Bandwidth-split harmonic regulation of improved acoustic behavior of electric drive systems

Abstract

A method for controlling operation of a rotating electric machine includes receiving, via a bandwidth partitioned harmonic compensation regulator (HCR) of a controller, an instruction torque and a rotational speed of the machine, and using the instruction torque and the rotational speed to calculate dq harmonic compensation currents and voltages for one or more predetermined harmonic orders via the HCR in response to an enable condition. The harmonic compensation currents and voltages cancel torque and current fluctuations in the one or more predetermined harmonic orders. The method can include injecting acoustic tones at the predetermined harmonic orders. The method also includes adding the dq harmonic compensation currents and voltages to dq current and voltage instructions, respectively, to produce adjusted dq current and voltage instructions. The adjusted dq current and voltage instructions are then used to control the machine.

Description

Background Technology

[0001] Rotating electric motors are used in vehicle powertrains and other electric drive systems to transmit motor torque to connected loads. In radial flux motors with a rotor and a wound stator, the rotor is surrounded by the stator and separated from it by a radial air gap. When the stator's excitation windings are sequentially energized by a high-voltage power supply, the rotor and the integrally connected rotor shaft rotate in unison; this high-voltage power supply is typically in the form of a power inverter and a high-voltage battery pack. The motor torque generated by the energized motor is transmitted to the connected load to perform work, such as generating electricity, turning cranks and starting internal combustion engines, and / or, depending on the application, powering one or more wheels, propeller blades, drive belts, or other connected mechanical loads.

[0002] Space flux harmonics and power inverter nonlinearities can cause electric drive systems to experience periods of undesirable torque and current ripple. Collective ripple phenomena, often arising from mechanical design factors such as stator-rotor misalignment, tend to interact with drivetrain dynamics to produce undesirable drivetrain vibrations and other noise, vibration, and harshness (NVH) effects. Torque ripple specifically refers to the periodic variation in the total output torque of the motor, which includes the average output torque produced by the motor and the associated torque ripple. Similarly, current ripple describes the ripple caused by rotation in the motor drive current fed into the stator field windings. Current ripple tends to exacerbate the NVH effects of torque ripple due to factors such as electromagnetic interference and acoustic noise caused by current ripple. Summary of the Invention

[0003] This document discloses a system, associated control logic, and method for controlling the operation of a rotating electric motor within an electric drive system, with the aim of reducing or ideally eliminating multiple harmonic orders of the aforementioned torque and current fluctuations. Additional benefits include reducing acoustic noise and other mechanical noise, vibration, and noise and harshness (NVH) effects, or, if desired, introducing specific acoustic tones of specific harmonic orders to disperse or complement existing harmonic orders. Therefore, this control scheme is highly customizable to adjust harmonic handling within the electric drive system in a manner suitable for the application.

[0004] The teachings presented herein provide bandwidth partitioning for a harmonic regulator, which is the logic block of the resident controller that generates the final control voltage command and transmits the voltage command to the motor. As mentioned above, the solution described herein also enables the selective injection of harmonics at predetermined harmonic orders to modulate the acoustic behavior of the electric drive system. In particular, the teachings employ bandwidth partitioning of the harmonic regulator in the current or flux domain to provide a configurable control topology, i.e., a control topology that can be tuned to resolve one or more higher-order harmonics at a given torque-speed operating point, as described herein.

[0005] Motor control systems typically offer relatively weak attenuation of higher harmonics and associated torque disturbances, and generally operate at low machine speeds. For example, a typical electric drive control solution might employ a combination of a synchronization filter and a proportional-integral / PI regulator operating in a low bandwidth to perform harmonic current regulation without acknowledging changes in machine parameters within the harmonic reference frame. Furthermore, this approach attempts to eliminate unwanted torque ripples through the transmission of harmonic current commands, rather than interpreting changes in the harmonic reference frame of the flux as a function of the output torque.

[0006] Conversely, the solution described in detail herein aims to operate at much higher machine rotation speeds using the aforementioned bandwidth-partitioning harmonic regulator. As used herein, the term "bandwidth partitioning" refers to the purposeful allocation of available bandwidth across multiple different harmonic orders (e.g., the 3rd, 6th, and / or 12th harmonics in the exemplary application). Within the scope of this disclosure, this bandwidth partitioning control strategy enables combinations of controllers with different bandwidth and frequency process variations to achieve higher bandwidth and provides greater noise immunity compared to existing methods. The bandwidth partitioning implemented in this disclosure results in operation without phase hysteresis, even without DC component errors.

[0007] This paper recognizes that spatial harmonics tend to cause fluctuations in the flux components along the direct axis (d-axis) and quadrature axis (q-axis) of a rotating electrical machine. The dominant fluctuation frequencies typically include the 6th harmonic, although this is not always the case. Therefore, this method enables application-specific tuning of harmonic and acoustic performance to reduce and / or eliminate the effects of the 6th harmonic and / or other target problematic harmonic orders, with the disclosed bandwidth allocation method facilitating this harmonic performance tunability.

[0008] In various embodiments, the configurable control device of the present invention operates as a function of the total output torque and rotational / angular velocity of the motor. In this example, the motor is a high-voltage electric traction motor, where possible variations in the injected phase angle based on the operating point take into account variations in the magnetic flux as a function of the load torque in a harmonic reference frame. Furthermore, this method can be used to shape the d-axis and q-axis current commands to closely follow the real-time changing torque curves, rather than the constant maximum torque per ampere (MTPA) curves of conventional approaches.

[0009] This document discloses a method for controlling the operation of a rotating electric motor. A specific embodiment of this method includes receiving commanded torque and rotational speed of the motor via a harmonic compensation regulator (HCR) logic block of an onboard electronic control unit / controller. The method includes calculating dq harmonic compensation current and dq harmonic compensation voltage via the HCR logic block in response to a set of enable conditions. This is accomplished using the commanded torque and rotational speed for a predetermined harmonic order, wherein the harmonic compensation current and voltage are configured to eliminate torque and current fluctuations in the predetermined harmonic order.

[0010] The method further includes adding the dq harmonic compensation current and dq harmonic compensation voltage to the dq current command and dq voltage command, respectively, to generate regulated dq current commands and regulated dq voltage commands. The method then includes using the regulated dq current commands and regulated dq voltage commands to control the operation of the motor.

[0011] The HCR logic block can sum the dq harmonic compensation current and the dq harmonic compensation voltage of each harmonic order to generate harmonic compensation current and harmonic compensation voltage respectively.

[0012] The method may further include generating a dq current command via the torque-to-current logic block of the controller based on the commanded torque, rotational speed, and DC bus voltage level.

[0013] The torque-to-current logic block can optionally be implemented as a lookup table indexed or referenced by the commanded torque, rotational speed, and DC bus voltage level.

[0014] In some embodiments, the motor is connected to a traction power inverter module (TPIM), in which case the method includes: subtracting the actual dq current of the motor from a regulated dq current command to obtain a dq current error value; using the dq current error value to generate a regulated dq voltage command via an HCR logic block; and converting the regulated dq voltage command into a phase current command. The method then includes providing the phase current command to the TPIM to excite the motor.

[0015] The HCR logic block conceived herein may include a feedforward harmonic compensation generator (FFHC-GEN) logic block and a harmonic compensation regulator (HC-REG) logic block. A method in such an embodiment may include: determining and outputting a dq harmonic compensation current via the HC-REG logic block, determining and outputting a dq harmonic compensation voltage via the HC-REG logic block, and scaling the dq harmonic compensation current via a scaling block of the FFHC-GEN logic block.

[0016] In this configuration, the FF HC-GEN logic block may include a current amplitude lookup table configured to provide separate d-axis and q-axis harmonic compensation currents, and a phase injection lookup table configured to provide harmonic compensation phase adjustment. The FF HC-GEN logic block may also include a null block, wherein the method includes selectively zeroing the separate d-axis and q-axis harmonic compensation currents via a zero block / null block according to the commanded torque and rotational speed.

[0017] As part of this method, the HC-REG logic block may include multiple separate control loops for each corresponding harmonic order, wherein each loop has selectable proportional and integral gain blocks and a frequency correction block. Determining and outputting the dq harmonic compensation voltage via the HC-REG logic block may include: calculating the corresponding harmonic-specific dq harmonic compensation voltage for each harmonic order, and summing the corresponding harmonic-specific dq harmonic compensation voltages together to generate the dq harmonic compensation voltage.

[0018] Some embodiments of this method may include using HCR logic blocks to inject audible tones at predetermined harmonic orders.

[0019] The HCR logic block can optionally operate in the magnetic flux domain. In such an embodiment, the method may include: converting the dq harmonic compensation current from the FF HC-GEN logic block into a dq harmonic compensation flux, and calculating a dq harmonic compensation flux error value. Additional actions taken as part of this method may include: sending the dq harmonic compensation flux error value to the HF-REG logic block, and using the dq harmonic compensation flux error value to determine and output the dq harmonic compensation voltage via the HC-REG logic block.

[0020] This document also discloses an electric drive system. In a possible configuration, the electric drive system includes a battery pack, a rotary motor coupled to a load, a TPIM connected to the battery pack and the rotary motor, and a controller communicating with the TPIM. The controller is configured to perform the methods outlined above.

[0021] The present invention also includes the following solutions:

[0022] Option 1. A method for controlling the operation of a rotating electric machine, the method comprising:

[0023] The controller receives the motor's command torque and rotational speed via a bandwidth-divided harmonic compensation regulator (HCR).

[0024] In response to a set of enable conditions, the HCR calculates dq harmonic compensation current and dq harmonic compensation voltage for one or more predetermined harmonic orders using the commanded torque and the rotational speed, wherein the harmonic compensation current and harmonic compensation voltage are configured to selectively eliminate torque and current fluctuations in the one or more predetermined harmonic orders.

[0025] The dq harmonic compensation current and the dq harmonic compensation voltage are respectively applied to the dq current command and the dq voltage command to generate an adjusted dq current command and an adjusted dq voltage command; and

[0026] The operation of the motor is controlled using the regulated dq current command and the regulated dq voltage command, including eliminating one or more of the torque ripples and current ripples in one or more predetermined harmonic orders.

[0027] Option 2. According to the method of Option 1, wherein the one or more predetermined harmonic orders include a plurality of harmonic orders, and wherein the HCR is configured to add together the dq harmonic compensation current and the dq harmonic compensation voltage for each of the plurality of harmonic orders, thereby generating the harmonic compensation current and the harmonic compensation voltage.

[0028] Option 3. The method according to Option 1, wherein the motor is connected to a DC voltage bus having a DC bus voltage level, the method further comprising using the torque-to-current logic block of the controller to generate the dq current command based on the command torque, the rotational speed and the DC bus voltage level.

[0029] Option 4. According to the method of Option 3, wherein the torque-to-current logic block is a lookup table indexed or referenced by the command torque, the rotational speed and the DC bus voltage level.

[0030] Option 5. The method according to Option 1, wherein the motor is connected to a traction power inverter module (TPIM), the method further comprising:

[0031] The actual dq current of the motor is subtracted from the adjusted dq current command to obtain the dq current error value;

[0032] The adjusted dq voltage command is generated via the HCR logic block using the dq current error value.

[0033] Convert the regulated dq voltage command into a phase current command; and

[0034] The phase current command is provided to the TPIM to excite the motor.

[0035] Solution 6. The method according to Solution 1, wherein the HCR includes a feedforward harmonic current generation logic block (FFHC-GEN) logic block and a harmonic current regulator (HC-REG) logic block, the method comprising:

[0036] The dq harmonic compensation current is determined and output via the HC-REG logic block; and

[0037] The dq harmonic compensation voltage is determined and output via the HC-REG logic block; and

[0038] The scaling block of the FF HC-GEN logic block causes the dq harmonic compensation current to be skewed.

[0039] Option 7. According to the method of Option 6, wherein the FF HC-GEN logic block includes a current amplitude lookup table configured to provide separate d-axis and q-axis harmonic compensation currents, and a phase injection lookup table configured to output harmonic compensation phase adjustment.

[0040] Option 8. The method according to Option 7, wherein the FF HC-GEN logic block includes an empty block or a zero block, the method comprising selectively invalidating or zeroing separate d-axis and q-axis harmonic compensation currents via the empty block or zero block according to the command torque and the rotational speed.

[0041] Option 9. The method according to Option 6, wherein the HC-REG logic block includes a plurality of separate control loops for each corresponding harmonic order, each loop having selectable proportional and integral gain blocks and frequency correction blocks, wherein determining and outputting the dq harmonic compensation voltage via the HC-REG logic block includes: calculating a corresponding harmonic-specific dq harmonic compensation voltage for each of the harmonic orders, and adding the corresponding harmonic-specific dq harmonic compensation voltages together to thereby generate the dq harmonic compensation voltage.

[0042] Option 10. The method according to Option 6, wherein the HCR operates in the flux domain, the method further comprising:

[0043] The dq harmonic compensation current from the FF HC-GEN logic block is converted into dq harmonic compensation flux.

[0044] Calculate the dq harmonic compensation flux error value;

[0045] Send the dq harmonic compensation flux error value to the HF-REG logic block; and

[0046] The dq harmonic compensation flux error value is used to determine and output the dq harmonic compensation voltage via the HC-REG logic block.

[0047] Option 11. The method according to Option 1 further includes using the HCR to selectively inject audible tones at predetermined harmonic orders.

[0048] Option 12. An electric drive system, comprising:

[0049] Battery pack;

[0050] A rotating electric motor connected to a load;

[0051] A traction power inverter module (TPIM) connected to the battery pack and the rotating motor; and

[0052] The controller communicates with the TPIM and is configured to:

[0053] The controller receives the command torque and rotational speed of the motor via a bandwidth-divided harmonic compensation regulator (HCR).

[0054] In response to a set of enable conditions, the HCR calculates dq harmonic compensation current and dq harmonic compensation voltage for one or more predetermined harmonic orders using the commanded torque and the rotational speed, wherein the harmonic compensation current and harmonic compensation voltage are configured to eliminate torque and current fluctuations in the one or more predetermined harmonic orders.

[0055] The dq harmonic compensation current and dq harmonic compensation voltage are respectively applied to the dq current command and dq voltage command to generate regulated dq current command and regulated dq voltage command; and

[0056] The operation of the motor is controlled using the regulated dq current command and the regulated dq voltage command.

[0057] Option 13. The electric drive system according to Option 12, wherein the one or more predetermined harmonic orders include a plurality of harmonic orders, and wherein the HCR logic block is configured to add together the dq harmonic compensation current for each of the plurality of harmonic orders and the dq harmonic compensation voltage for each of the plurality of harmonic orders, thereby generating the harmonic compensation current and the harmonic compensation voltage, respectively.

[0058] Option 14. The electric drive system according to Option 12, wherein the controller is configured to use the HCR logic block to selectively inject audible tones at predetermined harmonic orders.

[0059] Option 15. The electric drive system according to Option 12, wherein the controller is further configured to:

[0060] The actual dq current of the motor is subtracted from the adjusted dq current command to obtain the dq current error value;

[0061] The adjusted dq voltage command is generated via the HCR logic block using the dq current error value.

[0062] The adjusted dq voltage command is converted into a phase current command; and

[0063] The phase current command is provided to the TPIM to excite the motor.

[0064] Option 16. The electric drive system according to Option 12, wherein the HCR includes a feedforward harmonic current generation logic block (FF HC-GEN) logic block and a harmonic current regulator (HC-REG) logic block, and the controller is further configured to:

[0065] The dq harmonic compensation current is determined and output via the HC-REG logic block; and

[0066] The dq harmonic compensation voltage is determined and output via the HC-REG logic block; and

[0067] The scaling block of the FF HC-GEN logic block causes the dq harmonic compensation current to be skewed.

[0068] Option 17. The electric drive system according to Option 16, wherein the FF HC-GEN logic block includes lookup tables configured to provide separate d-axis and q-axis harmonic compensation currents, and a phase injection lookup table configured to provide harmonic compensation phase adjustment.

[0069] Option 18. The electric drive system according to Option 17, wherein the FF HC-GEN logic block includes an empty block or a zero block, and the controller is further configured to selectively invalidate or zero individual d-axis and q-axis harmonic compensation currents via the empty block or zero block according to the commanded torque and the rotational speed.

[0070] Option 19. The electric drive system according to Option 17, wherein the HC-REG logic block includes a plurality of separate control loops for each corresponding harmonic order, each loop having selectable proportional and integral gain blocks and a frequency correction block, wherein the controller is configured to determine and output the dq harmonic compensation voltage via the HC-REG logic block as follows: calculating a corresponding harmonic-specific dq harmonic compensation voltage for each of the harmonic orders, and then adding the corresponding harmonic-specific dq harmonic compensation voltages together to generate the dq harmonic compensation voltage.

[0071] Option 20. The electric drive system according to Option 17, wherein the HCR operates in the flux domain, and the controller is further configured to:

[0072] The dq harmonic compensation current from the FF HC-GEN logic block is converted into dq harmonic compensation flux.

[0073] Calculate the dq harmonic compensation flux error value;

[0074] Send the dq harmonic compensation flux error value to the HF-REG logic block; and

[0075] The dq harmonic compensation flux error value is used to determine and output the dq harmonic compensation voltage via the HC-REG logic block.

[0076] The foregoing features and advantages, as well as other features and advantages, of this disclosure will be apparent from the following detailed description of the embodiments and preferred modes for carrying out the described disclosure, taken in conjunction with the accompanying drawings and claims. Attached Figure Description

[0077] Figure 1 This is a schematic diagram of an exemplary motor vehicle having an electric drive system and a controller configured to perform the methods described herein.

[0078] Figure 2 This is a schematic control logic diagram describing an embodiment for implementing the method.

[0079] Figure 3 and Figure 4 The logic blocks for generating feedforward harmonic current and bandwidth-divided harmonic current regulators are described separately. Both logic blocks can be used as... Figure 2 This is a part of the control logic shown.

[0080] Figure 5 and Figure 6 It is a graph of magnetic flux (vertical axis) versus electrical angle (horizontal axis), illustrating aspects of this disclosure that provide for the operating point variation of the injection phase angle.

[0081] Figure 7 yes Figure 2 An alternative embodiment of the implementation is provided, wherein the harmonic components are controlled in the flux domain and the fundamental components are controlled in the current domain.

[0082] Figure 8 yes Figure 7 An alternative embodiment of the implementation, wherein the harmonic and fundamental components are controlled in the flux domain.

[0083] Figure 9 Is it possible to... Figure 8 The alternative bandwidth partitioning harmonic current regulator logic block is used in conjunction with the configuration.

[0084] Figure 10 and Figure 11 This is a representative embodiment of a flux-current lookup table that can be used as part of this method.

[0085] Figure 12 and Figure 13 These are representative curves showing the reduction in vibration and noise relative to the baseline level. Detailed Implementation

[0086] This disclosure allows for many different forms of embodiments. Representative examples of this disclosure are shown in the accompanying drawings and are described in detail herein as non-limiting examples of the disclosed principles. Therefore, elements and limitations described in the abstract, background, summary, description of drawings, and detailed description sections but not expressly set forth in the claims should not be incorporated into the claims, individually or collectively, by implication, inference, or otherwise.

[0087] For the purposes of this specification, unless specifically waived, the singular includes the plural, and vice versa; the words “and” and “or” shall be both connective and disjoint; the words “any” and “all” shall mean “any and all”; and the words “including,” “contains,” “covers,” “has,” and their substitutions shall mean “includes without limitation.” Furthermore, approximate terms, such as “approximately,” “almost,” “substantially,” “roughly,” “approximately,” etc., may be used herein in the sense of, for example, “in, near, or almost in,” or “within 0-5%,” or “within acceptable manufacturing tolerances,” or any logical combination thereof.

[0088] Referring to the accompanying drawings, the same reference numerals denote the same parts. Figure 1 A motor vehicle 10 having an electric drive system 11 configured as described herein is schematically illustrated. The electric drive system 11 includes a rotary motor (M... E ) 14, its operation is achieved via control signals from the onboard controller (C) 50 (arrow CC) OReal-time adjustment and control. Used for implementation of the following reference. Figure 2-13 The instructions 100 of the control logic 50L, 150L or 250L described herein are recorded in the memory (M) of the controller 50 and executed by one or more processors (P) to provide the benefits described herein.

[0089] By way of example, and not limitation, these benefits include smoothing output torque generation and attenuating noise during ongoing operation of the electric drive system 11. The controller 50 achieves these objectives through harmonic modulator bandwidth division as described below, with targeted elimination of multiple predetermined torque and current fluctuation harmonic orders and targeted variation of the injected phase angle. Other advantages of this bandwidth division control scheme include the ability to selectively inject predetermined acoustic tones with specific harmonic orders. For example, in Figure 1 In the motor vehicle 10, audible sounds of lower harmonic orders (e.g., the first or third harmonic order) may be introduced so that acoustic and / or mechanical sounds emanating from another possibly higher harmonic (e.g., the sixth or twelfth harmonic order) can acoustically distract the operator of the motor vehicle 10; and / or supplement another harmonic order generated during the torque-generating operation of the motor 14.

[0090] Figure 1 The controller 50 can be implemented in response to an input signal (arrow CC). IN The controller 50 comprises one or more electronic control units or computing nodes. The controller 50 includes a dedicated amount of memory (M) and one or more processors (P), such as microprocessors or central processing units, as well as other associated hardware and software, such as digital clocks or timers, input / output circuits, buffer circuits, etc. The memory (M) may include a sufficient amount of read-only memory, such as magnetic or optical memory. For simplicity, the term "controller" as used herein may include one or more electronic control modules, units, processors, and their associated hardware components, including... Figure 2-4 The logic 50L, 150L, ​​or 250L shown in 7 and 8, application-specific integrated circuits (ASICs), system-on-a-chip (SoCs), electronic circuits, and other hardware required to provide programming functionality.

[0091] Further information Figure 1 The electric drive system 11 shown illustrates an exemplary embodiment of the motor 14, wherein the stator 14S is coaxially arranged with respect to the rotor 14R in a radial flux configuration. The stator 14S thus surrounds the rotor 14R. However, other embodiments of the motor 14, including axial flux type motors, can be used within the scope of this disclosure. Figure 1 The simplified representative embodiment of motor 14 shows only one possible configuration.

[0092] exist Figure 1In a representative embodiment, motor 14 is a multiphase / AC traction motor used to generate total output torque (arrow T). O The torque is transmitted to the output member 17, which is connected to the rotor 14R. In the exemplary motor vehicle 10, the output member 17 is connected to one or more wheels 15 via one or more drive shafts 19, and outputs torque (arrow T). O The motor 14 drives the rotation of the wheels 15 to propel the vehicle 10. Other possible arrangements may involve placing the motor 14 directly on or close to one or more individual wheels 15, and / or the motor 14 may sometimes be used as a generator to power other components on the vehicle 10. Figure 1 The configuration shown is an example of this teaching and not a limitation.

[0093] When motor 14 is configured as a typical multiphase / AC device in automotive propulsion applications, the excitation of the corresponding excitation windings (not shown) of stator 14S requires input power from the on-board power supply. For this purpose, electric drive system 11 may include a high-voltage battery pack (B... HV 16, for example, a multi-cell rechargeable lithium-ion configuration or other suitable battery chemistry. While the term “high voltage” is relative to the typical 12-15V auxiliary / low voltage level, and therefore “high voltage” may need to exceed its voltage level, exemplary hybrid electric vehicle (HEV) or all-battery electric vehicle (BEV) propulsion applications of the type envisioned herein may require battery pack 16 to have a voltage capability of, for example, 300V or higher.

[0094] Battery pack 16 is electrically connected to traction power converter module (TPIM) 20 via a high-voltage DC voltage bus (VDC), and TPIM 20 is in turn electrically connected to stator 14S via a high-voltage AC voltage bus (VAC). Although omitted for simplicity, TPIM 20 is internally configured and externally controlled via the ON / OFF state control of multiple dies of semiconductor switches, typically implemented as IGBTs or MOSFETs. Thus, by switching the operation of TPIM 20 to an AC output voltage, the DC input voltage of TPIM 20 is inverted to power motor 14 in its ability as a propulsion or traction motor. During recharge events, TPIM 20 can operate in the reverse manner, i.e., converting the AC input voltage to a DC output voltage to recharge the constituent battery cells of battery pack 16.

[0095] Other components may be connected to the electric drive system 11, such as, but not limited to, the DC-DC converter 18 shown and the auxiliary battery (B). AUX160. As described above, the auxiliary voltage level is typically 12-15V, therefore the DC-DC converter 18 can be operated by internal switching and signal filtering, as understood in the art, to receive a relatively high DC voltage from the DC voltage bus (VDC) and output a lower auxiliary voltage (V) to the auxiliary battery 160. AUX Therefore, the motor 14 is only one of several devices that require a reliable and continuous supply of electrical energy from the battery pack 16 during the ongoing propulsion operation of the motor vehicle 10.

[0096] refer to Figure 2 , Figure 1 The controller 50 shown can be programmed with control logic 50L, which is adapted to solve problems when operating the electric drive system 11, especially in Figure 1 The propulsion torque of the rotating motor 14 generates various undesirable torque fluctuations during operation, resulting in NVH effects caused by torque fluctuations and current fluctuations. For simplicity, line AA separates the physical system (arrow A) from the discrete control system (arrow B) implemented by exemplary control logic 50L. The physical system (arrow A) includes TPIM 20, motor 14, and rotary position sensor (S) 21, such as an encoder or resolver, which is positioned relative to the rotor 14R ( Figure 1 ) Connect or position to measure and output rotor 14R ( Figure 1 Rotation / angular position (arrow θ) e As those skilled in the art will understand. Similarly, Figure 2 The remaining diagrams use a superscript "*" to indicate command signals. The absence of such an asterisk indicates a measured, calculated, or estimated state value that is not necessarily used as a command value in the context of control logic 50L.

[0097] Figure 2 The various input signals of the constituent logic blocks of the control logic 50L described herein are included. Figure 1 The input signal is shown in simplified form (arrow CC). IN As those skilled in the art will understand, a control system for an electric traction motor (e.g., exemplary rotary motor 14) receives: the measured, calculated, or estimated angular / rotational speed (ω) of motor 14. e The commanded torque (arrow) ), for example, obtained by controller 50 or another control module in response to driver input (e.g., accelerator pedal request); and DC bus voltage (V dc The size of ), that is, Figure 1 The current measured or reported voltage level of the DC voltage bus (VDC) is schematically shown. The rotational speed (ω) of motor 14... eThe measured angular position (θ) can be obtained from the position sensor 21. e The signal is obtained in real time; for clarity, two signals are shown.

[0098] Control logic 50L torque to current Logic block 30 receives the input and then outputs the instructed direct-axis (d-axis) and quadrature-axis (q-axis) current commands to the summing node N1. For simplicity, the current commands are... Figure 2 Chinese and Israeli vector symbols This indicates that downstream of logic block 30, the synchronous current regulator (I-Sync Reg) logic block 34 receives the aforementioned rotational speed (ω) of motor 14. e The input is in the form of ) and I from the subtraction node N2. dq Error signal (arrow I) dq，Err The source and use of the error signal will be described below. In response, logic block 34 outputs d-axis and q-axis (dq) voltage commands. Figure 2 Chinese abbreviation The output is summed via node N3 and the harmonic compensation voltage component from logic block 36 of the harmonic compensation regulator (HC-REG). The summation is also described in detail below. The output of the summing node N3 is the regulated dq voltage command ( ), which is then fed to reference frame transition logic block 38 (“ ”).

[0099] like" As shown by the symbol, Figure 1 The controller 50 uses reference frame switching logic block 38 to convert the regulated dq voltage command ( The logic block 38 converts the voltage commands of phases a, b, and c to a multiphase reference frame relevant to the specific configuration of motor 14. These phases in a typical three-phase embodiment of motor 14 are nominally referred to in the art as phases a, b, and c, and for consistency, this convention is adopted herein. Therefore, logic block 38 converts the voltage commands of phases a, b, and c into phases a, b, and c. The output is sent to the pulse width modulation generator (“PWM GEN”) logic block 40. In response, logic block 40 generates an appropriate ON / OFF control signal to change the corresponding ON / OFF switching state of the resident semiconductor switch (not shown) housed within TPIM 20. TPIM 20 then transmits a phase-specific electric drive current / voltage to the stator 14S of the rotating motor 14. Figure 1 For clarity and simplicity, the currents in phases a, b, and c are... Figure 2 The abbreviation for I is abc .

[0100] Still referencing Figure 2 The exemplary control logic 50L, the previously mentioned measured angular position (θ) e Then it is sent as an electrical signal to another reference frame conversion block 42 (“ "), which inverts the reference frame transformation function previously performed by logic block 38, that is, it transforms the individual phase currents I abc Converted into corresponding d-axis and q-axis currents (I dq Then, at node N2, the d-axis and q-axis currents (I) are... dq Subtract from each other to get I. dq Error signal (I) dq, err ).

[0101] Bandwidth division and harmonic compensation: Figure 2 The control logic 50L of this disclosure is used for prior art control of electric traction motors (e.g., motor 14 shown in the figure) and is therefore well known in the art. These functions include performing basic dq and abc reference frame transformations, using error signals as a PI control architecture, and feedback control techniques in PWM or other high-speed switching control principles for controlling the ON / OFF conduction states of semiconductor switches. For these functions, the control logic 50L of this disclosure adds a bandwidth-divided harmonic compensation regulator 31, wherein the harmonic compensation regulator 31 is configured as described below to reduce... Figure 1 Undesired fluctuations within the electric drive system 11 cause vibration and acoustic noise.

[0102] The bandwidth-division harmonic compensation regulator 31 described in this paper includes two main functional components: (1) a feedforward harmonic current generation logic block 32 (“FF HC-GEN”), and (2) the harmonic current regulator logic block 36 briefly mentioned above. The logic blocks 32 and 36 respectively generate the harmonic compensation current component (I0). dq * Hx ) and output it to the summing node N1 and generate the harmonic compensation voltage component (V dq * Hx ) and output it to the summing node N3, where each component (I dq * Hx and V dq * Hx Together, they eliminated multiple target harmonic orders of current and torque fluctuations, as described below.

[0103] Regarding the feedforward harmonic current generation logic block 32, the inputs of logic block 32 include the torque (arrow) of the aforementioned command from motor 14. ) and rotational speed (ω) e Regarding the specific configuration of motor 14, Figure 1 The controller 50 can be programmed to have torque (arrow) controlled by instructions. ) and rotational speed (ω) e A set of lookup tables indexed or referenced by a value. Therefore, the harmonic compensation current component (I) applied in a given situation... dq * Hx The operation point-specific value can be extracted from such a lookup table and fed to the summing node N1, or, in other implementations, such a value can be calculated in real time.

[0104] Similarly, the harmonic current regulator logic block 36 receives the rotational speed (ω) of the motor 14. e And using another lookup table or calculation, the harmonic compensation voltage component (V) is... dq * Hx The output is sent to the summing node N3. The operation of the harmonic compensation regulator 31 and its constituent logic blocks 32 and 34 can be selectively enabled by the enable logic block 39 (“ENBL”), whose inputs include the command torque (arrow). ), rotational speed (ω) e The output of ENBL includes a DC voltage (Vdc) and an enable signal (arrow CC). ENBL In other words, this teaching allows for highly configurable activation of control characteristics based on torque and speed, with an eye toward the available DC bus voltage. As explained in further detail below, calibration of the overall or fundamental equations for the lookup table used to implement the harmonic compensation regulator 31 requires accurate object characterization and NVH analysis of the electric drive system 11 to determine and fine-tune the harmonic compensation current and voltage components I, respectively. dq * Hx and V dq * Hx The amplitude is adjusted to effectively eliminate torque and current fluctuations of multiple harmonic orders.

[0105] Now for reference Figure 3 For any number (n) of different harmonic orders, it describes Figure 2 This is an exemplary implementation of the aforementioned feedforward harmonic current generation logic block 32. When confirming the enable condition for a given harmonic order, for example, nominally referred to as Hx1, as shown, the harmonic component is multiplied at node N6 by the value from... Figure 1 The position sensor 21 receives the angular position ( ).

[0106] The representative topology shown for logic block 32 thus allows for (n) specific harmonics, i.e., Hx1, ..., Hxn, each of which can be individually isolated and processed by controller 50 to fine-tune torque and current ripple elimination performance, and provides other benefits as described below. For example, in some embodiments, Figure 3 The harmonic order marked Hx1 can be the 6th harmonic, the 12th harmonic, or another target harmonic order. Therefore, logic block 32 can be divided into multiple sub-blocks 32-A, ..., 32-n. Since each harmonic component can be processed in a similar manner, sub-blocks 32-A and 32-n are schematically identical except for the "-n" symbol, as will be understood by those skilled in the art. Therefore, the description of sub-block 32-A applies to sub-block 32-n, and for simplicity and brevity, a separate description of sub-block 32-n is omitted.

[0107] Figure 3 Subblock 32-A can be selectively enabled by enable logic block 39, which can be enabled by... Figure 1 The actual or estimated output torque (Te1, Te2, Te3, Te4) of motor 14 and / or the actual or estimated rotational speed (ω) e1 ,ω e2 , ω e3 , ω e4 Notification. The upward arrow in logic block 39 indicates enable (ENBL), and the downward arrow indicates disable (DSBL) of the computational function in sub-block 32-A. Similar enable logic 39-n can be used... Figure 2 The control logic 50L processes each additional harmonic component. The output torque T e1 and T e2 Forming mutual opposition, output torque T e3 and T e4 That's also true.

[0108] Therefore, possible embodiments of enabling logic block 39 may require the rated torque Te2 and / or rated speed ω. e2 Sub-block 32-A is enabled, but only until the torque / speed drops to the level determined by torque Te1 and speed ω. e1 Sub-block 32-A is only deactivated when the indicated value is below the lower value. This applies to higher torques Te3 and Te4, and the corresponding speed ω. e3 and ω e4 The same situation can also occur, enabling harmonic processing and feedforward adjustment of sub-block 32-A for specific torques or speeds where harmonic-induced NVH is particularly problematic.

[0109] for Figure 3 Sub-block 32-A, scaling block 60 receives rotation speed (ω) eThe input is taken as input, and its output is then smoothly scaled to prevent sudden changes in torque. As will be understood, a motor control response to rapid fluctuations in the control input tends to cause voltage spikes, where user-perceived drivetrain vibrations are a potential effect. Therefore, scaling block 60 can output a harmonic scaling factor (arrow H) with a unitless value between 0 and 1. x1 S), where the ramp rate is calibrated based on the desired response.

[0110] The implementation of sub-block 32-A also requires the use of lookup tables (LUTs) 61, 62, and 63, where each of the lookup tables 61, 62, and 63 is determined by the rotational speed ( ) and command torque (arrow) Index. Look up Table 61 to output d-axis and q-axis harmonic compensation components based on torque and speed (arrows I and I are respectively). dHx1,mag and I qHx1,mag These values ​​are multiplied at their respective nodes N4 and N5 (e.g., ... Figure 3 (As shown by "X") with harmonic scaling factor (arrow H) x1 S) Scaling. Similarly, lookup table 62 outputs the phase injection component ϕ for the harmonic component being processed. Hx1 For example, the 6th harmonic order, which outputs (H) from node N6 at node N7. x1 The signal is subtracted to produce the phase error signal (arrow ϕ). err In this way, lookup table 62 effectively injects specific acoustic tones, thereby resulting in reduced acoustic noise in the electric drive system 11.

[0111] Then, sub-block 32-A calculates the phase error signal (arrow ϕ). err The sine (SIN) and cosine (COS) values ​​are then fed to nodes N8 and N9, respectively. The output of node N8 is the d-axis current component required to correct the harmonic component Hx1, i.e., arrow I. dHx1 Similarly, node N9 provides the q-axis current component required to correct the harmonic component Hx1, i.e., arrow I. qHx1 If needed, the logic flow of subblock 32-A can be executed on the additional harmonic order, which will generate the additional d-axis and q-axis current components required to correct the additional harmonic component Hxn.

[0112] The summation nodes N10 and N11 shown within logic block 32-n can be used to sum the various d-axis and q-axis current components, and then feed the sum to a scalar-to-vector (" ) Calculate logic block 64, which then outputs Figure 2 The above-mentioned harmonic compensation current component (I) is shown. * dqHxLookup table 63 (“0-Hx1 Command”) serves as a null / zero block by selectively deactivating or zeroing the individual d-axis and q-axis harmonic compensation currents based on the torque and rotational speed of the command. Block 63 can be used to prevent the rotational speed (ω) from being reduced to zero. e ) and motor torque (T) e At a specific combination of points, the corresponding harmonics are corrected as a function of rotational speed and motor torque, i.e., by outputting empty / zero values ​​to nodes N8 and N9.

[0113] Therefore, the exemplary configuration of sub-blocks 32-A to 32-n enables the operating point variation of the phase angle based on torque and speed to eliminate torque ripples. The illustrated logic flow and circuit topology provide the ability to eliminate torque and current ripples of multiple orders, where each harmonic has a corresponding sub-block 32-N as shown, for tunability and precise calibration of the motor 14 in a given embodiment.

[0114] Turn now Figure 4 , Figure 2 The harmonic current regulator logic block 36 can be implemented as shown and used in conjunction with the synchronous current regulator block 34. The topology shown allows the harmonic proportional gain and integral gain K to be set at blocks 44 and 46. pdq,Hx1 and K idq,Hx1 Furthermore, it also allows for the aforementioned bandwidth partitioning, namely, dividing logic block 36 into separate control loops for the corresponding harmonic bandwidths while maintaining the synchronous current regulator bandwidth.

[0115] exist Figure 4 Inside, node N3 will adjust the dq voltage command ( ) as the dq voltage instruction from logic block 34 ( ) and harmonic compensation voltage components (V) from logic block 36 dq * Hx The sum of the outputs, the values ​​of the harmonic compensation voltage components can be limited within the calibration range by limiting block 56 (“Lim”) (e.g., a bandpass filter). Harmonic current regulator logic block 36 thus enables bandwidth partitioning to provide the ability to individually regulate or process multiple harmonic orders.

[0116] Compared to existing methods that provide weak attenuation of higher-order interference, Figure 4 The control logic topology has higher bandwidth and correspondingly improved interference suppression. For example, when motor 14 is operated at a higher speed, it can experience higher-order NVH effects, where... Figure 4 The solution shown is the same as Figure 3 The feedforward harmonic current generation logic block 32 is used in conjunction with the various NVH-related improvements disclosed herein.

[0117] In the described embodiments, from Figure 2 The above error signal (I) of node N2 dq , Err ) is fed to logic block 34, and for those to be fed by Figure 1 The controller 50 processes each of the (n) different harmonic components, feeding them into three processing blocks 44, 46, and 48 in a group. Therefore, Figure 4 The diagram shows a time-domain parameter block 52 (i.e., with a sampling frequency Ts) using calibration and a block 54 (z) with an integrator. -1 Discrete PI control settings. Blocks 44 and 56 apply the predetermined proportional or integral gain described above to the harmonic component being processed, nominally Hx1 (e.g., the 6th or 12th harmonic order in a typical embodiment).

[0118] Theory and Support: In the process Figure 5-13 Before proceeding with the discussion, some mathematical / theoretical support for the control principles of this solution is provided. As will be understood, the time-varying voltage equations in the typical dq reference frame for the motor are expressed as follows:

[0119]

[0120] in and These are the d-axis and q-axis currents in amperes (A). and R is the d-axis and q-axis voltage in volts (V), and R is the stator winding resistance in ohms. and Here, the flux linkages along the d and q axes are expressed in units of Wb. Time-varying flux linkages can be written as...

[0121]

[0122] in It is the d-axis flux linkage caused by stator excitation. It is the d-axis flux linkage caused by the magnetic flux of the permanent magnet or the rotor flux, and It is the d-axis flux linkage caused by stator excitation, and It is the q-axis flux linkage caused by permanent magnet flux or rotor flux.

[0123] If we assume that the d-axis is related to the magnetic flux linkage of the permanent magnet Aligning them, equations (3) and (4) above can be written as:

[0124]

[0125] Therefore, when Figure 1 As rotor 14R rotates, time-varying flux , It is the d-axis and q-axis current I d and I q Motor temperature T and angular position This function captures saturation and cross-coupling effects, as well as spatial harmonic effects.

[0126] Derived terms can be expanded as follows:

[0127]

[0128] in It is the d-axis incremental inductance in units of (H). They are mutually q-axis self-incrementing inductors, and and This is the incremental inductance between the d-axis and q-axis, illustrating the cross-coupling nature. The incremental inductance is given as the slope of the tangent between the flux linkage and the current. When designing... Figure 1 These variables are necessary when using controller 50 because they are responsible for transient response.

[0129] In contrast to incremental inductance, apparent inductance is defined as the slope of the linearized relationship between flux linkage and current, which can be defined as:

[0130]

[0131] item and It can be represented by the apparent inductance term as part of the process used to linearize the plant.

[0132]

[0133] From here, and Implicit as Unless otherwise stated.

[0134] Using the relations derived from equations (9)-(14) above, and by applying these relations to equations (1) and (2), taking into account spatial harmonics, cross-coupling, and saturation effects, the voltage equations can be extended as follows to describe Figure 1 The object of motor 14:

[0135]

[0136] The spatial harmonics considered in this paper are flux fluctuations or pulsations, which can be further decomposed into fundamental components and harmonics, where the dominant frequency is usually the 6th or 12th (Hxn) order, but can vary depending on the motor configuration.

[0137]

[0138] An example of a flux diagram is in Figure 10 and 11 The diagram is shown, where the outlines represent the changes in the values ​​shown, and typically represent the magnetic flux as the d-axis and q-axis currents (i.e., Id and Iq, respectively). d and I q The effect of temperature T can be compensated for additionally.

[0139] Examples of terms are represented as electrical angles. The function, where Hxn = 6, implying the 6th harmonic under different torques, implying different Current. This can replace lookup tables to additionally compensate for the effects of temperature variations. Similarly, the incremental inductance, mutual inductance, and apparent inductance discussed so far can be decomposed into fundamental and harmonic components. Below is a generalized representation of all the inductances discussed so far:

[0140]

[0141] The fundamental component of the apparent and incremental inductance terms discussed so far can be used Figure 10 and 11 The type of triaxial surface flux map shown is used to obtain the corresponding d-axis flux (λ). d ) and q-axis flux (λ) q The components are used as d-axis and q-axis currents (I) d and I q The flux variation of the apparent and incremental inductance is a function of Hxnθ. The harmonic components of the apparent and incremental inductance can be obtained using the relationship between magnetic flux and current, relative to Hxnθ. e Changes in Figure 5 and 6 It is shown in the middle. Figure 5 and Figure 6 The flux under different loads is shown as Hxnθ e The changes in these functions mean that they are also d-axis and q-axis currents (Id). d and I q The function of ).

[0142] The motor torque can be derived from the relationship between electrical and mechanical power. The equation, as follows, captures the effects of space harmonics. The first term gives the average torque, while the second term represents the torque fluctuations caused by space harmonics:

[0143]

[0144] The article described Figure 1 The purpose of controller 50 is to obtain motor torque (T) e And reduce the torque ripple component as described in equation (19). This can be achieved by controlling the current as described in equation (20), as follows. Alternatively, controller 50 can be configured to: via from Figure 3 Logic block 63 instruction zero ,inhibition Figure 1 The inherent current fluctuation of motor 14 ( The current fluctuations are caused by spatial harmonics and inverter nonlinearities such as lag time. Controller 50 can be optionally configured to handle specific harmonics or multiple different harmonics:

[0145]

[0146] Therefore in Figure 4 The section describes a representative design of a bandwidth-divided current regulator (i.e., harmonic compensation regulator (HC-REG) logic block 36). Similar to how current and magnetic flux are decomposed into fundamental and harmonic components as shown in equations (17) and (20) above, the current regulator can also be designed to control the fundamental and harmonic components:

[0147]

[0148] in It is a synchronous reference frame current regulator, for example Figure 4 Logic block 34 is designed to control the fundamental frequency component; while It is a harmonic reference frame controller, such as a bandwidth-divided harmonic compensation regulator 31, which is designed to control harmonic components, where Hxn can again be an nth-order harmonic.

[0149] Therefore, the voltage equations described in the above formulas (15) and (16) can then be written in complex vector form. ,as follows:

[0150]

[0151] in The apparent inductance term in vector form is obtained from equations (11) and (12). It is achieved through the incremental inductance matrix given below:

[0152]

[0153] back electromotive force term It can be intentionally ignored because it is considered Figure 1 The interference terms of controller 50 are therefore compensated as an additional term in controller 50.

[0154] Equation (22) can be transformed into the Laplace domain (or s-domain) and in the current domain. The object representation of motor 14 in the middle can be defined as:

[0155]

[0156] Here, It is a damping drag, which is added to improve the dynamic characteristics of the system. Fundamental component controller G c (S) is designed to control the damping object G p (s) makes Figure 1 The actual motor 14 behaves like a well-degraded performance object G. p (s) Same. G c (S) can be defined as:

[0157]

[0158] Gain K pdq and K idq It can be configured to achieve near-pole-zero cancellation. ,in It is the bandwidth of the synchronous frame current regulator, and It is the sampling frequency.

[0159] The bandwidth can vary linearly or according to the sampling frequency to maintain the high bandwidth and anti-interference characteristics of the system (i.e., motor 14). This can be understood without understanding the angular position θ. e Obtaining the changes caused ,because Configured to control the fundamental component. As shown in formula (18), the inductance term can be decomposed into the fundamental component and harmonic components. ,in, The inductance term is modified to be a function of the sampling frequency to maintain high bandwidth and anti-interference characteristics. As discussed in reference equation (18), the inductance term can be decomposed into the fundamental component and harmonic components.

[0160] Continuing this discussion, the frequency response of the aforementioned synchronous reference frame has bandwidth. Approximate first-order response:

[0161]

[0162] Synchronous current regulators can be rotated to specific harmonics. In a harmonic reference frame, this results in:

[0163]

[0164] Therefore, the gain was set as follows in an attempt to achieve near-zero pole-zero cancellation. ,in This is used to set the bandwidth scaling value of the harmonic reference system controller based on the synchronous reference system controller 50. Therefore, ,in It can be obtained from equation (24) without the fundamental component, as discussed with reference to equation (18). The inductance term can be decomposed into the fundamental component and harmonic components. ,in The sampling frequency is modified to maintain the system's high bandwidth and anti-interference characteristics.

[0165] Therefore, the effective decoupling object of equation (23) can be defined as:

[0166]

[0167] This expression yields the frequency response of the harmonic reference frame, which is centered at... Nearby bandpass system response:

[0168]

[0169] The discrete form of the above equation (24) is obtained by applying Can target Figure 4 (Logic block 34) is implemented. The discrete terms of equation (26) are in Figure 4 The frequency correction term is described in the text. To account for the typical discrete errors and sampling delays of a digital control system such as controller 60, a lookup table can be used for pre-configuration. (Block 52) represents the sampling period. In the alternative control logic 250L, additional current-to-flux conversion lookup tables 170 and 270 are used to output the fundamental and harmonic components, i.e., λ, respectively. dq and λ dqHxn . Figure 8 The configuration can be found in the above text. Figure 4An alternative configuration 136 to the harmonic current regulator logic block 36 described herein is presented below.

[0170] Figure 8 This gain configuration allows for high bandwidth and high interference rejection characteristics, while maintaining system stability even at low pulse rates. F e It is related to rotational speed A proportional synchronization frequency, while "low pulse rate" means operating at a high frequency or high speed for a given sampling frequency. Furthermore, this type of gain configuration understands flux. The changes in these parameters lead to precise control of the high-frequency components.

[0171] Therefore, the bandwidth partitioning used in this paper is a method of combining the controller with different bandwidth and frequency processing objectives, which allows the entire control system to achieve high bandwidth and disturbance rejection characteristics. As an example, a synchronous reference frame current regulator can be configured with high bandwidth, and it will be responsible for the average or basic current command by achieving average torque. A harmonic reference frame current regulator can be configured with partitioned bandwidth as described herein, and it will be responsible for tracking high-frequency pulsating signals designed for torque ripple reduction, tone injection, or current ripple reduction. This improves the tracking of multi-order (harmonic) high-frequency pulsating signals without any DC component and phase hysteresis error.

[0172] exist Figure 8 The design of the bandwidth-divided flux regulator is described in an exemplary embodiment. The voltage equations from equations (1) and (2) above can be written in flux form using the relationship between current and flux from equations (13) and (14):

[0173]

[0174] This equation can be written in complex vector form. ,as follows:

[0175]

[0176] Define time constant ,in Transforming to the Laplace domain (or s-domain) results in the object model in the flux domain:

[0177]

[0178] The basic flux controller or synchronization system flux regulator can be mathematically represented or defined as:

[0179]

[0180] This achieves an approximate first-order dynamic:

[0181]

[0182] The synchronous flux regulator can be rotated to a specific harmonic. In a harmonic reference frame, this results in:

[0183]

[0184] in It is the bandwidth of the harmonic flux regulator and is set to... ,and It is used to set the bandwidth scaling value of the harmonic reference system controller according to the synchronous reference system controller, and where and .

[0185] Harmonic flux modulators are typically used to inject small-amplitude, high-frequency signals, and This is usually small enough for such cases, and can be ignored if necessary:

[0186]

[0187] The effective decoupling object of equation (32) can be written as:

[0188]

[0189] This results in the frequency response of the harmonic reference frame, which is centered at... Nearby bandpass system response:

[0190]

[0191] The discrete form of the above equation (33) for the synchronous flux regulator is obtained by applying... Can target Figure 8 It was realized. Similarly, in Figure 8 The discrete form of equation (35) is described in the figure, where the frequency correction term is... To account for the typical discrete errors and sampling delays of digital control systems such as controller 60, a lookup table can be pre-configured, in which... Sampling period .

[0192] exist Figure 9 The discrete form of the equation (34) including the time constant term is described. Based on... Figure 8 Within the flux domain, rather than Figure 7 Controlling such as in the current domain Figure 1 A significant advantage of the AC motor 14 is that the cross-coupling and saturation effects that lead to a more precise level of control can be taken into account.

[0193] exist Figure 7 In the comparison, the harmonic components are controlled in the flux domain, while the fundamental component is controlled in the current domain. Since the variation in the harmonic reference frame flux is taken into account, this alternative control scheme remains the effective choice.

[0194] Return to brief reference Figure 4 Implemented using PI control logic, the harmonic current regulator can be divided by bandwidth (BW1, ..., BWn), for example, within a sub-block 36 for each of the (n) harmonic components, with corresponding blocks 44-n, 46-n, and 48-n, as shown in the figure. The outputs of each sub-block 36, ..., 36-N are summed at node N12 and limited at block 56, thereby reducing the harmonic compensation voltage component (V) dq * Hx Provided to the summation node N3, such as Figure 2 As shown and as described above.

[0195] The above Figure 5 and 6 This describes the effect of flux amplitude and phase on a given torque load, for example, a 100% torque load. Figure 5 ) and 50% torque load ( Figure 6 The flux linkages (FLX-L) contributing 68 and 168 Webers (Wb) to the d-axis and q-axis flux, respectively, are plotted on the vertical axis. Electrical angles (Elec. Ang.) in degrees (°) are plotted on the horizontal axis. Figure 5 and 6 The comparison revealed that the magnetic flux varies according to the electrical angle and torque load. This makes Figure 1 The electric drive system 11 is sensitive to the purposefully injected current and phase of this disclosure, and also involves the concept of a change in bandwidth division based on the operating point of the phase angle injection.

[0196] Selective audible tone injection: As mentioned above, in some applications, for example Figure 1In the battery-electric vehicle embodiment of the illustrated motor vehicle 10, due to the configuration of the motor 14 and the power line dynamics, it may be difficult to completely eliminate a given harmonic order, or it may be desirable to maintain a given harmonic order. Therefore, in the mechanical field, the described bandwidth division method enables the introduction of audible tones, such as the first or third harmonic, to distract the user from sounds emitted at other possible higher harmonics (e.g., the sixth or twelfth harmonic). Similarly, the introduction of tones can supplement other harmonic orders that may be generated during the operation of the motor 14. In this way, the teachings are not limited to eliminating undesirable harmonics, but may also, or alternatively, include the purposeful injection of harmonics to shape the NVH characteristics of the electric drive system 11. Thus, tone injection can be performed in addition to, or alternatively, noise reduction and the elimination of torque and current fluctuations.

[0197] Figure 7 The control logic 150L is described, which can be used as Figure 2 This is a variation or extension of the current-based method. That is, instead of processing in the current domain, this teaching can be applied to the flux domain. As will be understood, operation in the flux domain requires accurate knowledge of the d-axis and q-axis flux characteristics of motor 14 within its expected operating range. This information can be determined, for example, via offline testing and calibration, and then recorded. Figure 1 The memory (M) of the controller 50 shown.

[0198] Compared to Figure 2 The improved flux-domain-based control logic 150L includes current-to-flux mapping lookup tables 70 and 170 (“ The harmonic flux modulator logic block 72 (“HF-REG”) and filter 74 (“FILT”), such as a bandpass filter or a synchronous filter, are used. Lookup table 70 is used for a given harmonic compensation current component (I... dq * Hx Provides corresponding command harmonic compensation flux components (λ) dq * Hx At node N13, subtract the actual or estimated harmonic compensation flux component (λ) from the bandpass filter 74 from this value. dq Hxn), the difference is the flux error signal (arrow λ) dq * Hx, err Then, this error signal is compared with the current rotational speed (ω). e Together, they are provided as input to the harmonic flux regulator logic block 72.

[0199] Using discrete control topology Figure 7 The logic block 72 is shown in more detail below, and this topology is related to... Figure 4The topology shown is similar, except that... Figure 4 Outside of the proportional and integral gain blocks 44 and 46. Similar to in Figure 4 As shown, the frequency correction block 48 provides the rotational speed ω. e The correction value is a function of a specific harmonic (Hx1) and a time-domain parameter (Ts). In addition to the integrator block (z) mentioned above... -1 )54 and sampling interval (T) S )52, control logic 150L includes gain block 75 (“ω b1 ”, …, “ω bn "), where ω bn =2πf bn (F) sw ). Here, ω bn F is the bandwidth of harmonic flux regulator logic block 72, in radians per second, where (n) again applies to a specific harmonic frequency, as described elsewhere above. bn It is the bandwidth (in Hertz) of the harmonic flux regulator, and F sw It is TPIM 20 ( Figure 1 and 2 The switching frequency of the controller 50 is used, for example, as its sampling frequency. Therefore, the bandwidth varies linearly or otherwise depending on the switching frequency. The advantage of this method is that it ensures the stability of harmonic current regulation under different switching and sampling frequencies. Therefore, the harmonic compensation current component (Vdq*Hx) is output from the limiting block 56 to... Figure 2 Node N3.

[0200] This teaching helps to enable the implementation of related control methods, as will be readily understood by those skilled in the art. In exemplary embodiments, for example, Figure 1 The controller 50 can evaluate the above-mentioned activation conditions to determine whether the implementation of torque and current ripple elimination technology is guaranteed. When the activation conditions are met, the controller 50 can identify specific harmonic components to be processed, such as 3rd, 6th and / or 12th order harmonic components.

[0201] Then, controller 50 determines the required d-axis and q-axis current commands based on the rotational speed and motor torque, as well as the phase injection needed to eliminate current and torque fluctuations and, if possible, to inject selected harmonics or introduce audible tones. As part of this method, controller 50 can scale the harmonic current commands to a function of the motor speed and then sum the various harmonic current commands. Controller 50 engages synchronization and harmonic current regulator 36 ( Figure 2 After bandwidth division, the required phase voltage command for energizing motor 14 is finally generated.

[0202] Offline, this method may include determining the filling Figure 2 ,3 The required values ​​for lookup tables 4 and 7 are used. For example, on a test bench or laboratory setting, the current command and phase required to eliminate torque ripples of selected harmonics in motor 14 can be determined. As part of this effort, the implied objects can be modeled and characterized, where, in this case, the objects include motor 14 and the coupled load. NVH analysis can be performed under different torque loads and rotational speeds of motor 14. A similar approach can be used to select the tone injection of harmonics. Subsequently, the controller 50 in operation generates harmonic current and phase commands in real time to eliminate torque and current ripples, and reduce... Figure 1 Acoustic noise in the electric drive system 11.

[0203] In a non-limiting exemplary application of this teaching, a user can configure the processing of two harmonic orders separately, such as Hx1 = 6 and Hx2 = 12, and selectively enable control logic 50L or 150L for Hx1 and Hx2 for the corresponding torque and speed operating regions. For harmonic order Hx1, torque ripples can be eliminated by configuring current amplitude and phase blocking for a given torque and speed operating region. Figure 3 The zero-instruction generation logic block 63 can be configured to eliminate current fluctuations in specific Hx1 torque and speed operating regions. By instructing zero to the configured region, the controller compensates for voltage (i.e., V) via instruction. qHx This attempts to force the current of a specific harmonic to zero. Simultaneously, the amplitude and phase blocks of Hx2 can be configured to inject acoustic tones to disperse the low-frequency content of the harmonic order Hx1. Alternatively, the processing of harmonic orders Hx1 and Hx2 can be configured to eliminate torque and current fluctuations in selected torque and speed regions.

[0204] Figure 12 and 13 The possible reductions in vibration and acoustic noise for baseline acceleration are shown separately. The horizontal axis represents the reduction in revolutions per minute (RPM). AVG The average speed of motor 14 is expressed in units of decibels (dB), with the vertical axis representing the average speed. Trace T1 forms the baseline performance for this representative acceleration in the absence of this teaching, while trace T2 represents the performance under the same conditions using the disclosed harmonic division strategy. A typical benefit of the invention is the reduction in vibration and noise at higher rotational speeds (e.g., above about 1000 RPM in this example case), which correspond to a speed range that is generally not solvable in a harmonic sense using conventional methods.

[0205] Although this teaching is represented as corresponding control logic and component logic blocks, those skilled in the art will recognize herein the basic methods used for controlling the operation of the rotary motor 14. Therefore, it is possible to... Figure 1The instruction 100 is encoded so that the processor P of the controller 50 executes the instruction 100, causing the controller 50 to... Figure 2 The harmonic compensation regulator 31 receives the command torque from the motor 14 ( ) and rotational speed (ω) e Then, in response to the group's enable conditions (arrow CC) ENBL ) via harmonic compensation regulator 31 using command torque ( ) and rotational speed (ω) e ) Calculate the dq harmonic compensation current for one or more predetermined harmonic orders (( ) and voltage ( As described above, the harmonic compensation current and voltage are configured to eliminate torque and current fluctuations at a predetermined harmonic order.

[0206] This method may include using the dq harmonic compensation current (( ) and voltage ( Add them to the dq current and voltage commands respectively. and ), to generate the adjusted dq current command ( ) and the adjusted dq voltage command ( Subsequently, the method may include using adjusted dq current and voltage commands (). and To control Figure 1 Operation of motor 14.

[0207] This method can handle multiple harmonic orders, in which case... Figure 2 The bandwidth-divided harmonic compensation modulator 31 can be configured to divide the dq harmonic compensation current for each of the multiple harmonic orders. Added together, and similarly for each of the multiple harmonic orders, the dq harmonic compensation voltage ( Together, they generate harmonic compensation current and voltage respectively. )and( ).

[0208] Implementations of the method may include via Figure 2 The torque-to-current logic block 30 of the controller 50 depicted in the figure is based on the instruction torque ( ), rotational speed (ω) e ) and DC bus voltage level (V dc ) generates dq current command ( As described above, logic block 30 can be implemented as a lookup table indexed or referenced by instruction torque, rotational speed, and DC bus voltage level.

[0209] Other aspects of this method may include obtaining a regulated dq current command ( Subtract the actual dq current of motor 14 (I) dq To obtain the dq current error value (I) dq,Err Using the dq current error value (I) dq,Err The regulated dq voltage command is generated by the harmonic compensation regulator 31. ), will adjust the dq voltage command ( ) converted to phase voltage command (V * abc ), and phase voltage command (V * abc Provided to Figure 1 and 2 The TPIM 20, thereby energizing the motor 14.

[0210] exist Figure 2 In the illustrated embodiment, the method may include: determining and outputting the dq harmonic compensation current via FF HC-GEN logic block 32 ( The dq harmonic compensation voltage is determined and output via HC-REG logic block 36. ); and through such Figure 3 The scaling logic blocks 60, ..., 60-n of the FF HC-GEN logic block 32 shown enable the dq harmonic compensation current ( ) Inclined transformation. This method may require selectively applying individual d-axis and q-axis harmonic compensation currents (I) via a null block, depending on the commanded torque and rotational speed. dHx1 , …, I dHxn and I qHx1 ,…, I qHxn Return to zero.

[0211] like Figure 4 As shown, Figure 2 The HC-REG logic block 36 may include multiple separate control loops for each corresponding harmonic order, wherein each loop has selectable proportional and integral gain blocks 44 and 46 and a frequency correction block 48. The dq harmonic compensation voltage is determined and output via the HC-REG logic block 36. This may include: calculating the respective harmonic-specific dq harmonic compensation voltage for each of the (n) harmonic orders; and then calculating the respective harmonic-specific dq harmonic compensation voltage (V). dqHx ) are added together to generate the commanded dq harmonic compensation voltage ( ).

[0212] As mentioned above, it can be used Figure 2The harmonic compensation modulator 31 injects an audible tone at a predetermined harmonic order. In an alternative embodiment, the modulator 31 also operates in the flux domain rather than the current domain. In the flux domain, the method may be adapted to include: […]. Figure 7 The dq harmonic compensation current of the FF HC-GEN logic block 32 ( Converted to dq harmonic compensation magnetic flux ; Calculate the dq harmonic compensation flux error value ; Transmission dq harmonic compensation magnetic flux error value arrive Figure 7 The HF-REG logic block 72; and then using dq harmonics to compensate for the flux error value. The dq harmonic compensation voltage is determined and output via HC-REG logic block 72. For example, by using lookup tables, calculations, or other methods.

[0213] The detailed description and accompanying drawings support and describe the present teachings, but the scope of the present teachings is defined only by the claims. While some best modes and other embodiments for carrying out the present teachings have been described in detail, various alternative designs and embodiments exist for practicing the present teachings as defined in the appended claims. Furthermore, this disclosure expressly includes combinations and sub-combinations of the elements and features presented above and below.

Claims

1. A method for controlling the operation of a rotating electric motor, the method comprising: The controller uses a harmonic compensation regulator to receive the motor's command torque and rotational speed. In response to a set of enable conditions from a plurality of enable logic blocks, the bandwidth-divided harmonic compensation regulator calculates dq harmonic compensation current and dq harmonic compensation voltage for one or more predetermined harmonic orders using the commanded torque and the rotational speed, wherein the harmonic compensation current and harmonic compensation voltage are configured to selectively eliminate torque ripple and current ripple in the one or more predetermined harmonic orders. The dq harmonic compensation current and the dq harmonic compensation voltage are respectively applied to the dq current command and the dq voltage command to generate the regulated dq current command and the regulated dq voltage command. as well as The operation of the motor is controlled using the regulated dq current command and the regulated dq voltage command, including eliminating one or more of the torque and current fluctuations in one or more predetermined harmonic orders. Wherein, the one or more predetermined harmonic orders include a plurality of harmonic orders, and wherein the bandwidth-divided harmonic compensation regulator is configured to sum the dq harmonic compensation current and dq harmonic compensation voltage for each of the plurality of harmonic orders, thereby generating the harmonic compensation current and the harmonic compensation voltage. The bandwidth-division harmonic compensation regulator includes a feedforward harmonic current generation logic block and a harmonic current regulator logic block. The method includes: determining and outputting the dq harmonic compensation current via the harmonic current regulator logic block; determining and outputting the dq harmonic compensation voltage via the harmonic current regulator logic block; and scaling the dq harmonic compensation current via a scaling block of the feedforward harmonic current generation logic block. The feedforward harmonic current generation logic block is divided into multiple sub-blocks for processing the multiple harmonic orders, and each of the multiple sub-blocks is selectively enabled by a corresponding one of the multiple enable logic blocks. The method further includes: wherein the motor is connected to a traction power inverter module, and the bandwidth division harmonic compensation regulator operates in the flux domain; and the method also includes: The dq harmonic compensation current from the feedforward harmonic current generation logic block is converted into dq harmonic compensation flux. Calculate the dq harmonic compensation flux error value; Send the dq harmonic compensation flux error value to the harmonic flux regulator logic block; and The dq harmonic compensation flux error value is used to determine and output the dq harmonic compensation voltage via the harmonic current regulator logic block. The harmonic current regulator logic block includes multiple individual control loops for each corresponding harmonic order, each loop having a discrete proportional-integral control logic block, a frequency correction block, and a gain block. The determination and output of the dq harmonic compensation voltage via the harmonic current regulator logic block includes: calculating a corresponding harmonic-specific dq harmonic compensation voltage for each of the harmonic orders, and adding the corresponding harmonic-specific dq harmonic compensation voltages together to generate the dq harmonic compensation voltage. The frequency correction block provides correction values ​​as a function of the rotational speed, the corresponding harmonics in the harmonic order, and time-domain parameters. The gain provided by the gain block is the bandwidth of the harmonic current regulator logic block, which varies linearly according to the switching frequency of the traction power inverter module.

2. The method of claim 1, wherein the motor is connected to a DC voltage bus having a DC bus voltage level, the method further comprising generating the dq current command using a torque-to-current logic block of the controller based on the commanded torque, the rotational speed and the DC bus voltage level.

3. The method of claim 2, wherein the torque-to-current logic block is a lookup table indexed or referenced by the command torque, the rotational speed, and the DC bus voltage level.

4. The method according to claim 1, wherein the method further comprises: The actual dq current of the motor is subtracted from the adjusted dq current command to obtain the dq current error value; The dq current error value is used to generate an adjusted dq voltage command via the bandwidth division harmonic compensation regulator logic block. Convert the regulated dq voltage command into a phase current command; and The phase current command is provided to the traction power inverter module to excite the motor.

5. The method of claim 1, wherein the feedforward harmonic current generation logic block includes a current amplitude lookup table configured to provide separate d-axis and q-axis harmonic compensation currents, and a phase injection lookup table configured to output harmonic compensation phase adjustment.

6. The method of claim 5, wherein the feedforward harmonic current generating logic block comprises an empty block or a zero block, the method comprising selectively invalidating or zeroing separate d-axis and q-axis harmonic compensation currents via the empty block or zero block according to the commanded torque and the rotational speed.

7. The method of claim 1, further comprising using the bandwidth-divided harmonic compensation modulator to selectively inject audible tones at predetermined harmonic orders.

8. An electric drive system, comprising: Battery pack; A rotating electric motor connected to a load; A traction power inverter module connected to the battery pack and the rotating motor; as well as The controller, which communicates with the traction power inverter module, is configured to: The controller receives the command torque and rotational speed of the motor via a bandwidth-divided harmonic compensation regulator. In response to a set of enable conditions from a plurality of enable logic blocks, the bandwidth-divided harmonic compensation regulator calculates dq harmonic compensation current and dq harmonic compensation voltage for one or more predetermined harmonic orders using the commanded torque and the rotational speed, wherein the harmonic compensation current and harmonic compensation voltage are configured to eliminate torque and current fluctuations in the one or more predetermined harmonic orders. The dq harmonic compensation current and dq harmonic compensation voltage are applied to the dq current command and dq voltage command respectively to generate the regulated dq current command and regulated dq voltage command. as well as The operation of the motor is controlled using the adjusted dq current command and the adjusted dq voltage command. Wherein, the one or more predetermined harmonic orders include a plurality of harmonic orders, and wherein the bandwidth-divided harmonic compensation regulator logic block is configured to add together the dq harmonic compensation current and the dq harmonic compensation voltage for each of the plurality of harmonic orders, thereby generating the harmonic compensation current and the harmonic compensation voltage, respectively. The bandwidth-division harmonic compensation regulator includes a feedforward harmonic current generation logic block and a harmonic current regulator logic block. The controller is further configured to: determine and output the dq harmonic compensation current via the harmonic current regulator logic block; determine and output the dq harmonic compensation voltage via the harmonic current regulator logic block; and cause the dq harmonic compensation current to be scaled via a scaling block of the feedforward harmonic current generation logic block. The feedforward harmonic current generation logic block is divided into multiple sub-blocks for processing the multiple harmonic orders, and each of the multiple sub-blocks is selectively enabled by a corresponding one of the multiple enable logic blocks. The bandwidth-division harmonic compensation modulator operates in the flux domain and further includes: The dq harmonic compensation current from the feedforward harmonic current generation logic block is converted into dq harmonic compensation flux. Calculate the dq harmonic compensation flux error value; Send the dq harmonic compensation flux error value to the harmonic flux regulator logic block; and The dq harmonic compensation flux error value is used to determine and output the dq harmonic compensation voltage via the harmonic current regulator logic block. The harmonic current regulator logic block includes multiple individual control loops for each corresponding harmonic order, each loop having a discrete proportional-integral control logic block, a frequency correction block, and a gain block. The determination and output of the dq harmonic compensation voltage via the harmonic current regulator logic block includes: calculating a corresponding harmonic-specific dq harmonic compensation voltage for each of the harmonic orders, and adding the corresponding harmonic-specific dq harmonic compensation voltages together to generate the dq harmonic compensation voltage. The frequency correction block provides correction values ​​as a function of the rotational speed, each corresponding harmonic order in the harmonic order, and time-domain parameters. The gain provided by the gain block is the bandwidth of the harmonic current regulator logic block, which varies linearly according to the switching frequency of the traction power inverter module.

9. The electric drive system according to claim 8, wherein, The controller is configured to use the bandwidth-divided harmonic compensation modulator logic block to selectively inject audible tones at predetermined harmonic orders.

10. The electric drive system according to claim 8, wherein, The controller is also configured to: The actual dq current of the motor is subtracted from the adjusted dq current command to obtain the dq current error value; The dq current error value is used to generate an adjusted dq voltage command via the bandwidth division harmonic compensation regulator logic block. The adjusted dq voltage command is converted into a phase current command; and The phase current command is provided to the traction power inverter module to excite the motor.

11. The electric drive system according to claim 8, wherein, The feedforward harmonic current generation logic block includes lookup tables configured to provide separate d-axis and q-axis harmonic compensation currents, and a phase injection lookup table configured to provide harmonic compensation phase adjustment.

12. The electric drive system according to claim 11, wherein, The feedforward harmonic current generation logic block includes an empty block or a zero block, and the controller is also configured to selectively invalidate or zero individual d-axis and q-axis harmonic compensation currents via the empty block or zero block based on the commanded torque and the rotational speed.

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