Electric machine with integrated point field detector and system for multi-parameter sensing

Abstract

The present invention relates to electric machines with integrated point field detectors and systems for multi-parameter sensing. An electric machine disposed within a housing includes a stator, a rotor, and one or more point field detectors. The stator receives electrical current from an inverter. The rotor is connected to a shaft and causes the shaft to rotate based on a magnetic field generated by the stator. The one or more point field detectors are configured to detect leakage flux within the housing. The stator, the rotor, and the one or more point field detectors are disposed within the housing.

Description

Technical Field

[0001] The information provided in this section is for the purpose of presenting the general background of this disclosure. To the extent described in this section, neither the work of the currently named inventors, nor any aspect of this specification that may otherwise not qualify as prior art at the time of filing, is expressly or implicitly acknowledged as contradicting the prior art of this disclosure.

[0002] This disclosure relates to a system for detecting the status of an electric motor in the propulsion system of a vehicle. Background Technology

[0003] The vehicle's propulsion system may include one or more electric motors. Each electric motor may be used to drive one or more axles and / or one or more wheels of the vehicle. As an example, an electric motor may be used to drive the vehicle's axles via a differential. Based on a torque request, a controller may signal the electric motor to rotate the input gear of the differential, and thus, to rotate the wheel attached to the axle. The controller may adjust the current, voltage, and / or power level of the electric motor to control the vehicle's acceleration, deceleration, and / or speed. Summary of the Invention

[0004] An electric motor is provided, comprising a stator, a rotor, and one or more field detectors disposed within a housing. The stator receives current from an inverter. The rotor is connected to a shaft and rotates the shaft based on a magnetic field generated by the stator. The one or more field detectors are configured to detect leakage flux within the housing. The stator, the rotor, and the one or more field detectors are disposed within the housing.

[0005] Among other features, one or more point field detectors are mounted on the rotor.

[0006] Among other features, the one or more point field detectors are mounted on the stator.

[0007] Among other features, the one or more point field detectors are disposed radially outside the stator and radially inside the housing.

[0008] Among other features, the one or more point field detectors are disposed on the radial outer surface of the stator.

[0009] Among other features, the one or more point field detectors are disposed on the radial inner surface of the housing.

[0010] Among other features, the one or more point field detectors are embedded in a dielectric material. The dielectric material is disposed between the stator and the housing.

[0011] Among other features, the one or more point field detectors comprise semiconductor chip-level devices.

[0012] Among other features, the one or more point field detectors include Hall effect sensors that are electrically isolated.

[0013] Among other features, the one or more point field detectors include magnetoresistive sensors that are isolated by current.

[0014] Among other features, a propulsion system is provided, which includes the motor and a first control module. The first control module is configured to determine one or more parameters based on the leakage flux. The one or more parameters include at least one of current level, rotor position, temperature, or magnetization state.

[0015] Among other features, the first control module is configured to determine the current level based on the leakage flux.

[0016] Among other features, the first control module is configured to determine the rotor position based on the leakage flux.

[0017] Among other features, the first control module is configured to determine the temperature based on the leakage flux.

[0018] Among other features, the first control module is configured to determine the magnetization state based on the leakage flux.

[0019] Among other features, the one or more point field detectors include at least three point field detectors. The first control module is configured to determine the current level, the rotor position, the temperature, and the magnetization state based on the outputs of the three point field detectors.

[0020] Among other features, the propulsion system further includes a current sensor, an adder, a first converter, and a second converter. The current sensor is configured to detect the current in each of the three phases of the motor. The adder is configured to determine the difference between the leakage flux and a desired amount of leakage flux. The first converter is configured to convert the difference into the rotor position. The second converter is configured to determine the desired amount of leakage flux based on the rotor position and the current signal output from the current sensor.

[0021] Among other features, the propulsion system further includes a position sensor, an adder, a converter, and a rotor salient pole corrector module. The position sensor is configured to detect the position of at least one of the shaft or the rotor. The adder is configured to determine the difference between the leakage flux and a desired amount of leakage flux. The converter is configured to convert the difference into a dq current signal. The rotor salient pole corrector module is configured to (i) determine the desired amount of leakage flux based on the dq current signal and the position of the at least one of the shaft or the rotor, and (ii) determine the desired amount of leakage flux while compensating for at least one of different magnetic reluctances of the d-axis and q-axis of the motor, different magnetic fields associated with the d-axis and q-axis, or differences in the d and q current levels.

[0022] Among other features, the propulsion system also includes a sensor. The sensor is separate from the motor and configured to detect (i) the position of the shaft, or (ii) the current level, which is the amount of current in a phase of the motor. The first control module is configured to determine at least one of the position of the shaft or the current level of the phase of the motor based on the leakage flux as a redundancy check to verify the sensor's output.

[0023] Among other features, the propulsion system further includes a second control module configured to perform at least one of the following: diagnostics or predictions of the motor based on the leakage flux.

[0024] The present invention also includes the following technical solutions.

[0025] Option 1. A motor disposed within a housing, the motor comprising:

[0026] The stator receives current from the inverter;

[0027] A rotor, which is connected to a shaft and rotates the shaft based on the magnetic field generated by the stator; and

[0028] One or more point field detectors configured to detect leakage magnetic flux within the housing.

[0029] The stator, the rotor, and the one or more point field detectors are disposed within the housing.

[0030] Option 2. The motor according to Option 1, wherein the one or more point field detectors are disposed on the rotor.

[0031] Option 3. The motor according to Option 1, wherein the one or more point field detectors are disposed on the stator.

[0032] Option 4. The motor according to Option 1, wherein the one or more point field detectors are disposed radially outside the stator and radially inside the housing.

[0033] Option 5. The motor according to Option 1, wherein the one or more point field detectors are disposed on the radial outer surface of the stator.

[0034] Option 6. The motor according to Option 1, wherein the one or more point field detectors are disposed on the radial inner surface of the housing.

[0035] Option 7. The motor according to Option 1, wherein:

[0036] The one or more point field detectors are embedded in a dielectric material; and

[0037] The dielectric material is disposed between the stator and the housing.

[0038] Option 8. The motor according to Option 1, wherein the one or more point field detectors comprise a plurality of semiconductor chip-level devices.

[0039] Option 9. The motor according to Option 1, wherein the one or more point field detectors include a Hall effect sensor isolated by current.

[0040] Option 10. The motor according to Option 1, wherein the one or more point field detectors include a magnetoresistive sensor isolated by current.

[0041] Option 11. A propulsion system, comprising:

[0042] The motor according to Scheme 1; and

[0043] A first control module is configured to determine one or more parameters based on leakage flux, wherein the one or more parameters include at least one of current level, rotor position, temperature, or magnetization state.

[0044] Option 12. The propulsion system according to Option 11, wherein the first control module is configured to determine the current level based on the leakage flux.

[0045] Option 13. The propulsion system according to Option 11, wherein the first control module is configured to determine the rotor position based on the leakage flux.

[0046] Option 14. The propulsion system according to Option 11, wherein the first control module is configured to determine the temperature based on the leakage flux.

[0047] Option 15. The propulsion system according to Option 11, wherein the first control module is configured to determine the magnetization state based on the leakage flux.

[0048] Option 16. The propulsion system according to Option 11, wherein:

[0049] One or more point field detectors include at least three point field detectors; and

[0050] The first control module is configured to determine the current level, the rotor position, the temperature, and the magnetization state based on the outputs of the three point field detectors.

[0051] Option 17. The propulsion system according to Option 11 further includes:

[0052] Multiple current sensors are configured to detect the current in each of the three phases of the motor.

[0053] An adder configured to determine the difference between the leakage flux and a desired amount of leakage flux;

[0054] A first converter configured to convert the difference into the rotor position; and

[0055] The second converter is configured to determine the expected amount of leakage flux based on the rotor position and the current signal output of the current sensor.

[0056] Option 18. The propulsion system according to Option 11 further includes:

[0057] A position sensor configured to detect the position of at least one of the shaft or the rotor;

[0058] An adder configured to determine the difference between the leakage flux and a desired amount of leakage flux;

[0059] A converter configured to convert the difference into a dq current signal; and

[0060] A rotor salient pole corrector module configured to (i) determine the expected amount of leakage flux based on the dq current signal and the position of at least one of the shaft or the rotor, and (ii) determine the expected amount of leakage flux while compensating for at least one of different magnetic reluctances of the d-axis and q-axis of the motor, different magnetic fields associated with the d-axis and q-axis, or differences in the d and q current levels.

[0061] Option 19. The propulsion system according to Option 11 further includes a sensor separate from the motor, and the sensor is configured to detect (i) the position of the shaft, or (ii) the current level, the current level being the amount of current through a phase of the motor.

[0062] The first control module is configured to determine at least one of the position of the shaft or the current level of the phase of the motor based on the leakage flux as a redundancy check to verify the output of the sensor.

[0063] Option 20. The propulsion system according to Option 11 further includes a second control module configured to perform at least one of the diagnostics or predictions of the motor based on the leakage flux.

[0064] Other aspects of the applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0065] This disclosure will be more fully understood through a detailed description and accompanying drawings, in which:

[0066] Figure 1 It is a functional block diagram and schematic diagram of an exemplary propulsion system including a motor having a point field detector (PFD) circuit according to the present disclosure;

[0067] Figure 2 This is a cross-sectional view of an exemplary portion of a motor, illustrating a point field detector (PFD) according to this disclosure.

[0068] Figure 3 This is a signal diagram of an exemplary feedback system for determining rotor position based on leakage flux detected by the PFD, according to the present disclosure;

[0069] Figure 4 This is an exemplary simulation plot of leakage flux relative to time, as detected by one or more PFDs;

[0070] Figure 5 Is using Figure 3 The feedback system corresponds to Figure 4 An exemplary simulation diagram of the rotor position versus time for leakage flux;

[0071] Figure 6 This is a signal diagram of an exemplary feedback system for determining the dq current based on leakage flux detected by the PFD, according to the present disclosure.

[0072] Figure 7 Is using Figure 6 An example diagram of the leakage flux of the space vector at the first load level of the feedback system;

[0073] Figure 8 Is using Figure 6Another example diagram of the leakage flux of the space vector at the second load level of the feedback system; and

[0074] Figure 9 Is using Figure 6 An example diagram of the leakage flux of the space vector at the third load level of the feedback system.

[0075] In the accompanying drawings, reference numerals may be used repeatedly to identify similar and / or identical elements. Detailed Implementation

[0076] Propulsion systems in vehicles that include one or more electric motors may require current and rotor position detection for torque control. The motor's input current level and rotor position are used to generate and orient the current complex space vector in order to set the motor's output torque level. Torque control may also require the time derivative of the rotor position (i.e., the rotor speed) to set the motor's input current level for maximum torque per ampere (MTPA) and field weakening operation. Precise current levels and rotor positions are required to accurately set the motor's torque and power output levels.

[0077] The vehicle's propulsion system may include various sensors for detecting the state of one or more electric motors (e.g., one or more integrated permanent magnet (IPM) motors). These sensors may include Hall effect sensors for detecting the phase current level of the electric motor, temperature sensors for detecting the temperature of the electric motor, and resolvers (e.g., reluctance resolvers) for detecting the position of the electric motor's rotor. As an example, three Hall effect sensors may be positioned on current lines extending from the inverter to the corresponding IPM motor to detect the level of the three-phase input current of the IPM motor. The resolver may be located within the IPM motor, attached to the IPM motor, or indirectly attached to the IPM motor via a shaft and / or other coupling members. The resolver needs to be mounted on a shaft inside or outside the IPM motor. Hall effect sensors and resolvers can be expensive and bulky, which can be an obstacle to achieving power density targets. Depending on their implementation location, the resolver may also be exposed to automatic transmission fluid (ATF) and therefore require certain types of electrical connections that can be exposed to ATF without experiencing electrical short circuits. As an example, temperature sensors may include thermocouples and / or other types of temperature sensors.

[0078] Examples described in this article include motors with point field detectors (PFDs) used to detect leakage flux within the motor housing. These PFDs are implemented within the housing and include low-cost, lightweight hardware with magnetoresistive and / or Hall effect sensing capabilities. The PFD does not include moving parts and / or a magnetic core and extracts information from existing electromagnetic fields. Multiple motor parameters are determined based on the output signal from the PFD. Motor control, diagnostics, and / or predictive operations are performed based on the determined parameters.

[0079] Figure 1 An exemplary propulsion system 100 is shown, which includes a motor 102 with a point field detector (PFD) circuitry 104. Although the motor 102 is shown as an IPM motor, it could be a surface permanent magnet motor or other types of electric motor. While various examples of motors are disclosed herein, these examples are applicable to other motors as well. For example, the PFD disclosed herein could be implemented in a generator or other motor, and various information as disclosed herein could be extracted from the output of the PFD.

[0080] PFD circuit 104 may be attached to and included therein at least a portion of the housing of, for example, motor 102. PFD circuit 104 may include one or more PFDs. Examples of PFDs are shown in... Figure 2 As shown in the diagram. A PFD can refer to a device configured to detect leakage flux and / or magnetic field. The leakage flux can refer to flux that does not follow a specific expected path in a magnetic circuit and is not used for operation. The leakage flux can be stator leakage flux and / or rotor leakage flux. A PFD can include Hall effect sensors, magnetoresistive sensors, anisotropic magnetoresistive (AMR) sensors, tunneling magnetoresistive sensors, and giant magnetoresistive sensors. In one embodiment, the PFD is a semiconductor chip-level sensor configured to be disposed within the housing of motor 102. A PFD can include (i) a one-dimensional PFD, each for measuring radial or tangential leakage flux, and / or (ii) a two-dimensional PFD, each for measuring radial and tangential leakage flux. Each two-dimensional PFD can include two one-dimensional PFDs.

[0081] The propulsion system 100 is used to drive the vehicle 110 and also includes a power source 112 (e.g., a battery pack), an inverter 114, an axle 116, an axle 118 including a differential 121, and wheels 123. The inverter 114 converts direct current (DC) voltage into three-phase alternating current (AC) to power the motor 102. The motor 102 drives the axle 116, which in turn drives the axle 118.

[0082] The propulsion system 100 also includes a vehicle control module 120, a current control module 122, and a driver 124. The vehicle control module 120 can generate a torque request signal. This torque request signal can be generated based on, for example, a torque commanded by an accelerator 126 (if included). The current control module 122 can control the driver 124 based on this torque request signal. For example, the driver 124 can generate a pulse width modulation (PWM) signal based on the output of the current control module 122 to control the state of the transistors in the inverter 114.

[0083] The current control module 122 controls the driver 124 based on the output from sensors. These sensors may include current sensors (e.g., Hall effect sensor 130), resolver 132, temperature sensor 134, and / or the PFD of the PFD circuit 104. The current sensors may include sensors other than Hall effect sensors. The current control module 122 receives leakage flux current signals from the PFD. The PFD signal may be provided, for example, via one or more signal lines. X signal lines are shown. Each PFD may include one or more signal lines. Each two-dimensional PFD may include two signal lines. Furthermore, the signal from the PFD may be a differential signal, each of which includes two lines. Information on the signal lines, including voltage, current level, maximum and minimum voltage, maximum and minimum current level, frequency, duty cycle, etc., can be monitored and / or extracted, and can be used to determine leakage flux and other parameters.

[0084] The current control module converts the three-phase current phase signals Ia, Ib, and Ic of the motor into current vector signals Id and Iq. The current control module 122 determines how much current is flowing and how much current is needed (or requested), and modifies the input current level of the motor 102 by adjusting the output current vector voltage signal provided to the driver 124. This is based on: (i) the current vector signals Id and Iq; (ii) the PFD signal; (iii) the position signal from the rotary transformer 132; and (iv) the torque request signal from the vehicle control module 120.

[0085] The PFD can be used to replace one or more of sensors 130, 132, and 134 and / or for redundancy purposes. The PFD can be used to back up and / or verify the outputs of sensors 130, 132, and 134. The PFD measures the magnetic flux leakage current, which includes information indicating: (i) the current level of the stator of motor 102; (ii) the position of the rotor of motor 102; (iii) the temperature of motor 102 and / or its components, such as the temperature of the rotor of motor 102; and (iv) the magnetization state of motor 102. The magnetization state of motor 102 refers to the magnetization state of the magnets of motor 102.

[0086] In one embodiment, sensors 130, 132, and 134 and a PFD are included. The PFD can be used for redundancy purposes to provide the same or similar information provided by sensors 130, 132, and 134. The information provided by sensors 130, 132, and 134 can be derived from the signal generated by the PFD. Table 1 shows the information that can be collected and / or derived from the outputs of sensors 130, 132, 134, and the PFD:

[0087]

[0088] Table 1 – Sensing parameters and corresponding possible sensors.

[0089] The leakage flux Φ measured by each PFD is equal to the permanent magnetic flux j at the PFD location. m The permanent magnet flux j is a function of the stator current vector Idq, the rotor position θ, and the permeability μ of the ferromagnetic material of the motor, as shown in Equation 1. m Equal to rotor position θ, rotor temperature T, and motor magnetization state J e The permeability μ is a function of the current vector Idq, the rotor position θ, and the temperature T, as shown in Equation 2. The permeability μ is also equal to the magnetic flux density B divided by the magnetic field density H:

[0090] Φ = F{j m , Idq, θ, μ} (1)

[0091] j m = F{θ, T, J e} (2)

[0092] μ = F{Idq, θ, T} (3).

[0093] Substituting equations 2 and 3 into equation 1 yields equation 4, where the leakage flux Φ at PFD is equal to the rotor position θ, the rotor temperature T, and the magnetization state J. e Functions of the current vector Idq:

[0094] Φ = F{θ, T, J e , Idq} (4).

[0095] The leakage flux Φ can be measured by any number of PFDs and has the property of indicating other parameters, such as rotor position θ, temperature T, and magnetization state J. eThe rotor position θ can be measured by a resolver and / or using (i) two or more single-dimensional PFDs or (ii) one or more double-dimensional PFDs. The current vector Idq can be determined based on the outputs of the resolver and (i) three current sensors (e.g., Hall effect sensors) attached to the current line extending between the inverter and the motor; (ii) the outputs from three or more single-dimensional PFDs; and / or (iii) the outputs from two or more double-dimensional PFDs. The rotor temperature T can be determined (i) via a thermocouple (or other temperature sensor) and / or (ii) based on the outputs from one or more PFDs. Magnetization state J e The magnetization state J can be estimated based on (i) the output of the current sensor and the rotor position, and / or (ii) the output of one or more PFDs. e It can be used to estimate rotor temperature.

[0096] Each of the PFDs 202, 204, and / or other PFDs mentioned herein can be a unidirectional or bidirectional PFD. Each unidirectional PFD can be used to detect magnetic fields and leakage flux in the X or Y direction. Each bidirectional PFD can be used to detect magnetic fields and leakage flux in both the X and Y directions. The X and Y directions can refer to the radial and tangential directions in a cylindrical coordinate system.

[0097] Any one of the parameters—leakage flux, rotor position, current vector, rotor temperature, and magnetization state—can be determined based on the other four parameters. This allows for the removal of, for example, a current sensor or a resolver, and alternatively, the inclusion of one or more PFDs. As an example, each current sensor and / or resolver can be replaced by one or more PFDs. In one embodiment, the current sensor is replaced by a PFD. The PFD and resolver are used to estimate the current through the stator. In another embodiment, the resolver is replaced by one or more PFDs and the rotor position is estimated based on the output of the PFDs.

[0098] When multiple PFDs are included to provide sufficient degrees of freedom and unique information, the current sensor and resolver can be eliminated. As an example, 6-7 PFDs can be included to measure leakage flux and estimate rotor position, rotor speed, current level (or current vector), rotor temperature, and / or the motor's magnetization state. The rotor speed can be determined based on the rotor position.

[0099] Figure 2 A motor (e.g.) is shown. Figure 1A portion 200 of a motor 102 is illustrated, comprising an assembly (or array) of point field detectors (PFDs) 202, 204. Portion 200 may be associated with a single pole of a multi-pole motor. Although a motor is shown, PFDs 202, 204 may be similarly implemented on other motors. The motor includes a rotor 206 and a stator 208 and may include a housing 210. Housing 210 may be a housing of the motor and / or motor assembly, or it may be a housing of another device, such as a transmission, in which the motor (or motor) is disposed. In one embodiment, the motor is disposed in the housing of a transmission. The motor (or motor) may be disposed within the housing of another device without a dedicated housing merely enclosing the motor (or motor). The rotor 206 is attached to and rotates a shaft 212. Although two sets of PFDs are shown, any number of sets of PFDs may be included. Each set of PFDs may include one or more PFDs. The rotor includes magnets (e.g., magnet 214). The stator 208 includes stator windings (or conductors) 216. Any number of PFD groups (or arrays) can be included within housing 210.

[0100] Although the two sets of PFDs are shown as being disposed outside the stator 208, the PFDs may be located in other locations, such as on the rotor 206 and / or the stator 208. The PFDs may be arranged in rows and / or columns. In one embodiment, the PFDs are arranged in a ring-like pattern circumferentially around the stator 208. In the illustrated example, the PFDs are disposed between the stator 208 and the housing 210. The PFDs may be attached to the outer peripheral surface 220 of the stator 208 or to the inner surface 222 of the housing 210. The PFDs may be disposed on or outside portions of the motor corresponding to one or more poles of the motor. As an example, the motor may have 2, 4, 8, 16, etc., poles, and the PFDs may be disposed on portions of the motor corresponding to these poles or radially outside of them. As shown, the PFDs may be disposed in the space 224 between the stator and the housing 210. In yet another embodiment, the PFDs are disposed within a predetermined distance (e.g., 2-3 millimeters (mm)) of the outer peripheral surface 220 of the stator 208.

[0101] In one embodiment, leakage flux (or leakage magnetic flux) is detected radially outside the core 230 of stator 208 using an integrated PFD. Parameters such as current level, rotor position, rotor speed (or rate), and rotor magnetization state can be derived and / or estimated based on the PFD output. Leakage flux is naturally present in an operating motor and contains cross-coupled information about rotor and stator parameters. As mentioned above, the PFD can be a chip-level sensor that is inexpensive, small in size and weight, and has no moving parts. The PFD is housed within a housing 210 and is not exposed to liquids, such as automatic transmission fluid, and therefore does not require specific electrical connections suitable for such environments. The housing 210 may be electrically grounded and / or connected to a ground reference.

[0102] The output of the PFD can be provided to analog hardware circuitry and / or directly to the current control module 122. This analog hardware circuitry can (i) be connected between the PFD and the current control module 122, and (ii) filter, process signals, and / or determine one or more parameters based on the PFD's output. The analog hardware circuitry can be part of or separate from the current control module 122. The analog hardware circuitry and / or the current control module 122 can be implemented as circuitry disposed on and / or attached to the housing 210. The analog hardware circuitry and / or the current control module 122 can be implemented separately from the motor and therefore separately from the housing 210. External implementation attached to the housing 210 and / or the analog hardware circuitry and current control module 122 provides easy access to the hardware controlling the operation of the motor. The analog hardware circuitry and / or the current control module 122 can be implemented within a protective housing and not exposed to fluids, such as automatic transmission fluids.

[0103] PFD can be as follows Figure 2 The PFD is isolated as shown, allowing for motor control, diagnostics, and prediction. In another embodiment, the PFD is fixed and performs leakage flux sensing. In one embodiment, a dielectric material 211 is disposed between the stator 208 and the PFD, such that the PFD has complete current isolation. The PFD may be at least partially disposed in and / or surrounded by the dielectric material 211. The PFD is isolated from the motor's stator 208, rotor 206, and inverter (e.g., Figure 1 Conductor isolation of inverter 114.

[0104] Control, diagnosis, and prediction can be achieved through the current control module 122 and / or the vehicle control module 120. The current control module 122 can be based on... Figure 1 Sensors 130, 132, 134 and / or PFD (e.g., Figure 2 The current control module 122 collects and / or derives information from the output of the PFDs 202, 204 to control current and voltage levels, torque output, and motor speed. The current control module 122 can perform diagnostic and / or predictive operations to detect and identify motor degradation, malfunctions, and / or faults. This is based on the output of the PFD and / or, for example... Figure 1 This is achieved through the outputs of other sensors 130, 132, and 134. The vehicle control module 120 can execute countermeasures in response to the results of diagnostic and predictive operations, such as generating visual or audible indication signals of motor status via indicator 240, limiting motor speed, limiting motor operation for a predetermined time period, reducing motor speed to a predetermined speed or zero, and / or executing some other countermeasure. Indicator 240 can be a display, an audio device, a transmitter for wirelessly transmitting information to a remote device, and / or other indicators.

[0105] Figure 3 An exemplary feedback system 300 is shown for determining rotor position based on leakage flux detected by a PFD. The feedback system 300 can be used to... Figure 1-2 The current control module 122 and / or vehicle control module 120 are used to perform this. The feedback system 300 may include an adder 302, a leakage flux-rotor position converter 304, and a current-flux converter 306. The adder 302 can determine (i) the difference 312 between the amount of leakage flux 308 detected by the PFD and (ii) the expected amount of leakage flux 310 based on the amount of stator current. The leakage flux 308 may be at or near the stator outer diameter (OD) and includes radial and tangential components Br and Bt of the flux density.

[0106] As an example, the PFD can be set on the outside of the stator, such as Figure 2 As shown in the figure. The difference 312 can represent the stator OD leakage flux (or the amount of leakage flux measured at or near the OD of the stator) and is based on rotor rotation.

[0107] The leakage flux-to-rotor position converter 304 can determine the rotor position 314 based on the difference 312 provided by the adder 302. The current-to-flux converter 306 can determine the expected leakage flux 310 based on the stator current. The current-to-flux converter 306 can (i) determine the current vector Idq (or current vectors Id and Iq) based on the rotor position 314 and the motor current signal 316, and subsequently (ii) determine the expected leakage flux 310 based on the current vector Idq. The motor current signal may include the three-phase Ia, Ib, and Ic current signals of the motor. The motor current signal may be generated by the aforementioned current sensor. The current-to-flux converter 306 can be used for load decoupling purposes and for current observer calibration and regulation purposes.

[0108] Feedback system 300 may (i) receive or detect net leakage flux at or near the OD of the stator using a two-dimensional PFD, (ii) use information from a current sensor to split the cross-coupled net leakage flux into rotor and stator components, (iii) split the rotor leakage flux into tangential and radial components, and (iv) use an arctangent (or anti-tangential) and / or observer-based method to obtain the absolute rotor position. As an example, leakage flux-rotor position converter 304 may use the arctangent of the radial signal (or leakage flux radial component) divided by the tangential signal (or leakage flux tangential component) to determine the angle indicating the rotor position.

[0109] Figure 4 A simulation plot of leakage flux versus time, as detected by one or more PFDs, is shown. Figure 4This is an example of an unloaded condition, where zero current flows through the motor stator. The figure includes radial and tangential flux density curves 400, 402 and the corresponding ideal curves 404, 406. For conditions with applied load and increased current to the stator, figures will be provided... Figure 4 The different sine curves are shown. In the performed simulation, the radial and tangential leakage fields were captured using finite element analysis (FEA) and plotted after amplitude scaling. Rotor position information can be extracted from the radial and tangential fields using the arctangent method. This is in Figure 5 As shown, it includes corresponding to Figure 4 leakage flux and using Figure 3 Simulation diagram of rotor position versus time in the feedback system. Figure 5 This includes rotor position curve 500 and position reference curve 502. The non-ideal nature of the field results in a mechanical error of less than 1°. Figure 4-5 A drawing is provided as an example to illustrate that leakage flux exists outside the stator and is within the detectable range of the PFD.

[0110] Figure 6 A feedback system 600 is shown for determining the dq current based on the leakage flux detected by the PFD. The feedback system 600 can be used to... Figure 1-2 The current control module 122 and / or vehicle control module 120 perform this operation. The feedback system 600 may include an adder 602, a leakage flux-to-current converter 604, and a rotor salient pole corrector module 606. The adder 602 determines a difference 612 between the leakage flux 608 detected by one or more PFDs and an expected amount of leakage flux 610 associated with rotor rotation. The leakage flux 608 may be detected at or near the outer periphery of the stator (or stator OD). The expected leakage flux 610 may include the radial and tangential components Br and Bt of the flux density.

[0111] The leakage flux-to-current converter 604 determines the dq current 614 based on the difference 612. The difference 612 can be the leakage flux at or near the stator OD and corresponds to the level of the stator current. The rotor salient pole corrector module 606 determines the expected leakage flux 610 based on the dq current 614 and the motor shaft position sensor signal 616. The motor shaft position sensor signal 616 can indicate the rotor position, which can be indicated by a resolver.

[0112] The rotor saliency corrector module 606 provides rotor position decoupling and compensates for different field and dq current levels. The motor's d-axis and q-axis can have different associated magnetic reluctances, resulting in different magnetic fields in different directions, a phenomenon known as rotor saliency. The rotor saliency corrector module 606 compensates for these differences by generating a desired leakage flux to compensate for the difference obtained via adder 602.

[0113] Figure 7-9 The use of each is shown separately. Figure 6 The feedback system is plotted for the leakage flux of the space vector at the first, second, and third exemplary load levels. These plots compare the tangential magnetic flux density Bt at the space vector axis β with the radial magnetic flux density Br at the space vector axis α. Figure 7 Curves for different current angles γ, including 0°, 45°, 90°, 135°, and 180°, are 700, 702, 704, 706, and 708. Figure 8 Curves for different current angles γ, including 0°, 45°, 135°, and 180°, are 800, 802, 804, 806, and 808. Figure 9 Curves for different current angles γ, including 0°, 45°, 135°, and 180°, are 900, 902, 904, 906, and 908. Figure 7 This is a low-load example, where the current load is 50 Arms. Figure 8 This is an example of an intermediate load, where the current load is 350 Arms. Figure 9 This is a high-load example, where the current load is 650 Arms.

[0114] The examples disclosed above include PFD sensing in a motor, and include measuring and / or determining rotor and stator states and may include performing diagnostics. The integrated PFD is isolated from and does not experience high voltage and current, and is therefore highly reliable. The voltage and current levels experienced by the PFD are similar to those experienced by, for example, control modules 120, 122. Rotor states include rotor position, rotor speed (or rate), magnetization state, and motor temperature. Motor temperature may be the temperature of the rotor. Stator states include the current levels of the three phases of the motor and / or the dq current level. Diagnostics include stator and rotor faults, including faults associated with the stator windings and / or the permanent magnets of the rotor.

[0115] The methods described above may include: (i) physics-based decoupling; (ii) observers; (iii) Kalman filters and corresponding filtering; and (iv) the use of lookup tables when determining parameters based on other parameters. Modules 120 and 122 may include one or more neural networks that are structured and / or recursive, and are used to determine certain parameters based on other parameters. The methods may include template-based saliency tracking and image tracking.

[0116] The examples provide a low-cost and compact sensing system for any surface or interior of a permanent magnet motor without altering the rotor and / or stator design. Sensing systems for detecting existing leakage flux on and / or near the OD of the stator of a motor using a PFD are disclosed. Examples include: correlations between leakage flux and rotor positioning, rotor speed, magnetized stator state, and temperature; correlations between leakage flux and dq current levels; and correlations between leakage flux and stator and rotor faults and anomalies.

[0117] The foregoing description is merely illustrative in nature and is in no way intended to limit this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in many forms. Therefore, while this disclosure includes specific examples, its actual scope should not be limited thereto, as other modifications will become apparent from a study of the drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of this disclosure may be implemented and / or combined with features in any other embodiment, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitution of one or more embodiments for each other remains within the scope of this disclosure.

[0118] Spatial and functional relationships between components (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connected,” “joined,” “coupled,” “adjacent,” “next to,” “on top,” “above,” “below,” and “set.” Unless explicitly described as “direct,” the relationship between first and second components described in the above disclosure can be a direct relationship where no other intermediary components exist between the first and second components, or an indirect relationship (spatially or functionally) where one or more intermediary components exist between the first and second components. As used herein, the phrase “at least one of A, B, and C” should be interpreted as referring to logic using non-exclusive OR (A OR B OR C) and should not be interpreted as referring to “at least one of A, at least one of B, and at least one of C.”

[0119] In the accompanying drawings, the direction of the arrows, as indicated by their tips, typically illustrates the flow of information (e.g., data or instructions) of interest to the illustration. For example, when components A and B exchange various types of information, but the information transmitted from component A to component B is relevant to the illustration, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for or acknowledgment of receipt of the information to component A.

[0120] In this application, which includes the following limitations, the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, or include, any of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed analog / digital discrete circuit; digital, analog, or mixed analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuitry (shared, dedicated, or grouped) that executes code; memory circuitry (shared, dedicated, or grouped) that stores code executed by the processor circuitry; other suitable hardware components that provide the aforementioned functionality; or, for example, some or all of the above in a system-on-a-chip.

[0121] A module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces for connecting to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module in this disclosure may be distributed across multiple modules connected via the interface circuits. For example, multiple modules may allow for load balancing. In another example, a server (also referred to as a remote or cloud) module may perform some functions on behalf of a client module.

[0122] As used above, the term "code" can include software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuit" covers a single-processor circuit that executes some or all of the code from multiple modules. The term "group processor circuit" covers a processor circuit that, in conjunction with additional processor circuitry, executes some or all of the code from one or more modules. References to multiple processor circuits cover multiple processor circuits on a discrete die, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term "shared memory circuit" covers a single-memory circuit that stores some or all of the code from multiple modules. The term "group memory circuit" covers a memory circuit that, in conjunction with additional memory, stores some or all of the code from one or more modules.

[0123] The term "memory circuit" is a subset of the term "computer-readable medium." As used herein, the term "computer-readable medium" does not cover transient electrical or electromagnetic signals propagated through a medium (e.g., on a carrier wave); therefore, the term "computer-readable medium" can be considered tangible or non-transient. Non-limiting examples of non-transient, tangible computer-readable media are non-volatile memory circuits (e.g., flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (e.g., static random access memory circuits or dynamic random access memory circuits), magnetic storage media (e.g., analog or digital magnetic tape or hard disk drives), and optical storage media (e.g., CDs, DVDs, or Blu-ray discs).

[0124] The apparatus and methods described in this application can be implemented, in part or in whole, by a dedicated computer created by configuring a general-purpose computer to perform one or more specific functions embodied in a computer program. The aforementioned function blocks, flowchart components, and other elements serve as a software specification that can be translated into a computer program through the routine work of a technician or programmer.

[0125] The computer program includes processor-executable instructions stored on at least one non-transitory, tangible computer-readable medium. The computer program may also include or rely on stored data. The computer program may encompass a basic input / output system (BIOS) that interacts with the hardware of a special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0126] The computer program may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated from the source code by a compiler; (iv) source code for execution by an interpreter; (v) source code for compilation and execution by a just-in-time compiler, etc. By way of example only, the source code may be written using syntax from languages ​​including: C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, JavaScript®, HTML5 (Hypertext Markup Language version 5), Ada, ASP (Dynamic Server Web Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®.

Claims

1. A propulsion system, comprising: A motor disposed within a housing, the motor comprising: The stator receives current from the inverter; A rotor, which is connected to a shaft and rotates the shaft based on the magnetic field generated by the stator; and One or more point field detectors, which do not include moving parts and / or magnetic cores, and extract information from existing electromagnetic fields, the point field detectors being configured to detect leakage flux within the housing. The stator, the rotor, and the one or more point field detectors are disposed within the housing; The propulsion system also includes: A position sensor configured to detect the position of at least one of the shaft or the rotor; An adder configured to determine the difference between the leakage flux and a desired amount of leakage flux; A converter configured to convert the difference into a dq current signal; and A rotor salient pole corrector module configured to (i) determine the expected amount of leakage flux based on the dq current signal and the position of at least one of the shaft or the rotor, and (ii) determine the expected amount of leakage flux while compensating for at least one of different magnetic reluctances of the d-axis and q-axis of the motor, different magnetic fields associated with the d-axis and q-axis, or differences in the d and q current levels.

2. The propulsion system of claim 1, wherein, The one or more point field detectors are mounted on the rotor.

3. The propulsion system of claim 1, wherein, The one or more point field detectors are mounted on the stator.

4. The propulsion system of claim 1, wherein, The one or more point field detectors are disposed radially outside the stator and radially inside the housing.

5. The propulsion system of claim 1, wherein, The one or more point field detectors are disposed on the radial outer surface of the stator.

6. The propulsion system of claim 1, wherein, The one or more point field detectors are disposed on the radial inner surface of the housing.

7. The propulsion system according to claim 1, wherein: The one or more point field detectors are embedded in a dielectric material; and The dielectric material is disposed between the stator and the housing.

8. The propulsion system of claim 1, wherein, The one or more point field detectors include multiple semiconductor chip-level devices.

9. The propulsion system of claim 1, wherein, The one or more point field detectors include Hall effect sensors that are isolated by current.

10. The propulsion system according to claim 1, wherein, The one or more point field detectors include magnetoresistive sensors that are isolated by current.

11. A propulsion system, comprising: A motor disposed within a housing, the motor comprising: The stator receives current from the inverter; A rotor, which is connected to a shaft and rotates the shaft based on the magnetic field generated by the stator; and One or more point field detectors, which do not include moving parts and / or magnetic cores, and extract information from existing electromagnetic fields, the point field detectors being configured to detect leakage flux within the housing. The stator, the rotor, and the one or more point field detectors are disposed within the housing; The propulsion system also includes: A first control module is configured to determine one or more parameters based on leakage flux, wherein the one or more parameters include at least one of current level, rotor position, temperature, or magnetization state. A position sensor configured to detect the position of at least one of the shaft or the rotor; An adder configured to determine the difference between the leakage flux and a desired amount of leakage flux; A converter configured to convert the difference into a dq current signal; and A rotor salient pole corrector module configured to (i) determine the expected amount of leakage flux based on the dq current signal and the position of at least one of the shaft or the rotor, and (ii) determine the expected amount of leakage flux while compensating for at least one of different magnetic reluctances of the d-axis and q-axis of the motor, different magnetic fields associated with the d-axis and q-axis, or differences in the d and q current levels.

12. The propulsion system according to claim 11, wherein, The first control module is configured to determine the current level based on the leakage flux.

13. The propulsion system according to claim 11, wherein, The first control module is configured to determine the rotor position based on the leakage flux.

14. The propulsion system according to claim 11, wherein, The first control module is configured to determine the temperature based on the leakage flux.

15. The propulsion system according to claim 11, wherein, The first control module is configured to determine the magnetization state based on the leakage flux.

16. The propulsion system according to claim 11, wherein: One or more point field detectors include at least three point field detectors; and The first control module is configured to determine the current level, the rotor position, the temperature, and the magnetization state based on the outputs of the three point field detectors.

17. The propulsion system according to claim 11, further comprising: Multiple current sensors are configured to detect the current in each of the three phases of the motor. An adder configured to determine the difference between the leakage flux and a desired amount of leakage flux; A first converter is configured to convert the difference into the rotor position; as well as The second converter is configured to determine the expected amount of leakage flux based on the rotor position and the current signal output of the current sensor.

18. The propulsion system of claim 11, further comprising a sensor separate from the motor, and said sensor being configured to detect (i) the position of the shaft, or (ii) the current level, said current level being the amount of current through a phase of the motor. in, The first control module is configured to determine at least one of the position of the shaft or the current level of the phase of the motor based on the leakage flux as a redundancy check to verify the output of the sensor.

19. The propulsion system of claim 11, further comprising a second control module configured to perform at least one of diagnostics or predictions of the motor based on the leakage flux.

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