WO2022022733A1 - 一种无线电励磁系统、检测方法及电动汽车 - Google Patents

一种无线电励磁系统、检测方法及电动汽车 Download PDF

Info

Publication number
WO2022022733A1
WO2022022733A1 PCT/CN2021/109959 CN2021109959W WO2022022733A1 WO 2022022733 A1 WO2022022733 A1 WO 2022022733A1 CN 2021109959 W CN2021109959 W CN 2021109959W WO 2022022733 A1 WO2022022733 A1 WO 2022022733A1
Authority
WO
WIPO (PCT)
Prior art keywords
excitation
transformer
current
circuit
controller
Prior art date
Application number
PCT/CN2021/109959
Other languages
English (en)
French (fr)
Inventor
舒为亮
范永滔
陈双全
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to EP21851108.7A priority Critical patent/EP4181389A4/en
Publication of WO2022022733A1 publication Critical patent/WO2022022733A1/zh

Links

Images

Classifications

    • 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
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
    • 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
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • 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
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • H02P25/03—Synchronous motors with brushless excitation
    • 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
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/16—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the circuit arrangement or by the kind of wiring
    • H02P25/18—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the circuit arrangement or by the kind of wiring with arrangements for switching the windings, e.g. with mechanical switches or relays
    • 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
    • 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
    • H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
    • H02P9/14—Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field
    • 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
    • H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
    • H02P2207/05—Synchronous machines, e.g. with permanent magnets or DC excitation

Definitions

  • the present application relates to the field of electronic power technology, and in particular, to a radio excitation system, a detection method and an electric vehicle.
  • the driving motor of the electric vehicle is a permanent magnet synchronous motor
  • the motor runs at a high speed
  • a high-voltage back EMF will be generated on the stator winding of the motor.
  • the speed of the motor is further increased, it may cause damage to the first controller.
  • the magnetic field generated by the permanent magnet material of the motor rotor cannot be adjusted, only the current of the d-axis on the stator side of the motor (in the same direction as the magnetic field of the motor rotor) can be adjusted to change the air gap magnetic field, thereby reducing the back EMF of the motor stator winding, but when increasing When the d-axis current is used, the efficiency of the motor at high speed will be significantly reduced.
  • a radio excitation synchronous motor (hereinafter referred to as an electric excitation motor) can be used.
  • the radio excitation is to supply power to the excitation winding of the motor rotor through the excitation transformer in a wireless manner.
  • a magnetic field with a controllable size is generated to replace the constant magnetic field of the permanent magnet material of the electronic rotor, so that the size of the magnetic field of the motor rotor can be controlled.
  • the present application provides a radio excitation system, a detection method and an electric vehicle, which can detect electrical parameters of the radio excitation system.
  • the present application provides a wireless excitation system, comprising: an excitation transformer, an excitation rectifier circuit, an electric excitation motor, a detection circuit, a first power conversion circuit, a second power conversion circuit, a first controller, and a second control device.
  • the input end of the first power conversion circuit is connected to the power supply, the output end of the first power conversion circuit is connected to the stator winding of the electric excitation motor; the input end of the second power conversion circuit is connected to the power supply, and the output end of the second power conversion circuit is connected to the excitation transformer.
  • the excitation transformer is used to transfer the energy required by the excitation winding of the electric excitation motor from the stator to the rotor;
  • the excitation rectifier circuit is used to convert the alternating current received by the secondary side of the excitation transformer into direct current and then transmit it to the excitation winding;
  • a controller is used to control the first power conversion circuit to inject current excitation into the stator winding to generate current on the excitation winding;
  • the detection circuit is used to acquire the response signal of the primary side of the excitation transformer and send it to the second controller;
  • the current generated on the excitation winding short-circuits the secondary side of the excitation transformer, and when the current generated on the excitation winding makes the secondary side of the excitation transformer open, the second power conversion circuit is controlled to inject pulse current excitation into the primary side of the excitation transformer, and use The electrical parameters of the excitation transformer are determined in response to the signal.
  • the system is excited by injecting different currents into the windings of the stator of the electric excitation motor, so that currents are generated on the excitation windings.
  • the direction of the current in the excitation windings will affect the load characteristics of the rectifier bridge on the rotor side of the motor, thereby making the secondary side of the excitation transformer.
  • Two different load states of short circuit and open circuit can be presented.
  • the second controller detects the response signal corresponding to the excitation of the pulse current on the primary side of the excitation transformer through the detection circuit, and then determines the electrical parameters of the excitation transformer according to the response signal.
  • the electrical parameters include a leakage inductance value and an inductance value of the excitation inductance
  • the second controller uses the resonance frequency of the response signal when the secondary side of the excitation transformer is short-circuited to obtain the excitation transformer.
  • the leakage inductance value of the primary side and the leakage inductance value of the secondary side of the excitation transformer are obtained; the inductance value of the excitation inductance of the excitation transformer is obtained by using the resonance frequency of the response signal when the secondary side of the excitation transformer is disconnected.
  • the second controller can obtain the leakage inductance value of the primary side, the leakage inductance value of the secondary side and the inductance value of the excitation inductance of the excitation transformer according to the different response signals of the primary side when the secondary side is in two different load states of short circuit and open circuit.
  • the leakage inductance value of the primary side of the excitation transformer is generally equal to the leakage inductance value of the secondary side.
  • the second controller is further configured to determine that there is a fault in the wireless excitation system when the absolute value of the difference between the electrical parameter and the preset electrical parameter is greater than the preset threshold.
  • the second controller of the system can use the electrical parameter to determine whether there is a fault in the wireless excitation system.
  • the second controller is further configured to use the response signal to perform fault detection on the radio excitation system.
  • the response signal obtained in the system of the present application is the response of the primary side to the pulse current excitation when the secondary side of the excitation transformer is in different load characteristics
  • the response signal can also be used to detect whether there is a fault in the radio excitation system.
  • the second controller is specifically configured to: when the frequency of the response signal is lower than the preset frequency range, determine that the diode of the excitation rectifier circuit has an open-circuit fault; When the frequency is higher than the preset frequency range, it is determined that the diode of the excitation rectifier circuit has a short-circuit fault; when the amplitude of the response signal is higher than the preset amplitude range, it is determined that the capacitance value of the output capacitor of the excitation rectifier circuit is abnormal.
  • the first controller controls the first power conversion circuit to inject gradually decreasing d-axis current excitation into the stator winding of the electric excitation motor within the first preset time, so as to The secondary side of the excitation transformer is short-circuited, and the d-axis is consistent with the magnetic field direction of the rotor; the first power conversion circuit is controlled to inject gradually increasing d-axis current excitation into the stator winding of the electric excitation motor within the second preset time, so as to excite the d-axis. Short circuit the secondary side of the excitation transformer.
  • the first preset time is greater than the duration of the pulse current excitation, so as to ensure that the secondary side of the excitation transformer is in a short-circuit state during the duration of the pulse current excitation.
  • the second preset time is greater than the duration of the pulse current excitation, so as to ensure that the secondary side of the excitation transformer is in an open-circuit state within the duration of the pulse current excitation.
  • the first controller is further configured to send a control command to the second controller after injecting current excitation into the stator winding of the electric excitation motor, where the control command is used to instruct the second controller
  • the controller controls the second power conversion circuit to inject pulse current excitation into the primary side of the excitation transformer. That is, the first controller notifies the second controller to start detecting the electrical parameters.
  • the detection circuit specifically includes a current transformer and a signal processing circuit, the primary winding of the current transformer is connected to the primary side of the excitation transformer, and the secondary winding of the current transformer is connected to the primary side of the excitation transformer. Connect the signal processing circuit.
  • the signal processing circuit is used for processing the signal collected by the current transformer to obtain a response signal, and sending the response signal to the second controller.
  • the first controller and the second controller are integrated into one microcontroller unit MCU.
  • the first controller and the second controller may also be integrated into different microcontroller units, respectively.
  • the present application also provides a method for detecting a radio excitation system, which is applied to the radio excitation system provided by the above implementation manner, and the method includes:
  • controlling the first power conversion circuit to inject current excitation into the stator winding of the electric excitation motor, so as to generate current on the excitation winding
  • the second power conversion circuit is controlled to inject pulse current excitation to the primary side of the excitation transformer, And use the response signal of the primary side of the excitation transformer to determine the electrical parameters of the excitation transformer.
  • the electrical parameters include a leakage inductance value and an inductance value of the excitation inductance
  • the determining the electrical parameters of the excitation transformer by using the response signal of the primary side of the excitation transformer specifically includes:
  • the inductance value of the excitation inductance of the excitation transformer is obtained by using the resonance frequency of the response signal when the secondary side of the excitation transformer is disconnected.
  • the method further includes: when the absolute value of the difference between the electrical parameter and the preset electrical parameter is greater than a preset threshold, determining that the radio excitation system is faulty.
  • the method further includes: using the response signal to perform fault detection on the radio excitation system.
  • the response signal is used to perform fault detection on the radio excitation system, which specifically includes:
  • the diode of the excitation rectifier circuit When the frequency of the response signal is lower than the preset frequency range, it is determined that the diode of the excitation rectifier circuit has an open-circuit fault; when the frequency of the response signal is higher than the preset frequency range, it is determined that the diode of the excitation rectifier circuit has a short-circuit fault; When the amplitude is higher than the preset amplitude range, it is determined that the capacitance value of the output capacitor of the excitation rectifier circuit is abnormal.
  • control of the first power conversion circuit to inject current excitation into the stator winding of the motor to generate current on the excitation winding specifically includes:
  • the first power conversion circuit is controlled to inject gradually decreasing d-axis current excitation into the stator winding of the electric excitation motor within a first preset time, so as to generate current on the excitation winding and short-circuit the secondary side of the excitation transformer,
  • the d-axis is consistent with the magnetic field direction of the rotor;
  • Controlling the first power conversion circuit to inject gradually increasing d-axis current excitation into the stator winding of the electric excitation motor within a second preset time, so as to generate current on the excitation winding and short-circuit the secondary side of the excitation transformer;
  • the first preset time and the second preset time are greater than the duration of the pulse current excitation.
  • the present application also provides an electric vehicle, the electric vehicle includes the radio excitation system provided by any one of the above implementation manners, and also includes a power battery pack, which is used for powering the radio excitation system.
  • the first controller of the wireless excitation system controls the first power conversion circuit to inject current excitation into the windings of the stator of the electric excitation motor, so as to generate current on the excitation winding, thereby changing the load characteristics of the secondary side of the excitation transformer.
  • the second controller controls the second power conversion circuit to inject pulse current excitation into the primary side of the excitation transformer when the current generated on the excitation winding short-circuits the secondary side of the excitation transformer, and when the current generated on the excitation winding makes the secondary side of the excitation transformer short-circuit When the side is disconnected, the second power conversion circuit is controlled to inject pulse current excitation into the primary side of the excitation transformer.
  • the pulse current excitation causes the primary side of the excitation transformer to generate a response signal corresponding to the pulse current excitation.
  • the detection circuit obtains the response signal of the primary side of the excitation transformer, and then transmits it to the second controller. Because the load characteristics of the secondary side of the excitation transformer are different, the obtained response signal is different, and the second controller can determine according to the received response signal.
  • the electrical parameters of the excitation transformer to facilitate fault diagnosis.
  • Fig. 1 is the schematic diagram of the radio excitation system
  • FIG. 2 is a schematic diagram of a radio excitation system provided by an embodiment of the present application.
  • FIG. 3 is a schematic diagram of another radio excitation system provided by an embodiment of the present application.
  • FIG. 4 is a schematic diagram of a signal timing sequence provided by an embodiment of the present application.
  • FIG. 5 is a schematic diagram of a pulse current excitation and a response signal provided by an embodiment of the present application
  • FIG. 6 is a flowchart of a method for detecting a radio excitation system provided by an embodiment of the present application
  • FIG. 7 is a flowchart of another method for detecting a radio excitation system provided by an embodiment of the present application.
  • FIG. 8 is a schematic diagram of an electric vehicle according to an embodiment of the present application.
  • FIG. 1 the figure is a schematic diagram of a wireless excitation system.
  • the wireless excitation system includes: a DC power supply 110, an excitation controller 120, a DC-AC converter 121, a compensation circuit 130, an excitation transformer 140, a motor controller 150, a power circuit 151, a motor stator winding 160, a motor rotor 210, and the like.
  • the DC power supply 110 provides DC power for the excitation controller 120 and the motor controller 150.
  • the DC power supply 110 may be a vehicle power battery pack.
  • the DC-AC converter 121 converts the DC power obtained from the DC power source 110 into AC power, and then supplies the AC power to the excitation transformer 140 .
  • the compensation network 130 mainly includes an inductor and a capacitor for matching the impedance relationship required by the power conversion circuit. In some embodiments, the compensation network 130 may also be absent.
  • the excitation transformer 140 includes an excitation transformer primary 141 and an excitation transformer secondary 211 .
  • the excitation transformer primary 141 is relatively stationary with the motor stator in the electric excitation motor, and the excitation transformer secondary 211 rotates together with the motor rotor 210 at high speed.
  • the excitation energy required by the motor rotor 210 is sent from the motor stator side to the motor rotor side by the excitation transformer 140 .
  • the motor controller 150 is used to control the power circuit 151 to generate alternating current with controllable frequency and amplitude, and supply it to the stator winding 160 of the motor.
  • the motor controller 150 and the excitation controller 120 may be integrated together, for example, integrated on the same MCU (Micro Control Unit, micro processing unit), or may be independently provided on different MCUs. When set independently of each other, there is a signal interaction between the two, and the motor controller 150 sends its excitation current demand to the excitation controller 120 .
  • MCU Micro Control Unit, micro processing unit
  • the stator winding 160 of the motor uses the motor controller 150 to inject alternating current with controllable frequency and amplitude to generate a rotating magnetic field, which drives the motor rotor 210 to rotate synchronously.
  • the motor rotor 210 at least includes an excitation transformer secondary side 211 , an excitation rectifier circuit 212 and an excitation winding 213 .
  • the secondary side 211 of the excitation transformer is used to receive the energy transmitted by the primary side 141 of the excitation transformer
  • the excitation rectifier circuit 212 converts the alternating current received by the secondary side 211 of the excitation transformer into direct current
  • the direct current flowing on the excitation winding 213 generates a DC magnetic field.
  • the excitation transformer 140 is a type of resolver, there are certain parameter deviations and installation errors, which may lead to changes in the actual electrical parameters.
  • the electric excitation motor and the excitation transformer 140 are assembled, it is difficult to use the traditional method to detect the electrical parameters again. parameters, it is inconvenient to carry out fault judgment.
  • an auxiliary power supply, a detection circuit and a communication circuit can be provided on the motor rotor 210 side, and information such as voltage and current on the motor rotor side can be transmitted to the stator side of the motor by wireless communication, so as to realize the detection of the excitation current.
  • the embodiments of the present application provide a radio excitation system, a detection method and an electric vehicle, by injecting different current excitations into the windings of the stator of the electric excitation motor, so that currents are generated on the excitation windings, and the current of the excitation windings
  • the direction of the rectifier bridge will affect the load characteristics of the rectifier bridge on the rotor side of the motor, so that the secondary side of the excitation transformer can present two different load states of short circuit and open circuit.
  • a pulse current is injected into the primary side of the excitation transformer for excitation.
  • the response signal corresponding to the pulse current excitation on the primary side of the excitation transformer is detected by the detection circuit, and the electrical parameters of the excitation transformer are determined according to the response signal.
  • connection should be understood in a broad sense.
  • connection may be a fixed connection, a detachable connection, or an integral body; it may be a direct connection, or a Indirect connections can be made through an intermediary.
  • FIG. 2 this figure is a schematic diagram of a radio excitation system provided by an embodiment of the present application.
  • the wireless excitation system includes: a second controller 120A, an excitation transformer 140, an excitation rectifier circuit 212, an electric excitation motor, a second power conversion circuit 121A, a first power conversion circuit 151A, a first controller 150A, and a Detection circuit 170 .
  • the electric excitation motor includes a motor stator and a motor rotor 210 .
  • the motor stator is a stationary part of the motor, which mainly includes an iron core (not shown in the figure), a stator winding 160 and a frame (not shown in the figure).
  • the motor rotor is a rotating part in the motor, which is used to convert electrical energy into mechanical energy, and includes at least the secondary side 211 of the excitation transformer, the excitation rectifier circuit 212 and the excitation winding 213.
  • the excitation rectifier circuit 212 is taken as an example of a full-bridge rectifier circuit, and each half-bridge arm of the full-bridge rectifier circuit includes a diode.
  • the primary side of the excitation transformer 140 is relatively stationary with the stator of the electric excitation motor, and the secondary side of the excitation transformer 140 is relatively stationary with the rotor of the electric excitation motor.
  • the field transformer 140 is used to transfer the energy required by the field windings of the electric field motor from the motor stator to the motor rotor.
  • the input end of the second power conversion circuit 121A is connected to the power source 110, and the output end of the second power conversion circuit 121A is connected to the primary side of the excitation transformer.
  • the second power conversion circuit 121A is used for converting direct current to alternating current, that is, the DC-AC converter 121 in FIG. 1 .
  • the input end of the first power conversion circuit 151A is connected to the power source 110 , and the output end of the first power conversion circuit 151A is connected to the stator winding 160 of the electric excitation motor.
  • the first power conversion circuit 151A is used for converting direct current to alternating current, that is, the power circuit 151 in FIG. 1 .
  • the first controller 150A is configured to control the first power conversion circuit 151A to inject current excitation into the stator winding of the motor, so as to generate current on the excitation winding 213 .
  • the specific description is given below. For the convenience of description, in the following description of the present application, the current direction along the circuit is clockwise as positive, and counterclockwise as negative.
  • the first controller 150A controls the first power conversion circuit 151A to inject a uniformly increased excitation current into the stator winding of the motor, the excitation winding 213 will generate a negative current (opposite to the direction of if shown in the figure), and the negative current will be generated.
  • the current makes the excitation winding load irrelevant to the output of the excitation rectifier circuit 212, thus causing the excitation rectifier circuit 212 to be open for a short time.
  • the current generated on the excitation winding will make the secondary side of the excitation transformer present two states of short circuit and open circuit, that is, to change the load characteristics of the secondary side of the excitation transformer.
  • the second controller 120A controls the second power conversion circuit 121A to short-circuit the secondary side 211 of the excitation transformer when the current generated by the excitation winding 213 short-circuits the secondary side 211 of the excitation transformer, and when the current generated by the excitation winding 213 opens the secondary side 211 of the excitation transformer.
  • the primary side of the excitation transformer is injected with pulse current excitation.
  • the detection circuit 170 is used to acquire the response signal of the primary side of the excitation transformer and transmit it to the second controller 120A.
  • the load characteristics of the secondary side of the excitation transformer are different, which will cause the primary side to generate different response signals.
  • the second controller 120A can determine the electrical parameters of the excitation transformer according to the detected response signal and the known device parameters in the circuit, for example, the leakage inductance and excitation inductance of the excitation transformer can be determined, that is, the electrical parameters of the excitation transformer can be determined. parameter detection.
  • the first controller of the wireless excitation system controls the first power conversion circuit to inject current excitation into the windings of the stator of the motor, so as to generate current on the excitation windings, thereby changing the auxiliary power of the excitation transformer. edge load characteristics.
  • the second controller controls the second power conversion circuit to inject into the primary side of the excitation transformer when the current generated by the excitation winding short-circuits the secondary side of the excitation transformer, and when the current generated by the excitation winding makes the secondary side of the excitation transformer open circuit Pulse current excitation.
  • the pulse current excitation causes the primary side of the excitation transformer to generate a response signal corresponding to the pulse current excitation.
  • the detection circuit obtains the response signal of the primary side of the excitation transformer, and then transmits it to the second controller. Because the load characteristics of the secondary side of the excitation transformer are different, the obtained response signal is different, and the second controller can determine according to the received response signal. Electrical parameters of the excitation transformer.
  • the hardware cost of the wireless excitation system provided by the embodiments of the present application is lower, and the wireless excitation system can be used on the stator side of the electric excitation motor. To complete the detection, there is no need to increase the hardware circuit on the rotor side of the electric excitation motor, thus improving the reliability.
  • Embodiment 2 is a diagrammatic representation of Embodiment 1:
  • this figure is a schematic diagram of another radio excitation system provided by an embodiment of the present application.
  • the compensation network 130 includes an inductor Lr and a capacitor Cr.
  • the inductance value of the inductor Lr and the capacitance value of the capacitor Cr are known parameters during system design. The description is given by taking the second power conversion circuit 121A as the DC-AC converter 121 as an example.
  • the excitation transformer 140 is equivalently processed in FIG. 3 , and its equivalent model includes: the leakage inductance L lk1 of the primary side, the leakage inductance L lk2 of the secondary side, the excitation inductance L m and the ideal transformer Tr .
  • the detection circuit 170 including a current transformer CT and a signal processing circuit as an example for description.
  • the current transformer CT is used to detect the current response ir of the primary side of the excitation transformer, and the obtained electrical signal is V ir ;
  • the signal processing circuit is used to process the signal collected by the current transformer to obtain the response signal, and the said A response signal is sent to the second controller.
  • the current direction is clockwise along the circuit as positive, and counterclockwise as negative.
  • this figure is a schematic diagram of a signal timing sequence provided by an embodiment of the present application.
  • the first controller 150A controls the first power conversion circuit 151A to inject the d -axis current excitation into the stator winding 160 of the motor, and the d-axis is consistent with the magnetic field direction of the rotor.
  • id gradually decreases over time, in some embodiments, it can be taken to satisfy Negative and constant, id is injected into the stator winding 160 and then held constant, so that the excitation winding 213 generates a forward current if, corresponding to the time period t1-t2 in FIG. 4 (the first preset time).
  • the ideal transformer Tr When the secondary side of the ideal transformer Tr (that is, the secondary side of the excitation transformer 140) is short-circuited, the ideal transformer Tr is equivalent to the leakage inductance Llk2 of the secondary side first in parallel with the excitation inductance Lm , and the leakage inductance Llk1 of the primary side is connected in series. . And since the inductance value of the excitation inductance L m is much larger than the inductance value of the secondary leakage inductance L lk2 , the inductance value of the two in parallel is about the inductance value of the secondary leakage inductance L lk2 . Therefore, the inductance connected to the excitation transformer 140 is equivalent to (L lk1 +L lk2 ), and the resonant frequency f 1 of the primary side of the ideal transformer Tr is:
  • the second controller 120A injects pulse current excitation into the primary side of the ideal transformer Tr.
  • the second controller 120A injects pulse current excitation into the primary side of the ideal transformer Tr by controlling the working state of the DC-AC converter 121 .
  • the pulsed current excitation produces a corresponding voltage V AB at the output of the DC-AC converter 121 .
  • the duration of the pulse current excitation is shorter than the short-circuit time of the secondary side of the ideal transformer Tr, and the embodiment of the present application does not specifically limit the duration of the pulse current excitation.
  • the t1-t2 time period can be relatively long, such as 20 times the duration of the pulse current excitation, to ensure that the secondary side of the ideal transformer Tr is in a short-circuit state during the pulse current excitation duration.
  • the first controller 150A may send a detection command to the second controller 120A to notify the second controller 120A to send a detection instruction to the ideal transformer.
  • the primary side of Tr is injected with pulse current excitation.
  • the pulse current excitation will cause natural resonance to occur on the capacitor Cr and the inductor (L r +L lk1 +L lk2 ) of the ideal transformer Tr, and then the primary side of the ideal transformer Tr will generate a corresponding response signal ir corresponding to the pulse current excitation, and the response signal i
  • the waveform of r is embodied as the waveform of damped oscillation.
  • the high-frequency AC response signal ir circulates in the primary winding of the ideal transformer Tr. After passing through the detection circuit 170, a signal V ir reflecting the current magnitude and phase of the response signal ir can be obtained and sent to the second controller 120A .
  • the second controller 120A obtains the frequency of the signal V ir , that is, obtains the resonant frequency f 1 , and since the inductance value of the inductor Lr and the capacitance value of the capacitor Cr are known parameters, the leakage inductance L lk1 and The leakage inductance L lk2 of the secondary side is the same, so the leakage inductance L lk1 of the primary side and the leakage inductance L lk2 of the secondary side can be determined according to equation (1).
  • the first controller 150A controls the first power conversion circuit 151A to change the d -axis current injected into the stator winding of the electric excitation motor to excite id , so that id gradually increases with time.
  • the is a positive value and remains unchanged, corresponding to the time period t3-t4 (second preset time) in FIG. 4 .
  • the excitation winding 213 generates a negative current if (in the opposite direction to if shown in FIG. 3 ), the diode of the excitation rectifier circuit 212 is reversely turned off, and the excitation rectifier circuit 212 is in an open circuit (ie, an open circuit) during this period of time. state.
  • the ideal transformer Tr When the secondary side of the ideal transformer Tr (ie, the secondary side of the excitation transformer 140 ) is disconnected, the ideal transformer Tr is equivalent to the leakage inductance Llk1 of the primary side and the excitation inductance Lm in series. Therefore, the inductance connected to the excitation transformer 140 is equivalent to (L lk1 +L m ), and the resonant frequency f 2 of the primary side of the ideal transformer Tr is:
  • the second controller 120A injects pulse current excitation into the primary side of the ideal transformer Tr.
  • the second controller 120A injects pulse current excitation into the primary side of the ideal transformer Tr by controlling the working state of the DC-AC converter 121 .
  • the pulsed current excitation produces a corresponding voltage V AB at the output of the DC-AC converter 121 .
  • the duration of the pulse current excitation is shorter than the open-circuit time of the secondary side of the ideal transformer Tr, and the embodiment of the present application does not specifically limit the duration of the pulse current excitation.
  • the t3-t4 time period can be relatively long, such as 20 times the duration of the pulse current excitation, to ensure that the secondary side of the ideal transformer Tr is in an open circuit state during the pulse current excitation duration.
  • the pulse current excitation injected by the second controller 120A during the open circuit period of the secondary side of the ideal transformer Tr may be the same as or different from the pulse current excitation injected during the short circuit period of the secondary side of the ideal transformer Tr, which is not specifically limited in the embodiment of the present application.
  • the pulse current excitation will cause natural resonance on the capacitor Cr and the inductor (L r +L lk1 +L m ) of the ideal transformer Tr, and then the primary side of the ideal transformer Tr will generate a response signal ir corresponding to the pulse current excitation.
  • the high frequency AC response signal ir circulates in the primary winding of the ideal transformer Tr. After passing through the detection circuit, a signal V ir reflecting the current magnitude and phase of the response signal ir can be obtained and sent to the second controller 120A.
  • the second controller 120A obtains the frequency of the signal V ir , that is, obtains the resonant frequency f 2 , and since the inductance value of the inductor Lr and the capacitance value of the capacitor Cr are known parameters, and the primary side is determined according to formula (1)
  • the leakage inductance L lk (and the leakage inductance L lk2 of the secondary side), therefore, the excitation inductance L m can be further determined according to equation (2).
  • the second controller 120A may perform AD sampling on the acquired signal V ir to obtain a digital signal, and then perform numerical analysis processing.
  • the second controller 120A may include an MCU, and the MCU performs AD sampling on the signal V ir and analysis and processing of the value.
  • the second controller 120A may further include an ADC (Analog to Digital Converter, analog-to-digital converter), the ADC performs AD sampling on the signal V ir , and transmits the obtained digital signal to the MCU for numerical analysis and processing.
  • ADC Analog to Digital Converter, analog-to-digital converter
  • the second controller 120A may also perform analog signal processing on the signal V ir first, that is, sampling the envelope signal of the signal V ir to obtain amplitude information; then obtain a square wave signal through a comparator, and then send it into the timer to get frequency information.
  • the detection circuit may perform signal processing on the collected signal to obtain a digital signal, and then transmit the digital signal to the second controller 120A.
  • the above process of sampling and calculating and analyzing the signal V ir may be based on a relatively mature technology in the field of signal processing, which will not be repeated in this embodiment of the present application.
  • the first controller 150A provided in this embodiment of the present application may be integrated with the motor controller 150 in FIG. 1 , for example, integrated on the same MCU, or may be independently set up, for example, integrated on different MCUs; the second control The controller 120A and the excitation controller 120 in FIG. 1 can be integrated together, for example, on the same MCU, or can be independently set up, for example, integrated on different MCUs, which are not specifically limited in the embodiments of the present application.
  • first controller 150A and the second controller 120A may also be integrated on the same MCU.
  • the detection circuit 170 specifically includes the current transformer CT as an example for illustration.
  • the detection circuit 170 may also have other implementations, for example, the primary voltage of the ideal transformer Tr may also be detected, but in general, the In order to detect the amplitude and frequency of the response signal corresponding to the pulse current excitation, to obtain the electrical parameters of the wireless excitation system.
  • the accurate primary leakage inductance L lk1 and excitation inductance L m can be obtained. If the currently detected detection values of L lk1 and L m When the absolute value of the difference with the preset electrical parameter is less than or equal to the preset threshold, it indicates that the radio excitation system is normal at this time, otherwise it is determined that there is a fault.
  • the preset threshold may be determined according to the actual situation, which is not specifically limited in this embodiment of the present application.
  • the wireless excitation system provided by the embodiments of the present application can complete the detection on the stator side of the motor without adding a complex hardware circuit on the rotor side of the motor, thus reducing cost and improving reliability.
  • the preset electrical parameters and preset thresholds may be predetermined and stored in the storage unit, and may be recalled when they are to be used.
  • the above embodiment describes the principle that the second controller uses electrical parameters to determine whether there is a fault in the wireless excitation system, and the principle that the second controller uses the received response signal to detect faults is specifically described below.
  • FIG. 5 is a schematic diagram of a pulse current excitation and a response signal provided by an embodiment of the present application.
  • the second controller 120A obtains the waveform characteristics of the signal V ir , including frequency and amplitude.
  • the frequency and amplitude of the signal V ir characterize the frequency and amplitude of the current response ir on the primary side of the excitation transformer, and can be used to replace ir for fault detection.
  • the second controller 120A determines that the rectifier bridge diode of the rotor has an open-circuit fault; when the frequency of Vir is higher than the preset frequency range, it determines that the rectifier bridge diode of the rotor has a short-circuit fault ; When the amplitude of V ir is higher than the preset amplitude range, it is determined that the capacitance value of the output capacitor of the rectifier bridge is abnormal.
  • the preset frequency range and the preset amplitude range can be pre-determined and stored in the storage unit, and recalled when they are to be used.
  • Embodiment 4 is a diagrammatic representation of Embodiment 4:
  • the embodiments of the present application further provide a detection method applied to the radio excitation system, which will be described in detail below with reference to the accompanying drawings.
  • FIG. 6 is a flowchart of a method for detecting a radio excitation system provided by an embodiment of the present application.
  • S601 Control the first power conversion circuit to inject current excitation into the stator winding of the electric excitation motor, so that current is generated on the excitation winding.
  • the load characteristic of the diode used in the rectifier bridge is related to the current direction, and by changing the injected current excitation, the load characteristic of the secondary side of the excitation transformer can be changed.
  • S602 Control the second power conversion circuit to inject pulse current into the primary side of the excitation transformer when the current generated on the excitation winding short-circuits the secondary side of the excitation transformer, and when the current generated on the excitation winding makes the secondary side of the excitation transformer open circuit Excitation, and use the response signal of the primary side of the excitation transformer to determine the electrical parameters of the excitation transformer.
  • the load characteristics of the secondary side of the excitation transformer are different, and different response signals are generated under the excitation of the pulse current. Therefore, the electrical parameters of the excitation transformer can be determined according to the received response signals to facilitate fault judgment.
  • this figure is a flowchart of another method for detecting a radio excitation system provided by an embodiment of the present application.
  • S701 Control the first power conversion circuit to inject a gradually decreasing d-axis current excitation into the stator winding of the electric excitation motor within a first preset time, so as to generate current on the excitation winding and short-circuit the secondary side of the excitation transformer.
  • S702 Control the second power conversion circuit to inject pulse current excitation into the primary side of the excitation transformer, and obtain the leakage inductance value of the primary side and the leakage inductance of the secondary side of the excitation transformer by using the resonance frequency of the response signal when the secondary side of the excitation transformer is short-circuited value.
  • the first preset time is greater than the duration of the pulse current excitation.
  • S703 Control the first power conversion circuit to inject gradually increasing d-axis current excitation into the stator winding of the electric excitation motor within the second preset time, so as to generate current on the excitation winding and short-circuit the secondary side of the excitation transformer.
  • S704 Control the second power conversion circuit to inject pulse current excitation into the primary side of the excitation transformer, and obtain the inductance value of the excitation inductance of the excitation transformer by using the resonance frequency of the response signal when the secondary side of the excitation transformer is disconnected.
  • the second preset time is greater than the duration of the pulse current excitation.
  • S705 Use the acquired electrical parameters to perform fault detection on the wireless excitation system.
  • S706 Use the acquired response signal to perform fault detection on the wireless excitation system.
  • the method provided by the embodiments of the present application requires lower hardware costs, and the detection can be completed on the stator side of the motor , so the method has higher reliability.
  • Embodiment 5 is a diagrammatic representation of Embodiment 5:
  • the embodiments of the present application also provide an electric vehicle applied to the radio excitation system, which will be described in detail below with reference to the accompanying drawings.
  • FIG. 7 this figure is a schematic diagram of an electric vehicle provided by an embodiment of the present application.
  • the electric vehicle 500 includes the radio excitation system 300 and the power battery pack 400 provided in the above embodiments.
  • the power battery pack 400 is used to supply power to the wireless excitation system 300 , which is equivalent to the DC power supply 110 in FIGS. 1-3 .
  • the wireless excitation system 300 includes an excitation transformer, a motor, a detection circuit, a second power conversion circuit, a first power conversion circuit, a first controller, and a second controller.
  • an excitation transformer for the specific implementation manner and working principle of the radio excitation system 300, reference may be made to the relevant descriptions in the above embodiments, and details are not described herein again in the embodiments of the present application.
  • the electric vehicle provided by the embodiment of the present application includes a radio excitation system, and the first controller of the radio excitation system controls the first power conversion circuit to inject current excitation into the windings of the stator of the motor, so that the excitation windings generate current, which in turn changes the load characteristics of the secondary side of the excitation transformer.
  • the second controller controls the second power conversion circuit to inject into the primary side of the excitation transformer when the current generated by the excitation winding short-circuits the secondary side of the excitation transformer, and when the current generated in the excitation winding makes the secondary side of the excitation transformer open circuit Pulse current excitation.
  • the pulse current excitation causes the primary side of the excitation transformer to generate a response signal corresponding to the pulse current excitation.
  • the detection circuit obtains the response signal of the primary side of the excitation transformer, and then transmits it to the second controller. Because the load characteristics of the secondary side of the excitation transformer are different, the obtained response signal is different, and the second controller can determine according to the received response signal.
  • the electrical parameters of the excitation transformer to facilitate fault diagnosis.
  • the wireless excitation system can complete the detection on the stator side of the motor without adding complex hardware circuits on the rotor side of the motor, thereby reducing cost and improving reliability.
  • the second controller may determine that the diode of the rectifier bridge has an open-circuit fault; when the frequency is higher than the normal frequency range, it may determine that the output of the rectifier bridge is short-circuited; When the amplitude of the signal is higher than the normal range, it can be determined that the output capacitance value of the rectifier bridge has dropped abnormally.
  • the second controller and the first controller in the above embodiments of the present application may be Application Specific Integrated Circuit (ASIC), Programmable Logic Device (PLD), Digital Signal Processor (Digital Signal Processor) , DSP) or a combination thereof.
  • the above-mentioned PLD can be a complex programmable logic device (Complex Programmable Logic Device, CPLD), a field-programmable gate array (Field-programmable Gate Array, FPGA), a general array logic (Generic Array Logic, GAL) or any combination thereof.
  • the application examples are not specifically limited.
  • At least one (item) refers to one or more, and "a plurality” refers to two or more.
  • “And/or” is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, “A and/or B” can mean: only A, only B, and both A and B exist , where A and B can be singular or plural.
  • the character “/” generally indicates that the associated objects are an “or” relationship.
  • At least one item(s) below” or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s).
  • At least one (a) of a, b or c can mean: a, b, c, "a and b", “a and c", “b and c", or "a and b and c" ", where a, b, c can be single or multiple.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)

Abstract

本申请公开了一种无线电励磁系统、检测方法及电动汽车，涉及电子电力技术领域。该系统的第一功率变换电路的输入端连接电源，输出端连接电励磁电机的定子绕组；第二功率变换电路的输入端连接电源，输出端连接励磁变压器原边；励磁变压器将电励磁电机的励磁绕组所需能量从定子传递至转子；第一控制器控制第一功率变换电路向定子绕组注入电流激励以使励磁绕组上产生电流；检测电路获取励磁变压器原边的响应信号并发送至第二控制器；第二控制器当励磁绕组上产生的电流使励磁变压器的副边短路以及断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励并利用响应信号确定励磁变压器的电参数。利用该系统能够检测无线电励磁系统的电参数。

Description

一种无线电励磁系统、检测方法及电动汽车
本申请要求于2020年7月31日提交中国国家知识产权局、申请号为202010760367.9、发明名称为“一种无线电励磁系统、检测方法及电动汽车”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及电子电力技术领域，尤其涉及一种无线电励磁系统、检测方法及电动汽车。
背景技术
当电动汽车的驱动电机为永磁同步电机时，电机以高转速运行时，电机定子绕组上会产生高压反电动势，此时如果进一步提高电机的转速，将可能造成第一控制器的损坏。因为电机转子的永磁材料产生的磁场不可调节，只能调节电机定子侧d轴(与电机转子的磁场方向一致)的电流来改变气隙磁场，从而降低电机定子绕组的反电动势，但当增加d轴电流时，会使得电机在高转速运行时的效率明显下降。
目前为了提高电机在高转速运行时的效率，可以采用无线电励磁同步电机(以下简称电励磁电机)，其中，无线电励磁即通过励磁变压器，采用无线方式给电机转子的励磁绕组供电，在电机转子上产生大小可控的磁场以代替电子转子的永磁材料的恒定磁场，以使电机转子磁场的大小得到控制。
但是因为励磁变压器的参数偏差和安装误差等因素的影响，导致实际的电参数可能发生变化，而当电励磁电机和励磁变压器完成组装后，难以再次检测电参数，不便进行故障判断。
发明内容
为了解决现有技术存在的上述技术问题，本申请提供了一种无线电励磁系统、检测方法及电动汽车，能够检测无线电励磁系统的电参数。
第一方面，本申请提供了一种无线电励磁系统，包括：励磁变压器、励磁整流电路、电励磁电机、检测电路、第一功率变换电路、第二功率变换电路、第一控制器和第二控制器。第一功率变换电路的输入端连接电源，第一功率变换电路的输出端连接电励磁电机的定子绕组；第二功率变换电路的输入端连接电源，第二功率变换电路的输出端连接励磁变压器的原边；励磁变压器用于将电励磁电机的励磁绕组所需能量从定子传递至转子；励磁整流电路用于将励磁变压器的副边接收到的交流电转换为直流电后传输至所述励磁绕组；第一控制器用于控制第一功率变换电路向定子绕组注入电流激励以使励磁绕组上产生电流；检测电路用于获取励磁变压器的原边的响应信号并发送至第二控制器；第二控制器当励磁绕组上产生的电流使励磁变压器的副边短路，以及当励磁绕组上产生的电流使励磁变压器的副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，并利用响应信号确定励磁变压器的电参数。
该系统通过向电励磁电机的定子的绕组注入不同的电流激励，以使励磁绕组上产生电流，励磁绕组的电流的方向会影响电机转子侧的整流桥的负载特性，进而使得励磁变压器的副边可以呈现短路和断路两种不同的负载状态。第二控制器通过检测电路检测励磁变压器的原边该脉冲电流激励对应的响应信号，进而根据该响应信号确定励磁变压器的电参数。
结合第一方面，在第一种可能的实现方式中，电参数包括漏感值和励磁电感的电感值，第二控制器利用励磁变压器的副边短路时的响应信号的谐振频率，获取励磁变压器的原边的漏感值和所述励磁变压器的副边的漏感值；利用励磁变压器的副边断路时的响应信号的谐振频率，获取所述励磁变压器的励磁电感的电感值。
即该第二控制器可以根据副边处于短路和断路两种不同的负载状态时原边不同的响应信号获取励磁变压器的原边的漏感值、副边的漏感值和励磁电感的电感值。在一些实施例中，一般励磁变压器的原边的漏感值大小等于副边的漏感值。
结合第一方面，在第二种可能的实现方式中，第二控制器还用于当电参数和预设电参数的差的绝对值大于预设阈值时，确定无线电励磁系统存在故障。
即该系统的第二控制器可以利用电参数确定无线电励磁系统是否存在故障。
结合第一方面，在第三种可能的实现方式中，第二控制器还用于利用响应信号对无线电励磁系统进行故障检测。
由于本申请系统中获取的响应信号是励磁变压器的副边处于不同负载特性时，原边对于脉冲电流激励产生的响应，因此也可以利用响应信号来检测无线电励磁系统是否存在故障。
结合第一方面，在第四种可能的实现方式中，第二控制器具体用于：当响应信号的频率低于预设频率范围时，确定励磁整流电路的二极管存在断路故障；当响应信号的频率高于预设频率范围时，确定励磁整流电路的二极管存在短路故障；当响应信号的幅值高于预设幅值范围时，确定励磁整流电路的输出电容的电容值异常。
结合第一方面，在第五种可能的实现方式中，第一控制器在第一预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐步减小的d轴电流激励，以使励磁变压器的副边短路，d轴与所述转子的磁场方向一致；在第二预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐步增大的d轴电流激励，以使励磁变压器的副边短路。
其中，第一预设时间大于所述脉冲电流激励的持续时间，以确保脉冲电流激励的持续时间内，励磁变压器的副边处于短路状态。第二预设时间大于脉冲电流激励的持续时间，以确保脉冲电流激励的持续时间内，励磁变压器的副边处于断路状态。
结合第一方面，在第六种可能的实现方式中，第一控制器还用于向电励磁电机的定子绕组注入电流激励后，向第二控制器发送控制指令，控制指令用于指示第二控制器控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励。即第一控制器通知第二控制器开始进行电参数的检测。
结合第一方面，在第七种可能的实现方式中，检测电路具体包括电流互感器和信号处理电路，电流互感器的原边绕组连接所述励磁变压器的原边，电流互感器的副边绕组连接信号处理电路。信号处理电路用于对电流互感器采集的信号进行处理以获取响应信号，并将响应信号并发送至第二控制器。
结合第一方面，在第八种可能的实现方式中，第一控制器和第二控制器集成于一个微控制单元MCU。
在另一些实施例中，第一控制器和第二控制器也可以分别集成于不同的微控制单元。 第二方面，本申请还提供了一种无线电励磁系统的检测方法，应用于以上的实现方式提供的无线电励磁系统，该方法包括：
控制第一功率变换电路向电励磁电机的定子绕组注入电流激励，以使励磁绕组上产生电流；
当励磁绕组上产生的电流使励磁变压器的副边短路时，以及当励磁绕组上产生的电流使励磁变压器的副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，并利用励磁变压器的原边的响应信号确定励磁变压器的电参数。
结合第二方面，在第一种可能的实现方式中，电参数包括漏感值和励磁电感的电感值，所述利用励磁变压器的原边的响应信号确定励磁变压器的电参数具体包括：
利用励磁变压器的副边短路时的响应信号的谐振频率，获取励磁变压器的原边的漏感值和励磁变压器的副边的漏感值；
利用励磁变压器的副边断路时的响应信号的谐振频率，获取励磁变压器的励磁电感的电感值。
结合第二方面，在第二种可能的实现方式中，该方法还包括：当电参数和预设电参数的差的绝对值大于预设阈值时，确定无线电励磁系统存在故障。
结合第二方面，在第三种可能的实现方式中，该方法还包括：利用响应信号对无线电励磁系统进行故障检测。
结合第二方面，在第四种可能的实现方式中，利用响应信号对无线电励磁系统进行故障检测，具体包括：
当响应信号的频率低于预设频率范围时，确定励磁整流电路的二极管存在断路故障；当响应信号的频率高于预设频率范围时，确定励磁整流电路的二极管存在短路故障；当响应信号的幅值高于预设幅值范围时，确定励磁整流电路的输出电容的电容值异常。
结合第二方面，在第五种可能的实现方式中，所述控制第一功率变换电路向电机的定子绕组注入电流激励，以使励磁绕组上产生电流，具体包括：
在第一预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐步减小的d轴电流激励，以使所述励磁绕组上产生电流且使所述励磁变压器的副边短路，d轴与所述转子的磁场方向一致；
在第二预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐步增大的d轴电流激励，以使励磁绕组上产生电流且使所述励磁变压器的副边短路；
第一预设时间和第二预设时间大于脉冲电流激励的持续时间。
第三方面，本申请还提供了一种电动汽车，电动汽车包括以上任意一种实现方式提供的无线电励磁系统，还包括动力电池组，动力电池组用于为无线电励磁系统供电。
本申请提供的技术方案至少具有以下优点：
本申请提供的无线电励磁系统的第一控制器控制第一功率变换电路向电励磁电机的定子的绕组注入电流激励，以使励磁绕组上产生电流，进而改变了励磁变压器的副边的负载特性。第二控制器当励磁绕组上产的电流使励磁变压器的副边短路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，以及当励磁绕组上产的电流使励磁变压器的 副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励。脉冲电流激励使得励磁变压器的原边产生对应于该脉冲电流激励的响应信号。检测电路获取励磁变压器的原边的响应信号，然后传输至第二控制器，因为励磁变压器的副边的负载特性不同，因此获取到的响应信号不同，第二控制器可以根据接收的响应信号确定励磁变压器的电参数，以便于进行故障判断。
附图说明
图1为无线电励磁系统的示意图；
图2为本申请实施例提供的一种无线电励磁系统的示意图；
图3为本申请实施例提供的另一种无线电励磁系统的示意图；
图4为本申请实施例提供的信号时序的示意图；
图5为本申请实施例提供的脉冲电流激励与响应信号的示意图；
图6为本申请实施例提供的一种无线电励磁系统的检测方法的流程图；
图7为本申请实施例提供的另一种无线电励磁系统的检测方法的流程图；
图8为本申请实施例提供的一种电动汽车的示意图。
具体实施方式
为了使本技术领域的人员更清楚地理解本申请方案，下面首先说明无线电励磁系统的工作原理。
参见图1，该图为无线电励磁系统的示意图。
该无线电励磁系统包括：直流电源110、励磁控制器120、DC-AC变换器121、补偿电路130、励磁变压器140、电机控制器150、功率电路151、电机定子的绕组160以及电机转子210等。
其中，直流电源110为励磁控制器120和电机控制器150提供直流电，在一些实施例中，直流电源110可以为车载动力电池组。
DC-AC变换器121在励磁控制器120的控制下，将从直流电源110获取的直流电转换为交流电后提供给励磁变压器140。
补偿网络130主要包括电感和电容，用于匹配功率变换电路所需的阻抗关系，在一些实施例中也可以没有补偿网络130。
励磁变压器140包括励磁变压器原边141和励磁变压器副边211，励磁变压器原边141在电励磁电机中与电机定子相对静止，励磁变压器副边211与电机转子210一起高速旋转。电机转子210所需的励磁能量由励磁变压器140从电机定子侧送到电机转子侧。
电机控制器150用于控制功率电路151产生频率和幅值可控的交流电，并提供给电机的定子绕组160。
电机控制器150与励磁控制器120可以集成在一起，例如集成在同一个MCU(Micro Control Unit，微处理单元)上，也可以分别独立设置在不同的MCU上。当相互独立设置时，两者之间存在信号交互，电机控制器150将其励磁电流需求发送给励磁控制器120。
电机的定子绕组160利用电机控制器150注入频率和幅值可控的交流电，产生旋转磁场，该旋转磁场带动电机转子210同步转动。
电机转子210至少包括励磁变压器副边211、励磁整流电路212和励磁绕组213。其中，励磁变压器副边211用于接收励磁变压器原边141传送的能量，励磁整流电路212将励磁变压器副边211接收到的交流电转换为直流电，励磁绕组213上流过的直流电产生直流磁场。
由于该励磁变压器140为一种旋转变压器，存在一定的参数偏差和安装误差，导致实际的电参数可能发生变化，而当电励磁电机和励磁变压器140完成组装后，难以使用传统的方法再次检测电参数，不便进行故障判断。
目前，可以在电机转子210侧设置辅助电源、检测电路以及通信电路，将电机转子侧的电压、电流等信息以无线通信的方式传送至电机的定子侧，从而实现对于励磁电流的检测。
但是以上的技术方案一方面实现起来较为复杂，并且成本较高，另一方面需要在处于高速旋转以及高温环境下的电机转子侧设置电路，导致该电路的可靠性较低。
为了解决以上问题，本申请实施例提供了一种无线电励磁系统、检测方法及电动汽车，通过向电励磁电机的定子的绕组注入不同的电流激励，以使励磁绕组上产生电流，励磁绕组的电流的方向会影响电机转子侧的整流桥的负载特性，进而使得励磁变压器的副边可以呈现短路和断路两种不同的负载状态。当励磁变压器的副边短路时，以及当励磁变压器的副边断路时，向励磁变压器的原边注入脉冲电流激励。通过检测电路检测励磁变压器的原边该脉冲电流激励对应的响应信号，进而根据该响应信号确定励磁变压器的电参数。
综上所述，利用该系统能够准确检测无线电励磁系统的电参数，并且由于只需要检测励磁变压器的原边的电信号，无需在电机转子侧增加复杂的辅助电源以及通信电路等，因此降低了成本并且提升了可靠性。
为了使本技术领域的人员更清楚地理解本申请方案，下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行描述。
本申请说明中的“第一”、“第二”等用词仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量
在本申请中，除非另有明确的规定和限定，术语“连接”应做广义理解，例如，“连接”可以是固定连接，也可以是可拆卸连接，或成一体；可以是直接连接，也可以通过中间媒介间接连接。
实施例一：
本申请实施例提供了一种无线电励磁系统，下面结合附图具体说明。
参见图2，该图为本申请实施例提供的一种无线电励磁系统的示意图。
本申请实施例提供的无线电励磁系统包括：第二控制器120A、励磁变压器140、励磁整流电路212、电励磁电机、第二功率变换电路121A、第一功率变换电路151A、第一控制器150A和检测电路170。
其中，电励磁电机包括电机定子和电机转子210。电机定子是电机静止不动的部分，主要包括铁芯(图中未示出)、定子绕组160和机座(图中未示出)。电机转子是电机中的旋转部件，用于将电能转换为机械能，至少包括了励磁变压器副边211、励磁整流电路212和励 磁绕组213。本申请实施例中以励磁整流电路212为全桥整流电路为例进行说明，该全桥整流电路的每个半桥臂包括一个二极管。
本申请实施例的励磁变压器140的原边与电励磁电机的定子相对静止，励磁变压器140的副边与电励磁电机的转子相对静止。励磁变压器140用于将电励磁电机的励磁绕组需要的能量从电机定子传递至电机转子。
第二功率变换电路121A的输入端连接电源110，第二功率变换电路121A的输出端连接励磁变压器的原边。在一些实施例中，第二功率变换电路121A用于将直流电转换为交流电，即可以为图1中的DC-AC变换器121。
第一功率变换电路151A的输入端连接电源110，第一功率变换电路151A的输出端连接电励磁电机的定子绕组160。在一些实施例中，第一功率变换电路151A用于将直流电转换为交流电，即可以为图1中的功率电路151。第一控制器150A用于控制第一功率变换电路151A向电机的定子绕组注入电流激励，以使励磁绕组213上产生电流。下面具体说明。为了方便说明，本申请的以下说明中以电流方向沿电路顺时针为正，逆时针为负。
继续参见图2，当第一控制器150A控制第一功率变换电路151A向电机的定子绕组注入逐步减小的电流激励然后保持电流激励不变时，使得励磁绕组213产生正向电流i f，该正向电流通过励磁整流电路212的二极管实现回流，因此V 0＝0，使得整流桥短时间的短路。而当第一控制器150A控制第一功率变换电路151A向电机的定子绕组注入均匀增大的激励电流时，会使得励磁绕组213产生负向电流(与图示i f的方向相反)，该负向电流使励磁绕组负载与励磁整流电路212的输出没有关系，因此造成了励磁整流电路212短时间的开路。
即励磁绕组上产生的电流会使得励磁变压器的副边呈现短路和断路两种状态，即改变励磁变压器的副边的负载特性。
第二控制器120A当励磁绕组213上产的电流使励磁变压器的副边211短路时，以及当励磁绕组213上产的电流使励磁变压器的副边211断路时，控制第二功率变换电路121A向励磁变压器的原边注入脉冲电流激励。
检测电路170用于获取励磁变压器的原边的响应信号并传输至第二控制器120A。而励磁变压器的副边的负载特性不同，会导致其原边产生不同的响应信号。
第二控制器120A根据检测到的响应信号以及电路中已知的器件参数可以确定出励磁变压器的电参数，例如可以确定出励磁变压器的漏感和励磁电感等，即实现了对励磁变压器的电参数的检测。
综上所述，本申请实施例提供的无线电励磁系统的第一控制器控制第一功率变换电路向电机的定子的绕组注入电流激励，以使励磁绕组上产生电流，进而改变了励磁变压器的副边的负载特性。第二控制器当励磁绕组上产的电流使励磁变压器的副边短路时，以及当励磁绕组上产的电流使励磁变压器的副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励。脉冲电流激励使得励磁变压器的原边产生对应于该脉冲电流激励的响应信号。检测电路获取励磁变压器的原边的响应信号，然后传输至第二控制器，因为励磁变压器的副边的负载特性不同，因此获取到的响应信号不同，第二控制器可以根据接收的响应信号确定励磁变压器的电参数。
相较于在电机转子侧设置辅助电源、检测电路以及通信电路以实现电参数检测的方案而言，本申请实施例提供的无线电励磁系统的硬件成本更低，并且可以在电励磁电机的定子侧完成检测，无需在电励磁电机的转子侧增加硬件电路，因此提升了可靠性。
实施例二：
为了使本领域技术人员更清楚的理解本申请的技术方案，下面具体说明该无线电励磁系统的检测原理。
参见图3，该图为本申请实施例提供的另一种无线电励磁系统的示意图。
其中，补偿网络130包括电感Lr和电容Cr。电感Lr的电感值和电容Cr的电容值为系统设计时的已知参数。以第二功率变换电路121A为DC-AC变换器121为例进行说明。
图3中对励磁变压器140进行了等效处理，其等效模型包括：原边的漏感L lk1、副边的漏感L lk2、励磁电感为L m以及理想变压器T r。
本申请实施例以采用的检测电路170包括电流互感器CT和信号处理电路为例进行说明。其中，电流互感器CT用于检测励磁变压器原边的电流响应i r，获取的电信号为V ir；信号处理电路用于对电流互感器采集的信号进行处理以获取响应信号，并将所述响应信号并发送至所述第二控制器。
为了方便说明，以下说明中继续以电流方向沿电路顺时针为正，逆时针为负。
参见图4，该图为本申请实施例提供的信号时序的示意图。
以i d表示第一控制器150A控制第一功率变换电路151A向电机的定子绕组160注入的d轴电流激励，d轴与转子的磁场方向一致。当i d随时间逐渐减小时，在一些实施例中，可以采取满足
Figure PCTCN2021109959-appb-000001
为负值且保持不变，i d注入定子绕组160然后保持不变，使得激励绕组213产生正向电流i f，对应于图4中t1-t2时间段(第一预设时间)。此时正向的电流i f通过励磁整流电路212的二极管回流，励磁整流电路212的二极管正向导通，因此V0＝0，励磁整流电路212在这段时间内处于短路状态。
理想变压器Tr的副边(也即励磁变压器140的副边)短路时，理想变压器Tr等效为副边的漏感L lk2先与励磁电感为L m并联，在于原边的漏感L lk1串联。并且由于励磁电感L m的电感值远大于副边的漏感L lk2的电感值，因此两者并联后的电感值约为副边的漏感L lk2的电感值。从而励磁变压器140接入的电感量等效为(L lk1+L lk2)，此时理想变压器Tr的原边的谐振频率f 1为：
Figure PCTCN2021109959-appb-000002
在理想变压器Tr的副边短路期间，第二控制器120A向理想变压器Tr的原边注入脉冲电流激励。在一些实施例中，第二控制器120A通过控制DC-AC变换器121的工作状态向理想变压器Tr的原边注入脉冲电流激励。该脉冲电流激励在DC-AC变换器121的输出端产生相应的电压V AB。脉冲电流激励的持续时间短于理想变压器Tr的副边短路时间，本申请实施例对脉冲电流激励的持续时间不作具体限定。
例如可以持续5μs，t1-t2时间段可以相对较长，例如为脉冲电流激励的持续时间的20倍，以确保脉冲电流激励的持续时间内，理想变压器Tr的副边处于短路状态。
在一些实施例中，当第一控制器150A向电机的定子绕组160注入的电流激励后，第 一控制器150A可以向第二控制器120A发送检测指令，以通知第二控制器120A向理想变压器Tr的原边注入脉冲电流激励。
该脉冲电流激励会使得理想变压器Tr的电容Cr和电感(L r+L lk1+L lk2)上产生自然谐振，进而理想变压器Tr的原边产生脉冲电流激励对应的响应信号i r，响应信号i r的波形体现为衰减振荡的波形。
理想变压器Tr的原边绕组里流通的是高频交流的响应信号i r，通过检测电路170后，能够得到反映响应信号i r的电流大小和相位的信号V ir并发送至第二控制器120A。
第二控制器120A获取信号V ir的频率，即获取了谐振频率f 1，而由于电感Lr的电感值和电容Cr的电容值为已知参数，变压器模型中的原边的漏感L lk1和副边的漏感L lk2相同，因此可以根据式(1)确定出原边的漏感L lk1和副边的漏感L lk2。
然后第一控制器150A控制第一功率变换电路151A改变向电励磁电机的定子绕组注入的d轴电流激励i d，使得i d随时间逐步增大，在一些实施例中，可以采取
Figure PCTCN2021109959-appb-000003
为正值且保持不变，对应于图4中t3-t4(第二预设时间)时间段。此时励磁绕组213产生负向的电流i f(与图3所示的i f方向相反)，励磁整流电路212的二极管反向截止，励磁整流电路212在这段时间内处于断路(即开路)状态。
理想变压器Tr的副边(也即励磁变压器140的副边)断路时，理想变压器Tr等效为原边的漏感L lk1与励磁电感L m串联。从而励磁变压器140接入的电感量等效为(L lk1+L m)，此时理想变压器Tr的原边的谐振频率f 2为：
Figure PCTCN2021109959-appb-000004
在理想变压器Tr的副边开路期间，第二控制器120A向理想变压器Tr的原边注入脉冲电流激励。在一些实施例中，第二控制器120A通过控制DC-AC变换器121的工作状态向理想变压器Tr的原边注入脉冲电流激励。该脉冲电流激励在DC-AC变换器121的输出端产生相应的电压V AB。脉冲电流激励的持续时间短于理想变压器Tr的副边开路时间，本申请实施例对脉冲电流激励的持续时间不作具体限定。
例如可以持续5μs，t3-t4时间段可以相对较长，例如为脉冲电流激励的持续时间的20倍，以确保脉冲电流激励的持续时间内，理想变压器Tr的副边处于断路状态。
第二控制器120A在理想变压器Tr的副边开路期间注入的脉冲电流激励，与在理想变压器Tr的副边短路期间注入的脉冲电流激励可以相同，也可以不同，本申请实施例不作具体限定。
该脉冲电流激励会使得理想变压器Tr的电容Cr和电感(L r+L lk1+L m)上产生自然谐振，进而理想变压器Tr的原边产生脉冲电流激励对应的响应信号i r。
理想变压器Tr的原边绕组里流通的是高频交流的响应信号i r，通过检测电路后能够得到反映响应信号i r的电流大小和相位的信号V ir并发送至第二控制器120A。
第二控制器120A获取信号V ir的频率，即获取了谐振频率f 2，而由于电感Lr的电感值和电容Cr的电容值为已知参数，并且根据式(1)确定出了原边的漏感L lk(以及副边的漏感L lk2)，因此可以根据式(2)进一步确定出励磁电感L m。
在一些实施例中，第二控制器120A可以对获取的信号V ir进行AD采样后得到数字信 号，再进行数值的分析处理。第二控制器120A可以包括MCU，通过MCU对信号V ir进行AD采样以及数值的分析处理。第二控制器120A还可以包括ADC(Analog to Digital Converter，模拟数字转换器)，由ADC对信号V ir进行AD采样，将得到的数字信号传送至MCU进行数值的分析处理。
在另一些实施例中，第二控制器120A也可以先对信号V ir进行模拟信号处理，即对信号V ir的包络信号采样得到幅值信息；然后通过比较器得到方波信号，再送入计时器以得到频率信息。
在又一些实施例中，可以由检测电路对采集的信号进行信号处理，得到数字信号，再将数字信号传输至第二控制器120A。
以上对于信号V ir进行采样与计算分析的过程可以基于信号处理领域较为成熟的技术，本申请实施例在此不再赘述。
本申请实施例提供的第一控制器150A可以与图1中的电机控制器150集成在一起，例如集成在同一MCU上，也可以分别独立设置，例如分别集成在不同的MCU上；第二控制器120A与图1中的励磁控制器120可以集成在一起，例如集成在同一MCU上，也可以分别独立设置，例如分别集成在不同的MCU上，本申请实施例不作具体限定。
在另一些实施例中，第一控制器150A与第二控制器120A也可以集成在同一MCU上。
以上说明中以检测电路170具体包括电流互感器CT为例进行说明，检测电路170还可以有其它的实现方式，例如还可以对理想变压器Tr的原边电压进行检测，但总体来说，均是为了检测脉冲电流激励对应的响应信号的幅值和频率，以获取无线电励磁系统的电参数。
综上，通过对励磁变压器在副边短路和副边断路时的参数检测，能够获取准确的原边的漏感L lk1和励磁电感L m，如果当前检测得到的L lk1和L m的检测值与预设电参数的差的绝对值小于或等于预设阈值时，则表征此时无线电励磁系统正常，否则判定为出现故障。其中，预设阈值可以根据实际情况确定，本申请实施例对此不作具体限定。本申请实施例提供的无线电励磁系统可以在电机的定子侧完成检测，无需在电机的转子侧增加复杂的硬件电路，因此降低了成本并且提升了可靠性。
在一些实施例中，预设电参数和预设阈值可以预先确定并保存在存储单元中，待使用时进行调用。
实施例三
以上实施例中说明了第二控制器利用电参数判断无线励磁系统是否存在故障的原理，下面具体说明第二控制器利用接收到的响应信号进行故障检测的原理。
参见图5，该图为本申请实施例提供的脉冲电流激励与响应信号的示意图。
一并参见图3，通过第二控制120A向励磁变压器的原边电路注入脉冲电流激励后，该脉冲电流激励对应的电压V AB的波形如图5所示。
第二控制器120A获取信号V ir的波形特性，包括频率和幅值。信号V ir的频率和幅值表征励磁变压器的原边的电流响应i r的频率和幅值，可以以V ir代替i r进行故障检测。
第二控制器120A当V ir的频率低于预设频率范围时，确定转子的整流桥二极管存在断 路故障；当V ir的频率高于预设频率范围时，确定转子的整流桥二极管存在短路故障；当V ir的幅值高于预设幅值范围时，确定整流桥的输出电容的电容值异常。
其中，预设频率范围和预设幅值范围可以预先确定并保存在存储单元中，待使用时进行调用。
实施例四：
基于上述实施例提供的无线电励磁系统，本申请实施例还提供了一种应用于该无线电励磁系统的检测方法，下面结合附图具体说明。
参见图6，该图为本申请实施例提供的一种无线电励磁系统的检测方法的流程图。
本申请实施例提供的方法包括以下步骤：
S601:控制第一功率变换电路向电励磁电机的定子绕组注入电流激励，以使励磁绕组上产生电流。
当向电机的定子绕组注入电流激励时，会使电机的励磁绕组上产生电流，改变激励电流的波形特性，可以改变励磁绕组上产生电流的方向。而整流桥采用的二极管的负载特性与电流方向有关，进而通过改变注入的电流激励，能够改变励磁变压器的副边的负载特性。
S602：当励磁绕组上产的电流使励磁变压器的副边短路时，以及当励磁绕组上产的电流使励磁变压器的副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，并利用励磁变压器的原边的响应信号确定励磁变压器的电参数。
励磁变压器的副边的负载特性不同，在脉冲电流激励下回产生不同的响应信号，因此可以根据接收的响应信号确定励磁变压器的电参数，以便于进行故障判断。
继续参见图3，下面结合无线电励磁系统的具体实现方式进行说明。
一并参见图7，该图为本申请实施例提供的另一种无线电励磁系统的检测方法的流程图。
具体包括以下步骤：
S701：在第一预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐渐减小的d轴电流激励，以使励磁绕组上产生电流且使励磁变压器的副边短路。
S702：控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，利用励磁变压器的副边短路时的响应信号的谐振频率，获取励磁变压器的原边的漏感值和副边的漏感值。
第一预设时间大于脉冲电流激励的持续时间。
S703：在第二预设时间内控制第一功率变换电路向电励磁电机的定子绕组注入逐渐增大的d轴电流激励，以使励磁绕组上产生电流且使励磁变压器的副边短路。
S704：控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励，利用励磁变压器的副边断路时的响应信号的谐振频率，获取励磁变压器的励磁电感的电感值。
第二预设时间大于脉冲电流激励的持续时间。
S705：利用获取的电参数对无线电励磁系统进行故障检测。
当励磁变压器的原边的漏感值和副边的漏感值，以及励磁电感的电感值和预设电参数的差的绝对值大于预设阈值时，确定无线电励磁系统存在故障。
S706：利用获取的响应信号对无线电励磁系统进行故障检测。
当响应信号的频率低于预设频率范围时，确定转子的整流桥二极管存在断路故障；
当响应信号的频率高于预设频率范围时，确定转子的整流桥二极管存在短路故障；
当响应信号的幅值高于预设幅值范围时，确定整流桥的输出电容的电容值异常。
本申请实施例提供的以上步骤仅是为了方便说明，并不构成对于本申请的限定。本领域技术人员可以根据实际情况调整或修改以上的步骤，例如可以将S705和S706的顺序进行调换。
综上所述，利用本申请实施例提供的方法，通过向电机的定子的绕组注入不同的电流激励，以使励磁绕组上产生方向不同的电流，进而改变了励磁变压器的副边的负载特性。当励磁绕组上产的电流使励磁变压器的副边短路时，以及当励磁绕组上产的电流使励磁变压器的副边断路时，向励磁变压器的原边注入脉冲电流激励。脉冲电流激励使得励磁变压器的原边产生对应于该脉冲电流激励的响应信号。因为励磁变压器的副边的负载特性不同，因此检测到的响应信号不同，然后根据检测到的响应信号确定励磁变压器的电参数，进而还可以进行故障分析。
相较于在电机转子侧设置辅助电源、检测电路以及通信电路以实现电参数检测的方案而言，本申请实施例提供的方法所需的硬件成本更低，并且可以在电机的定子侧完成检测，因此该方法具有更高的可靠性。
实施例五：
基于以上实施例提供的无线电励磁系统，本申请实施例还提供了一种应用于该无线电励磁系统的电动汽车，下面结合附图具体说明。
参见图7，该图为本申请实施例提供的一种电动汽车的示意图。
该电动汽车500包括以上实施例提供的无线电励磁系统300以及动力电池组400。
其中，动力电池组400用于为无线电励磁系统300供电，即相当于附图1-3中的直流电源110。
无线电励磁系统300包括励磁变压器、电机、检测电路、第二功率变换电路、第一功率变换电路、第一控制器和第二控制器。关于无线电励磁系统300的具体实现方式和工作原理可以参见以上实施例中的相关说明，本申请实施例在此不再赘述。
综上所述，本申请实施例提供的电动汽车包括了无线电励磁系统，该无线电励磁系统的第一控制器控制第一功率变换电路向电机的定子的绕组注入电流激励，以使励磁绕组上产生电流，进而改变了励磁变压器的副边的负载特性。第二控制器当励磁绕组上产的电流使励磁变压器的副边短路时，以及当励磁绕组上产的电流使励磁变压器的副边断路时，控制第二功率变换电路向励磁变压器的原边注入脉冲电流激励。脉冲电流激励使得励磁变压器的原边产生对应于该脉冲电流激励的响应信号。检测电路获取励磁变压器的原边的响应信号，然后传输至第二控制器，因为励磁变压器的副边的负载特性不同，因此获取到的响应信号不同，第二控制器可以根据接收的响应信号确定励磁变压器的电参数，以便于进行故障判断。该无线电励磁系统可以在电机的定子侧完成检测，无需在电机的转子侧增加复杂的硬件电路，因此降低了成本并且提升了可靠性。
在一些实施例中，第二控制器当响应信号的频率低于正常频率范围时，可以确定整流 桥的二极管存在开路故障；当频率高于正常频率范围时，可以确定整流桥输出短路；当响应信号的幅值高于正常范围时，可以确定整流桥输出电容值下降异常。
本申请以上实施例中的第二控制器和第一控制器可以为专用集成电路(Application Specific Integrated Circuit，ASIC)、可编程逻辑器件(Programmable Logic Device，PLD)、数字信号处理器(Digital Signal Processor，DSP)或其组合。上述PLD可以是复杂可编程逻辑器件(Complex Programmable Logic Device，CPLD)、现场可编程逻辑门阵列(Field-programmable Gate Array，FPGA)、通用阵列逻辑(Generic Array Logic,GAL)或其任意组合，本申请实施例不作具体限定。
可以理解的是，本申请提供的技术方案还可以应用在无线励磁发电机中，利用类似的检测电路和控制方法进行电参数的检测以及故障的判断。
应当理解，在本申请中，“至少一个(项)”是指一个或者多个，“多个”是指两个或两个以上。“和/或”，用于描述关联对象的关联关系，表示可以存在三种关系，例如，“A和/或B”可以表示：只存在A，只存在B以及同时存在A和B三种情况，其中A，B可以是单数或者复数。字符“/”一般表示前后关联对象是一种“或”的关系。“以下至少一项(个)”或其类似表达，是指这些项中的任意组合，包括单项(个)或复数项(个)的任意组合。例如，a，b或c中的至少一项(个)，可以表示：a，b，c，“a和b”，“a和c”，“b和c”，或“a和b和c”，其中a，b，c可以是单个，也可以是多个。
本说明书中的各个实施例均采用递进的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。以上所描述的装置实施例仅仅是示意性的，其中所述作为分离部件说明的单元及模块可以是或者也可以不是物理上分开的。另外，还可以根据实际的需要选择其中的部分或者全部单元和模块来实现本实施例方案的目的。本领域普通技术人员在不付出创造性劳动的情况下，即可以理解并实施。
以上所述仅是本申请的具体实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本申请原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也应视为本申请的保护范围。

Claims (16)

  1. 一种无线电励磁系统，其特征在于，包括：励磁变压器、励磁整流电路、电励磁电机、检测电路、第一功率变换电路、第二功率变换电路、第一控制器和第二控制器；
    所述第一功率变换电路的输入端连接所述电源，所述第一功率变换电路的输出端连接所述电励磁电机的定子绕组；所述第二功率变换电路的输入端连接电源，所述第二功率变换电路的输出端连接所述励磁变压器的原边；
    所述励磁变压器用于将所述电励磁电机的励磁绕组所需能量从定子传递至转子；所述励磁整流电路用于将所述励磁变压器的副边接收到的交流电转换为直流电后传输至所述励磁绕组；
    所述第一控制器用于控制所述第一功率变换电路向所述定子绕组注入电流激励以使所述励磁绕组上产生电流；
    所述检测电路用于获取所述励磁变压器的原边的响应信号并发送至所述第二控制器；
    所述第二控制器，用于当所述励磁绕组上产生的电流使所述励磁变压器的副边短路，以及当所述励磁绕组上产生的电流使所述励磁变压器的副边断路时，控制所述第二功率变换电路向所述励磁变压器的原边注入脉冲电流激励，并利用所述响应信号确定所述励磁变压器的电参数。
  2. 根据权利要求1所述的系统，其特征在于，所述电参数包括漏感值和励磁电感的电感值，所述第二控制器具体用于：
    利用所述励磁变压器的副边短路时的响应信号的谐振频率，获取所述励磁变压器的原边的漏感值和所述励磁变压器的副边的漏感值；
    利用所述励磁变压器的副边断路时的响应信号的谐振频率，获取所述励磁变压器的励磁电感的电感值。
  3. 根据权利要求1所述的系统，其特征在于，所述第二控制器还用于当所述电参数和预设电参数的差的绝对值大于预设阈值时，确定所述无线电励磁系统存在故障。
  4. 根据权利要求1所述的系统，其特征在于，所述第二控制器还用于利用所述响应信号对所述无线电励磁系统进行故障检测。
  5. 根据权利要求4所述的系统，其特征在于，所述第二控制器，具体用于：
    当所述响应信号的频率低于预设频率范围时，确定所述励磁整流电路的二极管存在断路故障；
    当所述响应信号的频率高于所述预设频率范围时，确定所述励磁整流电路的二极管存在短路故障；
    当所述响应信号的幅值高于预设幅值范围时，确定所述励磁整流电路的输出电容的电容值异常。
  6. 根据权利要求1所述的系统，其特征在于，所述第一控制器具体用于：
    在第一预设时间内控制所述第一功率变换电路向所述电励磁电机的定子绕组注入逐步减小的d轴电流激励，以使所述励磁变压器的副边短路，所述d轴与所述转子的磁场方向一致；
    在第二预设时间内控制所述第一功率变换电路向所述电励磁电机的定子绕组注入逐步增大的d轴电流激励，以使所述励磁变压器的副边短路；
    所述第一预设时间和第二预设时间大于所述脉冲电流激励的持续时间。
  7. 根据权利要求1-6所述的系统，其特征在于，所述第一控制器，还用于：
    向所述电励磁电机的定子绕组注入电流激励后，向所述第二控制器发送控制指令，所述控制指令用于指示所述第二控制器控制所述第二功率变换电路向所述励磁变压器的原边注入所述脉冲电流激励。
  8. 根据权利要求1-6中任意一项所述的系统，其特征在于，所述检测电路具体包括电流互感器和信号处理电路，所述电流互感器的原边绕组连接所述励磁变压器的原边，所述电流互感器的副边绕组连接所述信号处理电路；
    所述信号处理电路，用于对所述电流互感器采集的信号进行处理以获取所述响应信号，并将所述响应信号并发送至所述第二控制器。
  9. 根据权利要求1-6中任意一项所述的系统，其特征在于，所述第一控制器和所述第二控制器集成于一个微控制单元MCU。
  10. 一种无线电励磁系统的检测方法，其特征在于，所述系统包括励磁变压器、励磁整流电路、电励磁电机、第一功率变换电路和第二功率变换电路，所述第一功率变换电路的输入端连接电源，所述第一功率变换电路的输出端连接所述电励磁电机的定子绕组，所述第二功率变换电路的输入端连接电源，所述第二功率变换电路的输出端连接所述励磁变压器的原边，所述励磁变压器用于将所述电励磁电机的励磁绕组所需能量从定子传递至转子，所述励磁整流电路用于将所述励磁变压器的副边接收到的交流电转换为直流电后传输至所述励磁绕组；所述方法包括：
    控制所述第一功率变换电路向所述电励磁电机的定子绕组注入电流激励，以使所述励磁绕组上产生电流；
    当所述励磁绕组上产生的电流使所述励磁变压器的副边短路时，以及当所述励磁绕组上产生的电流使所述励磁变压器的副边断路时，控制所述第二功率变换电路向所述励磁变压器的原边注入脉冲电流激励，并利用所述励磁变压器的原边的响应信号确定所述励磁变压器的电参数。
  11. 根据权利要求10所述的方法，其特征在于，所述电参数包括漏感值和励磁电感的电感值，所述利用所述励磁变压器的原边的响应信号确定所述励磁变压器的电参数具体包括：
    利用所述励磁变压器的副边短路时的响应信号的谐振频率，获取所述励磁变压器的原边的漏感值和所述励磁变压器的副边的漏感值；
    利用所述励磁变压器的副边断路时的响应信号的谐振频率，获取所述励磁变压器的励磁电感的电感值。
  12. 根据权利要求10所述的方法，其特征在于，所述方法还包括：
    当所述电参数和预设电参数的差的绝对值大于预设阈值时，确定所述无线电励磁系统存在故障。
  13. 根据权利要求10所述的方法，其特征在于，所述方法还包括：
    利用所述响应信号对所述无线电励磁系统进行故障检测。
  14. 根据权利要求13所述的方法，其特征在于，所述利用所述响应信号对所述无线电励磁系统进行故障检测，具体包括：
    当所述响应信号的频率低于预设频率范围时，确定所述励磁整流电路的二极管存在断路故障；
    当所述响应信号的频率高于所述预设频率范围时，确定所述励磁整流电路的二极管存在短路故障；
    当所述响应信号的幅值高于预设幅值范围时，确定所述励磁整流电路的输出电容的电容值异常。
  15. 根据权利要求10所述的方法，其特征在于，所述控制所述第一功率变换电路向所述电机的定子绕组注入电流激励，以使所述励磁绕组上产生电流，具体包括：
    在第一预设时间内控制所述第一功率变换电路向所述电励磁电机的定子绕组注入逐步减小的d轴电流激励，以使所述励磁绕组上产生电流且使所述励磁变压器的副边短路，所述d轴与所述转子的磁场方向一致；
    在第二预设时间内控制所述第一功率变换电路向所述电励磁电机的定子绕组注入逐步增大的d轴电流激励，以使所述励磁绕组上产生电流且使所述励磁变压器的副边短路；
    所述第一预设时间和第二预设时间大于所述脉冲电流激励的持续时间。
  16. 一种电动汽车，其特征在于，所述电动汽车包括权利要求1-9中任意一项所述的无线电励磁系统，还包括动力电池组，所述动力电池组用于为所述无线电励磁系统供电。
PCT/CN2021/109959 2020-07-31 2021-08-02 一种无线电励磁系统、检测方法及电动汽车 WO2022022733A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP21851108.7A EP4181389A4 (en) 2020-07-31 2021-08-02 RADIO EXCITATION SYSTEM, DETECTION METHOD AND ELECTRIC VEHICLE

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010760367.9A CN114094897A (zh) 2020-07-31 2020-07-31 一种无线电励磁系统、检测方法及电动汽车
CN202010760367.9 2020-07-31

Publications (1)

Publication Number Publication Date
WO2022022733A1 true WO2022022733A1 (zh) 2022-02-03

Family

ID=80037686

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/109959 WO2022022733A1 (zh) 2020-07-31 2021-08-02 一种无线电励磁系统、检测方法及电动汽车

Country Status (3)

Country Link
EP (1) EP4181389A4 (zh)
CN (1) CN114094897A (zh)
WO (1) WO2022022733A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010077603A (ja) * 2008-09-24 2010-04-08 Denso Corp 車両制御システム及びそれに用いる腕時計型無線携帯キー
CN107104613A (zh) * 2017-06-29 2017-08-29 同济大学 一种同步电机转子励磁方法及装置
CN107222006A (zh) * 2017-08-03 2017-09-29 北京理工大学 一种无线充电系统输出能量控制电路及控制方法
CN107707171A (zh) * 2017-09-26 2018-02-16 华中科技大学 一种电励磁电机励磁装置及其参数获取方法

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2707335A1 (en) * 2007-09-11 2009-03-19 Abb Schweiz Ag Method and apparatus for determining a field current in brushless electrical machines
CN202585078U (zh) * 2012-05-25 2012-12-05 深圳市中兴昆腾有限公司 Llc变压器
CN103281024B (zh) * 2013-04-22 2016-06-08 广东电网公司电力科学研究院 一种基于全控器件的交流励磁系统
GB201400701D0 (en) * 2014-01-16 2014-03-05 Rolls Royce Plc Fault detection in brushless exciters
DE102014209607A1 (de) * 2014-05-21 2015-11-26 Bayerische Motoren Werke Aktiengesellschaft Rotor für eine Synchronmaschine
CN104038124B (zh) * 2014-06-06 2017-07-07 国电南瑞科技股份有限公司 基于双励磁绕组的励磁控制系统
CN111141956B (zh) * 2019-12-31 2022-03-11 国网山东省电力公司淄博供电公司 一种基于微积分方程组单相变压器短路参数在线监测方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010077603A (ja) * 2008-09-24 2010-04-08 Denso Corp 車両制御システム及びそれに用いる腕時計型無線携帯キー
CN107104613A (zh) * 2017-06-29 2017-08-29 同济大学 一种同步电机转子励磁方法及装置
CN107222006A (zh) * 2017-08-03 2017-09-29 北京理工大学 一种无线充电系统输出能量控制电路及控制方法
CN107707171A (zh) * 2017-09-26 2018-02-16 华中科技大学 一种电励磁电机励磁装置及其参数获取方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4181389A4

Also Published As

Publication number Publication date
EP4181389A1 (en) 2023-05-17
EP4181389A4 (en) 2023-12-20
CN114094897A (zh) 2022-02-25

Similar Documents

Publication Publication Date Title
CN106357164B (zh) 一种双凸极高压直流起动发电系统及控制方法
US20220194239A1 (en) System and method for charging electric vehicles
CN110333427B (zh) 柔性直流输电系统送端换流器igbt开路故障诊断方法
CN106849702A (zh) 一种带有故障监测功能的新型旋转整流器
CN109713958A (zh) 三级式无刷起动/发电机三相交流励磁系统及控制方法
CN110138196B (zh) 一种多支路储能变流器直流软启动控制方法及系统
CN112532128A (zh) 一种航空大功率复合无刷起动发电系统及其控制方法
CN102208870B (zh) 侦测磁性装置的连续电流模式运作的方法及装置
CN105391356A (zh) 无刷双馈电机启动控制系统和方法
US20230147551A1 (en) Electric drive system, powertrain, and electric vehicle
US20230163705A1 (en) Wireless excitation system, detection method, and electric vehicle
JP6526800B2 (ja) Ｄｃ−ｄｃ直列共振コンバータを有したバッテリ充電器を制御する方法
Kang et al. A primary-side control method of wireless power transfer for motor electric excitation
WO2013004110A1 (zh) 太阳能光伏并网交错并联反激逆变器
WO2022022733A1 (zh) 一种无线电励磁系统、检测方法及电动汽车
CN107947672A (zh) 一种宽转速范围开关磁阻电机系统效率优化控制方法
CN112421792B (zh) 一种无线充电系统及恒流/恒压充电优化的控制方法
CN114079404A (zh) 并列结构双凸极高压直流起动发电系统及其起动控制方法
CN101860210A (zh) 一种新型的升压斩波电路级联结构
CN102545754A (zh) 一种绕组开路式永磁双凸极起动发电系统
CN102223085A (zh) 混合励磁发电机和直流变换器组合的航空发动机专用电源系统
CN105696250A (zh) 一种洗衣机的节能控制方法及洗衣机
CN205900500U (zh) X射线管旋转阳极驱动装置
Xie et al. A novel high power density dual-buck inverter with coupled filter inductors
CN205092637U (zh) 一种高效高功率电动汽车无线充电装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21851108

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2021851108

Country of ref document: EP

Effective date: 20230209

NENP Non-entry into the national phase

Ref country code: DE