CN113765466B - Overvoltage protection circuit, overvoltage protection method and motor controller - Google Patents
Overvoltage protection circuit, overvoltage protection method and motor controller Download PDFInfo
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- CN113765466B CN113765466B CN202111096382.9A CN202111096382A CN113765466B CN 113765466 B CN113765466 B CN 113765466B CN 202111096382 A CN202111096382 A CN 202111096382A CN 113765466 B CN113765466 B CN 113765466B
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- 238000000034 method Methods 0.000 title claims abstract description 43
- 238000005070 sampling Methods 0.000 claims abstract description 135
- 238000002955 isolation Methods 0.000 claims description 27
- 239000003990 capacitor Substances 0.000 claims description 20
- 230000008569 process Effects 0.000 claims description 14
- 230000011664 signaling Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 7
- 238000010248 power generation Methods 0.000 description 6
- 230000001360 synchronised effect Effects 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
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- 230000008859 change Effects 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
- H02P29/02—Providing protection against overload without automatic interruption of supply
- H02P29/024—Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load
- H02P29/0241—Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load the fault being an overvoltage
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Abstract
The invention discloses an overvoltage protection circuit, an overvoltage protection method and a motor controller, and belongs to the technical field of high voltage. The overvoltage protection circuit comprises a voltage sampling circuit, an overvoltage comparison circuit, a signal processing circuit and a driving execution circuit which are sequentially connected, wherein the voltage sampling circuit samples the voltage of a direct current bus to generate a voltage sampling signal, the overvoltage comparison circuit compares the voltage sampling signal with a first reference voltage, when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage, an overvoltage signal is generated, the signal processing circuit performs signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal, and the driving execution circuit controls a motor controller to enter a safe state according to the enabling signal and the active short-circuit signal. According to the invention, the direct current bus is subjected to voltage sampling, and when the sampling voltage of a voltage sampling signal exceeds a first reference voltage, the driving motor control system is controlled to enter a safe state, so that the rapid hardware overvoltage protection is realized.
Description
Technical Field
The invention relates to the technical field of high voltage, in particular to an overvoltage protection circuit, an overvoltage protection method and a motor controller.
Background
When the vehicle is in a high-speed power generation running state and the battery main contactor is in an abnormal disconnection state, the voltage at two ends of the direct current bus capacitor connected with the driving motor controller can generate overvoltage phenomenon due to the impact of the counter potential of the permanent magnet synchronous motor, the overvoltage phenomenon can be aggravated along with the increase of the counter potential of the motor and the increase of the power generation power, and overvoltage protection is needed when the overvoltage phenomenon occurs, so that equipment damage or safety accidents are avoided.
At present, the driving motor controller is usually required to be switched from a normal operation mode to a safety mode within a period of tens of microseconds to hundreds of microseconds, and the action time of the existing hardware overvoltage protection scheme is tens of microseconds to hundreds of microseconds, but when the counter potential of the permanent magnet synchronous motor is far higher than the withstand voltage value of a high-voltage component in the driving motor control system or the power generated by a vehicle is larger, the driving motor controller is required to be switched from the normal operation mode to the safety mode within a shorter period of time.
The foregoing is provided merely for the purpose of facilitating understanding of the technical solutions of the present invention and is not intended to represent an admission that the foregoing is prior art.
Disclosure of Invention
The invention mainly aims to provide an overvoltage protection circuit, an overvoltage protection method and a motor controller, and aims to solve the technical problem that the high-voltage safety of high-voltage components in a driving motor controller cannot be effectively guaranteed in the prior art.
In order to achieve the above object, the present invention provides an overvoltage protection circuit, which includes a voltage sampling circuit, an overvoltage comparing circuit, a signal processing circuit and a driving executing circuit, which are sequentially connected;
The voltage sampling circuit is used for sampling the voltage of the direct current bus and generating a voltage sampling signal;
The overvoltage comparison circuit is used for comparing the voltage sampling signal with a first reference voltage, and generating an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage;
the signal processing circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal;
The driving execution circuit is used for controlling the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal;
The voltage sampling circuit is used for sampling the voltage of the direct current bus and generating a voltage sampling signal;
The overvoltage comparison circuit is used for comparing the voltage sampling signal with a first reference voltage, and generating an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage;
the signal processing circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal;
And the driving execution circuit is used for controlling the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal.
Optionally, the signal processing circuit comprises a digital isolation circuit and a logic inverting circuit which are connected in parallel;
the digital isolation circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal;
and the logic inverting circuit is used for performing signal processing according to the overvoltage signal to generate an active short-circuit signal.
Optionally, the logic inverting circuit comprises a switching tube;
The control end of the switching tube is connected with the overvoltage comparison circuit, the first end of the switching tube is connected with a power supply, and the second end of the switching tube is connected with a direct current bus.
Optionally, the logic inverting circuit further comprises a delay circuit.
Optionally, the delay circuit includes a first resistor and a first capacitor;
the first end of the first resistor is connected with the overvoltage comparison circuit, and the second end of the first resistor is connected with the control end of the switching tube; the first end of the second capacitor is connected with the second end of the first resistor, and the second end of the second capacitor is connected with the second end of the switch tube.
Optionally, the overvoltage signal input end of the digital isolation circuit and the overvoltage signal input end of the logic inverting circuit are respectively connected with the overvoltage signal output end of the overvoltage comparison circuit, the low-voltage side enabling signal output end of the digital isolation circuit is connected with the low-voltage side enabling signal input end of the driving execution circuit, and the high-voltage side enabling signal output end of the logic inverting circuit is respectively connected with the high-voltage side enabling signal input end of the driving execution circuit.
In addition, to achieve the above object, the present invention also provides an overvoltage protection method applied to the above overvoltage protection circuit, the overvoltage protection circuit including: the device comprises a voltage sampling circuit, an overvoltage comparison circuit, a signal processing circuit and a driving execution circuit;
the overvoltage protection method comprises the following steps:
The voltage sampling circuit performs voltage sampling on the direct current bus to generate a voltage sampling signal;
The overvoltage comparison circuit performs voltage comparison on the voltage sampling signal and a first reference voltage, and generates an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage;
The signal processing circuit performs signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal;
And the driving execution circuit controls the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal.
Optionally, the driving execution circuit controls the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal, including:
When the sampling voltage is larger than the first reference voltage, the driving execution circuit controls all bridge arms of the motor controller to be turned off according to the enabling signal, and controls the upper bridge arm or the lower bridge arm of the motor controller to be turned on according to the preset delay time of the active short circuit signal;
And in the process that the sampling voltage is reduced from the first reference voltage to the second reference voltage, the upper bridge arm or the lower bridge arm of the motor controller is kept to be conducted.
Optionally, after keeping the upper bridge arm or the lower bridge arm of the motor controller conductive during the process of the sampling voltage dropping from the first reference voltage to the second reference voltage, the method includes:
When the sampling voltage is smaller than the second reference voltage, controlling all bridge arms of the motor controller to be turned off according to the enabling signal, and controlling the upper bridge arm or the lower bridge arm of the motor controller to be turned off according to the preset delay time of the active short circuit signal;
and in the process that the sampling voltage is increased from the second reference voltage to the first reference voltage, keeping all bridge arms of the motor controller to be switched off.
In addition, to achieve the above object, the present invention also provides a motor controller including the overvoltage protection circuit as described above, or applied to the overvoltage protection method as described above.
The overvoltage protection circuit comprises a voltage sampling circuit, an overvoltage comparison circuit, a signal processing circuit and a driving execution circuit which are sequentially connected, wherein the voltage sampling circuit samples the voltage of a direct current bus to generate a voltage sampling signal, the overvoltage comparison circuit compares the voltage sampling signal with a first reference voltage, when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage, an overvoltage signal is generated, the signal processing circuit performs signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal, and the driving execution circuit controls a motor controller to enter a safe state according to the enabling signal and the active short-circuit signal. According to the invention, the direct current bus is subjected to voltage sampling, and when the sampling voltage of a voltage sampling signal exceeds a first reference voltage, the driving motor control system is controlled to enter a safe state, so that the rapid hardware overvoltage protection is realized only through hardware.
Drawings
FIG. 1 is a schematic diagram of a first embodiment of an overvoltage protection circuit according to the present invention;
FIG. 2 is a schematic diagram of a second embodiment of an overvoltage protection circuit according to the present invention;
FIG. 3 is a schematic diagram of an embodiment of an overvoltage protection circuit according to the present invention;
FIG. 4 is a schematic flow chart of an embodiment of the overvoltage protection circuit of the present invention;
Fig. 5 is a logic diagram of a switching mode of a safety state according to an embodiment of the overvoltage protection method of the present invention.
Reference numerals illustrate:
| Reference numerals | Name of the name | Reference numerals | Name of the name |
| 100 | Voltage sampling circuit | 300 | Signal processing circuit |
| 200 | Overvoltage comparison circuit | 400 | Drive execution circuit |
| R1～R6 | First to sixth resistors | 101 | A first voltage dividing unit |
| C1～C2 | First to second capacitors | 102 | Second voltage division unit |
| HVDC_P | High-voltage positive electrode terminal of direct current bus | 301 | Digital isolation circuit |
| HVDC_N | High-voltage negative electrode terminal of direct current bus | 302 | Logic inverting circuit |
| Vref | Reference voltage | CP1 | Digital isolation chip |
| Safe state | Safety state | CP2 | Driving chip |
| ASC | Active short circuit | T1 | Triode transistor |
| Freewheeling | Freewheel state | A1 | Comparator with a comparator circuit |
| U1 | First reference voltage | VDD | Power supply |
| U2 | Second reference voltage | Udc | DC bus voltage |
The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
An embodiment of the present invention provides an overvoltage protection circuit, referring to fig. 1, fig. 1 is a schematic structural diagram of a first embodiment of the overvoltage protection circuit of the present invention.
The overvoltage protection circuit comprises a voltage sampling circuit 100, an overvoltage comparison circuit 200, a signal processing circuit 300 and a driving execution circuit 400 which are sequentially connected.
It should be noted that, the voltage sampling end of the voltage sampling circuit 100 is connected to the high voltage end of the dc bus, the voltage sampling signal output end of the voltage sampling circuit 100 is connected to the voltage sampling signal input end of the overvoltage comparing circuit 200, the overvoltage signal output end of the overvoltage comparing circuit 200 is connected to the overvoltage signal input end of the signal processing circuit 300, the enable signal output end of the signal processing circuit 300 is connected to the enable signal input end of the driving executing circuit 400, and the control end of the driving executing circuit 400 is connected to the control end of the driving motor control system.
It is easy to understand that when high-speed power generation occurs and the main battery contactor is abnormally disconnected, the overvoltage protection circuit controls the driving motor control system, and the driving motor control system can be switched from a normal operation mode to a safe state (active short-circuit state) within ten microseconds, so that an energy transmission loop between the permanent magnet synchronous motor and the high-voltage direct current bus is rapidly cut off, and the voltages on two sides of the high-voltage direct current bus are controlled within a high-voltage component withstand voltage range, so that a high-voltage safety target of the whole vehicle is met.
The voltage sampling circuit 100 is configured to sample a voltage of a dc bus and generate a voltage sampling signal.
It should be understood that the voltage sampling circuit 100 may sample the voltage of the dc bus by adopting a resistor voltage division manner, the voltage sampling signal may include the sampled voltage of the dc bus, that is, a voltage sampling result, and the voltage division resistance value may be determined according to the voltage class of the dc bus, so as to ensure the safe use of the overvoltage protection circuit while realizing accurate voltage sampling.
The overvoltage comparing circuit 200 is configured to compare the voltage sampling signal with a first reference voltage, and generate an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage.
It will be appreciated that the overvoltage comparing circuit 200 may first filter the voltage sampling signal to remove redundant clutter in the sampling process, and then compare the sampling voltage in the filtered voltage sampling signal with a first provided reference voltage, where the first reference voltage may be a minimum value in a voltage withstanding range of a high voltage component inside the driving motor controller.
It is easy to understand that, by voltage comparison, when the sampled voltage of the dc bus is greater than or equal to the first reference voltage, the overvoltage comparing circuit 200 generates an overvoltage signal that may be a low level signal, and when the signal is a low level, an overvoltage fault occurs, and correspondingly, when the sampled voltage does not exceed the first reference voltage, the overvoltage comparing circuit 200 generates an overvoltage signal that may be a high level signal, and when the signal is a high level, an overvoltage fault does not occur or the overvoltage fault has disappeared.
The signal processing circuit 300 is configured to perform signal processing according to the overvoltage signal, and generate an enable signal and an active short-circuit signal.
It is understood that the signal processing circuit 300 may signal isolate or logically invert the overvoltage signal. When the generated enable signal is applied to the low voltage side of the driving execution circuit 400, the driving execution circuit 400 may be enabled to cause the driving execution circuit 400 to execute the pulse width modulation transmission, if the enable signal is a high level signal, and the driving execution circuit 400 may be turned off to prohibit the driving execution circuit 400 from executing the pulse width modulation transmission, if the enable signal is a low level signal.
It should be appreciated that by logically inverting the over-voltage signal, the driver execution circuit 400 may be caused to output a high level when the generated active short circuit signal acts on the high side of the driver execution circuit 400. The priority of the high side active short signal (high side enable signal) is higher than the priority of the low side enable signal.
The driving execution circuit 400 is configured to control the motor controller to enter a safe state according to the enable signal and the active short-circuit signal.
It is easy to understand that the driving execution circuit 400 may first make its own enable pin in a low level invalid state according to the low voltage side enable signal, and then control the driving motor control system to enter a safe state according to the high voltage side active short circuit signal, and enter the safe state within ten microseconds before the dc bus voltage exceeds the maximum value in the withstand voltage range of the high voltage component inside the driving motor controller, so as to implement fast hardware overvoltage protection.
The overvoltage protection circuit of this embodiment includes a voltage sampling circuit 100, an overvoltage comparing circuit 200, a signal processing circuit 300 and a driving executing circuit 400 which are sequentially connected, the voltage sampling circuit 100 performs voltage sampling on a dc bus to generate a voltage sampling signal, the overvoltage comparing circuit 200 performs voltage comparison on the voltage sampling signal and a first reference voltage, when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage, an overvoltage signal is generated, the signal processing circuit 300 performs signal processing according to the overvoltage signal to generate an enable signal and an active short-circuit signal, and the driving executing circuit 400 controls a motor controller to enter a safe state according to the enable signal and the active short-circuit signal. According to the invention, the direct current bus is subjected to voltage sampling, and when the sampling voltage of a voltage sampling signal exceeds a first reference voltage, the driving motor control system is controlled to enter a safe state, so that the rapid overvoltage protection is realized only through hardware.
Based on the first embodiment of the present invention, a second embodiment of the overvoltage protection circuit of the present invention is proposed, and referring to fig. 2 and 3, fig. 2 is a schematic structural diagram of the second embodiment of the overvoltage protection circuit of the present invention, and fig. 3 is a circuit schematic of an embodiment of the overvoltage protection circuit of the present invention.
In the second embodiment, the voltage sampling circuit 100 includes a first voltage dividing unit 101 and a second voltage dividing unit 102.
The voltage input end of the first voltage division unit 101 is connected with the high-voltage positive end of the dc bus, the voltage input end of the second voltage division unit 102 is connected with the high-voltage negative end of the dc bus, and the voltage output end of the first voltage division unit 101 and the voltage output end of the second voltage division unit 102 are respectively connected with the voltage sampling signal input end of the overvoltage comparison circuit 200.
It should be understood that each of the first voltage dividing unit 101 and the second voltage dividing unit 102 includes a number of voltage dividing resistors, where the number of voltage dividing resistors is determined by the voltage level of the dc bus, and the number of voltage dividing resistors in the first voltage dividing unit 101 and the second voltage dividing unit 102 may be the same or different.
It is easy to understand that hvdc_p is the high voltage positive terminal of the dc bus, hvdc_n is the high voltage negative terminal of the dc bus, and the first voltage dividing unit 101 and the second voltage dividing unit 102 jointly achieve voltage dividing action so as to output the sampled voltage of the dc bus to the overvoltage comparing circuit 200, and the voltage sampling signal may include the sampled voltage of the dc bus, that is, the voltage sampling result, so that the voltage accurate sampling is achieved, and meanwhile, the overvoltage protection circuit is ensured to be safely used.
In the second embodiment, the overvoltage comparing circuit 200 includes a third resistor R3, a second capacitor C2, and a comparator A1.
The first end of the third resistor R3 is connected to the voltage sampling signal output end of the voltage sampling circuit 100, the second end of the third resistor R3 is connected to the first end of the second capacitor C2 and the negative input end of the comparator A1, the second end of the second capacitor C2 is grounded, and the output end of the comparator A1 is connected to the overvoltage signal input end of the signal processing circuit 300.
It should be noted that, the voltage sampling signal is sent to the negative input end of the comparator A1 after being filtered, the reference voltage may be input by the positive input end of the comparator A1, the voltage value of the reference voltage may be the minimum value in the voltage-withstanding range of the first reference voltage, that is, the high-voltage component inside the driving motor controller, and the comparator A1 compares the sampling voltage in the filtered voltage sampling signal with the provided reference voltage and outputs the overvoltage signal, that is, the comparison result, to the signal processing circuit 300.
It is readily understood that the third resistor R3 and the second capacitor C2 filter the voltage sample signal. When the sampled voltage of the dc bus is greater than or equal to the first reference voltage, the overvoltage comparing circuit 200 generates an overvoltage signal that may be a low level signal, and when the signal is at a low level, an overvoltage fault occurs, and correspondingly, when the sampled voltage does not exceed the first reference voltage, the overvoltage comparing circuit 200 generates an overvoltage signal that may be a high level inactive signal, and when the signal is at a high level, an overvoltage fault does not occur or the overvoltage fault has disappeared.
In the second embodiment, the signal processing circuit 300 includes a digital isolation circuit 301 and a logic inverting circuit 302 connected in parallel.
The digital isolation circuit 301 is configured to perform signal processing according to the overvoltage signal, and generate an enable signal.
The logic inverting circuit 302 is configured to perform signal processing according to the overvoltage signal, and generate an active short-circuit signal.
The overvoltage signal input end of the digital isolation circuit 301 and the overvoltage signal input end of the logic inverting circuit 302 are respectively connected with the overvoltage signal output end of the overvoltage comparing circuit 200, the low-voltage side enable signal output end of the digital isolation circuit 301 is connected with the low-voltage side enable signal input end of the driving executing circuit 400, and the high-voltage side enable signal output end of the logic inverting circuit 302 is respectively connected with the high-voltage side enable signal input end of the driving executing circuit 400.
Further, the low-voltage side enable signal output end of the digital isolation circuit 301 is connected to the upper bridge wall low-voltage side enable signal input end and the lower bridge wall low-voltage side enable signal input end of the driving execution circuit, respectively, and the high-voltage side enable signal output end of the logic inverting circuit 302 is connected to the upper bridge wall high-voltage side active short-circuit signal input end or the lower bridge wall high-voltage side active short-circuit signal input end of the driving execution circuit.
It is to be understood that the digital isolation circuit 301 may be configured to digitally isolate the overvoltage signal to generate an enable signal acting on the low voltage side of the driving execution circuit 400, and the logic inverting circuit 302 may be configured to perform logic inversion according to the overvoltage signal to generate an active short-circuit signal acting on the high voltage side of the driving execution circuit 400, where the low voltage side enable signal may first enable the enable pin of the driving execution circuit 400 to be in a low level inactive state, and then the driving execution circuit 400 controls the driving motor control system to enter a safe state according to the high voltage side active short-circuit signal, where the priority of the high voltage side active short-circuit signal is higher than the priority of the low voltage side enable signal.
The digital isolation circuit 301 includes a digital isolation chip CP1.
The overvoltage signal input end of the digital isolation chip CP1 is connected with the overvoltage signal output end of the overvoltage comparing circuit 200, and the low-voltage side enable signal output end of the digital isolation chip CP1 is connected with the upper bridge wall low-voltage side enable signal input end and the lower bridge wall low-voltage side enable signal input end of the driving executing circuit respectively, and the enable signal is valid at a high level.
It should be understood that the digital isolation circuit 301 may include a digital isolation chip CP1 and peripheral circuits of the digital isolation chip CP1, where the peripheral circuits assist the digital isolation chip CP1 in operation, and the digital isolation chip CP1 has a digital isolation function. The enable signal generated by the digital isolator chip CP1 may be applied to the low voltage side of the driving execution circuit 400, and if the enable signal is a high level signal, the driving execution circuit 400 may be enabled to enable the driving execution circuit 400 to perform the pwm wave, and if the enable signal is a low level signal, the driving execution circuit 400 may be turned off to disable the driving execution circuit 400 from performing the pwm wave.
In a second embodiment, the logic inverting circuit includes a switching tube; the control end of the switching tube is connected with the overvoltage comparison circuit, the first end of the switching tube is connected with a power supply, and the second end of the switching tube is connected with a direct current bus.
The logic inverting circuit also comprises a delay circuit; the delay circuit comprises a first resistor and a first capacitor;
the first end of the first resistor is connected with the overvoltage comparison circuit, and the second end of the first resistor is connected with the control end of the switching tube; the first end of the second capacitor is connected with the second end of the first resistor, and the second end of the second capacitor is connected with the second end of the switch tube.
In a specific implementation, the logic inverting circuit 302 includes a first resistor R1, a first capacitor C1, a second resistor R2, and a triode T1, where the switching tube may be the triode T1, and the dc bus provides the output voltage of the power supply.
The first end of the first resistor R1 is connected with the overvoltage signal output end of the overvoltage comparing circuit 200, the second end of the first resistor R1 is respectively connected with the first end of the first capacitor C1 and the base of the triode T1, the emitter of the triode T1 is respectively grounded with the second end of the first capacitor C1, the first end of the second resistor R2 is connected with the voltage output end of the power supply, the second end of the second resistor R2 is connected with the collector of the triode T1, and the collector of the triode T1 is connected with the high-voltage side enabling signal input end of the driving executing circuit 400.
It can be understood that the over-voltage signal is filtered and delayed and then sent to the base of the triode T1, and the logic inversion is then performed to send the high-voltage side active short-circuit signal to the enable pin on the high-voltage side of the upper three-bridge (or lower three-bridge) driving execution circuit 400, so that the driving execution circuit 400 can output a high level when the active short-circuit signal generated by the logic inversion circuit 302 acts on the high-voltage side of the driving execution circuit 400. The purpose of the first resistor R1 and the first capacitor C1 is to ensure that the low-voltage side enable signal is already at a low level when the high-voltage side enable signal acts, so as to prohibit the driving execution circuit 400 from executing pulse width modulation wave generation, thereby preventing the upper bridge switching tube and the lower bridge switching tube from being directly damaged. The second resistor R2 is a collector current-limiting resistor of the triode T1, and the power supply provides power supply voltage for the triode T1.
In a specific implementation, the overvoltage comparing circuit 200 further includes a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6.
The first end of the fourth resistor R4 is connected with the voltage output end of the reference voltage source, the second end of the fourth resistor R4 is respectively connected with the positive input end of the comparator A1 and the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected with the output end of the comparator A1, the first end of the sixth resistor R6 is connected with the voltage output end of the power supply, and the second end of the sixth resistor R6 is connected with the output end of the comparator A1.
It can be understood that Vref is a reference voltage, and the reference voltage output by the reference voltage source is connected to the positive input terminal of the comparator A1 through the fourth resistor R4, and the fourth resistor R4 and the fifth resistor R5 jointly determine the threshold voltage amplitude of the comparator A1. VDD is a power supply, and the power supply outputs a power supply voltage to be connected with the output end of the comparator A1 through a sixth resistor R6, wherein the sixth resistor R6 is a pull-up resistor at the output end of the comparator A1.
In the second embodiment, the driving execution circuit 400 includes a driving chip CP2.
The enable signal input end of the driving chip CP2 is connected with the enable signal output end of the signal processing circuit 300, and the control end of the driving chip CP2 is connected with the control end of the driving motor control system.
It is easy to understand that when an overvoltage fault occurs, the driving chips CP2 of all bridge arms firstly make all the enable pins in a low-level invalid state according to the low-voltage side enable signal, the driving chips CP2 prohibit the low-voltage side pulse width modulation from sending a wave command, then control the driving motor control system to enter a safe state according to the high-voltage side enable signal, and enter the safe state within ten microseconds before the voltage of the direct current bus exceeds the maximum value in the voltage-resistant range of the high-voltage component inside the driving motor controller, so as to realize the rapid hardware overvoltage protection.
According to the embodiment, when the vehicle runs at high-speed power generation and the battery main contactor is abnormally disconnected, the driving motor control system is controlled to quickly enter an accurate safety state according to the voltage threshold value and the slope change rule of the direct current bus, the direct current bus voltage in the whole process is always lower than the maximum value of the withstand voltage range of the high-voltage device in the driving motor controller, the high-voltage safety target of the whole vehicle is finally met, the safety of the vehicle and the personnel is ensured, the cost of an overvoltage protection circuit is lower, and the control logic is simple and clear, has higher sampling and control precision, strong reliability and quick response speed, and can meet the rapid overvoltage protection of different permanent magnet synchronous motor counter electromotive forces and power generation systems.
Further, an embodiment of the present invention further provides an overvoltage protection method, referring to fig. 4, fig. 4 is a schematic flow chart of an embodiment of the overvoltage protection method of the present invention, where the overvoltage protection method is applied to the overvoltage protection circuit described above, and the overvoltage protection circuit includes: the device comprises a voltage sampling circuit, an overvoltage comparison circuit, a signal processing circuit and a driving executing circuit.
In this embodiment, the overvoltage protection method includes the following steps:
Step S10: the voltage sampling circuit performs voltage sampling on the direct current bus to generate a voltage sampling signal.
It is easy to understand that when high-speed power generation occurs and the main battery contactor is abnormally disconnected, the overvoltage protection circuit controls the driving motor control system, and the driving motor control system can be switched from a normal operation mode to a safe state (active short-circuit state) within ten microseconds, so that an energy transmission loop between the permanent magnet synchronous motor and the high-voltage direct current bus is rapidly cut off, and the voltages on two sides of the high-voltage direct current bus are controlled within a high-voltage component withstand voltage range, so that a high-voltage safety target of the whole vehicle is met.
It should be understood that the voltage sampling circuit can sample the voltage of the direct current bus in a resistor voltage division mode, the voltage sampling signal can comprise the sampling voltage of the direct current bus, namely a voltage sampling result, the voltage division resistance value can be determined according to the voltage class of the direct current bus, and the overvoltage protection circuit can be safely used while realizing accurate voltage sampling.
Step S20: the overvoltage comparison circuit performs voltage comparison on the voltage sampling signal and a first reference voltage, and generates an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage.
It can be understood that the overvoltage comparing circuit may first filter the voltage sampling signal to remove redundant clutter in the sampling process, and then compare the sampling voltage in the filtered voltage sampling signal with a first provided reference voltage, where the first reference voltage may be a minimum value in a voltage-withstanding range of a high-voltage component inside the driving motor controller.
It is easy to understand that, through voltage comparison, when the sampled voltage of the dc bus is greater than or equal to the first reference voltage, the overvoltage comparing circuit generates an overvoltage signal that can be a low level signal, and when the signal is a low level, the overvoltage comparing circuit generates an overvoltage signal that can be a high level signal, and when the sampled voltage does not exceed the first reference voltage, the signal is a high level, and when the signal is a high level, the overvoltage comparing circuit generates no overvoltage fault or the overvoltage fault has disappeared.
Step S30: and the signal processing circuit performs signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal.
It will be appreciated that the signal processing circuit may signal isolate or logically invert the overvoltage signal. When the generated enabling signal acts on the low-voltage side of the driving execution circuit, the driving execution circuit can be enabled to execute pulse width modulation wave generation by the driving execution circuit if the enabling signal is a high-level signal, and the driving execution circuit can be turned off if the enabling signal is a low-level signal, so that the driving execution circuit is prohibited from executing pulse width modulation wave generation.
It will be appreciated that by logically inverting the over-voltage signal, the driver execution circuit may be caused to output a high level when the generated active short circuit signal acts on the high side of the driver execution circuit. The priority of the high side active short signal (high side enable signal) is higher than the priority of the low side enable signal.
Step S40: and the driving execution circuit controls the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal.
It is easy to understand that the driving execution circuit can make the self-enabling pin in a low-level invalid state according to the low-voltage side enabling signal, then control the driving motor control system to enter a safe state according to the high-voltage side active short-circuit signal, and enter the safe state within ten microseconds before the voltage of the direct-current bus exceeds the maximum value in the voltage-resistant range of the high-voltage component in the driving motor controller, so that the rapid hardware overvoltage protection is realized.
Further, the step S40 includes: and when the sampling voltage is larger than the first reference voltage, the driving execution circuit controls all bridge arms of the motor controller to be turned off according to the enabling signal, and controls the upper bridge arm or the lower bridge arm of the motor controller to be turned on according to the preset delay time of the active short circuit signal.
And in the process that the sampling voltage is reduced from the first reference voltage to the second reference voltage, the upper bridge arm or the lower bridge arm of the motor controller is kept to be conducted.
After the step S40, the method includes: and when the sampling voltage is smaller than the second reference voltage, controlling all bridge arms of the motor controller to be turned off according to the enabling signal, and controlling the upper bridge arm or the lower bridge arm of the motor controller to be turned off according to the preset delay time of the active short circuit signal.
And in the process that the sampling voltage is increased from the second reference voltage to the first reference voltage, keeping all bridge arms of the motor controller to be switched off.
It should be noted that, as shown in fig. 5, fig. 5 is a logic diagram of a switching mode of a safety state according to an embodiment of the overvoltage protection circuit of the present invention. The voltage sample signal is measured on the dc bus. When the sampling voltage in the voltage sampling signal is greater than or equal to U1 (first reference voltage), the overvoltage signal is in a low level, the low-voltage side enabling pins of the driving chips CP2 of all bridge arms are in a low level invalid mode after isolation, and are simultaneously sent to the high-voltage side enabling pins of the driving chips CP2 of the upper three bridges (or the lower three bridges) after short delay and logic inversion, the driving motor controller immediately enters a safe state, namely an ASC state (active short circuit state), and when the sampling voltage is reduced from U1 to U2 (reduced from the first reference voltage to the second reference voltage), the driving motor controller is maintained in the ASC state; when the sampling voltage is smaller than or equal to U2, the overvoltage signal is in a high level, the low voltage side enabling pins of the driving chips CP2 of all bridge arms are in a high level effective mode (at the moment, the driving chips CP2 are forbidden to send pulse width modulation wave-emitting instructions to prevent the driving upper and lower bridges from being directly connected), meanwhile, the overvoltage signal is sent to the high voltage side enabling pins of the driving chips CP2 of the upper and lower three bridges (or the lower three bridges) after being subjected to short delay and logic inversion, the driving motor controller immediately exits an ASC state and enters a FREEWHEELING state, namely a follow current state, and when the direct current bus voltage is increased from U2 to U1 (the second reference voltage is increased to the first reference voltage), the motor controller is maintained in a FREEWHEELING state in a safe state, so that the safe state mode is randomly switched along with the change of the direct current bus voltage and has high anti-interference capability. Wherein SAFE STATE represents a safe state, udc represents a direct current bus voltage, U1 and U2 of the direct current bus voltage can be two different reference voltages at two ends of a direct current bus capacitor of a driving motor controller, and the amplitude of the direct current bus voltage U1 is larger than or equal to that of the direct current bus voltage U2; the threshold width between the dc bus voltage U1 and the dc bus voltage U2 can be adjusted by changing the resistance values of the second resistor R2 and the third resistor R3.
According to the embodiment, the voltage sampling circuit is used for sampling the voltage of the direct current bus to generate a voltage sampling signal, the overvoltage comparison circuit is used for comparing the voltage sampling signal with the first reference voltage, when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage, an overvoltage signal is generated, the signal processing circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal, and the driving execution circuit is used for controlling the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal. According to the embodiment, the direct current bus is subjected to voltage sampling, and when the sampling voltage of a voltage sampling signal exceeds the first reference voltage, the driving motor control system is controlled to enter a safe state, so that the rapid hardware overvoltage protection is realized.
In addition, the embodiment of the invention also provides a motor controller which comprises the overvoltage protection circuit or is applied to the overvoltage protection method.
Because the motor controller adopts all the technical schemes of all the embodiments, the motor controller at least has all the beneficial effects brought by the technical schemes of the embodiments, and the description is omitted herein.
It should be understood that the foregoing is illustrative only and is not limiting, and that in specific applications, those skilled in the art may set the invention as desired, and the invention is not limited thereto.
It should be noted that the above-described working procedure is merely illustrative, and does not limit the scope of the present invention, and in practical application, a person skilled in the art may select part or all of them according to actual needs to achieve the purpose of the embodiment, which is not limited herein.
In addition, technical details not described in detail in the present embodiment can be referred to an overvoltage protection circuit, an overvoltage protection method and a motor controller provided in any embodiment of the present invention, which are not described herein.
Furthermore, it should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. Read Only Memory)/RAM, magnetic disk, optical disk) and including several instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present invention.
The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.
Claims (10)
1. The overvoltage protection circuit is characterized by comprising a voltage sampling circuit, an overvoltage comparison circuit, a signal processing circuit and a driving execution circuit which are connected in sequence;
The voltage sampling circuit is used for sampling the voltage of the direct current bus and generating a voltage sampling signal;
the overvoltage comparison circuit is used for comparing the voltage sampling signal with a first reference voltage, and generating an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage;
the signal processing circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal;
And the driving execution circuit is used for controlling the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal.
2. The overvoltage protection circuit of claim 1, wherein the signal processing circuit comprises a digital isolation circuit and a logic inverting circuit connected in parallel with each other;
the digital isolation circuit is used for performing signal processing according to the overvoltage signal to generate an enabling signal;
and the logic inverting circuit is used for performing signal processing according to the overvoltage signal to generate an active short-circuit signal.
3. The overvoltage protection circuit of claim 2, wherein the logic inverting circuit comprises a switching tube;
The control end of the switching tube is connected with the overvoltage comparison circuit, the first end of the switching tube is connected with a power supply, and the second end of the switching tube is connected with a direct current bus.
4. The overvoltage protection circuit of claim 3 wherein said logic inverting circuit further comprises a delay circuit.
5. The overvoltage protection circuit of claim 4 wherein said delay circuit includes a first resistor and a first capacitor;
The first end of the first resistor is connected with the overvoltage comparison circuit, and the second end of the first resistor is connected with the control end of the switching tube; the first end of the first capacitor is connected with the second end of the first resistor, and the second end of the first capacitor is connected with the second end of the switch tube.
6. The overvoltage protection circuit of claim 2, wherein the overvoltage signal input of the digital isolation circuit and the overvoltage signal input of the logic inverting circuit are respectively connected with the overvoltage signal output of the overvoltage comparing circuit, the low-voltage side enable signal output of the digital isolation circuit is connected with the low-voltage side enable signal input of the driving executing circuit, and the high-voltage side enable signal output of the logic inverting circuit is respectively connected with the high-voltage side enable signal input of the driving executing circuit.
7. An overvoltage protection method, characterized in that the overvoltage protection method is applied to an overvoltage protection circuit according to any one of claims 1 to 6, the overvoltage protection circuit comprising: the overvoltage protection method comprises the following steps of:
The voltage sampling circuit performs voltage sampling on the direct current bus to generate a voltage sampling signal;
The overvoltage comparison circuit performs voltage comparison on the voltage sampling signal and a first reference voltage, and generates an overvoltage signal when the sampling voltage of the voltage sampling signal is greater than or equal to the first reference voltage;
The signal processing circuit performs signal processing according to the overvoltage signal to generate an enabling signal and an active short-circuit signal;
And the driving execution circuit controls the motor controller to enter a safe state according to the enabling signal and the active short-circuit signal.
8. The method of claim 7, wherein the driving execution circuit controls the motor controller to enter a safe state according to the enable signal and the active short circuit signal, comprising:
When the sampling voltage is larger than the first reference voltage, the driving execution circuit controls all bridge arms of the motor controller to be turned off according to the enabling signal, and controls the upper bridge arm or the lower bridge arm of the motor controller to be turned on according to the preset delay time of the active short circuit signal;
And in the process that the sampling voltage is reduced from the first reference voltage to the second reference voltage, the upper bridge arm or the lower bridge arm of the motor controller is kept to be conducted.
9. The method of claim 8, wherein the maintaining the upper or lower leg of the motor controller on during the step of the sampling voltage falling from the first reference voltage to the second reference voltage comprises:
When the sampling voltage is smaller than the second reference voltage, controlling all bridge arms of the motor controller to be turned off according to the enabling signal, and controlling the upper bridge arm or the lower bridge arm of the motor controller to be turned off according to the preset delay time of the active short circuit signal;
and in the process that the sampling voltage is increased from the second reference voltage to the first reference voltage, keeping all bridge arms of the motor controller to be switched off.
10. A motor controller comprising an overvoltage protection circuit according to any one of claims 1 to 6 or being applied to an overvoltage protection method according to any one of claims 7 to 9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111096382.9A CN113765466B (en) | 2021-09-17 | 2021-09-17 | Overvoltage protection circuit, overvoltage protection method and motor controller |
| PCT/CN2022/083785 WO2023040236A1 (en) | 2021-09-17 | 2022-03-29 | Overvoltage protection circuit, overvoltage protection method, and motor controller |
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| CN202111096382.9A CN113765466B (en) | 2021-09-17 | 2021-09-17 | Overvoltage protection circuit, overvoltage protection method and motor controller |
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| CN113765466B (en) * | 2021-09-17 | 2024-05-24 | 苏州汇川联合动力系统股份有限公司 | Overvoltage protection circuit, overvoltage protection method and motor controller |
| CN115499573A (en) * | 2022-09-19 | 2022-12-20 | 杭州海康威视数字技术股份有限公司 | Video camera |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19980065949A (en) * | 1997-01-17 | 1998-10-15 | 김광호 | Control device of 3-phase brushless motor drive circuit |
| JP2005073423A (en) * | 2003-08-26 | 2005-03-17 | Matsushita Electric Ind Co Ltd | Motor driving device |
| JP2016025776A (en) * | 2014-07-22 | 2016-02-08 | アイシン・エィ・ダブリュ株式会社 | Control device for rotary electric machine |
| CN108565839A (en) * | 2018-03-08 | 2018-09-21 | 精进电动科技股份有限公司 | A kind of IGBT drive circuit and electric machine controller of electric machine controller |
| CN108696226A (en) * | 2018-06-01 | 2018-10-23 | 阳光电源股份有限公司 | A kind of electric machine controller |
| CN110518809A (en) * | 2019-08-29 | 2019-11-29 | 海信（山东）空调有限公司 | A kind of frequency changer controller and method, air-conditioning |
| CN111092414A (en) * | 2019-12-25 | 2020-05-01 | 深圳市英威腾电动汽车驱动技术有限公司 | New energy automobile and overvoltage protection circuit and overvoltage protection method thereof |
| CN112073628A (en) * | 2019-06-10 | 2020-12-11 | 海信视像科技股份有限公司 | Motor control circuit, driving device and display device |
| CN112104109A (en) * | 2020-09-11 | 2020-12-18 | 浙江大学 | Controller circuit for wireless power transmission system |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004215328A (en) * | 2002-12-26 | 2004-07-29 | Aisin Aw Co Ltd | Control device and method for motor operated drive, and its program |
| CN102611372B (en) * | 2012-03-09 | 2014-12-24 | 北京经纬恒润科技有限公司 | Method and system for acquiring feedback current of driver of stepping motor |
| CN204886147U (en) * | 2015-08-31 | 2015-12-16 | 国网河南省电力公司电力科学研究院 | Adjustable intermittence time's current foldback circuit |
| CN109167553A (en) * | 2018-09-30 | 2019-01-08 | 合肥巨动力系统有限公司 | A kind of electric machine control system security mechanism implementation method based on MCU+CPLD framework |
| CN113765466B (en) * | 2021-09-17 | 2024-05-24 | 苏州汇川联合动力系统股份有限公司 | Overvoltage protection circuit, overvoltage protection method and motor controller |
-
2021
- 2021-09-17 CN CN202111096382.9A patent/CN113765466B/en active Active
-
2022
- 2022-03-29 WO PCT/CN2022/083785 patent/WO2023040236A1/en unknown
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19980065949A (en) * | 1997-01-17 | 1998-10-15 | 김광호 | Control device of 3-phase brushless motor drive circuit |
| JP2005073423A (en) * | 2003-08-26 | 2005-03-17 | Matsushita Electric Ind Co Ltd | Motor driving device |
| JP2016025776A (en) * | 2014-07-22 | 2016-02-08 | アイシン・エィ・ダブリュ株式会社 | Control device for rotary electric machine |
| CN108565839A (en) * | 2018-03-08 | 2018-09-21 | 精进电动科技股份有限公司 | A kind of IGBT drive circuit and electric machine controller of electric machine controller |
| CN108696226A (en) * | 2018-06-01 | 2018-10-23 | 阳光电源股份有限公司 | A kind of electric machine controller |
| CN112073628A (en) * | 2019-06-10 | 2020-12-11 | 海信视像科技股份有限公司 | Motor control circuit, driving device and display device |
| CN110518809A (en) * | 2019-08-29 | 2019-11-29 | 海信（山东）空调有限公司 | A kind of frequency changer controller and method, air-conditioning |
| CN111092414A (en) * | 2019-12-25 | 2020-05-01 | 深圳市英威腾电动汽车驱动技术有限公司 | New energy automobile and overvoltage protection circuit and overvoltage protection method thereof |
| CN112104109A (en) * | 2020-09-11 | 2020-12-18 | 浙江大学 | Controller circuit for wireless power transmission system |
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| CN113765466A (en) | 2021-12-07 |
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