Motor drive calibration, verification and efficiency enhancement

Abstract

Methods, systems, and apparatus for motor drive calibration, verification, and efficiency improvements are disclosed herein. One motor controller for calibration includes a processor and memory and instructions stored in the memory and executable by the processor to identify vehicle and / or motor frequency responses during vehicle operation and drive a converter using a motor and a dynamic motor to provide source excitation based on the identified frequency responses.

Description

Technical Field

[0001] The present disclosure relates to motor management methods, apparatus and systems, and in particular to motor drive calibration, verification and efficiency improvement. Background Art

[0002] As used herein, the phrase "electrical machine" is intended to be broadly understood to include machines that operate as either or both a motor and a generator. When an electric machine operates as a motor, it converts electrical energy into mechanical energy. When operating as a generator, an electric machine converts mechanical energy into electrical energy.

[0003] Electric motors and generators are used in a wide variety of applications and under a wide variety of operating conditions. In general, many modern electric motors have relatively high energy conversion efficiencies. However, the energy conversion efficiency of most electric motors can vary significantly based on the load at which they are operating. Many applications require the motor to operate under a wide variety of different operating load conditions, which means that the motor will not usually operate as efficiently as it could when operating in continuous mode.

[0004] For example, for any given motor speed, motor efficiency tends to drop as the motor load is above or below the most efficient load. In some performance areas, motor efficiency tends to drop relatively quickly.

[0005] If the operating conditions can be controlled so that the motor is almost always running at or near its most efficient point, the energy conversion efficiency of the motor will be very good. It has been proposed to pulse the motor during operation to achieve a condition where it runs at its most efficient point more frequently.

[0006] When controlling a machine in pulse operation, a measurement or estimate of the torque output must be determined over a period of time. One type of pulse motor management is called dynamic motor drive (DMD).

[0007] Traditional methods of determining this torque output are to evaluate the measured or estimated torque as a function of time, for example, by averaging the most recent estimated or measured values ​​of the torque or using a digital filter. When trying to use these methods with a motor that runs using pulses, such as in a DMD process, this can lead to inaccurate torque values ​​because these methods can produce inconsistent results.

[0008] With regard to calibrating such motors, there are large differences in the noise, vibration and harshness (NVH) response among different vehicles utilizing the motors. Manually calibrating each vehicle model to reduce or minimize NVH is very labor intensive and may deter potential vehicle manufacturers from adopting DMD on their platforms. The proposed solution will add automatic calibration and adaptive capabilities to the DMD system.

[0009] Current technology requires manual calibration of DMD frequency selection for different speeds and loads of the motor. This process requires extensive testing for a single model and needs to be repeated for each model of each potential vehicle manufacturer.

[0010] Furthermore, in battery powered applications, such as electric vehicles, the performance of the battery is also important to ensure overall optimal efficiency and battery life, which can extend the vehicle's range. It has been found that under certain pulse conditions, the power loss of the battery can be significant. Experiments have found that pulse current can cause power loss under certain conditions. The power loss is related to the on-phase of the pulse due to the I 2 The lower terminal voltage is related to higher resistance losses proportional to R, where I is the current and R is the internal resistance of the cell. Mitigating these losses is important to maximizing DMD gain.

[0011] Furthermore, extensive pre-calibration is required to ensure that the DMD operates optimally in all possible situations, which takes into account speed, torque, machine temperature, battery state of charge (SOC), battery temperature, battery state of health (SOH), etc. Some possible situations may not be fully considered, causing DMD operation to increase rather than reduce power losses compared to continuous operation in these situations. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a functional block diagram that diagrammatically illustrates a motor control architecture according to an embodiment of the present disclosure.

[0013] Figure 2 is a diagram illustrating a pulse drive signal for a motor that may be used with embodiments of the present disclosure.

[0014] Figure 3 is a flow chart illustrating a motor control scheme according to an embodiment of the present disclosure.

[0015] Figure 4 is an equivalent circuit model (ECM) that can be used to estimate battery system dynamics and pulse power losses and can be used in embodiments of the present disclosure.

[0016] Figure 5 are examples of sample ECM model parameters that may be used with embodiments of the present disclosure.

[0017] Figure 6 is an example of a pulse width modulated square wave and its dimensional elements that may be used with embodiments of the present disclosure.

[0018] Figure 7Shown is the trend of equivalent resistance over a range of duty cycles that can be achieved using embodiments of the present disclosure at a given frequency.

[0019] Figure 8 is a graphical representation of the power loss of pulsed current at average current rate (C-rate) and pulse duty cycle using an embodiment of the present disclosure.

[0020] Fig. 9A is an example of a speed of a motor at which embodiments of the present disclosure may benefit.

[0021] Fig. 9B is an example of the amount of torque of an electric machine from which embodiments of the present disclosure may benefit.

[0022] Fig. 9C is an example of a normalization scheme for processing torque variations during a sampling period according to an embodiment of the present disclosure.

[0023] Fig.10 is a method embodiment according to the present disclosure.

[0024] Fig.11 is another method embodiment according to the present disclosure. DETAILED DESCRIPTION

[0025] The present disclosure provides a better way to utilize pulse motor management through motor drive calibration, verification and efficiency improvement. This can be achieved by implementing a new motor pulse control method.

[0026] Historical practice of motor control has been developed for running electric motors with continuously variable torque control. For example, when the motor is running under a continuous power application scheme, if it is desired to deliver 100 Newton meters (Nm) of torque, the control system that controls the motor delivers 100 Nm of electric torque. However, in some implementations, it can be found that there are advantages to delivering a larger amount of torque in a shorter period of time (intermittently pulsing torque delivery). This pulsed operation can be more efficient and is therefore more desirable. This technology is generally referred to as dynamic motor drive (DMD).

[0027] In this case, if the desired torque output is 100Nm over a period of time, and if the most efficient torque production of the particular motor being used is 200Nm, the control system will deliver 200Nm of torque over 50% of the time period, providing the same total 100Nm over the period, but doing so more efficiently than providing a steady 100Nm over the entire period. The 200Nm torque delivery can be delivered in pulses with time intervals. For example, a time period can have twenty segments, ten of which are 200Nm and ten of which are 0Nm (e.g., alternating 200Nm, 0Nm, 200Nm, 0Nm...). For various other motors, other implementation arrangements are possible and can provide more desirable operation, such as providing more effective vibration control, which is an important factor in NVH improvements.

[0028] Such pulse techniques generally involve pulse control of electric machines (e.g., motors and generators) that would otherwise be operated in a continuous manner. Such pulse techniques can improve the energy conversion efficiency of the electric machine when operating conditions permit. More specifically, under selected operating conditions, the electric machine is intermittently driven (pulsed) at a more efficient energy conversion operating level than would be obtained with conventional continuous motor control to more energy efficiently deliver a desired average torque.

[0029] The pulses can be adjusted based on pulse width modulation (varying the duration that the motor is on) or pulse density modulation (the number of pulses in a specific time period). The pulses can be adjusted in these ways based on the torque output requirements as well as performance and efficiency considerations.

[0030] Some of the goals of this pulse technology are to produce accurate and responsive torque delivery, but torque control must also be achievable. For example, delivering torque in such a way that it causes the motor to operate in a performance region it was not designed to operate in would be a case of torque loss control, as this could cause safety or equipment damage issues.

[0031] Many types of electric machines are traditionally driven by a continuous (although possibly varying) drive current when the machine is used as a motor to deliver a desired torque output. The drive current is often managed by controlling the output voltage of a power converter (e.g., an inverter) that serves as the voltage input to the motor. In contrast, the power output of many types of generators is managed by controlling the magnetic field strength, which can be achieved, for example, by controlling the excitation current supplied by an exciter to the rotor coils.

[0032] Using pulse control, the machine's output is modulated between "torque on" and "low torque" states in an intelligent and intermittent manner to: (1) meet operating demands while (2) improving overall efficiency. In other words, under selected operating conditions, the motor is intermittently driven at a more efficient energy conversion operating level ("torque on" state) to deliver the required output.

[0033] During the time period between pulses, the machine ideally does not produce or consume any torque (a "low (e.g., zero) torque" state). Conceptually, this can be thought of as "turning off" the motor.

[0034] In some implementations, this may be accomplished by effectively "turning off" the motor, e.g., by cutting off the drive current to the motor or the field current to the generator. However, in other implementations, the motor may be controlled during the "low torque" state in a manner that attempts to make the torque produced by the motor zero or as close to zero as may be practical or appropriate for a particular machine.

[0035] In particular, for electric motors that induce a magnetic field in the rotor via an electromagnetic field in the stator ('AC induction motors), the time constant of the magnetic field generation may require that some level of continuous 'field' current be maintained in the motor. In some implementations, any power converter used in conjunction with the motor may also be effectively shut down for at least part of the 'low torque' period.

[0036] The control of the motor (eg, feedback, feedforward, etc.) is based on a continuous or effectively continuous control strategy. That is, at each moment during the use of the motor, its control system is utilizing a control strategy to determine whether the motor is activated.

[0037] In some embodiments, the motor is driven in a pulsed manner when the desired output is less than a specified output level for a given motor speed, and is driven in a continuous manner when the desired motor output is greater than or equal to the specified output level.

[0038] In some embodiments, a power converter is used to control the output of the motor. Depending on the application, the power converter can take the form of an inverter, a rectifier, or other suitable power converter.

[0039] The frequency of the pulses can vary widely depending on the requirements of any particular application. For example, in various embodiments, the motor alternates between the first and second output levels at least 10, 100, or 1000 times per second.

[0040] Some embodiments discussed herein provide automatic calibration of DMD applications for NVH. Such embodiments can be used to automatically calibrate pulse frequencies for different speeds and loads based on in-situ measurements of NVH responses, for example, using only production sensors and actuators already associated with the motor in the vehicle, thereby eliminating the need for additional components. For example, in one method,

[0041] Step 1: Use the motor inverter in an electric vehicle (or other application) as the excitation source to measure the NVH response of the vehicle and identify resonant and high response areas.

[0042] Step 2: Use the measured response curve to automatically adjust the DMD calibration to maintain acceptable NVH under all operating conditions.

[0043] Step 3 (optional): Fine-tune auto-calibration based on operational response. In this way, auto-calibration can be done in the vehicle at the time of use.

[0044] Further, as discussed above, it has been found that under certain pulse conditions, the power losses of the battery can be significant, but these losses can be minimized by appropriate selection of torque / current modulation parameters. Various embodiments of the present disclosure utilize equivalent circuit models (ECMs) that fit experimental data, which can analytically characterize the approximate losses. These can be integrated into offline or online optimization to select DMD calibration parameters that will maximize the system efficiency gain. In addition to the battery, other components and auxiliary equipment in the high voltage distribution system can also be included in the ECM.

[0045] Furthermore, a real-time on-board diagnostic monitor as discussed with respect to various embodiments of the present disclosure may help prevent situations in which the DMD negatively impacts energy loss.

[0046] In these embodiments, the performance of the DMD is monitored in the field (on the vehicle) to ensure that the DMD is performing as expected. One approach discussed with respect to embodiments of the present disclosure is to turn the DMD on and off during relatively stable torque / speed periods and compare the battery output power / current between the DMD and continuous mode (minus the DCDC converter input power / current for the 12V accessory) to ensure that the DMD gain meets pre-calibrated expectations within some threshold.

[0047] Correction factors for "steady-state" torque and speed changes can be applied to normalize the measured power / current to a reference torque / speed. The inverter input power can also be used (instead of the battery power / current), which has two potential disadvantages: (1) excess losses in the battery will not be captured, and (2) the sampling rate of the inverter internals may not be fast enough to resolve the DMD pulses for energy integration.

[0048] Separate from the on / off switching approach, in another embodiment, the individual DMD power losses can be monitored and compared to the expected power losses / currents from pre-calibrated maps. This approach may be used during relatively stable torque / speed periods, but can be accomplished more quickly because only DMD mode is required (i.e., no transition to continuous mode and sampling during continuous mode is required).

[0049] If the DMD gain and / or DMD power loss in continuous mode is as expected, no additional action is needed. However, if the DMD is not performing well for continuous mode, or the DMD power loss is higher than expected, this may trigger some action. Some example actions are: stop using the DMD in the speed / torque window of the test, throw an error, or change the DMD "turn on" torque. In some embodiments, if the DMD is disabled in some operating region, a future retest of that region showing expected DMD behavior can re-enable the DMD there.

[0050] This monitoring type algorithm may be most useful for trimming the top of the DMD operating map (high torque / duty cycle), but stable torque conditions may not be encountered frequently there (lower "cruise" torques are more likely to be stable). However, the "DMD only" monitoring method may be more suitable for higher torques that are only stable for short periods of time.

[0051] Thus, various embodiments of the present disclosure may capture poor performance of the DMD under any conditions encountered without specific knowledge of the root cause of the problem, and may take mitigating actions to prevent the motor from operating underperforming and increasing vehicle energy losses.

[0052] A machine controller and motor system are described for implementing all of the above functionality. In various embodiments, the system may be configured to operate as a motor, a generator, or as a motor / generator.

[0053] In various embodiments, the motor can be: an induction motor; a switched reluctance motor; a synchronous AC motor; a synchronous reluctance motor; a switched reluctance motor; a permanent magnet synchronous reluctance motor; a hybrid permanent magnet synchronous reluctance motor; an externally excited AC synchronous motor; a permanent magnet synchronous motor; a brushless DC motor; an electrically excited DC motor; a permanent magnet DC motor; a series-wound DC motor; a shunt DC motor; a brushed DC motor; a compound DC motor; an eddy-current machine; an AC linear motor; an AC mechanically commutated motor or a DC mechanically commutated motor; or an axial flux motor.

[0054] In the following detailed description, reference is made to the accompanying drawings which form a part hereof. The drawings show, by way of illustration, how one or more embodiments of the disclosure may be practiced.

[0055] These embodiments are described in sufficient detail to enable one of ordinary skill in the art to practice one or more embodiments of the present disclosure. It should be understood that other embodiments can be utilized, and process, computerization and / or structural changes can be made without departing from the scope of the present disclosure.

[0056] As will be understood, the elements shown in the various embodiments herein may be added, exchanged, combined and / or eliminated to provide many additional embodiments of the present disclosure. The proportions and relative scales of the elements provided in the accompanying drawings are intended to illustrate embodiments of the present disclosure and should not be considered to be limiting.

[0057] The figures herein follow a numbering convention in which the first digit or digits correspond to the drawing figure number and the remaining digits identify an element or component in the drawing.

[0058] As used herein, "one" or "a number of" something may refer to one or more such things. For example, "a number of valves" may refer to one or more valves. As used herein, "a number of" refers to two or more things.

[0059] Figure 1 is a functional block diagram that diagrammatically illustrates a motor control architecture according to an embodiment of the present disclosure. There are a wide variety of different motors, and each machine has its own unique efficiency characteristics. Therefore, the operating region where pulse control can provide efficiency gains will vary significantly based on factors including the specific motor characteristics and the current operating rotor speed.

[0060] In many applications of electric motors, power is converted to the voltage, current, and waveform required by the motor or the power of a power source is converted to the voltage, current, and waveform required by the motor by using a power converter (e.g., an inverter). For example, an inverter is used to convert power received from a DC power source (such as a battery or a capacitor) to the appropriate AC input power applied to the motor.

[0061] The energy conversion efficiency of a power converter will also typically vary over the operating range of the converter. Therefore, when optimizing the control of an electric motor that is part of an inverter / motor combination, it is desirable to consider the energy conversion efficiency of the entire inverter / motor system, rather than the energy conversion efficiency of the individual motors. Preferably, the pulse control of the motor will be modeled to take into account the efficiency of any / all components that affect energy conversion during the pulse. For example, when the power for the motor is drawn from a battery, the power transfer efficiency of the battery, cable losses between components, and any other loss factors may be considered in addition to the inverter and motor efficiencies when determining the motor drive signal that delivers the best energy conversion efficiency.

[0062] In general, the overall energy conversion efficiency of a power converter / motor system is a function of the product of the converter conversion efficiency times the motor conversion efficiency times the transfer efficiency of the other components. Therefore, it should be understood that the parameters of the pulse drive signal with the maximum system energy conversion efficiency may be different from the parameters that provide the best energy conversion efficiency for the motor itself.

[0063] Figure 1 A control architecture suitable for controlling a motor in the manner described is shown. In this embodiment, system 100 includes a machine controller 110, a number of connected components 111 (e.g., in a vehicle, the connected components may be sensors such as microphones and accelerometers that provide data to the machine controller), a pulse controller (pulse generator) 120, a power source / receiver 130, a power controller / converter 150, and a motor 160.

[0064] The pulse controller 120 is responsible for controlling / directing the pulse timing of the motor 160 when pulse operation is required. Figure 1 In the illustrated embodiment, the pulse controller is shown as a separate component from the machine controller 110 to facilitate explanation of its functionality. However, in various embodiments, the pulse controller may be implemented as part of the machine controller 110, as a separate component, as part of the power controller / converter 150, or in other suitable forms.

[0065] When the motor 160 being operated is an electric motor, the machine controller functions as a motor controller, and the power controller / converter 150 is responsible for converting the power 132 received from the power source 130 into a form suitable for driving the motor 160. In embodiments where the power source / receiver can directly supply or receive power in the form required or output by the motor, the power controller 150 can conceptually take the form of a switch or logic multiplier that simply turns the motor on and off to facilitate the required pulses.

[0066] The power source / receiver 130 can take any suitable form. In some implementations, the power source / receiver can take the form of a battery or a capacitor. In other implementations, the source can be an electrical grid (e.g., "wall power"), a photovoltaic system, or any other available source. Similarly, the receiver can be an electrical load (such as an electric machine or appliance, a building, a factory, a home, etc.), a grid, or any other system that uses or stores electricity.

[0067] The power controller / converter 150 may also take a variety of different forms. When the power supply / receiver 130 is a DC power supply and the motor 160 is an AC motor, the power controller / converter 150 may take the form of an inverter. Conversely, when the power supply / receiver 130 is a DC power receiver and the motor 160 is an AC generator, the power controller / converter 150 may take the form of a rectifier. When both the power supply / receiver 130 and the motor are AC components, the power controller / converter 150 may include a bidirectional or 4-quadrant power converter.

[0068] exist Figure 1 , the requested output is labeled 113, the torque delivered or received by the motor is labeled 161, and the motor / generator speed is labeled 164. In some embodiments, the machine controller 110 includes a data structure 115 (e.g., a lookup table) that serves as a pulse operation map that defines operating regions where pulse motor control is required and / or appropriate, as well as specific duty cycles suitable for specific operating conditions.

[0069] Once the desired duty cycle is determined, the duration and nature of the pulses used to drive the motor can be determined / generated in a variety of ways. As will be described in more detail below, one relatively simple approach is to use a pulse width modulation (PWM) controller as the pulse controller 120 .

[0070] exist Figure 1 , a logic multiplier 123 is shown as multiplying a pulse control signal 125 by a power level signal 119 output by the machine controller 110 to produce a power converter control signal 128. It should be understood that the logic multiplier 123 is shown for explanation purposes, and in practice, the functionality of the multiplier 123 may be implemented by the machine controller 110, the power converter 150, or in other suitable ways. For example, in some embodiments, the machine controller 110 may simply set the output of the power converter 150 to zero during the "off" phase of the duty cycle, and set it to a desired operating output level (e.g., the most efficient output level for the current machine speed) during the "on" phase of the duty cycle.

[0071] With regard to the calibration aspects of the present disclosure, one embodiment includes real-time system identification of vehicle / generator frequency response. In this process, the motor and DMD converter (e.g., inverter) are used to provide source excitation for the system identification (ID) process. For example, the inverter can be made to output a current waveform with an excitation frequency of interest. These can be in the form of steady state (e.g., step, slow sweep sine, etc.), random, periodic (e.g., chirp, pseudo-random, periodic random, etc.), transient (e.g., burst, impact, step relaxation, etc.) or other configurations. This step does not require any external test equipment, such as a vibrator or hammer, which may be beneficial because the process can be performed on the motor during normal operation rather than on a test platform. This calibration embodiment may include measuring noise and vibration using an on-board accelerometer / sensor in the vehicle (e.g., a vehicle typically has a microphone for Bluetooth, wireless communication, and / or entertainment systems, and an accelerometer may be located on the vehicle, for example, for collision detection).

[0072] The motor controller / vehicle control unit / computing device will then process the inputs and outputs from these components and calculate the frequency response functions (e.g., with respect to noise and vibration) of different locations (e.g., this could be all available sensors or a subset thereof). Through this process, peaks can be detected to identify resonances, or the data can be compared to calibrable thresholds of the associated frequency response function (FRF). Note that this step can be done during normal motor operation, even without turning on the DMD. Using the superposition principle, small amplitude perturbations can be added to the motor torque on top of the stable / DC torque output.

[0073] In some embodiments, automatic calibration of the frequency selection and / or avoidance tables can be utilized. For example, they can be used in the process of scaling the measured FRF of torque by the motor controller based on the ideal DMD pulse height (the exact scaling can depend on the on / off pulse or 1-level / 2-level pulse strategy). The scaling process can be a time domain convolution or a frequency domain multiplication of the measured FRF with the expected pulses at different torque levels.

[0074] In such a process, NVH levels are estimated for different pulse frequencies and different motor torque levels. These estimated values ​​are then compared to calibrable thresholds for each noise / vibration measurement location (e.g., based on determined OEM targets). In this way, all frequency options for points that violate any threshold can be eliminated.

[0075] In such an embodiment, assuming that lower frequency pulses are more efficient for DMD operation, the lowest frequency pulse acceptable to NVH may be selected. If the lowest frequency is not necessarily the most efficient, another embodiment may combine the results with a table of efficiency as a function of pulse frequency, and the most efficient frequency acceptable to NVH may be selected based on that information.

[0076] The response can then continue to be monitored after the initial calibration to determine if further adjustments are needed. For example, the operating response and DMD and motor parameters (e.g., the same NVH parameters measured above, torque, pulse frequency, high and low pulse levels, motor speed, vehicle speed, etc.) can be remeasured.

[0077] This information can be used for further adjustments to fine tune the frequency selection calibration based on the operating response at different speeds and / or loads. In this way, the long-term NVH evolution for diagnostic data collection purposes can continue to be monitored and used to fine tune the calibration, and can be done during normal operation of the motor without the need for any specialized tools or equipment.

[0078] Therefore, these calibration implementations allow large-scale deployment of DMD with minimal NVH calibration effort. No additional sensors and excitation sources are required. The method is self-contained in the DMD software and utilizes typical production hardware.

[0079] Figure 2 is a diagram illustrating a pulse drive signal for a motor that may be used with embodiments of the present disclosure. Figure 2 An example of pulsed motor operation 222 is shown. In this particular example, the desired motor torque is 10 Nm, but the most efficient torque output by the currently operating motor speed is 50 Nm. Conceptually, the motor can be driven to deliver a net torque of 10 Nm 221 by having the motor deliver 50 Nm of torque 20% of the time and then delivering no (zero) torque the remaining 80% of the time. Since the motor operates more efficiently when delivering 50 Nm than when it is delivering 10 Nm, the overall efficiency of the motor can be improved by pulsing the motor operation in the manner described. Figure 2 In the example shown, the motor produces a machine output (referenced as 224) of 50 Nm during a period of 1 time unit out of every 5 time units, and then the motor is controlled to produce zero torque during the middle 4 time units.

[0080] As long as the required motor output does not exceed 50Nm, theoretically only changing the duty cycle of the motor running at 50Nm can meet the required machine output. For example, if the required motor output changes to 20Nm, the duty cycle of the motor running at 50Nm can be increased to 40%; if the required motor output changes to 40Nm, the duty cycle can be increased to 80%; if the required motor output changes to 5Nm, the duty cycle can be reduced to 10%, etc. More generally, pulse motors can potentially be used any time the desired motor torque drops below maximum efficiency.

[0081] As mentioned above, in some embodiments, the waveform frequency can be changed. In this case, the waveform period will also change. This will allow the controller to have a very sensitive, high-fidelity feedback response.

[0082] For example, the scale of the time units actually used may vary widely based on the size, nature, and design requirements of any particular system. In practice, when the motor switches from the "torque on" to the "low torque" state relatively quickly to achieve a specified duty cycle, the fact that the motor actually switches back and forth between these states may not materially degrade the performance of the motor from an operational perspective. In some embodiments, the time period scale of each on / off cycle is expected to be on the order of 100 μsec to 10 seconds (i.e., pulsed at a frequency in the range of 0.1 to 10,000 Hz), for example, in the range of 20 to 1000 Hz or 20 to 100 Hz.

[0083] The low torque portions of the waveform cycle can conceptually be considered to be shutting down the motor, although in many cases the motor may not actually be shut down during these time periods, or may only be shut down for portions of the "low torque" interval.

[0084] Figure 3 is a flow chart illustrating a motor control scheme according to an embodiment of the present disclosure. Figure 3 It is shown that the machine controller (e.g., Figure 1 The control process performed by the power supply / receiver (130) is performed by the machine controller (110) so that the motor (160) effectively delivers the required torque. To simplify the discussion, an embodiment in which the motor (160) is used as a motor is described. In this arrangement, the power supply / receiver (130) is used as a power source, and the machine controller (110) is used as a motor controller.

[0085] Initially, the motor controller (110) receives the currently requested motor output (113) and any required motor state information, such as the current motor speed (164), as indicated by block 371. The motor controller (110) then determines whether the requested output is within the pulse control range, as indicated by decision block 372. This determination may be made in any desired manner.

[0086] For example, in some embodiments, a lookup table (115) or other suitable data structure may be used to determine whether pulse control is appropriate. In some embodiments, a simple lookup table may identify the maximum torque levels at which pulse control is appropriate for various motor speeds. In such embodiments, the current motor speed may be used as an index into the lookup table to obtain the maximum torque level at which pulse control is appropriate under the current operating conditions. The retrieved maximum torque value may then be compared to the requested torque to determine whether the requested output is within the pulse control range.

[0087] In other implementations, the lookup table may provide additional information based on current operating conditions, such as a desired duty cycle for pulsed operation. In one such implementation, the motor speed and torque request may be used as indices into a lookup table, where each entry in the lookup table indicates a desired duty cycle, and when the actual torque and / or motor speed is between the index values ​​represented in the table, interpolation is used to determine the operating duty cycle.

[0088] If for any reason the requested torque / current operating conditions are outside the pulse control range, conventional (i.e., continuous / non-pulsed) motor control is used, as indicated by the "no" branch from block 372. Thus, pulsing is not used, and the power converter is directed to deliver power to the motor at a level appropriate to drive the motor, thereby delivering the requested output in a conventional manner, as indicated by block 374.

[0089] Conversely, when the requested torque / current operating conditions are within the pulse control range, pulse control is used, as indicated by the "yes" branch from block 372. In this embodiment, the motor controller will direct the power converter to deliver power to the motor in a pulsed manner.

[0090] During the "on" pulse, the power converter is directed to deliver power at a preferred output level, which is typically (but not necessarily) at or near the maximum efficiency operating level for the current motor speed. During the "off" pulse, the motor ideally outputs zero torque. In some embodiments, the timing of the pulses is controlled by a pulse controller.

[0091] To facilitate pulse operation, the motor controller determines the desired output level at box 375 and the desired duty cycle at box 376 for pulse operation at the current motor speed (which is preferably at or near the system's maximum efficiency energy conversion output level at the current motor speed, but other efficiency levels may be used as appropriate). Then, at box 378, the motor controller and pulse controller direct the power converter to implement the desired duty cycle at the specified power level.

[0092] Conceptually, this can be accomplished by effectively turning the power on and off at a relatively high frequency, so that the portion of the time power is supplied to the motor corresponds to the desired duty cycle, and the power level corresponds to the preferred output level. In some embodiments, the "off" portion of the duty cycle can be implemented by directing the power controller / converter to drive the motor to deliver zero torque.

[0093] The frequency of the power pulses is preferably determined by a machine controller or pulse controller. In some embodiments, the pulse frequency may be fixed for all operation of the motor, while in other embodiments it may vary based on operating conditions such as motor speed, torque demand, etc. For example, in some embodiments, the pulse frequency may be determined by using a lookup table.

[0094] In such an embodiment, an appropriate index (such as motor speed, torque demand, etc.) may be used to look up the appropriate pulse frequency for the current motor operating conditions. In other embodiments, the pulse frequency is not necessarily fixed for any given operating condition and may vary as directed by the pulse controller. In some specific embodiments, at least in some operating regions of the motor, the pulse frequency may vary proportionally as a function of the motor speed.

[0095] Further, in order to determine the desired pulse level 375 and the desired duty cycle 376, multiple torque values ​​need to be determined during motor operation. This can be accomplished using the integer multiple based torque averaging method described herein. By using the disclosed method, at 378, pulse power delivery will be at a more precise power level and / or duty cycle than previously achievable. It should be noted that, while representing a potential power estimation method, the details of the pulses may involve multiple solutions to adequately address vibration and / or noise while delivering optimal efficiency.

[0096] Three embodiments are provided below that describe various concepts of the present disclosure. For example, in one vehicle embodiment, the vehicle includes a motor controller having a processor and a memory and instructions stored in the memory and executable by the processor to identify a vehicle and / or motor frequency response during vehicle operation and select a dynamic motor drive pulse frequency based in part on the identified frequency response using the motor and a dynamic motor drive converter.

[0097] In some such embodiments, the dynamic motor drive converter is an inverter and outputs a current waveform having an excitation frequency based on the identified frequency response. For example, the output current waveform having the excitation frequency is one of the following forms: steady state, random, periodic, or transient.

[0098] In various implementations, identifying vehicle and / or motor frequency responses during vehicle operation includes collecting measured noise and vibration sensor data using at least one onboard sensor in the vehicle. For example, the data may be collected from a microphone for Bluetooth communications with a vehicle occupant, a microphone for wireless communications with a vehicle occupant, a microphone used by a vehicle occupant with an entertainment system, a microphone used by a vehicle occupant with a navigation system, and / or an accelerometer for collision detection.

[0099] In some embodiments, the measured noise and vibration sensor data can be processed to calculate a frequency response function due to source excitation. For example, this can be achieved by executing instructions that are executed to detect peaks in the calculated frequency response function to identify resonance, or compare the frequency response to a calibratable threshold to determine the peak magnitude that needs to be mitigated. In some implementations, if it is determined that the peak magnitude needs to be mitigated, instructions are executed to change the dynamic motor drive pulse frequency.

[0100] In another embodiment, for a motor controller in a vehicle, the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to calibrate a frequency selection or avoidance table, wherein the calibration includes scaling a frequency response function of at least one measure of torque based on an ideal dynamic motor drive pulse height. The embodiment also includes instructions for estimating a number of noise, vibration, harshness (NVH) levels at different locations on the vehicle for different pulse frequencies and different levels of motor torque.

[0101] In this embodiment, the estimated NVH levels are compared to at least one calibratable threshold for each different position, a determination is made as to which of the estimated NVH levels meet or exceed the threshold, and a motor pulse frequency is selected that is acceptable to NVH, assuming that lower frequency pulses are more effective for dynamic motor drive operation. In some implementations, the lowest frequency of motor pulses that is acceptable to NVH may be selected.

[0102] For example, selecting a motor pulse frequency that is acceptable to NVH may include combining the selection result with data such as an efficiency table as a function of pulse frequency. In this configuration, the most efficient frequency that is acceptable to NVH may be selected.

[0103] In some embodiments, at least one measured frequency response function of torque based on an ideal dynamic motor drive pulse height is implemented by time domain convolution. For example, scaling can also be implemented by frequency domain multiplication of one of the measured frequency response functions having a frequency domain representation of the waveform with the expected pulse frequency at different torque levels.

[0104] In another example embodiment, a motor controller in a vehicle has a processor and a memory and instructions stored in the memory and executable by the processor to monitor operational NVH response after an initial calibration, wherein the initial calibration includes calibrating a frequency selection or avoidance table, wherein the calibration includes scaling a frequency response function of at least one measurement of torque based on an ideal dynamic motor drive pulse height, measuring the NVH operational response and one or more dynamic motor drive or motor parameters, and adjusting the frequency selection calibration based on the NVH operational response measured at different speeds or torque loads. In various such embodiments, the instructions are executed to continue monitoring long-term NVH evolution for diagnostic data collection purposes, and wherein the diagnostic data is stored in the memory.

[0105] In some embodiments, one or more dynamic motor drive or motor parameters are selected from parameters including: torque, pulse frequency, high level pulses, low level pulses, motor speed, and vehicle speed. The waveform period may also vary as a function of the rotational speed of the motor.

[0106] For example, the first output level may be the most efficient torque level for the motor at its given speed, and the second output level may be 0% torque. In some embodiments, during pulsed operation of the motor, the motor is shut off for at least a portion of the time that the motor outputs zero torque.

[0107] In various embodiments, the time period between the start of consecutive first output level pulses can be defined as a waveform period. For example, the waveform period can vary during motor operation. These embodiments can improve motor performance and / or system efficiency by providing more accurate calibration and verification of power usage.

[0108] Figure 4 is an equivalent circuit model (ECM) that can be used to estimate battery system dynamic and pulse power losses and can be used with embodiments of the present disclosure. Figure 4In the power system depicted at 440 in FIG. 1 , a battery (e.g., 448) is generally approximated as a voltage source 441, represented as an open circuit voltage (OCV or V_OC) 444, followed by a series resistor 442 and one or more parallel resistor-capacitor (RC) branches 443, such as Figure 4 The number of RC branches is selected to capture the desired dynamic behavior, with 2-4 branches typically being sufficient. Additional components of the ECM (e.g., 446, 447) may be included to capture the resistive, capacitive, and inductive behavior in the high voltage distribution system (DC bus) and auxiliary equipment.

[0109] OCV, resistance, capacitance, and inductance are usually determined empirically under strictly controlled conditions on a test bench with well-known test procedures. The voltage hysteresis between charge and discharge is also usually included. Optionally, methods exist to calculate or adjust these parameters using more advanced techniques during routine operation. Alternatively, high-fidelity simulations can also be used instead of bench tests.

[0110] Figure 5 are examples of sample ECM model parameters that may be used with embodiments of the present disclosure. Table 1 shows examples of cell ECM parameters for a commercial 18650 cell (LG INR18650MJ1). These also illustrate functions of cell temperature and cell state of health (SOH). While single cell characterization can be extended to multi-cell modules or packs, it may be valuable to directly characterize the pack ECM to capture the effects of contact resistance and wiring / bus bars.

[0111] Once the ECM parameters are known, the pulse efficiency impact can be estimated analytically. For example, determining these parameters can be done where the cell is at a given OCV and average current The average power delivered Given by the following equation:

[0112]

[0113] Where R eq is the equivalent series resistance, and D is the pulse current duty cycle (assuming a standard pulse width modulated signal). Therefore, the equivalent series resistance R eq It is an important ECM parameter required to calculate standard or continuous power and pulsed power as well as potential pulsed power loss.

[0114] The impedance Z of the four RC branches ECMZ as a function of the sinusoidal current of frequency f is defined as:

[0115]

[0116] A capacitor or capacitor bank C can be added at the output of the batteryout , to mitigate the losses caused by higher current pulses. In this case, the updated impedance Z will be:

[0117]

[0118] C out It will act as a reactive power compensator and improve the total power loss. out is not part of the battery itself and does not affect the algorithm, so in the following calculations we will focus on the battery itself and ignore C out .

[0119] The resistors and capacitors used in the above equations are Figure 5 The table of FIG. 1 shows the charge state and voltage at 551 at 552 and 553. The variable j is an imaginary unit representing a complex number.

[0120] Figure 6 is an example of a pulse-width modulated (PWM) square wave and its dimensional elements that can be used with embodiments of the present disclosure. For a PWM signal such as Figure 6 As depicted in , the function I(t) can be approximated using the Fourier series expansion:

[0121]

[0122] Where α is the proportion of on time, i.e., duty cycle, A max is the pulse amplitude, ω is the angular frequency (in rad / s), t is time, and n is the number of harmonics considered. Other types of waveforms can be similarly parameterized and approximated.

[0123] The apparent power, S, can be obtained from the following equation, where the real power is given by the real component Re(S):

[0124]

[0125] The equivalent resistance is then calculated from the actual power using the standard resistance-power relationship:

[0126]

[0127] Figure 7 The trend of equivalent resistance over a range of duty cycles that can be obtained using embodiments of the present disclosure is shown at a given frequency and average current (C-rate). Based on these relationships, the pulse power loss 754 at different duty cycle values ​​755 can be calculated based on the ratio of the average power under pulsed conditions to the non-pulsed or DC power at the same average current. Figure 8Example loss plots for a given OCV, frequency, and temperature are shown in . The losses increase rapidly with increasing current (C-rate) and duty cycle.

[0128] Similar maps can be created for pulse frequency, battery temperature, SOC, and SOH. This loss factor can be used in DMD system optimization to select waveform parameters that deliver an overall positive efficiency gain. The next section discusses the algorithm that achieves this goal.

[0129]

[0130] Figure 8 is a graphical representation of the power loss of pulse current at average current rate (C-rate) and pulse duty cycle using an embodiment of the present disclosure. System optimization needs to be combined with DMD gain and battery power loss estimates for the motor / inverter system. NVH constraints are also typically part of the optimization. An overview of the method for adjusting the duty cycle parameters is shown below:

[0131] 1. Enter the current motor speed and drive torque request.

[0132] 2. Determine the DMD waveform parameters (frequency, duty cycle, amplitude) for maximum motor / inverter efficiency based on a model or lookup table.

[0133] 3. Determine the DMD efficiency gain compared to standard operation based on model type or lookup table.

[0134] 4. Estimate the average current on the DC bus based on the voltage (eg, bus voltage).

[0135] 5. Calculate the equivalent battery resistance for the selected DMD waveform parameters, battery SOC, SOH and temperature.

[0136] 6. Calculate the battery pulse power loss for selected DMD waveform parameters, battery SOC, SOH and temperature.

[0137] 7. Estimate the overall system gain.

[0138] 8. If the system gain is negative (loss), increase the pulse duty cycle and loop back to step 3.

[0139] 9. If the system gain is positive and the gradient is also positive (or first iteration), then reduce the pulse duty cycle and loop back to step 3.

[0140] 10. If the system gain is positive and the gradient is zero or negative, select the previous pulse duty cycle and exit the loop.

[0141] Depending on the control parameters, NVH constraints may enter various parts of this optimization loop. For example, if the pulse frequency is only used to mitigate vibration, the motor-battery duty cycle optimization can be performed first, and then the acceptable frequency for this torque amplitude can be determined. In terms of the above method, this step will be the last additional step. If multiple parameters that affect efficiency and NVH need to be optimized simultaneously, NVH constraints should be considered in the loop (for example, when determining motor-inverter gains or overall system gains).

[0142] As needed, other parameters can be included in the optimization and loop conditions (e.g., gradients) can be set based on efficiency trends associated with each parameter. The above method is a conceptual example to illustrate the general idea. In practice, the optimization process should be selected to match the characteristics of the underlying function and accelerate convergence. For some of them, it may be beneficial to create approximate mathematical functions and derivatives by mathematical methods known in the art.

[0143] Depending on the parameters considered and the computational power available to the onboard computer, the optimization can be performed online or offline. In some embodiments, the offline optimization can use advanced machine learning methods to capture many inputs and nonlinear effects.

[0144] These machine learning models also come with a greater computational burden that needs to be justified and managed. Online optimization may have to be simpler in terms of degrees of freedom. At the same time, this will provide greater flexibility to independently modify subcomponents such as motor / inverter efficiency and battery power losses. In addition, online optimization can be used for predictive control and trajectory optimization.

[0145] Given the additional complexity of DMD control and system impacts, both the base model and optimization can benefit from more advanced methods than those already used. This may become even more critical if components other than the motor / inverter and battery are included, such as high voltage distribution systems, auxiliary equipment, etc.

[0146] An example of such an alternative application is capturing battery degradation and changes in internal resistance over time. In this case, online training algorithms for machine learning and artificial intelligence can provide a mechanism for self-calibration of the battery equivalent circuit model.

[0147] Models based on reduced-order physics are also more feasible for deployment in embedded systems with improved computing power. When properly designed and calibrated, these alternative implementations can provide a more generalized approach to capture the complex behavior and evolution of Li-ion batteries under pulse conditions.

[0148] Three embodiments of various concepts of the present disclosure are provided below. For example, in a motor controller in a vehicle, the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to receive a current motor speed and a driver torque request, determine a maximum motor or inverter efficiency, and determine a dynamic motor drive (DMD) efficiency gain compared to standard operation. The embodiment also includes instructions for estimating average current, calculating equivalent battery resistance, calculating pulse power loss, estimating overall system gain, and determining whether the system gain is negative or positive and adjusting the pulse duty cycle differently based on the negative or positive determination. In some implementations, the DMD waveform parameters are selected from: frequency, duty cycle, and amplitude.

[0149] In some implementations, the maximum motor or inverter efficiency may be determined based on a model type or data in a lookup table.The dynamic motor drive efficiency gain compared to standard operation may also be determined based on a motor model type or data in a lookup table.

[0150] In various implementations, for example, the average current can be estimated based on the bus voltage measured on the DC bus. The equivalent battery resistance can be calculated for one or more selected DMD waveform parameters. The equivalent battery resistance can also be calculated for battery state of charge (SOC), state of health (SOH), and / or temperature.

[0151] In another example embodiment, a motor controller in a vehicle has a processor and a memory and instructions stored in the memory and executable by the processor to receive a current motor speed and a driver torque request, determine a maximum motor or inverter efficiency, and determine a dynamic motor drive (DMD) efficiency gain compared to standard operation. The embodiment includes instructions for estimating an average current, calculating an equivalent battery resistance, calculating a pulse power loss, estimating an overall system gain based on the calculated equivalent battery resistance and pulse power loss, and determining whether the system gain is negative or positive and adjusting the pulse duty cycle differently based on a negative or positive determination.

[0152] In some implementations, for example, pulse power loss can be calculated for one or more selected DMD waveform parameters, state of health (SOH), battery state of charge (SOC), and / or temperature.

[0153] In another example embodiment, a motor controller in a vehicle includes a processor and a memory and instructions stored in the memory and executable by the processor to receive a current motor speed and a driver torque request, determine a maximum motor or inverter efficiency, and determine a dynamic motor drive (DMD) efficiency gain compared to standard operation. The embodiment also includes instructions for estimating average current, calculating equivalent battery resistance, calculating pulse power losses, estimating overall system gain, and determining whether the system gain is negative or positive and adjusting the pulse duty cycle differently based on the negative or positive determination.

[0154] In some embodiments, if the system gain is negative, the pulse duty cycle is increased and looped back to determine the DMD efficiency gain compared to standard operation. Further, if the system gain is positive and the gradient of the iterative gain is also positive, the pulse duty cycle is decreased and looped back to determine the DMD efficiency gain compared to standard operation. Moreover, if the system gain is positive and the gradient is zero or negative, a previous pulse duty cycle can be selected. As with the previous examples, embodiments such as these can improve motor performance and / or system efficiency by providing more accurate calibration and verification of power usage.

[0155] Fig. 9A is an example of a speed of a motor at which embodiments of the present disclosure may benefit. Fig. 9B is an example of the amount of torque of an electric machine from which embodiments of the present disclosure may benefit. Fig. 9C are examples of normalization schemes for processing torque variations during a sampling period according to an embodiment of the present disclosure. In these combined examples, a method of normalizing torque variations is described.

[0156] The following provides a method embodiment according to the present disclosure, and provides Figures 9A-9C The method shown below depicts an embodiment where a comparison is made between parameters of DMD mode and continuous mode. Figures 9A-9C The numbers on the top represent the component numbers provided below (for example, Fig. 9A 1 corresponds to element #1 below, "in preheating state, ..."). This method provides:

[0157] 1. In the preheating state, enter the torque window and set the basic speed value.

[0158] 2. If in DMD state, mark as "stable" and stay within the torque / speed window for X seconds (about 3).

[0159] 3. Record the DMD battery terminal voltage and / or current (V / I) for Y seconds (about 1.5) and calculate the power.

[0160] 4. Switch to continuous mode and wait for Z seconds (about 1).

[0161] 5. Record the battery terminal V / I in continuous mode for Y seconds and calculate the power.

[0162] 6. Resume normal DMD operation.

[0163] 7. Determine and apply power and / or current normalization factors, and then calculate the average power and / or current.

[0164] 8. Calculate the expected gain in power and / or current from a pre-calibrated motor map and / or look-up table (LUT).

[0165] 9. Compare the DMD gain to the expected gain from the map / LUT.

[0166] 10. If the DMD gain is below some threshold expected, then take action. For example:

[0167] 1. At a given motor speed / temperature / bus voltage, DMDs with torque ≥ reference torque are prohibited

[0168] 2. Throw an error.

[0169] 3. Change the DMD "opening" torque.

[0170] 11. If the method aborts at step 4, the controller may save the data of steps 1-3 and complete steps 5+ if the torque / speed window is later re-entered (as long as the motor temperature and voltage are similar enough).

[0171] Fig.10 is another description of a DMD continuous method embodiment according to the present disclosure. The method shown below depicts an embodiment in which a comparison is made between parameters of the DMD mode and the continuous mode.

[0172] The method 1080 provides: reading input data at 1081. For example, the input data may include motor speed, torque, voltage, battery SOC, SOH, and / or temperature. The data may be obtained from sensors associated with the motor and / or the vehicle in which the motor is operating, from a memory (such as a lookup table), and / or from data input into the system from a source or computing device external to the system.

[0173] The method also includes checking to determine if the motor is in a preheating state 1082, and if the speed and / or torque is stable in DMD mode at 1083. If either of these is "no", the method returns to 1082. If "yes", at least one of the battery voltage and / or current is recorded during the time period at 1084.

[0174] Then, at 1085, the motor is switched to continuous mode to collect continuous mode data. Then, at 1086, the motor is checked to determine if the speed and / or torque is stable in continuous mode. If the determination is "no", the method returns to 1081. If "yes", at 1087, at least one of the battery voltage and / or current for the time period is recorded. Then, at 1088, the motor can be returned to normal operation.

[0175] In some embodiments, DMD mode and continuous mode data can be recorded using corresponding time lengths. This can make it easier to compare data sets.

[0176] Once this data is recorded, at 1089 the motor controller can calculate and apply a normalization factor such as Figure 7 and 9A At 1090, the data can also be used to calculate the average power and / or current value and the DMD gain for the recording period based on a comparison of the DMD data and the continuous data.

[0177] This embodiment may be beneficial because the DMD gains are based on two data sets acquired during actual operation of the motor and may make the analysis more accurate. Also, it may allow for better fine tuning because subsequent data sets may be acquired after adjustments have been made to previous data comparisons.

[0178] Further, in the method, at 1091, an expected DMD gain may be calculated from data stored in a memory, such as in one or more lookup tables (LUTS). Then, at 1092, the actual gain may be compared to the expected gain to determine whether the actual gain is acceptable. For example, it may be determined whether the actual DMD gain exceeds a threshold based on the expected gain value.

[0179] If it is acceptable, the method returns to 1081. If it is not acceptable, the motor controller may take action 1093 to increase the DMD gain. For example, at 1094, the controller may change the DMD calibration, give an error indication, and / or disable the DMD for torques greater than or equal to the reference torque at a given motor speed, temperature, and / or voltage, among other actions that may be taken.

[0180] Fig.11 is another method embodiment according to the present disclosure. The illustrated method depicts an embodiment in which only DMD mode parameters are utilized.

[0181] This method is similar to Fig.10, but with some differences, which will be discussed below. The method 1195 similarly provides: reading input data at 1181. As described above, for example, the input data may include motor speed, torque, voltage, battery SOC, SOH, and / or temperature. The data may be obtained from sensors associated with the motor and / or the vehicle in which the motor is operating, from a memory (such as a lookup table), and / or from data input into the system from a source or computing device external to the system.

[0182] The method also includes checking to determine if the motor is in a preheating state 1182, and if the speed and / or torque is stable in DMD mode at 1183. If either of these is "no", the method returns to 1182. If "yes", at least one of the battery voltage and / or current is recorded during the time period at 1184.

[0183] However, in this method, the motor controller calculates and applies a normalization factor at 1189, such as Figure 7 and 9A -9C, instead of switching to continuous mode to collect continuous mode data, data collection in continuous mode is skipped. Fig.10 As shown, at 1190, this data may also be used to calculate average power and / or current values ​​and DMD gain for the recording period based on a comparison of the DMD data.

[0184] Further, in the method, at 1191, the expected DMD power and / or current can be calculated from data stored in a memory, such as in one or more lookup tables (LUTS). Then, at 1192, the actual power / current can be compared with the expected power / current to determine whether the actual power / current is acceptable. As in the above embodiment, for example, it can be determined whether the actual DMD power / current exceeds a threshold based on the expected power / current value.

[0185] If it is acceptable, the method returns to 1181. If it is not acceptable, the motor controller may take action 1193 to increase the DMD gain. For example, at 1194, the controller may change the DMD calibration, give an error indication, and / or disable the DMD for torques greater than or equal to the reference torque at a given motor speed, temperature, and / or voltage, among other actions that may be taken.

[0186] In addition, an example of an alternative implementation using only DMD mode parameters is provided below, which is similar to Fig.11 As shown, but including some differences, and citing some example components and values, these components and values ​​may be helpful in understanding the implementation of the present disclosure. In this method, the process includes:

[0187] 1. In the preheating state, enter the torque window and set the basic speed value.

[0188] 2. If in DMD state, mark as "stable" and stay within the torque / speed window for X seconds (about 3).

[0189] 3. Record the V / I at the DMD battery terminal for Y seconds (about 1.5) and calculate the power.

[0190] 4. Apply the power and / or current normalization factor and then calculate the average power and / or current.

[0191] 5. Calculate expected power / current from pre-calibrated maps / LUTs.

[0192] 6. Compare the DMD power and / or current to the expected values ​​from the map / LUT.

[0193] 7. If the DMD power / current is above some threshold expected, then take action. For example:

[0194] 1. At a given motor speed / temperature / voltage, DMDs with torque ≥ reference torque are prohibited.

[0195] 2. Throw an error.

[0196] 3. Change the DMD "opening" torque.

[0197] Three implementations are provided below that describe various concepts of the present disclosure. For example, in a motor controller in a vehicle, the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to receive motor operating data including at least one of the following: motor speed, torque, voltage, battery state of charge, health state, and motor temperature. The controller includes instructions stored in the memory and executable by the processor to determine whether the motor is in a preheated state, initiate a torque activation window, set a base speed value, and determine whether the motor is in a dynamic motor drive (DMD) mode and remains in a torque activation window for a first time period.

[0198] This embodiment also includes instructions for recording one or more of the DMD battery terminal voltage and the DMD battery terminal current for a second time period, then calculating the DMD power, switching to continuous mode, waiting for a third time period, recording one or more of the continuous mode battery terminal voltage or the continuous mode battery terminal current for a fourth time period, then calculating the continuous power, and resuming normal DMD operation process.

[0199] In some such embodiments, the controller includes instructions stored in the memory and executable by the processor to: compare the measured DMD torque / speed with the reference torque / speed to determine a normalization factor, and apply the normalization factor to the operating data to calculate the average power and / or current. In addition, the controller may include instructions stored in the memory and executable by the processor to: calculate an expected gain in power and / or current based on the operating data, and compare the DMD gain with the expected gain or threshold.

[0200] If the DMD gain is below an expected gain or threshold, the motor controller may, for example, initiate an action to modify the DMD process, may inhibit DMD activation for torques greater than or equal to a reference torque at a particular motor speed, or may inhibit DMD activation for torques greater than or equal to a reference torque at a particular temperature. For example, the temperature may be obtained from an internal sensor within the motor or the oil / coolant temperature of the motor.

[0201] Further, if the DMD gain is below a threshold, the motor controller may prohibit DMD activation at a torque greater than or equal to a reference torque at a specific voltage. Also, in some implementations, if the DMD gain is below a threshold, the motor controller may initiate an error indication, or may initiate a change to a DMD "on" torque process value.

[0202] In some implementations, for example, the first time period can be at least two seconds, the second time period can be at least one second, the third time period can be at least one second, and / or the second time period can be the same as the fourth time period. Also, in various implementations, for example, setting the base speed value can be based on determining whether the torque is at a stable value at a particular speed, and if so, setting the speed as the base speed value.

[0203] In another example embodiment, a motor controller in a vehicle has a processor and a memory and instructions stored in the memory and executable by the processor to receive motor operating data including at least one of the following: motor speed, torque, voltage, battery state of charge, state of health, and motor temperature. The controller in the vehicle has a processor and a memory and instructions stored in the memory and executable by the processor to determine whether the motor is in a preheated state, initiate a torque activation window, set a base speed value, determine whether the motor is in a dynamic motor drive (DMD) mode - if so, remain within the torque activation window, record multiple measurements of one or more of the DMD battery terminal voltage and the DMD battery terminal current during the torque activation window, then calculate the DMD power for each measurement, determine a normalization factor from a comparison of the measured speed / torque value with the base speed / torque value, and apply the normalization factor to the operating data to calculate the average power and / or current.

[0204] In various embodiments, the controller includes instructions stored in a memory and executable by a processor to: calculate an expected power and / or current based on operating data and compare the DMD power and / or current to the expected power and / or current, or calculate the DMD average power and / or current and compare the DMD power and / or current to a threshold.

[0205] In the following example implementation, a motor controller in a vehicle includes a processor and a memory and instructions stored in the memory and executable by the processor to receive motor operation data including at least one of the following: motor speed, torque, voltage, battery state of charge, state of health, and motor temperature. The controller in the vehicle includes a processor and a memory and instructions stored in the memory and executable by the processor to determine whether the motor is in a preheated state, initiate a torque activation window that initiates a dynamic motor drive (DMD) mode, set a base speed value, evaluate whether operation is maintained within the torque activation window for a first time period, and record one or more of a DMD battery terminal voltage and a DMD battery terminal current for a second time period, and then calculate the DMD power.

[0206] The embodiment also includes instructions to: switch to continuous mode, wait for a third time period, record one or more of the continuous mode battery terminal voltage and the continuous mode battery terminal current for a fourth time period, then calculate continuous power, compare the measured speed / torque value with the base speed / torque value to determine a normalization factor and apply the normalization factor to the operating data to calculate average power and / or current, calculate an expected gain in power and / or current based on the operating data and compare the DMD gain to an expected gain or threshold, and wherein if the DMD gain is less than the expected gain or threshold, the motor controller initiates an action to modify the DMD process. In various embodiments, the expected value can be determined by testing on similar machines or the particular machine.

[0207] In such an embodiment, if the DMD gain is below a threshold, the motor controller may, for example, initiate an error indication and / or initiate a change to the DMD "on" torque process value.

[0208] Embodiments of the present disclosure utilize the techniques disclosed herein to calibrate a vehicle's DMD system. They can be used to set up an initial calibration, and can also be used to perform diagnostic checks on the calibration during the life of the vehicle.

[0209] Dynamic calibration and checking the DMD during vehicle use can be very beneficial in some applications when considering that vehicle dynamics vary based on road conditions, vehicle load, etc. For example, on a noisy road, it is understood that the DMD gain can be pushed by selecting a calibration that results in higher NVH, but still low enough that the noisy road masks the increase in NVH caused by the DMD modulation. This can be achieved dynamically by pushing the DMD gain to the highest value allowed by the current vehicle NVH.

[0210] This may be done by having at least one NVH sensor to detect current NVH for use in pre-selecting NVH calibration, feed forward or as feedback for selecting NVH calibration based on current conditions.During vehicle use, sensor data may be sampled periodically.

[0211] The data may be analyzed periodically during vehicle use to determine whether adjustments may be made to increase or decrease the DMD effect to be close to, but equal to, or below an NVH threshold based on data analyzed by at least one NVH sensor.

[0212] Embodiments of the present disclosure provide methods, systems, and apparatus for motor drive calibration, verification, and efficiency improvement. These embodiments may also improve motor performance and / or system efficiency by providing more accurate calibration and verification of power usage.

[0213] Although specific embodiments have been shown and described herein, those of ordinary skill in the art will appreciate that any arrangement calculated to achieve the same technique may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of the various embodiments of the disclosure.

[0214] It should be understood that the above description is carried out in an illustrative manner, rather than a limiting manner. After reading the above description, combinations of the above embodiments and other embodiments not specifically described herein will be apparent to those skilled in the art.

[0215] The scope of the various embodiments of the present disclosure includes any other applications using the above structures and methods. Therefore, the scope of the various embodiments of the present disclosure should be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled.

[0216] In the above detailed description, various features are grouped together in the example embodiments shown in the drawings for the purpose of simplifying the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the disclosure require more features than are expressly recited in each claim.

[0217] Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment.Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.

Claims

1. A motor controller in a vehicle, wherein the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to: identifying vehicle and / or motor frequency responses during operation of said vehicle; and The motor and a dynamic motor drive converter are used to select a dynamic motor drive pulse frequency based in part on the identified frequency response. 2 . The motor controller of claim 1 , wherein the dynamic motor drive converter is an inverter and outputs a current waveform having an excitation frequency based on the identified frequency response.

3. The motor controller of claim 2, wherein the output current waveform having the excitation frequency is in the form of one of the following: steady state, random, periodic, or transient. 4 . The motor controller of claim 1 , wherein identifying the vehicle and / or motor frequency response during operation of the vehicle comprises collecting measured noise and vibration sensor data using at least one onboard sensor in the vehicle.

5. The motor controller of claim 4 , wherein the at least one onboard sensor in the vehicle is a microphone for Bluetooth communication with a vehicle passenger, a microphone for wireless communication with a vehicle passenger, a microphone for use with an entertainment system by a vehicle passenger, a microphone for use with a navigation system by a vehicle passenger, or an accelerometer for collision detection.

6. The motor controller of claim 1 , wherein identifying the vehicle and / or motor frequency response during operation of the vehicle comprises collecting measured noise and vibration sensor data using at least one onboard sensor in the vehicle and processing the sensor data to calculate a frequency response function due to source excitation.

7. The motor controller of claim 6, wherein the instructions are executable to detect peaks in the calculated frequency response function to identify resonance or to compare the frequency response to a calibratable threshold to determine peaks requiring magnitude mitigation.

8. The motor controller of claim 7, wherein if it is determined that the magnitude of the peak needs to be mitigated, the instructions are executed to change the dynamic motor drive pulse frequency.

9. A motor controller in a vehicle, wherein the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to: Calibration frequency selection or avoidance table; wherein the calibration comprises scaling a frequency response function of at least one measurement of torque based on an ideal dynamic motor drive pulse height; estimating a number of noise, vibration, harshness (NVH) levels at different locations on the vehicle for different pulse frequencies and different levels of motor torque; comparing the estimated NVH level to at least one calibratable threshold value for each of the different locations; determining which estimated NVH levels meet or exceed a threshold; and Assuming that lower frequency pulses are more efficient for dynamic motor drive operation, a motor pulse frequency is selected where NVH is acceptable.

10. A motor controller as claimed in claim 9, wherein the lowest frequency of motor pulses for which NVH is acceptable is selected on the assumption that the lower frequency pulses are more efficient for dynamic motor drive operation.

11. The motor controller of claim 9, wherein selecting a motor pulse frequency that is acceptable to NVH comprises combining the selection with a table of efficiency as a function of pulse frequency, and wherein the most efficient frequency that is acceptable to NVH is selected.

12. The motor controller of claim 9, wherein scaling the frequency response function of at least one measure of torque based on an ideal dynamic motor drive pulse height is accomplished by time domain convolution.

13. The motor controller of claim 9 wherein scaling of at least one measured frequency response function of torque based on an ideal dynamic motor drive pulse height is accomplished by frequency domain multiplying one of the measured frequency response functions having a frequency domain representation of a waveform by an expected pulse frequency for different torque levels.

14. A motor controller in a vehicle, wherein the motor controller has a processor and a memory and instructions stored in the memory and executable by the processor to: Monitor operational NVH response after initial calibration, which includes: Calibration frequency selection or avoidance table; wherein the calibration comprises scaling a frequency response function of at least one measurement of torque based on an ideal dynamic motor drive pulse height; measuring NVH operational response and one or more dynamic motor drive or motor parameters; and The frequency selection calibration is adjusted based on the NVH operating response measured at different speeds or torque loads. 15 . The motor controller of claim 14 , wherein the instructions are executable to continue monitoring long-term NVH evolution for diagnostic data collection purposes, and wherein the diagnostic data is stored in a memory.

16. The motor controller of claim 14, wherein the one or more dynamic motor drive or motor parameters are selected from the group consisting of: torque, pulse frequency, high level pulses, low level pulses, motor speed, and vehicle speed.

17. The motor controller of claim 14, wherein the waveform period varies as a function of the rotational speed of the motor.

18. The motor controller of claim 14, wherein the first output is the most efficient torque level for the motor at its given speed, and the second output level is 0% torque.

19. The motor controller of claim 14, wherein during pulsed operation of the motor, the motor is turned off for at least a portion of the time that the motor outputs zero torque.

20. The motor controller of claim 14, wherein a time period between the start of consecutive first output horizontal pulses is a waveform period, and the waveform period varies during operation of the motor.

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