CN109347064B - Three-phase current sampling and overcurrent protection circuit - Google Patents
Three-phase current sampling and overcurrent protection circuit Download PDFInfo
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- CN109347064B CN109347064B CN201811157098.6A CN201811157098A CN109347064B CN 109347064 B CN109347064 B CN 109347064B CN 201811157098 A CN201811157098 A CN 201811157098A CN 109347064 B CN109347064 B CN 109347064B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
- H02H7/0833—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors for electric motors with control arrangements
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/083—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current for three-phase systems
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Abstract
The invention discloses a three-phase current sampling and overcurrent protection circuit, which comprises two current sensors, a current sampling input circuit, a third-phase current calculation circuit and an overcurrent comparison circuit, wherein the current sensors are connected with the current sampling input circuit; the two current sensors respectively sample two phases of the three phases of the motor controller, the current sampling input circuit is connected with the input end of the third phase current calculation circuit, the output end of the third phase current calculation circuit is connected with the input end of the overcurrent comparison circuit, and the output end of the overcurrent comparison circuit judges whether the third phase of the motor is in overcurrent or not. The circuit can reduce the use of one Hall current sensor, only needs one integrated operational amplifier chip, and calculates the third phase current value according to the current sampling values of two phases of the motor, so the circuit is simple and saves the cost. According to the protection method, a hardware circuit is used for building the overcurrent protection function of the motor controller, the response speed is higher than that of a software calculation control method during overcurrent, and the IGBT module can be protected better.
Description
Technical Field
The invention relates to a new energy automobile motor, in particular to a three-phase current sampling and overcurrent protection circuit.
Background
The motor of the new energy automobile adopts a torque control strategy, controller hardware is required to sample a three-phase current value to form control closed-loop feedback, and meanwhile, in order to prevent an abrupt overcurrent situation, overcurrent protection is set for the hardware, so that an IGBT driving module is protected instantly; at the present stage, a more mature scheme is applied: three Hall current sensors are used for sampling three-phase current values respectively, a three-phase current processing circuit is arranged, and the current sampling and overcurrent protection functions are achieved, as shown in the attached figure 1.
Patent document 1 (publication No. CN 204012661U) discloses a motor drive protection circuit, which controls the driving condition of a motor by the output of a hardware fault output terminal of a hardware self-checking function inside an IPM drive module itself and the output current of the IPM drive module, and when the IPM drive module recognizes that a fault occurs or the output current is abnormal, directly controls a level conversion module to stop working, so that the IPM drive module does not work, and further, the motor is cut off, thereby playing a role in motor drive protection.
The prior technical scheme has the following defects: 1. the motor controller needs to sample current of three-phase output, usually needs to use three current sensors, and the current of each phase needs to be sampled, so that the cost is high, and the installation is complicated. 2. The current value of the third phase is calculated using a software method, and it is determined whether an overcurrent is present. However, the software calculation mode has long time delay, and the IGBT module is easily damaged when an overcurrent condition occurs.
Disclosure of Invention
The invention aims to: the three-phase current sampling and overcurrent protection circuit only needs to use two current sensors, calculates the magnitude of the third phase current according to kirchhoff current law, is connected to an overcurrent comparison circuit to realize the overcurrent protection function, reduces the overall hardware cost, and is quicker in response time.
The technical scheme of the invention is as follows:
a three-phase current sampling and overcurrent protection circuit comprises two current sensors, a current sampling input circuit, a third-phase current calculation circuit and an overcurrent comparison circuit; the two current sensors respectively sample two phases of the three phases of the motor controller, the current sampling input circuit is connected with the input end of the third phase current calculation circuit, the output end of the third phase current calculation circuit is connected with the input end of the overcurrent comparison circuit, and the output end of the overcurrent comparison circuit judges whether the third phase of the motor is in overcurrent or not.
Preferably, the current sampling circuit comprises two operational amplifiers U1A and U1C, and the voltage following and isolation functions are respectively realized on the sampling input signals of the two current sensors.
Preferably, the third phase current calculating circuit comprises two operational amplifiers U1D and U1B, wherein U1D forms a voltage follower circuit for providing a stable voltage to U1B, U1B forms a phase current calculating circuit, and two outputs of the current sampling circuit are respectively connected to the input terminals of the phase current calculating circuit, so as to calculate the magnitude of the current of the third phase motor and generate a constant voltage source.
Preferably, the overcurrent comparison circuit includes comparators U2A and U2B, and compares the output voltage of the third-phase current calculation circuit with the voltages of the two reference points, respectively, to implement the function of overcurrent comparison.
Preferably, the operational amplifiers U1A, U1C, U1D, U1B belong to one integrated operational amplifier U1; the comparators U2A and U2B belong to an integrated chip U2.
The invention has the advantages that:
1. the circuit of the invention can reduce the use of one Hall current sensor in the motor controller, and reduce the overall cost of the motor controller. The circuit only needs one integrated operational amplifier chip, 4 operational amplifiers are integrated in the chip, the third phase current value is calculated according to the current sampling values of the two phases of the motor, the circuit is simple, and the cost is saved.
2. This patent uses hardware circuit to build the protect function of machine controller overcurrent, and response speed is faster than software control's method during overcurrent, the protection IGBT module that can be better.
Drawings
The invention is further described with reference to the following figures and examples:
FIG. 1 is a functional block diagram of prior art current sampling and over-current protection;
FIG. 2 is a schematic block diagram of a three-phase current sampling and overcurrent protection circuit of the present invention;
FIG. 3 is a flow chart of the operation of the three-phase current sampling and overcurrent protection circuit of the present invention;
fig. 4 is a schematic diagram of an embodiment of a three-phase current sampling and overcurrent protection circuit according to the present invention.
Detailed Description
As shown in fig. 2, the present invention discloses a three-phase current sampling and overcurrent protection circuit. Only two current sensors are needed to be used in the motor controller to sample the current of two phases of the three phases of the motor controller, and then the current value of the third phase of the motor controller is calculated through a hardware circuit. The value is sent to an overcurrent comparison circuit, and an overcurrent protection function is realized in a hardware mode.
The current sampling and overcurrent protection circuit comprises: a current sampling input circuit, a third phase current calculation circuit and an overcurrent comparison circuit, as shown in fig. 3; the current sampling circuit comprises two operational amplifiers, is used for sampling and isolating the input signal and filtering the input signal; the third-phase current calculating circuit comprises two operational amplifiers and a resistance device and is used for calculating the current of the third-phase motor and generating a constant voltage source; the overcurrent determination circuit includes two comparators and a resistance-capacitance device, compares a current value of the third phase with an overcurrent point, and determines whether the third phase of the motor has an overcurrent.
Fig. 4 is a schematic diagram of an embodiment of a three-phase current sampling and overcurrent protection circuit according to the present invention.
The current sampling input circuit comprises operational amplifiers U1A, U1C. Wherein U1 is an integrated operational amplifier, and 4 operational amplifiers are integrated inside. Pin 4 of U1A is connected to the power supply VCC, pin 11 is connected to the first reference ground, pin 3 of U1A is connected to the output terminal of the U-phase current sensor, pin 1 of U1A is connected to one end of the R3 resistor and pin 2 of U1A. U1A reads the current sample value of U phase current sensor to realize voltage following and isolation function, guarantee that the processing of circuit poststage does not have the influence to the preceding stage.
The pin 10 of U1C is connected to the output end of the W-phase current sensor, and the pin 10 of U1C is connected to one end of the R5 resistor and the pin 9 of U1C. U1C reads the current sample value of W phase current sensor to realize voltage following and isolation function, guarantee that the processing of circuit poststage does not have the influence to the preceding stage.
The third-phase current calculating circuit comprises operational amplifiers U1B and U1D, resistors R1, R3, R5, R6, R7, R10, R12 and R14. Wherein one end of R10 is connected to one end of R12, the other end is connected to power VCC, the other end of R12 is connected to one end of R14, and the other end of R14 is connected to the first reference ground; r10, R12, R14 constitute a voltage dividing circuit, and a constant voltage is formed at the intersection of R10 and R12.
The 12 pin of U1D is connected to the intersection point of R10 and R12, the 14 pin of U1D is connected with the 13 pin of U1D, and U1D forms a voltage follower circuit, so that the voltage follower circuit realizes the voltage follower of the post stage to the front stage, and the post stage processing of the circuit is ensured to have no influence on the front stage.
R3 is connected to the 1 pin of U1A at one end and the 6 pin of U1B at the other end; r5 is connected to U1C at one end and U1B at the other end at the pin 8; one end of R6 is connected to the 14 pin of U1D, and the other end is connected to the 5 pin of U1B; one end of R1 is connected to the 6 feet of U1B, and the other end is connected to the 7 feet of U1B; the resistors R1, R3, R5, R6, R7, and U1B constitute a phase current calculation circuit, and a current of the third phase can be calculated by the circuit.
The overcurrent comparison circuit comprises comparators U2A and U2B, resistors R2, R8, R9, R13, R4 and R11, and capacitors C3 and C1. U2 is an integrated chip including two comparators inside. One end of R2 is connected to VCC, the other end is connected to one end of R8, the other end of R8 is connected to one end of resistor R9, the other end of R9 is connected to one end of R13, and the other end of R13 is connected to the first reference ground. The capacitor C2 is connected with the R2 in parallel, and the capacitor R3 is connected with the R13 in parallel. The resistors R2, R8, R9 and R13 and the capacitors C2 and C3 form a voltage reference circuit and form two voltage reference points.
The pin 1 of U2A is connected to the overcurrent judgment output point I _ OVER; the 2 pin of U2A is connected to the 5 pin of U2B, and the 2 pin of U2A is also connected to one end of R4 and one end of R11; the 3-pin of U2A is connected to the connection point of R2 and R8; the pin 8 of the U2A is connected to a power supply VCC, and also connected to one end of a capacitor C1, and the other end of the capacitor C1 is connected to a first reference ground.
The 5 feet of U2B are connected with the intersection point of R4 and R11; the 6-pin of U2B is connected to the intersection of R9 and R13; pin 7 of U2B is connected to an overcurrent determination output point I _ OVER. The other end of R11 is connected to the first reference ground, and the other end of R4 is connected to the 7-pin of U1B. The resistors R4 and R11, the capacitor C1 and the comparators U2A and U2B form a voltage comparison circuit, and the voltage output by the pin 7 of the U1B is compared with the voltages of two reference points, so that the function of overcurrent comparison is realized.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose of the embodiments is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All modifications made according to the spirit of the main technical scheme of the invention are covered in the protection scope of the invention.
Claims (1)
1. A three-phase current sampling and overcurrent protection circuit is characterized in that: the device comprises two current sensors, a current sampling circuit, a third phase current calculating circuit and an overcurrent comparing circuit; the two current sensors respectively sample two phases of the three phases of the motor controller, the two current sensors are connected with the input end of a third phase current calculating circuit through a current sampling circuit, the output end of the third phase current calculating circuit is connected with the input end of an overcurrent comparing circuit, and the output end of the overcurrent comparing circuit judges whether the third phase of the motor is in overcurrent or not;
the current sampling circuit comprises two operational amplifiers U1A and U1C, and the voltage following and isolating functions are respectively realized on sampling input signals of the two current sensors;
the third-phase current calculating circuit comprises two operational amplifiers U1D and U1B, wherein U1D forms a voltage following circuit and provides stable voltage for U1B, U1B forms a phase current calculating circuit, and two paths of outputs of the current sampling circuit are respectively connected with the input end of the phase current calculating circuit and are used for calculating the current of the third-phase motor and generating a constant voltage source;
the overcurrent comparison circuit comprises comparators U2A and U2B, and the output voltage of the third-phase current calculation circuit is compared with the voltages of two reference points respectively to realize the function of overcurrent comparison;
the operational amplifiers U1A, U1C, U1D and U1B belong to an integrated operational amplifier U1; the comparators U2A and U2B belong to an integrated chip U2, wherein: the power supply end of the U1A is connected to a power supply VCC, the ground end is connected to a first reference ground, the non-inverting input end of the U1A is connected to the output end of the U-phase current sensor, and the output end of the U1A is connected to one end of the R3 resistor and the inverting input end of the U1A; U1A reads the current sampling value of the U-phase current sensor, and realizes the voltage following and isolating functions, thus ensuring that the processing of the rear stage of the circuit has no influence on the front stage;
the non-inverting input end of the U1C is connected to the output end of the W-phase current sensor, and the output end of the U1C is connected to one end of the R5 resistor and the inverting input end of the U1C; U1C reads the current sampling value of the W-phase current sensor, and realizes the voltage following and isolating functions, thus ensuring that the processing of the rear stage of the circuit has no influence on the front stage; wherein one end of R10 is connected to one end of R12, the other end is connected to power VCC, the other end of R12 is connected to one end of R14, and the other end of R14 is connected to the first reference ground; r10, R12 and R14 form a voltage dividing circuit, and a constant voltage is formed at the intersection point of R10 and R12;
the positive phase input end of the U1D is connected to the intersection point of the R10 and the R12, the output end of the U1D is connected with the negative phase input end of the U1D, and the U1D forms a voltage follower circuit, so that the following stage voltage follows the preceding stage, and the processing of the following stage of the circuit is ensured to have no influence on the preceding stage;
one end of R3 is connected to the output end of U1A, and the other end is connected to the inverting input end of U1B; one end of R5 is connected to the output end of U1C, and the other end is connected to the inverting input end of U1B; one end of the R6 is connected to the output end of the U1D, and the other end of the R6 is connected to the positive input end of the U1B; one end of the R1 is connected to the inverting input end of the U1B, and the other end of the R1 is connected to the output end of the U1B; the resistors R1, R3, R5, R6, R7 and U1B form a phase current calculating circuit, and the current of the third phase can be calculated through the circuit;
the overcurrent comparison circuit comprises comparators U2A and U2B, resistors R2, R8, R9, R13, R4, R11, capacitors C3 and C1; one end of R2 is connected to power VCC, the other end is connected to one end of R8, the other end of R8 is connected to one end of resistor R9, the other end of R9 is connected to one end of R13, and the other end of R13 is connected to a first reference ground; the capacitor C2 is connected with the R2 in parallel, and the capacitor R3 is connected with the R13 in parallel; the resistors R2, R8, R9 and R13 and the capacitors C2 and C3 form a voltage reference circuit to form two voltage reference points;
the output end of the U2A is connected to an overcurrent judgment output point I _ OVER; the inverting input terminal of U2A is connected to the non-inverting input terminal of U2B, and the inverting input terminal of U2A is also connected to one terminal of R4 and one terminal of R11; the non-inverting input terminal of U2A is connected to the connection point of R2 and R8; the power supply end of the U2A is connected to a power supply VCC and also connected to one end of a capacitor C1, and the other end of the capacitor C1 is connected to a first reference ground;
the non-inverting input end of U2B is connected with the intersection of R4 and R11; the inverting input of U2B is connected to the intersection of R9 and R13; the output end of the U2B is connected to an overcurrent judgment output point I _ OVER; the other end of R11 is connected to the first reference ground, and the other end of R4 is connected to the output end of U1B; the resistors R4 and R11, the capacitor C1 and the comparators U2A and U2B form a voltage comparison circuit, and the voltage output by the output end of the U1B is compared with the voltages of two reference points, so that the function of overcurrent comparison is realized.
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| CN110031095B (en) * | 2019-04-29 | 2021-07-27 | 安徽安匠信息科技有限公司 | Reverse bias generation method for avalanche photodiode |
| CN110265973A (en) * | 2019-06-19 | 2019-09-20 | 贵州航天林泉电机有限公司苏州分公司 | Bilateral electric current hardware protection circuit device suitable for brushless direct current motor driver |
| CN111426868B (en) * | 2020-04-23 | 2022-03-29 | 合肥巨一动力系统有限公司 | Controller current sampling system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201490697U (en) * | 2009-05-11 | 2010-05-26 | 奇瑞汽车股份有限公司 | Three-phase current detection and protection circuit |
| CN205786809U (en) * | 2016-05-27 | 2016-12-07 | 浙江正泰电器股份有限公司 | The three-phase output current sampling circuit of converter |
| CN206193083U (en) * | 2016-11-02 | 2017-05-24 | 中车大连电力牵引研发中心有限公司 | Detection circuitry of three phase motor phase voltage |
| CN106911122A (en) * | 2017-02-28 | 2017-06-30 | 重庆长安汽车股份有限公司 | A kind of motor controller overcurrent protection device, electric machine controller and electric automobile |
| CN207366625U (en) * | 2017-09-15 | 2018-05-15 | 深圳市沃特玛电池有限公司 | A kind of current sampling circuit based on Hall |
-
2018
- 2018-09-30 CN CN201811157098.6A patent/CN109347064B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201490697U (en) * | 2009-05-11 | 2010-05-26 | 奇瑞汽车股份有限公司 | Three-phase current detection and protection circuit |
| CN205786809U (en) * | 2016-05-27 | 2016-12-07 | 浙江正泰电器股份有限公司 | The three-phase output current sampling circuit of converter |
| CN206193083U (en) * | 2016-11-02 | 2017-05-24 | 中车大连电力牵引研发中心有限公司 | Detection circuitry of three phase motor phase voltage |
| CN106911122A (en) * | 2017-02-28 | 2017-06-30 | 重庆长安汽车股份有限公司 | A kind of motor controller overcurrent protection device, electric machine controller and electric automobile |
| CN207366625U (en) * | 2017-09-15 | 2018-05-15 | 深圳市沃特玛电池有限公司 | A kind of current sampling circuit based on Hall |
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Effective date of registration: 20190605 Address after: 201807 600 Huiwang Road, Jiading District, Shanghai Applicant after: Shanghai Automotive Transmission Co., Ltd. Address before: 230051 Shanghai Road, Baohe Industrial Zone, Hefei, Anhui, East Dalian Road North Applicant before: HEFEI JUYI POWER SYSTEM CO., LTD. |
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