battery management system sends a command, opens the switch K1 and closes the switch K2, and acquires a voltage V2 through an analog-to-digital converter;
please refer to fig. 5, which is a circuit diagram illustrating a low-cost insulation detection circuit in a state of opening the switch K1 and closing the switch K2 according to a second embodiment of the present invention.
Please refer to fig. 6, which is a structural diagram of an equivalent circuit of a low-cost insulation detection circuit in a state of opening a switch K1 and closing a switch K2 according to a second embodiment of the present invention.
Specifically, as shown in fig. 5 and 6, the calculation formula of the voltage V2 is specifically as follows:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
Specifically, as shown in fig. 5 and 6, the voltage of the a-point pair BGND is V2, and the voltage of the B-point pair BGND is Vm 2. When the switch K1 is opened and the switch K2 is closed, the voltage to the ground at the switch K2 is Vm2, and the calculation formula is specifically as follows:
wherein, R3 and R4 are the impedances of the resistor R3 and the resistor R4, respectively, I2 is the current flowing through the total resistance of the circuit loop, and Rn is the insulation impedance of the insulation resistor Rn.
S4: calculating the insulation resistance of the insulation resistance RP and the insulation resistance RN by combining the voltage V0, the voltage V1 and the voltage V2;
wherein the battery management system is connected with the other end of the resistor R4 through the analog-to-digital converter.
In summary, as shown in fig. 1-2, in the low-cost insulation detection method according to the embodiment of the present invention, by measuring the voltage V0 at point a, the BMS may calculate the total voltage Vbat of the battery pack;
as shown in fig. 3 and 4, a relation with V1 and Rp, Rn may be derived;
as shown in fig. 5 and 6, a relation with V2 and Rp, Rn may be derived;
finally, the actual values of Rp and Rn can be calculated through the two relations.
The low-cost insulation detection method in the embodiment of the invention provides a low-cost (only two control switches) insulation detection architecture of a battery system (the detection scheme in the current market needs three or more switches to control and cooperate to perform insulation detection). The design is suitable for the high-voltage system of the battery of the electric automobile and the high-voltage system of the energy storage battery, the insulation impedance of the anode/cathode of the battery system to the whole chassis (the whole automobile ground) or the ground of the energy storage system can be accurately detected, and the risk of electric shock of people during operation is further effectively reduced.
Fig. 7 is a flowchart of a low-cost insulation detection method according to a third embodiment of the present invention.
As shown in fig. 7, in the third embodiment, a low-cost insulation detection method is provided, which is applied to the low-cost insulation detection circuit, and includes the following steps:
s1: the battery management system sends a command, disconnects the switch K1 and the switch K2, and collects voltage V0 through an analog-to-digital converter;
s2: the battery management system sends a command, closes the switch K1, opens the switch K2 and collects voltage V1 through an analog-to-digital converter;
s3: the battery management system sends a command, opens the switch K1 and closes the switch K2, and acquires a voltage V2 through an analog-to-digital converter;
s4: calculating the insulation resistance of the insulation resistance RP and the insulation resistance RN by combining the voltage V0, the voltage V1 and the voltage V2;
s5: and when the insulation impedance of the insulation resistor RP meets a preset first alarm condition and/or the insulation impedance of the insulation resistor RN meets a preset second alarm condition, sending an alarm signal.
Wherein the battery management system is connected with the other end of the resistor R4 through the analog-to-digital converter.
Specifically, the preset first alarm condition corresponds to the insulation resistance of the insulation resistor RP when the insulation performance is reduced, and the preset second alarm condition corresponds to the insulation resistance of the insulation resistor RN when the insulation performance is reduced.
The low-cost insulation detection method in the embodiment of the invention is a low-cost and high-precision insulation detection scheme of a battery system, and the technical scheme adopted by the method is described in detail as follows:
first, total pressure (Vbat) measurement:
the BMS sends commands to open the switch K1 and the switch K2;
the BMS acquires the voltage of the point a (see fig. 1) through an ADC (Analog-to-digital converter) port as follows: v0
The BMS calculates the Vbat voltage by equation (1):
secondly, the BMS sends a command to close the switch K1 (fig. 3), the switch K2 remains open;
thirdly, the BMS acquires the voltage of the point a (as shown in fig. 3) through the ADC port as: v1
FIG. 4 is an equivalent circuit in this state;
the total resistance of the circuit loop at this time is:
the current flowing through the total resistance at this time is:
at this time, the voltage Vm1 of the point B to BGND is:
then theoretically the voltage at point a, V1, should be:
substituting the formulas (1-4) into the formula (5) to obtain the relation of V1 with respect to Rp and Rn as follows:
fourthly, the BMS sends a command to open the switch K1 (fig. 5), while closing the switch K2;
fifthly, the BMS acquires the voltage of the point a (as shown in fig. 5) through the ADC port as follows: v2
FIG. 6 shows an equivalent circuit in this state;
the total resistance of the circuit loop at this time is:
the current flowing through the total resistance at this time is:
at this time, the voltage Vm2 of the point B to BGND is:
then theoretically the voltage at point a, V2, should be:
substituting the formula (1) and the formulas (7-9) into the formula (10) to obtain the relation of V1 on Rp and Rn as follows:
and sixthly, calculating the insulation resistances Rn and Rp by combining the formula (6) and the formula (11).
Rp(R1,R2,R3,R4,V1,V2,V0)
Rn(R1,R2,R3,R4,V1,V2,V0)
All of the above relevant parameters are known values.
The low-cost insulation detection method in the embodiment of the invention can effectively reduce the cost of insulation resistance detection, improves the safety of using a high-voltage system, and has the advantages of wide application range and high user experience.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (10)
1. A low-cost insulation detection circuit is characterized by comprising an insulation resistor RP, an insulation resistor RN, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a switch K1, a switch K2 and a battery management system; one end of the insulation resistor RP is connected to the positive electrode of an external battery pack and one end of the resistor R1, the other end of the insulation resistor RP is grounded, one end of the insulation resistor RN is connected to the negative electrode of the external battery pack and one end of the resistor R4, the other end of the insulation resistor RN is grounded, the other end of the resistor R1 is connected to one end of the resistor R2 and one end of the switch K1, the other end of the switch K1 is grounded, the other end of the resistor R2 is connected to one end of the resistor R3 and one end of the switch K2, the other end of the switch K2 is grounded, and the other end of the resistor R3 is connected to the other end of the resistor R4 and the battery management system; the insulation resistance RP is an insulation resistance of a positive electrode of an external battery pack to the ground, the insulation resistance RN is an insulation resistance of a negative electrode of the external battery pack to the ground, and the battery management system detects insulation impedances of the insulation resistance RP and the insulation resistance RN by controlling on and off of the switch K1 and the switch K2.
2. The low-cost insulation detection circuit according to claim 1, wherein the battery pack is applied to a battery high-voltage system of an electric vehicle or a battery high-voltage system of an energy storage battery.
3. The low cost insulation detection circuit of claim 2, wherein:
when the battery pack is applied to a battery high-voltage system of an electric automobile, the insulation resistance RP represents the insulation resistance of the high voltage of the positive bus of the battery pack to a chassis of the electric automobile, and the insulation resistance RN represents the insulation resistance of the high voltage of the negative bus of the battery pack to the chassis of the electric automobile;
when the battery pack is applied to an energy storage battery high-voltage system, the insulation resistance RP represents the insulation resistance of the high voltage of the positive bus of the battery pack to the ground of the energy storage system, and the insulation resistance RN represents the insulation resistance of the high voltage of the negative bus of the battery pack to the ground of the energy storage system.
4. A low-cost insulation detection method applied to the low-cost insulation detection circuit according to any one of claims 1 to 3, comprising the steps of:
s1: the battery management system sends a command, disconnects the switch K1 and the switch K2, and collects voltage V0 through an analog-to-digital converter;
s2: the battery management system sends a command, closes the switch K1, opens the switch K2 and collects voltage V1 through an analog-to-digital converter;
s3: the battery management system sends a command, opens the switch K1 and closes the switch K2, and acquires a voltage V2 through an analog-to-digital converter;
s4: calculating the insulation resistance of the insulation resistance RP and the insulation resistance RN by combining the voltage V0, the voltage V1 and the voltage V2;
wherein the battery management system is connected with the other end of the resistor R4 through the analog-to-digital converter.
5. The low-cost insulation detection method according to claim 4, wherein the total battery voltage Vbat is calculated through the voltage V0, and the calculation formula is specifically as follows:
wherein R1, R2, R3 and R4 are resistances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively.
6. The low-cost insulation detection method according to claim 5, wherein the calculation formula of the voltage V1 is specifically as follows:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
7. The low-cost insulation detection method according to claim 5, wherein the calculation formula of the voltage V2 is specifically as follows:
wherein R1, R2, R3 and R4 are impedances of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, respectively, Vbat is a total battery voltage, Rp is an insulation impedance of the insulation resistor Rp, and Rn is an insulation impedance of the insulation resistor Rn.
8. The low-cost insulation detection method according to claim 4, further comprising, after the step S4:
s5: and when the insulation impedance of the insulation resistor RP meets a preset first alarm condition and/or the insulation impedance of the insulation resistor RN meets a preset second alarm condition, sending an alarm signal.
9. The low-cost insulation detection method according to claim 4, wherein when the switch K1 is closed and the switch K2 is opened, the voltage to ground at the switch K1 is Vm1, and the calculation formula is as follows:
wherein, R2, R3 and R4 are impedances of the resistor R2, the resistor R3 and the resistor R4, I1 is a current flowing through a total resistance of the circuit loop, and Rn is an insulation impedance of the insulation resistor Rn.
10. The low-cost insulation detection method according to claim 4, wherein when the switch K1 is opened and the switch K2 is closed, the voltage to ground at the switch K2 is Vm2, and the calculation formula is as follows:
wherein, R3 and R4 are the impedances of the resistor R3 and the resistor R4, respectively, I2 is the current flowing through the total resistance of the circuit loop, and Rn is the insulation impedance of the insulation resistor Rn.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110240694.6A CN112858856B (en) | 2021-03-04 | 2021-03-04 | Low-cost insulation detection circuit and detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110240694.6A CN112858856B (en) | 2021-03-04 | 2021-03-04 | Low-cost insulation detection circuit and detection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112858856A true CN112858856A (en) | 2021-05-28 |
| CN112858856B CN112858856B (en) | 2023-10-03 |
Family
ID=75991624
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110240694.6A Active CN112858856B (en) | 2021-03-04 | 2021-03-04 | Low-cost insulation detection circuit and detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112858856B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113567743A (en) * | 2021-07-16 | 2021-10-29 | 东风汽车集团股份有限公司 | Detection system and method for electric vehicle power converter |
| WO2023223698A1 (en) * | 2022-05-20 | 2023-11-23 | パナソニックＩｐマネジメント株式会社 | Insulation resistance detection device and insulation resistance detection method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104049136A (en) * | 2013-03-11 | 2014-09-17 | 欣旺达电子股份有限公司 | High voltage cell set system isolation total voltage and insulation resistance detection circuit and detection method thereof |
| CN205176141U (en) * | 2015-11-07 | 2016-04-20 | 深圳市沃特玛电池有限公司 | Electric automobile battery insulation detecting system |
| CN108398645A (en) * | 2018-01-31 | 2018-08-14 | 山东魔方新能源科技有限公司 | A kind of electric automobile insulation impedance detection method |
| CN109100618A (en) * | 2017-06-20 | 2018-12-28 | 联合汽车电子有限公司 | High-tension battery Insulation Inspection System and method |
| CN109596888A (en) * | 2018-12-17 | 2019-04-09 | 深圳市超思维电子股份有限公司 | Insulation resistance detection method, detection circuit and the battery management system of automobile batteries |
| US20200072896A1 (en) * | 2018-08-31 | 2020-03-05 | Contemporary Amperex Technology Co., Limited | Insulation detection method |
| CN210155289U (en) * | 2019-06-19 | 2020-03-17 | 东软睿驰汽车技术（沈阳）有限公司 | Insulation detection circuit |
-
2021
- 2021-03-04 CN CN202110240694.6A patent/CN112858856B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104049136A (en) * | 2013-03-11 | 2014-09-17 | 欣旺达电子股份有限公司 | High voltage cell set system isolation total voltage and insulation resistance detection circuit and detection method thereof |
| CN205176141U (en) * | 2015-11-07 | 2016-04-20 | 深圳市沃特玛电池有限公司 | Electric automobile battery insulation detecting system |
| CN109100618A (en) * | 2017-06-20 | 2018-12-28 | 联合汽车电子有限公司 | High-tension battery Insulation Inspection System and method |
| CN108398645A (en) * | 2018-01-31 | 2018-08-14 | 山东魔方新能源科技有限公司 | A kind of electric automobile insulation impedance detection method |
| US20200072896A1 (en) * | 2018-08-31 | 2020-03-05 | Contemporary Amperex Technology Co., Limited | Insulation detection method |
| CN109596888A (en) * | 2018-12-17 | 2019-04-09 | 深圳市超思维电子股份有限公司 | Insulation resistance detection method, detection circuit and the battery management system of automobile batteries |
| CN210155289U (en) * | 2019-06-19 | 2020-03-17 | 东软睿驰汽车技术（沈阳）有限公司 | Insulation detection circuit |
Non-Patent Citations (1)
| Title |
|---|
| 苏肖: "电动汽车动力电池绝缘电阻检测方法研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113567743A (en) * | 2021-07-16 | 2021-10-29 | 东风汽车集团股份有限公司 | Detection system and method for electric vehicle power converter |
| WO2023223698A1 (en) * | 2022-05-20 | 2023-11-23 | パナソニックＩｐマネジメント株式会社 | Insulation resistance detection device and insulation resistance detection method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112858856B (en) | 2023-10-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108279373B (en) | Method and device for detecting charging switch of electric automobile | |
| CN109596888B (en) | Insulation resistance detection method and detection circuit of automobile battery and battery management system | |
| US20200064410A1 (en) | Insulation resistance detection circuit, detection method, and detection apparatus | |
| CN206038771U (en) | Electric automobile insulation resistance detection circuitry | |
| CN112858856A (en) | Low-cost insulation detection circuit and detection method | |
| CN111505532A (en) | Online detection method for early internal short circuit of series lithium battery pack based on SOC correlation coefficient | |
| CN106053947A (en) | Insulation resistance detection circuit and method of electric automobile power battery, and electric automobile | |
| CN101423032B (en) | Electric automobile super capacitance management system | |
| CN113655280B (en) | Insulation resistance value detection method during connection of power batteries of electric vehicles | |
| CN206074693U (en) | Insulating resistor detecting circuit | |
| CN110967557B (en) | Detection circuit and method | |
| CN209813744U (en) | Bidirectional charger and vehicle-to-vehicle charging system | |
| WO2024066550A1 (en) | Insulation test circuit and method for vehicle high-voltage line | |
| CN113655277A (en) | Insulation resistance value detection method during disconnection of power battery of electric automobile | |
| Liu et al. | Detection of ground insulation faults in ungrounded DC power supply systems by using a DC current injection method | |
| CN112285500A (en) | Insulation detection circuit and control method thereof | |
| CN113495202A (en) | Insulation detection circuit and method and electric automobile | |
| CN111123091A (en) | Electric vehicle relay adhesion detection circuit and adhesion detection method | |
| KR20210002971A (en) | Device for ground fault detection of electric car charger and method for the same | |
| CN114563732A (en) | Open-circuit fault diagnosis method for composite energy source power tube based on Longberger observer | |
| EP3958428B1 (en) | Control device, energy converting system, energy converting method, and storage medium | |
| CN111208350A (en) | Insulation detection circuit and energy storage charging equipment | |
| CN217521306U (en) | Insulation detection circuit for vehicle and electric vehicle | |
| US20160141863A1 (en) | Safety apparatus of fuel cell vehicle and method for controlling the safety apparatus | |
| CN216980831U (en) | Short-circuit protection control module of explosion-proof lithium battery system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |