CN110824374A - Low-cost high-voltage system total pressure detection circuit - Google Patents

Low-cost high-voltage system total pressure detection circuit Download PDF

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Publication number
CN110824374A
CN110824374A CN201911289692.5A CN201911289692A CN110824374A CN 110824374 A CN110824374 A CN 110824374A CN 201911289692 A CN201911289692 A CN 201911289692A CN 110824374 A CN110824374 A CN 110824374A
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China
Prior art keywords
resistor
branch
battery
relay
main
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Pending
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CN201911289692.5A
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Chinese (zh)
Inventor
张伟峰
程亚兵
汪园
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ZHEJIANG GAOTAI HAONENG TECHNOLORY CO Ltd
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ZHEJIANG GAOTAI HAONENG TECHNOLORY CO Ltd
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Priority to CN201911289692.5A priority Critical patent/CN110824374A/en
Publication of CN110824374A publication Critical patent/CN110824374A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/385Arrangements for measuring battery or accumulator variables
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/0084Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring voltage only
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/327Testing of circuit interrupters, switches or circuit-breakers
    • G01R31/3277Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
    • G01R31/3278Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Secondary Cells (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

The patent discloses a low-cost high-voltage system presses detection circuitry altogether aims at solving among the prior art high-voltage system and presses detection circuitry structure complicated problem that the cost is higher altogether. Electric automobile presses detection circuitry entirely, includes battery, main negative relay, branch road, No. two branch roads and No. three branch roads. The main negative relay is connected with the negative electrode of the battery; the first branch, the second branch and the third branch are connected in parallel and arranged between the main negative relay and the positive pole of the battery. The positive pole of battery is equipped with the test point, and the negative pole of battery is equipped with the test point, and the positive pole of main negative relay is equipped with the test point. The other type of total pressure detection circuit for the electric automobile comprises a battery, a first branch, a second branch, a third branch and a fourth branch. The first branch, the second branch and the third branch are connected in parallel and arranged between the main negative relay and the positive pole of the battery. The positive pole of battery is equipped with the test point, and the negative pole of battery is equipped with the test point, and the positive pole of main negative relay is equipped with the test point. The design of a resistance voltage division circuit is adopted, so that the cost is lower.

Description

Low-cost high-voltage system total pressure detection circuit
Technical Field
The utility model belongs to the electric automobile field, concretely relates to low-cost high-voltage system presses detection circuitry altogether.
Background
In response to the national 2025 program, the new energy automobile industry is rapidly developing, and the usage amount of batteries is increasing in the whole industry, and the demand amount of the BMS battery management system is also increasing.
In order to ensure the smooth operation of the battery, the indexes such as the adhesion state of the positive and negative relays, the total pressure of the battery and the like need to be detected; however, the existing electric vehicle total pressure detection circuit is complex in structure and high in cost, so that a low-cost electric vehicle total pressure detection circuit scheme can be provided, and the significance is remarkable for a battery management system.
Disclosure of Invention
The utility model provides a low-cost high-voltage system presses detection circuitry altogether, aims at solving among the prior art problem that the total pressure detection circuitry structure of electric automobile is complicated with higher costs.
In order to solve the technical problem, the technical scheme adopted by the disclosure is as follows:
in one aspect, the present disclosure provides a low-cost high-voltage system total pressure detection circuit, including battery, main negative relay S1, branch road one number, No. two branch roads and No. three branch roads. The main negative relay S1 is connected with the negative pole of the battery; the first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel. The first branch comprises a resistor R4 and a resistor R5 which are connected together in series; the resistor R4 is connected with the positive pole of the battery, and the resistor R5 is connected with the main negative relay S1; a test point V _ GPV is arranged between the resistor R4 and the resistor R5. The second branch comprises a resistor R1, a relay S2 and a resistor R2 which are sequentially connected in series; the resistor R1 is connected with the positive pole of the battery, and the resistor R2 is connected with the main negative relay S1; a test point V _ RTN1 is arranged between the relay S2 and the resistor R5. The third branch comprises a main positive relay, a resistor R6 and a resistor R7 which are sequentially connected in series; the main positive relay is connected with the positive electrode of the battery, and a series branch of a resistor R6 and a resistor R7 is connected between the main positive relay and a main negative relay S1 after being connected with the whole vehicle in parallel; a test point RTPn is arranged between the resistor R6 and the resistor R7. The main and negative relays S1 are connected in parallel with a resistor R3.
The further improved scheme is as follows: the low-cost electric automobile total pressure detection circuit further comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, and the main negative pre-charging branch circuit comprises a relay S3 and a resistor R8 which are sequentially connected in series. Whether the pre-charging is finished or not can be detected by using the main negative pre-charging branch circuit.
The further improved scheme is as follows: and a shunt is arranged between the main negative relay S1 and the whole vehicle. The current between the main negative relay S1 and the whole vehicle is detected.
On the other hand, this disclosure still provides a low-cost high-voltage system total pressure detection circuitry, including battery, branch road, No. two branch roads, No. three branch roads and No. four branch roads. The first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel. The first branch comprises a resistor R6 and a resistor R5 which are connected together in series; the resistor R6 is connected with the positive electrode of the battery, and the resistor R5 is connected with the negative electrode of the battery; a test point V _ GPV is arranged between the resistor R6 and the resistor R5. The second branch comprises a resistor R1, a resistor R2 and a resistor R3 which are sequentially connected in series; the resistor R1 is connected with the positive electrode of the battery, and the resistor R3 is connected with the negative electrode of the battery; a test point V _ RTN1 is arranged between the resistor R2 and the resistor R3. The third branch comprises a main positive relay RTP and two branches, and the two branches are connected in parallel and connected between the main positive relay RTP and the battery cathode; one branch circuit comprises a main negative relay S1 and a capacitor, the capacitor is connected between a main positive relay RTP and a main negative relay S1 after being connected with the whole vehicle in parallel, and the main negative relay S1 is connected with the negative electrode of the battery; the other branch comprises a resistor R7 and a resistor R8 which are connected in series, the resistor R7 is connected with the cathode of the battery, the resistor R8 is connected with a main positive relay RTP, and a test point V _ RTPn is arranged between the resistor R7 and the resistor R8. The fourth branch comprises a resistor R4, one end of a resistor R4 is connected between the resistor R1 and the resistor R2, and the other end of the resistor R4 is connected with the positive pole of the main negative relay S1.
The further improved scheme is as follows: the low-cost electric automobile total pressure detection circuit further comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, and the main negative pre-charging branch circuit comprises a relay S3 and a resistor R9 which are sequentially connected in series. Whether the pre-charging is finished or not can be detected by using the main negative pre-charging branch circuit.
The further improved scheme is as follows: a shunt is arranged between the main negative relay S1 and the negative pole of the battery. The current between the main negative relay S1 and the whole vehicle is detected.
The beneficial effect of this disclosure does:
this openly is equipped with a plurality of branches and test point, and when the relay state changed, through the detection of test point and simple resistance partial pressure calculation, the total pressure of detection battery that can be accurate to judge the adhesion condition of each relay.
The design of the resistance voltage-dividing circuit has the advantages that the cost is low, and meanwhile, the voltage of each position can be accurately calculated through resistance voltage division and kirchhoff law, so that accurate judgment can be made.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present disclosure and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings may be obtained from the drawings without inventive effort.
Fig. 1 is a schematic structural diagram of an electric vehicle total pressure detection circuit in a first embodiment of the disclosure.
Fig. 2 is a schematic structural diagram of an electric vehicle total pressure detection circuit in a second embodiment of the disclosure.
Detailed Description
The technical solution in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure. It should be understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to limit the disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the disclosure without inventive step, are within the scope of the disclosure.
The first embodiment is as follows:
as shown in fig. 1, the low-cost total pressure detection circuit for the electric vehicle of the embodiment includes a battery, a main negative relay S1, a first branch, a second branch, and a third branch. The main negative relay S1 is connected with the negative pole of the battery; the first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel.
The first branch comprises a resistor R4 and a resistor R5 which are connected together in series; the resistor R4 is connected with the positive pole of the battery, and the resistor R5 is connected with the main negative relay S1; a test point V _ GPV is arranged between the resistor R4 and the resistor R5.
The second branch comprises a resistor R1, a relay S2 and a resistor R2 which are sequentially connected in series; the resistor R1 is connected with the positive pole of the battery, and the resistor R2 is connected with the main negative relay S1; a test point V _ RTN1 is arranged between the relay S2 and the resistor R5.
The third branch comprises a main positive relay, a resistor R6 and a resistor R7 which are sequentially connected in series; the main positive relay is connected with the positive electrode of the battery, and a series branch of a resistor R6 and a resistor R7 is connected between the main positive relay and a main negative relay S1 after being connected with the whole vehicle in parallel; a test point RTPn is arranged between the resistor R6 and the resistor R7.
The main and negative relays S1 are connected in parallel with a resistor R3.
On the basis of the scheme, the low-cost electric vehicle total pressure detection circuit further comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, and the main negative pre-charging branch circuit comprises a relay S3 and a resistor R8 which are sequentially connected in series.
On the basis of any scheme, a shunt is arranged between the main negative relay S1 and the whole vehicle.
The total battery pressure and the adhesion state of each relay are detected as follows:
and (3) detecting the total pressure of the battery:
when S1 is in the closed state: and voltage values at two ends of the R5 are measured through the test point V _ GPV, and the total voltage value of the battery can be calculated through resistance voltage division.
When S1 is in the off state: disconnecting the S2, and forming a loop by the R4, the R5, the R3 and the battery to obtain an equation (the equation can be obtained by a person skilled in the art according to the resistance voltage division, and is not described herein, and the following equations are also not listed); s2 is closed, R4 and R5 are connected in series to form a branch, R1 and R2 are connected in series to form a branch, and the two branches are connected in parallel and then connected in series with R3 and a battery, so that another equation can be obtained; in the above equation, only V1 (the voltage value at the lower end of R5 in fig. 1) and the total cell pressure are unknown, so that the total cell pressure can be calculated.
Detecting the adhesion state of the main positive relay: if the voltage of the test point RTPn is 0, the main positive relay is in a disconnected state; otherwise, the main positive relay is in a closed state.
Detecting the adhesion state of the main and negative relays: the voltage difference between the positive electrodes of the batteries GPV and V1 changes, so that the sticking condition of the main negative relay S1 is judged.
Main negative pre-charge state diagnostic (precondition: main positive and negative relays S1 have been judged to be in the open state): since the resistor R8 is much smaller than the resistor R3, when the relay S3 is closed, no current can be seen at R3; the voltage difference A between the positive electrodes GPV and V1 of the battery is calculated through R1, R2 and R3 resistance voltage division. And comparing the differential pressure A with the total battery pressure to judge whether the pre-charging is finished.
Example two:
referring to fig. 2, a low-cost total pressure detection circuit for a high-voltage system includes a battery, a first branch, a second branch, a third branch, and a fourth branch. The first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel.
The first branch comprises a resistor R6 and a resistor R5 which are connected together in series; the resistor R6 is connected with the positive electrode of the battery, and the resistor R5 is connected with the negative electrode of the battery; a test point V _ GPV is arranged between the resistor R6 and the resistor R5.
The second branch comprises a resistor R1, a resistor R2 and a resistor R3 which are sequentially connected in series; the resistor R1 is connected with the positive electrode of the battery, and the resistor R3 is connected with the negative electrode of the battery; a test point V _ RTN1 is arranged between the resistor R2 and the resistor R3.
The third branch comprises a main positive relay RTP and two branches, and the two branches are connected in parallel and connected between the main positive relay RTP and the battery cathode; one branch circuit comprises a main negative relay S1 and a capacitor, the capacitor is connected between a main positive relay RTP and a main negative relay S1 after being connected with the whole vehicle in parallel, and the main negative relay S1 is connected with the negative electrode of the battery; the other branch comprises a resistor R7 and a resistor R8 which are connected in series, the resistor R7 is connected with the cathode of the battery, the resistor R8 is connected with a main positive relay RTP, and a test point V _ RTPn is arranged between the resistor R7 and the resistor R8.
The fourth branch comprises a resistor R4, one end of a resistor R4 is connected between the resistor R1 and the resistor R2, and the other end of the resistor R4 is connected with the positive pole of the main negative relay S1.
On the basis of the scheme, the low-cost electric vehicle total pressure detection circuit further comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, and the main negative pre-charging branch circuit comprises a relay S3 and a resistor R9 which are sequentially connected in series.
On the basis of the scheme, a shunt is arranged between the main negative relay S1 and the negative pole of the battery.
The total battery pressure and the adhesion state of each relay are detected as follows:
and (3) detecting the total pressure of the battery: and voltage at two ends of the R5 is measured through the test point V _ GPV, and the total battery voltage can be obtained through resistance voltage division calculation.
Detecting the adhesion state of the main positive relay: and when the voltage of the passing test point RTPn is 0, the main positive relay is in an open state, otherwise, the main positive relay is in a closed state.
Detecting the adhesion state of the main and negative relays: if the main negative relay S1 is in a closed state, three resistors R1, R2 and R3 are connected in series between the battery anode GPV and the battery cathode GNV, so that V _ RTN1 can be sampled through resistor voltage division, and then V1 (voltage value at the lower end of R1) voltage can be calculated; if the main negative relay S1 is in an open state, R2+ R3 and R4 are connected in parallel and then connected in series with R1, so that V _ RTN1 can be sampled through resistance voltage division, and then V1 voltage can be calculated. By comparing the voltage of V1 twice, whether the main and negative relays are adhered or not is judged.
Main negative pre-charge state diagnostic: calculating the voltage Vrtn between the GPV and the RTN1 through resistance voltage division of R1, R2, R3 and R4; by comparing the voltage Vrtn with the total battery voltage, it can be determined whether or not the precharge is completed.
In the above scheme, the calculation process of the resistance voltage division can be directly calculated by a person skilled in the art according to the scheme of the present application, and details are not described here.
The present disclosure is not limited to the above alternative embodiments, and any other various forms of products may be obtained by anyone in the light of the present disclosure, but any changes in shape or structure thereof fall within the scope of the present disclosure, which is defined by the claims of the present disclosure.

Claims (6)

1. A low-cost high-voltage system total pressure detection circuit which characterized in that: the device comprises a battery, a main negative relay S1, a first branch, a second branch and a third branch;
the main negative relay S1 is connected with the negative pole of the battery; the first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel;
the first branch comprises a resistor R4 and a resistor R5 which are connected together in series; the resistor R4 is connected with the positive pole of the battery, and the resistor R5 is connected with the main negative relay S1; a test point V _ GPV is arranged between the resistor R4 and the resistor R5;
the second branch comprises a resistor R1, a relay S2 and a resistor R2 which are sequentially connected in series; the resistor R1 is connected with the positive pole of the battery, and the resistor R2 is connected with the main negative relay S1; a test point V _ RTN1 is arranged between the relay S2 and the resistor R2;
the third branch comprises a main positive relay, a resistor R6 and a resistor R7 which are sequentially connected in series; the main positive relay is connected with the positive electrode of the battery, and a series branch of a resistor R6 and a resistor R7 is connected between the main positive relay and a main negative relay S1 after being connected with the whole vehicle in parallel; a test point RTPn is arranged between the resistor R6 and the resistor R7;
the main and negative relays S1 are connected in parallel with a resistor R3.
2. A low-cost total pressure detection circuit for a high-voltage system according to claim 1, wherein: the device also comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, wherein the main negative pre-charging branch circuit comprises a relay S3 and a resistor R8 which are sequentially connected together in series.
3. A low-cost total pressure detection circuit for a high-voltage system according to claim 1, wherein: and a shunt is arranged between the main negative relay S1 and the whole vehicle.
4. A low-cost high-voltage system total pressure detection circuit which characterized in that: the device comprises a battery, a first branch, a second branch, a third branch and a fourth branch;
the first branch, the second branch and the third branch are arranged between the main negative relay S1 and the positive pole of the battery in parallel;
the first branch comprises a resistor R6 and a resistor R5 which are connected together in series; the resistor R6 is connected with the positive electrode of the battery, and the resistor R5 is connected with the negative electrode of the battery; a test point V _ GPV is arranged between the resistor R6 and the resistor R5;
the second branch comprises a resistor R1, a resistor R2 and a resistor R3 which are sequentially connected in series; the resistor R1 is connected with the positive electrode of the battery, and the resistor R3 is connected with the negative electrode of the battery; a test point V _ RTN1 is arranged between the resistor R2 and the resistor R3;
the third branch comprises a main positive relay RTP and two branches, and the two branches are connected in parallel and connected between the main positive relay RTP and the battery cathode; one branch circuit comprises a main negative relay S1 and a capacitor, the capacitor is connected between a main positive relay RTP and a main negative relay S1 after being connected with the whole vehicle in parallel, and the main negative relay S1 is connected with the negative electrode of the battery; the other branch comprises a resistor R7 and a resistor R8 which are connected in series, the resistor R7 is connected with the cathode of the battery, the resistor R8 is connected with a main positive relay RTP, and a test point V _ RTPn is arranged between the resistor R7 and the resistor R8;
the fourth branch comprises a resistor R4, one end of a resistor R4 is connected between the resistor R1 and the resistor R2, and the other end of the resistor R4 is connected with the positive pole of the main negative relay S1.
5. The low-cost total pressure detection circuit of the high-voltage system according to claim 4, wherein: the device also comprises a main negative pre-charging branch circuit connected with the main negative relay S1 in parallel, wherein the main negative pre-charging branch circuit comprises a relay S3 and a resistor R9 which are sequentially connected together in series.
6. The low-cost total pressure detection circuit of the high-voltage system according to claim 4, wherein: a shunt is arranged between the main negative relay S1 and the negative pole of the battery.
CN201911289692.5A 2019-12-13 2019-12-13 Low-cost high-voltage system total pressure detection circuit Pending CN110824374A (en)

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Application Number Priority Date Filing Date Title
CN201911289692.5A CN110824374A (en) 2019-12-13 2019-12-13 Low-cost high-voltage system total pressure detection circuit

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113109703A (en) * 2021-04-07 2021-07-13 江苏开沃汽车有限公司 Circuit for monitoring adhesion of high-voltage relay and working method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113109703A (en) * 2021-04-07 2021-07-13 江苏开沃汽车有限公司 Circuit for monitoring adhesion of high-voltage relay and working method thereof

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