Pulse motor control

Abstract

The motor is pulse controlled and more specifically one or more of the pulse frequency, the amplitude of the pulses and / or the duty cycle of the pulses are selectively adjusted to reduce noise, vibration and harshness (NVH) while maintaining a high level of operational efficiency.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Application No. 17 / 158,230, filed January 26, 2021, which is incorporated herein by reference. Background Technology

[0003] This application generally relates to pulse control of electric motors, and more specifically to selectively adjusting one or more of the pulse frequency, pulse amplitude, and / or pulse duty cycle to reduce noise, vibration, and harshness (NVH) while maintaining a high level of operating efficiency.

[0004] Electric motors and generators are structurally very similar. Both consist of a rotor and a stator with multiple poles. Most electric motors can operate as generators, and vice versa. When operating as an electric motor, electrical energy is converted into mechanical energy. When operating as a generator, mechanical energy is converted into electrical energy. Therefore, the term "electric motor" as used herein is intended to be understood broadly to refer to both electric motors and generators.

[0005] Electric motors are used in a wide variety of applications and typically need to operate under a wide range of loads. Because energy conversion efficiency can vary greatly depending on the measurable load, motors are sometimes operated at their peak efficiency, but are usually required to operate outside of their peak efficiency levels.

[0006] Pulsing is a known method for improving motor efficiency. Taking an electric motor as an example, output torque is generated when a pulse is applied, but no torque output is generated between pulses. As a general rule, the pulse amplitude (i.e., torque output) is selected to be in or near the motor's highest efficiency range, while the duty cycle (i.e., the percentage of time the motor is on and off) and / or frequency (i.e., the time interval between pulses) are selected such that the motor's total output meets the requested torque requirement while operating as efficiently and economically as possible.

[0007] While pulsed operation of motors improves efficiency and economy, it can also present some drawbacks. In particular, higher pulse amplitudes typically generate more noise, vibration, and harshness (NVH). Furthermore, excessively low pulse frequencies can also lead to excessive NVH. In many applications, such as the use of electric motors in electric and / or hybrid vehicles, excessive NVH is unacceptable.

[0008] Therefore, it is necessary to selectively adjust one or more of the frequency, amplitude, and / or duty cycle of the pulses used for motor pulse operation in order to reduce NVH while still maintaining a high level of operating efficiency and economy. Summary of the Invention

[0009] This invention relates to a system and method for adjusting the pulse frequency during pulsed operation of an electric motor in a vehicle to reduce noise, vibration, and harshness (NVH) while maintaining a high level of operating efficiency. Attached Figure Description

[0010] The invention and its advantages are best understood by referring to the following description taken in conjunction with the accompanying drawings, in which:

[0011] Figure 1 It is a representative torque / speed / efficiency curve that shows the energy conversion efficiency of a representative motor operating under different operating conditions.

[0012] Figure 2 It is a graph showing the pulse drive signal used for the motor.

[0013] Figure 3A It is a graphical representation of the waveform of a continuous three-phase AC drive signal.

[0014] Figure 3B and Figure 3C It is generated and Figure 3A Two different examples of continuous waveforms of the same torque output pulse three-phase AC waveform, both with a 50% duty cycle, but with different frequencies.

[0015] Figure 4 A representative table of a non-exclusive embodiment of the invention is shown, which provides pulse frequencies for different combinations of torque and / or motor speed.

[0016] Figure 5A This is a functional block diagram illustrating a motor controller according to a non-exclusive embodiment of the present invention.

[0017] Figure 5B This is a non-exhaustive list of possible inputs that can be provided to the motor controller according to a non-exclusive embodiment of the present invention.

[0018] Figure 6 This is a flowchart illustrating the steps implemented by a motor controller according to a non-exclusive embodiment of the present invention.

[0019] Figure 7 This is a diagram illustrating real-time feedback for adjusting the pulse frequency of a motor according to a non-exclusive embodiment of the present invention.

[0020] In the accompanying drawings, the same reference numerals are sometimes used to designate the same structural elements. It should also be understood that the depictions in the drawings are illustrative rather than to scale. Detailed Implementation

[0021] This disclosure generally relates to pulse control of motors (e.g., electric motors and generators) to improve the energy conversion efficiency of the motor when operating conditions permit. More specifically, under selected operating conditions, pulses are intermittently applied to the motor to make it operate at a higher efficiency level than conventional continuous motor control, thereby delivering the desired average torque output in a more energy-efficient manner than previously possible.

[0022] The applicant has filed numerous applications relating to pulse control of motors, including U.S. Provisional Patent Application No. 62 / 644,912, filed March 19, 2018; U.S. Provisional Patent Application No. 62 / 810,861, filed February 26, 2019; U.S. Provisional Application No. 62 / 819,097, filed March 15, 2019; and U.S. Provisional Patent Application No. 62 / 658,739, filed April 17, 2018. Each of the above-listed applications is incorporated herein by reference for all purposes.

[0023] For simplicity, the following discussion concerns controlling pulses to reduce NVH in the context of electric motors used in electric and / or hybrid vehicles. It should be understood that the following discussion should not be construed as restrictive. Rather, the same or similar pulse strategies described herein are equally applicable to motors operating as generators and in a variety of different applications, such as appliances (e.g., washing machines, dryers, and dishwashers), HVAC equipment (e.g., compressors), etc.

[0024] Efficiency Chart

[0025] refer to Figure 1 Figure 10 illustrates the essence of the problem defined above. Specifically, Figure 10 graphically shows the efficiency of a representative motor at a wide variety of different motor speeds (X-axis) and torque values ​​(Y-axis). Many operating characteristics of the motor are clearly visible in Figure 10. These characteristics include:

[0026] (a) The electric motor shown is typically most efficient when operating within a specific speed range and producing torque within a defined range. For the particular electric motor shown, the region of highest efficiency is specified by reference numeral 14, which is typically in the range of 4500 to 6000 RPM and has a torque output in the range of approximately 50 to 80 Nm. In this region 14, the energy conversion efficiency of the motor is approximately 96%. Therefore, region 14 is sometimes referred to herein as the “sweetspot,” which is the region where the given motor operates at its most efficient.

[0027] (b) At any given motor speed, there exists a corresponding maximum efficiency output torque, which is graphically illustrated by the maximum efficiency curve 16. For any given motor speed, the motor efficiency tends to decrease slightly when the load is above or below the maximum efficiency load. In some regions, the motor efficiency tends to decrease relatively quickly, for example, when the torque output in the exemplary motor shown drops below approximately 30 Nm.

[0028] (c) Furthermore, for a given current motor speed, when the desired motor torque is below the most efficient output torque specified by curve 16, the overall efficiency of the motor can be improved by pulsed operation. Conversely, when the desired motor torque is at or above the maximum efficiency curve 16, the motor can be operated in a conventional (i.e., continuous / pulseless) manner to deliver the desired torque most efficiently.

[0029] Based on the observations defined above, it is clear that if operating conditions are controlled so that the motor almost always operates at or near the "optimal point" specified in Zone 14, the overall energy conversion efficiency of the motor can be significantly improved. Unfortunately, many applications require the motor to operate under a wide variety of torque requirements and / or significantly different motor speeds, which typically fall outside the optimal point.

[0030] One such application is in automobiles and other vehicle or mobility applications, where the electric motor is typically coupled to the vehicle's wheels or other drivetrain components (such as gearboxes, transmissions, any internal combustion engine, drive shafts, differentials, etc.). During a typical drive cycle, the motor speed can vary between zero when the vehicle is stationary and the relatively high RPMs required for highway cruising. Torque requirements can also vary considerably at any of these speeds based on components such as whether the vehicle is accelerating or decelerating, whether it is going uphill or downhill, whether it is traveling on relatively flat terrain, vehicle weight, and many other factors. Of course, electric motors used in other applications may also be subjected to a variety of different operating conditions.

[0031] Pulse control is used to intelligently and intermittently modulate the motor output between a "torque-on" state and a "zero (no) torque" state in order to: (1) meet measurable torque requirements while (2) improve overall efficiency. In other words, under selected operating conditions, the motor is driven intermittently at a more efficient energy conversion operating level ("torque-on" state) to deliver the desired output. Ideally, the motor does not generate or consume any torque during the time intervals between pulses ("zero torque" state). Conceptually, this can be considered as the motor being "off". In some implementations, this can be achieved by effectively "off" the motor, for example by cutting off the drive current of the motor or the excitation current of the generator. However, in other implementations, the motor can be controlled during the "zero torque" state in a manner that attempts to make the torque generated by the motor zero or close to zero (which is practical or suitable for a particular motor). In some implementations, any power converter used in conjunction with the motor can also be effectively turned off during at least a portion of the "zero torque" time interval.

[0032] Figure 1 The efficiency graph shown here, which is for the internal permanent magnet synchronous motor used in the 2010 Toyota Prius, is merely illustrative. While the operating characteristics of each graph will vary from motor to motor, a similar efficiency graph can be generated for almost any motor. Therefore, Figure 1 The diagram should not be interpreted as restrictive in any way.

[0033] Pulse motor operation and duty cycle

[0034] Figure 2 Figure 20 illustrates an example of a pulsed motor in operation. In this particular example, the desired motor torque output is 10 Nm (as specified by dashed line 22). The peak efficiency of this particular motor is 50 Nm of torque output.

[0035] Figure 20 helps illustrate how the motor operates in different modes, each producing a desired motor torque of 10 Nm. However, as explained below, the motor efficiency can be improved depending on the selected operating mode.

[0036] In the first mode, the motor can run continuously, producing a stable output of 10 Nm. As mentioned above, since a stable output of 10 Nm is far below the motor's most efficient output, this operating mode is clearly not ideal from an efficiency perspective.

[0037] In the second mode, the motor can be driven at its peak efficiency output of 50 Nm, but with a duty cycle of only 20%, and delivers zero (no) torque for the remaining 80% of the time. In other words, the same net output of 10 Nm is achieved by using a 20% (20%) duty cycle to pulse the motor at its peak efficiency of 50 Nm and turning it off for the remaining 80% (80%) of the time between pulses, but with a significantly improved overall efficiency of the motor.

[0038] Figure 2 The second operating mode is demonstrated. The amplitude of pulse 24 is 50 Nm, and the time period or frequency is one time unit out of every five time units (i.e., 20%). During the middle four time periods (80%), the motor is controlled to produce zero torque. The end result is an average torque output of the desired 10 Nm, but with a significant improvement in overall efficiency because the motor operates almost exclusively within its peak efficiency range.

[0039] The second operating mode may be significantly different to meet varying, measurable torque requirements. For example:

[0040] (a) If the desired motor output is changed to 20 Nm, the duty cycle of a motor operating at 50 Nm can be increased to 40%.

[0041] (b) If the desired motor output is changed to 40 Nm, the duty cycle can be increased to 80%;

[0042] (c) If the desired motor output is changed to 5 Nm, the duty cycle can be reduced to 10%, etc.

[0043] Provided the desired motor output does not exceed a peak efficiency of 50 Nm, the desired motor output can be achieved simply by changing the duty cycle of a motor operating at 50 Nm. As each of these examples demonstrates, applying a pulse to the motor will advantageously produce an efficiency benefit when the desired motor torque drops below the maximum efficiency curve 16.

[0044] The frequency or timing of the actual on / off time units used can vary considerably based on the size, nature, and design requirements of any particular motor system. In practice, the fact that the motor actually switches back and forth between these states from a measurable perspective may not materially degrade motor performance when the motor switches relatively quickly from a “torque-on” state to a “zero-torque” state to achieve the desired duty cycle. In some embodiments, the timing of each on / off cycle period can vary considerably. For example, in the U.S. patent applications listed above, the anticipated on / off cycle is described as approximately 100 microseconds to 0.10 seconds (i.e., applying a pulse at a frequency in the range of 10 Hz to 10,000 Hz), such as in the range of 20 Hz to 1000 Hz or 20 Hz to 100 Hz. The appropriate pulse frequency can be a function of the type of controlled motor and the tolerance of NVH that may be introduced by the pulse.

[0045] Conceptually, the zero-torque portion of a pulse cycle can be considered as cutting off the motor, although in many cases the motor may not actually be cut off during these time periods, or may only be cut off during a portion of the “zero-torque” interval.

[0046] Pulse of an AC motor

[0047] Many electric motors used in ordinary passenger cars are designed to run on alternating current (AC). However, this is by no means a necessary condition. For other vehicles, the electric motors used can be permanent magnet AC, induction AC, and / or DC.

[0048] Figures 3A to 3C These are plots illustrating the difference between continuous alternating current and pulsed alternating current that can be input to a motor operating as an electric motor (e.g., a three-phase induction motor). In each plot, the current is drawn on the vertical axis and the time on the horizontal axis.

[0049] Figure 3A The typical sinusoidal three-phase input currents 26a, 26b, and 26c delivered to the motor are shown. Phase B, represented by 26b, leads phase A, represented by 26a, by 120 degrees. Phase C, represented by 26c, leads phase B by 120 degrees. The period of the sine wave is τ. The three-phase input power 26 is continuous (non-pulsed) and has a specified maximum amplitude of approximately 50 amps. It should be understood that 50 amps is merely a representative value, and the current can have any value.

[0050] Figure 3B and Figure 3C Two examples of different pulsed three-phase currents, 28A-C and 29A-C, are shown, each with a 50% duty cycle and a peak amplitude of approximately 100 amps. Figure 3AAs shown, the period of the reference sine wave is τ; however, the sine wave is now modulated to be intermittent. Assuming the motor speed is constant and the generated torque is substantially proportional to the current (which is usually the case), Figure 3B and Figure 3C The delivered current produces the same average torque as the continuously applied three-phase input current in Figure 3. The difference between pulse currents 28a-c and 29a-c lies in the duration of their respective current pulses and the staggered "off" periods.

[0051] exist Figure 3B In the process, the current pulse 28a-c is interleaved with equal-length "off" and "on" time periods, both of which are 2τ.

[0052] exist Figure 3C In this case, the current pulses 29a-c and the interleaved "off" time periods also have equal durations. The duration in this case is τ / 2.

[0053] In both examples, the duty cycle is 50%. However, the durations of the "on" and "off" periods differ (i.e., the pulse modulation frequencies differ). The pulse modulation frequency may vary depending on the type of motor used, noise and vibration considerations, the speed of the currently running rotor, and other components.

[0054] Figures 3B to 3C This illustrates a scenario where, while the motor is operating at its desired steady-state output level, the "on" motor drive pulses are evenly spaced. This approach works well in many cases but is not essential. The duty cycle does not need to be 50% but can be adjusted to match the desired average output torque. Furthermore, the phases of the on / off pulses do not need to be synchronized with the phase of the applied AC power. Therefore, the relative magnitudes and / or timings of the motor drive pulses can vary, as long as they reach an average to deliver the desired torque.

[0055] Electric motors and vehicles

[0056] Electric and / or hybrid vehicles are now commonplace and increasingly popular. It is predicted that within the next ten or twenty years, electric and / or hybrid vehicles will surpass or completely replace traditional internal combustion engine vehicles.

[0057] For electric and / or hybrid vehicles, one or more onboard motors are provided. In the case of electric vehicles, only the motor(s) are used to generate the torque required to propel the vehicle. In hybrid vehicles, the motor works in conjunction with the internal combustion engine to propel the vehicle. For either type of vehicle, the torque generated by the motor can be positive or negative (i.e., the motor operates as a generator) to convert the vehicle's kinetic energy into stored electrical energy. For example, in regenerative braking, the motor is typically used to convert mechanical energy into electrical energy, which is stored in storage devices such as batteries or capacitors. When the motor operates as an electric motor, the stored energy can be used by the motor or alternatively power other electrical systems on the vehicle, such as air conditioning, heaters, defrosters, various lighting systems, entertainment systems, etc.

[0058] When in a vehicle, the pulses from the onboard motor offer a significant advantage in improving efficiency. By increasing efficiency, as in the case of a hybrid vehicle, the vehicle's range can be increased before the need for battery recharging and / or refueling. For example, if an electric vehicle with a range of 300 miles can increase its range by 10 percent by operating its onboard motor more efficiently, the range will be extended by approximately an additional 30 miles.

[0059] Vehicles and NVH

[0060] In the automotive and truck industry, NVH (Noise, Vibration, and Harshness) is a primary design consideration. If a vehicle's NVH is too high, the experience for the driver and other occupants can become unpleasant. Furthermore, excessive NVH can lead to premature vehicle wear. Therefore, the industry strives to reduce NVH as reasonably as possible. When addressing NVH-related issues, three factors are typically considered:

[0061] (1) Sources of NVH. Generally, anything connected to the vehicle that vibrates, generates noise, or produces roughness (such as the engine, electric motor, transmission components, wheels, open windows, exhaust system, tire / road noise, gearbox, differential, etc.) is considered a source of NVH;

[0062] (2) Engineering steps to reduce NVH transmission to the driver or other occupants in the vehicle. For example, engine or motor mounting, active vehicle suspension, noise and damping materials are examples of steps and / or materials used by automotive engineers to reduce NVH transmission; and

[0063] (3) Features included on the vehicle that are used to (a) mask or reduce the amount of NVH perceived by the occupants, or (b) adjust the amount of NVH that is considered acceptable. For example, some vehicles now have active noise or vibration systems to counteract noise and vibration within the vehicle's cabin. Other vehicles (such as sports cars) may have active sound enhancement systems that increase noise within the vehicle's cabin to produce a more pleasant engine sound. Other vehicles may have driver-selectable modes that adjust the amount of NVH that is considered acceptable. If the vehicle is equipped with an Eco or Sport mode, the amount of NVH that is considered acceptable will generally increase when either mode is used. In other words, with Eco and Sport modes, the driver consciously decides to forgo lower levels of NVH to improve economy or performance, respectively. On the other hand, vehicles may also have a Comfort mode, in which active steps are taken to reduce NVH levels. In the latter mode, the driver consciously decides to forgo economy to improve comfort.

[0064] Define pulse parameters for vehicle applications

[0065] For motor pulses used in vehicle applications, key parameters for pulses that meet torque requirements include (1) amplitude, (2) duty cycle, and (3) frequency. For vehicles powered by electric motors, for a given torque request and motor speed, the pulse amplitude is largely determined by the optimal efficiency value of the motor (i.e., by, for example, the efficiency value of the motor). Figure 1 The maximum efficiency curve (defined by the "optimal point") determines the operating frequency. Optimal and economical operation can be achieved by applying pulses at or near the "optimal point." Determining the duty cycle is relatively simple when the pulse amplitude is known. The duty cycle is determined by the ratio of the requested torque to the optimal torque when the motor is operating at its optimal efficiency. Therefore, the first two parameters are easily determined.

[0066] However, determining the third parameter (pulse frequency) is more challenging because there are opposing factors to consider. In automotive applications, low-frequency pulses from the motor can cause mechanical vibrations. Since humans are most sensitive to low-frequency mechanical vibrations in the 2 to 10 Hz frequency range, pulse frequencies within this range can lead to high or even unacceptable NVH levels. Therefore, for vehicles, the ideal pulse frequency is typically at a relatively high frequency rate, but not so high that some or all of the efficiency gain generated by the pulse operation is lost in switching transients. The goal is then to select the minimum pulse frequency for a given torque demand and speed in order to maintain or preserve the efficiency gain while meeting acceptable NVH levels.

[0067] Measurable parameters and / or characteristics of vehicles that affect NVH

[0068] One aspect of this application is the selection of pulse frequencies for motors used in vehicles. This application teaches that many other considerations can also be used to adjust or “fine-tune” the pulse frequency in order to (1) achieve a high level of economy while (2) provide a driving experience with acceptable NVH levels, rather than simply selecting the pulse frequency based on avoiding the 2 to 10 Hz frequency range. Such other considerations include numerous measurable parameters of the vehicle's own components and / or vehicle characteristics that may affect what is considered an acceptable level of NVH. Exemplary components and / or characteristics, and how they can affect NVH, will be discussed below.

[0069] Gear assembly

[0070] Electric vehicles with multi-speed gearboxes generally have higher operating efficiency than electric vehicles with only a single speed. Utilizing multiple gear ratios, the vehicle's motor can operate more efficiently over a wider range of speeds and / or torques. However, for electric vehicles and / or hybrid vehicles with multi-speed gearboxes, each speed can result in a different resonant frequency for the vehicle and / or drivetrain. For example, the resonant frequency might be 15Hz in one speed but 25Hz in another. Therefore, the frequency at which pulses are applied to the motor should be selected so as not to disturb the resonant frequency of the gears used by the vehicle. Thus, the pulse frequency is preferably selected to (a) avoid or disturb the resonant frequency and (b) improve efficiency.

[0071] Wheel drive status

[0072] Many electric and / or hybrid vehicles include multiple motors, with one or potentially multiple motors per wheel. With multiple motors, the vehicle can operate in different wheel drive configurations at any given time. For example, depending on driving conditions or environment, a given vehicle can operate in rear-wheel drive only (RWD), front-wheel drive only (FWD), or all-wheel drive (AWD). For most vehicles, NVH characteristics differ depending on the wheel drive configuration because individual motors can be connected or disconnected from the drivetrain. Furthermore, the vehicle's resonant frequency can vary depending on which motors are connected and active, and which are disconnected and inactive. Therefore, for each possible combination, the vehicle will exhibit different NVH characteristics. Thus, the pulse frequency is preferably adjusted for each possible wheel drive configuration based on the current wheel drive state. Again, the goal is generally to improve fuel economy and efficiency without producing excessively high levels of NVH.

[0073] Vehicle weight or load

[0074] As is well known in physics, force equals mass multiplied by acceleration (F = M × A). As a general rule for a given excitation force, the greater the mass, the slower the mass acceleration or vibration. For vehicles, this physical law generally means that the more weight and / or load a vehicle carries, the lower its NVH (noise, vibration, and harshness) will be. Under heavy loads (such as multiple passengers or heavy cargo), the amount of NVH will tend to be less than if the vehicle has only one driver or is not carrying cargo or is carrying lighter cargo. Therefore, as a general rule, lower pulse frequencies can be used for higher-weight vehicles and / or vehicles carrying heavy loads compared to lighter vehicles or vehicles carrying light or no cargo. Variations in vehicle mass can also affect the vehicle's natural frequencies. Therefore, the motor pulse frequencies to avoid may also vary with vehicle mass. This may lead to avoiding lower frequencies for higher vehicle masses.

[0075] Motors and / or ICE brackets

[0076] In most electric vehicles, brackets are used to attach the motor to the vehicle's drivetrain. In hybrid vehicles, brackets are also used between the vehicle's internal combustion engine (ICE) and the chassis and / or drivetrain. In either case, brackets serve to mechanically isolate the motor or ICE and prevent vibrations from being transmitted to other parts of the vehicle, including the passenger compartment. While brackets generally reduce NVH (noise, vibration, and harshness), they do have some drawbacks. First, brackets typically perform best at warm operating temperatures. Therefore, in cold conditions (such as at low ambient temperatures or after a cold start), brackets may be less effective at preventing vibration transmission. Second, as brackets age, they tend to lose their effectiveness in suppressing vibration transmission. Either way, more NVH is typically transmitted along the drivetrain and via other paths to the vehicle's occupants. Therefore, the pulse frequency used to apply pulses to the motor can be stronger when the bracket is warmer and / or newer, meaning a lower pulse frequency can be used. On the other hand, for aging brackets, cold starts, and / or cold ambient temperatures, a higher pulse frequency can be used to avoid producing excessively high levels of NVH.

[0077] User-adjustable features

[0078] Many vehicles now include features that allow setting or adjusting permissible NVH levels. Such features include, but are not limited to, Eco or “eco” modes, Sport mode, Luxury mode, or selectable NVH level modes. In Eco mode, the driver can choose to improve efficiency at the expense of additional NVH. Therefore, the pulse frequency used in Eco mode can be stronger (i.e., a lower pulse frequency) compared to when the vehicle is in non-Eco mode. Similarly, in Sport mode, the driver chooses to achieve higher performance at the expense of increased NVH. For a higher level of acceptable NVH, a lower, stronger pulse frequency can be used. Conversely, if the driver selects Luxury mode or a similar mode, a lower NVH level is expected. Therefore, a milder pulse frequency (i.e., a higher pulse frequency) should be used, resulting in less NVH from the motor. If the vehicle has adjustable NVH control, the pulse frequency can also be adjusted according to the NVH setting. If the driver selects more or less NVH as acceptable, the pulse frequency can be adjusted lower or higher, respectively.

[0079] Occupancy and / or autonomous driving

[0080] Autonomous driving is in its early stages of development and deployment. However, it is expected to become commonplace in the near future. With autonomous driving, vehicles can operate with or without a driver or passengers (multiple passengers). In the absence of passengers, NVH constraints can be relaxed because there is no one inside the vehicle. Therefore, when the occupancy sensors in the vehicle do not detect passengers, a stronger (i.e., lower) pulse frequency can be used compared to when a driver and / or passengers are present.

[0081] Ambient temperature

[0082] When operating in warmer temperatures rather than colder temperatures, vehicles tend to run more smoothly and have lower NVH (noise, vibration, and harshness). In cold environments, and before the vehicle warms up to its normal operating temperature, excessive NVH may occur. For example, cold ambient temperatures can cause various vehicle components (such as body panels, exhaust pipe hangers, suspension systems, tires, etc.) to adversely generate more NVH. Therefore, the pulse frequency can be adjusted upwards or downwards depending on whether the ambient temperature is cold or hot. As the vehicle warms up and / or as the ambient temperature warms up, the pulse frequency can be decreased accordingly.

[0083] Model

[0084] As previously mentioned, when a vehicle's drivetrain and / or other components are cold, they tend to generate more NVH (Noise, Vibration, and Harshness). As the vehicle warms up and reaches its operating temperature, NVH levels typically decrease. Similarly, new vehicles generally generate less NVH than older vehicles. Due to wear, vehicle components such as engine mounts, shock absorbers, and springs become less effective and tend to transmit more NVH. In non-exclusive embodiments, a vehicle may include software programs or algorithms (hereinafter collectively referred to as "models") that predict NVH during operation. For example, one model may be used to predict NVH levels when the vehicle warms up immediately after a cold start. Another model may be used to predict NVH as the vehicle ages. In either case, the model may be used to predict the NVH levels generated by the vehicle during operation. The pulse frequency can then be adjusted based on the predicted NVH. Again, a higher pulse frequency is typically used when a higher NVH level is predicted. A lower pulse frequency may be used when a lower NVH level is predicted.

[0085] Active noise and / or vibration control

[0086] Many vehicles now include active noise and / or vibration control systems that can be used to eliminate NVH (noise, vibration, and harshness). For example, some cars now employ active noise cancellation technology through the vehicle's audio system to eliminate noise penetrating into the cabin. Similarly, many vehicles also have adjustable suspension systems (such as magnetic ride control) that prevent vibrations from reaching the vehicle's (multiple) occupants in the passenger compartment. Because these systems mask a certain amount of NVH, stronger (i.e., lower) pulse frequencies can be used compared to situations where such systems are not used.

[0087] Road conditions

[0088] Many vehicles now include devices that enable the monitoring of road conditions. These devices include, for example, onboard cameras for cruise control and other forms of autonomous driving, radar and / or lidar, and GPS. In each case, the road conditions of the road on which the vehicle is traveling can be monitored and determined. Under poor road conditions (e.g., potholes, surface cracks, paved surface wear, etc.), the vehicle will inevitably experience high levels of NVH (noise, vibration, and harshness). In contrast, the NVH level on smooth roads is much lower. Therefore, the pulse frequency can be adjusted according to the road conditions. When the road surface is uneven, the pulse frequency of the motor can be stronger (i.e., a lower pulse frequency) because the NVH from the road surface will mask any NVH caused by the pulses from the motor(s). When the road surface is smooth, the pulse frequency is preferably increased so that the NVH from the operation of the motor(s) does not cause noticeable or excessive NVH.

[0089] surface

[0090] In the above discussion of (a) gearing, (b) wheel drive status, (c) vehicle mass and / or load, (d) brackets, (e) user-adjustable features (e.g., eco mode, sport mode, luxury mode and / or NVH adjustable level), (f) temperature sensors and / or occupancy sensors, (g) model, (h) active noise or vibration cancellation system and / or (i) road surface monitoring equipment, it is recommended that the pulse frequency be adjusted or “fine-tuned” to take into account various operating conditions and environments, as well as any of the parameters or features (a) to (i) discussed above. By fine-tuning the frequency up or down, (1) a higher level of economy can be achieved, while (2) an “acceptable” NVH level is always provided, which can vary depending on conditions and environment. For each of (a) to (i), many different methods can be used to determine the pulse frequency that satisfies the above objectives (1) and (2). Such methods include, but are not limited to, the use of tables, sliding scales, multipliers / dividers, etc.

[0091] One proposed approach to selecting pulse frequencies is to use one or more tables that allow for more or less NVH when conditions permit, without resulting in excessively high levels of NVH. This approach involves constructing one or more tables using empirical data on a given vehicle-motor or motor combination. Based on this data, multiple tables are constructed that define ideal or preferred pulse frequencies for various operating conditions that allow for more or less intense pulse frequencies when conditions permit, meaning allowing for more or less NVH without resulting in excessively high levels of NVH.

[0092] refer to Figure 4 An exemplary Table 40 is provided. Table 40 lists the motor pulse frequencies for a vehicle operating in the first (1st) gear of the gearbox at various torque demands (Nm) and motor speeds. For example, Table 40 indicates a preferred pulse frequency of 13Hz, as indicated by circle 42, suitable when the torque demand is 10Nm, the speed is 40rpm, and the gearbox is in the first gear. When the vehicle is operating in the first gear, Table 40 can be accessed as the torque demand changes and / or the speed changes. Therefore, Table 40 can be indexed when driving conditions change, and different pulse frequencies can be defined based on the current torque demand and speed. Note that the specific frequencies listed in the table are merely exemplary and should not be construed as limiting in any way.

[0093] For simplicity, only one table 40 is described and shown. It should be understood that in most real-world applications of vehicles, multiple tables are typically used. In some non-exclusive embodiments, multiple tables are typically provided for each of (a) to (i) as defined above. For example, tables are provided for (a) each gear in the gearbox, (b) each possible configuration of wheel drive, (c) various different loads, and (d) to (i). In each case, the various pulse frequencies provided in the tables are created based on empirical data collected during testing of a given vehicle-(multiple) motor combination. Once the vehicle testing is complete and the empirical data has been collected and processed, separate tables can be constructed. In each case, the pulse frequencies are preferably selected to allow for more or fewer strong pulse frequencies, which means more or less NVH without producing excessively high levels of NVH, while maximizing efficiency for a given set of conditions and / or environments.

[0094] It should also be noted that tables do not necessarily have to be two-dimensional (e.g., Figure 4 The table shown can have more than two dimensions. For example, with a gear mechanism, a three-dimensional table indexed by torque demand, motor speed, and individual gears (i.e., 1st gear, 2nd gear, 3rd gear, etc.) can be constructed instead of a separate or different table for each gear. Furthermore, any of the remaining listed parameters and / or features (b) through (i) can also rely on two-dimensional or more than two-dimensional tables. In yet another embodiment, a dedicated set of one or more tables is not necessarily required for each of the parameters and / or features (a) through (i). In other embodiments, suggested pulse frequencies for multiple parameters and / or features can be combined into a single table or a set of related tables. For example, driver-selectable features (such as different driving modes (e.g., eco, sport, luxury, etc.)) can all be combined into a single table.

[0095] Sliding scale and multiplier / divider

[0096] In other non-exclusive embodiments, a sliding scale and / or multipliers / dividers can be used to determine the pulse frequency for any of (a) to (i). For example, a sliding scale or multiplier can be used for vehicle mass and / or load (c). In other words, the pulse frequency is adjusted downwards or upwards, respectively, as the vehicle's load mass increases or decreases. Alternatively, multiplier / divider values ​​can be used to adjust the base pulse frequency for any of (a) to (i). In variations of these embodiments, the scaling factor and / or divider / multiplier can be linear or non-linear. In the latter case, the scaling and / or multiplier / divider algorithm can be used to determine the pulse frequency in a non-linear manner based on conditions and environment.

[0097] Motor controller architecture

[0098] refer to Figure 5A A block diagram of a power control architecture 50 is shown. Architecture 50 includes a power converter 52, a DC power supply 54, a motor 56, a pulse controller 58, one or more inputs 60, and one or more tables 40. Additionally, the pulse controller 58 is arranged to receive torque demand and motor speed inputs. In an alternative embodiment, the pulse controller 58 includes a calculation module 62.

[0099] The power converter 52 operates as either a power inverter or a power rectifier, depending on the direction of energy flow through the system. When the motor 56 operates as a motor, the power converter 52 is responsible for generating three-phase AC power from the DC power supply source 54 to drive the motor 56. The three-phase input power, labeled as phase "A", phase "B", and phase "C", is applied to the stator windings of the motor 56, as is well known in the art. When the motor 56 operates as a generator, the power converter 52 operates as a power rectifier, and the AC power from the motor 56 is converted into DC power stored in the DC power supply source 54.

[0100] In various embodiments, the power controller 52 may be a conventional power converter or a “boost” power converter, both of which are described in detail in commonly assigned U.S. Application No. 16 / 818,570, filed March 13, 2020, which is incorporated herein by reference for all purposes.

[0101] The pulse controller 58 is also responsible for (1) defining when the motor 56 should operate in continuous mode or pulse mode, (2) defining the pulse amplitude, pulse frequency, and duty cycle of the three-phase input power signals A, B, and C in pulse mode, and (3) providing control signals so that the power converter 52 can continuously generate or pulse the three-phase power signals A, B, and C to the motor 46. During pulse operation, the three-phase power signals A, B, and C are pulsed according to any amplitude, duty cycle, and pulse frequency determined by the pulse controller to meet the torque requirements at a given speed.

[0102] As mentioned earlier, determining the amplitude and duty cycle for a given torque requirement and speed is relatively straightforward. The amplitude is selected so that the motor 56 operates within or near its "optimal point" of maximum efficiency, while the duty cycle is adjusted as needed to ensure that the motor's torque output meets the requested torque. However, determining the pulse frequency is more complex due to the effects of NVH (Noise, Vibration, and Harshness).

[0103] To determine the pulse frequency, the pulse controller 58 receives one or more inputs 60 (see...). Figure 5BThe possible input list, all of which have been previously described. In response, the pulse controller 58 accesses any one or all of (a) to (i) defined above in Table 40 and determines a pulse frequency that maximizes efficiency without generating excessive NVH for a given set of inputs, operating conditions, and environment. In this way, the motor 56 operates at or near its maximum efficiency level (e.g., see [reference]). Figure 1 The curve 16) allows for more or less NVH when conditions permit, but never produces excessively high levels of NVH. As described above, in alternative embodiments, the calculation module 62 can be used to scale, multiply, divide, or apply algorithms to determine the pulse frequency. In various embodiments, the calculation module may include a lookup table, a multidimensional lookup table, a sliding scale, a multiplier, a processor, a logic unit, a trained neural network, or any combination thereof.

[0104] It should be noted that the inputs listed in Figure 5 are merely exemplary and should not in any way be construed as exhaustive. Rather, the number and type of inputs can vary considerably and should not be limited to those explicitly mentioned herein.

[0105] During driving, various torque demands will arise, and the motor speed will vary depending on the gear and as the vehicle accelerates and / or decelerates, goes uphill or downhill, etc. In response, the pulse controller 58 adjusts the amplitude and duty cycle of the pulses as needed and determines different pulse frequencies to meet instantaneous torque demands while preventing excessive NVH levels. When conditions permit, a stronger pulse frequency can be used to improve efficiency and economy. Alternatively, a less intense pulse can be used to prevent excessive NVH. Therefore, the vehicle can operate efficiently overall while selectively controlling the NVH level generated by the motor 56 to prevent or mitigate excessive NVH levels.

[0106] Shared pulse frequency

[0107] In yet another embodiment, the pulse frequency defined by the pulse controller 58 can also be forwarded to other subsystems 64 on the vehicle, which can utilize the information in a meaningful way. One example is providing the pulse frequency to (multiple) subsystems 64 (such as active noise and / or vibration control), which can use the pulse frequency information as a reference / feedforward signal to identify the target frequency to be eliminated.

[0108] flow chart

[0109] refer to Figure 6 The flowchart 70 shows the steps implemented by the motor controller architecture 50.

[0110] In the initial step 72, the current torque request and motor speed are determined.

[0111] In decision step 74, based on the determined current torque request and speed, it is determined whether motor 56 should operate in continuous mode or pulse mode. In other words, it is determined whether the desired torque demand is higher or lower than the most efficient output torque at the current speed (i.e., Figure 1 The maximum efficiency curve of the motor diagram shown in Figure 16). If the desired torque is higher than the optimal torque, the motor operates in continuous mode instead of pulse mode. If it is lower than the most efficient output torque, the motor operates in pulse mode.

[0112] In step 76, if the requested torque is higher than the most efficient output torque at the current motor speed, the motor is operated in continuous mode.

[0113] In step 78, if the requested torque is lower than the most efficient output torque at the current motor speed, the amplitude of the pulse with the maximum efficiency at the current motor speed is determined.

[0114] In step 80, the duty cycle for pulse mode operation is determined such that the average torque output of the start pulse matches the desired output.

[0115] In step 82, the pulse frequency is determined by the pulse controller 58. As described above, the pulse controller determines the pulse frequency by accessing one or more tables 40 and / or relying on the calculation module 62. As previously stated, one or more of the inputs (a) to (i) can indicate that the pulse frequency is adjusted upward to reduce NVH, or downward if more NVH is acceptable or permissible.

[0116] Steps 72 to 82 above are performed continuously while motor 56 is running. At any given motor speed and torque demand, there will be a corresponding most efficient output torque. As the instantaneous torque demand and / or the current motor speed change, a decision is made as to whether to operate the motor in continuous or pulsed mode. When the desired motor torque is lower than the most efficient output torque at the current motor speed, the overall efficiency of the motor is improved not only by applying pulses to the motor but also by adjusting the pulse frequency to take into account inputs (a) to (i). Therefore, for motor-powered vehicles, the overall efficiency of the vehicle is improved; this means that while achieving acceptable NVH levels, the vehicle's driving range between battery recharges (or refueling in hybrid vehicles) is extended.

[0117] Competitive Input

[0118] Sometimes, two or more of the inputs (a) to (i) may suggest or indicate that the base pulse frequency should be modified or adjusted in the opposite direction. For example, switching from the first gear to the second gear allows for a reduction in the pulse frequency. However, if the user-selectable NVH control requires a higher frequency for better NVH, adjusting the pulse frequency downward may not be feasible. On the other hand, if the vehicle is unmanned, adjusting the pulse frequency downward is not a problem. As shown in these two examples, the pulse controller 58 preferably makes a final decision on the pulse frequency individually after considering all inputs (a) to (i) and the overall environment. Note that in conflicting situations, the pulse frequency is typically adjusted to reduce NVH. However, it should be understood that this is by no means a necessary condition. Rather, for a given conflict, pulse frequency adjustment can result in an increase or decrease in NVH. Therefore, the pulse frequencies of any two or more conflicting components or features can be adjusted according to any predetermined algorithm arranged to resolve the conflict.

[0119] Real-time feedback

[0120] refer to Figure 7 The diagram illustrates real-time feedback for adjusting the pulse frequency according to another embodiment. In this embodiment, actual or sensed NVH is compared to a threshold. Based on this comparison, the pulse frequency can be adjusted upward or downward. In this implementation, the actual NVH can be measured by one or more noise and / or vibration sensors located on the vehicle (e.g., located in the vehicle's cabin or along the vehicle's drivetrain). If the comparison indicates that the sensed NVH is below the threshold, the pulse frequency can be adjusted downward until the NVH increases and matches the threshold. Conversely, if the comparison indicates that the sensed NVH is above the threshold, the pulse frequency can be adjusted upward until the NVH increases and matches the threshold. It should also be noted that in variations of this embodiment, the threshold is also adjustable. For example, if the vehicle has an NVH acceptable level controller, the threshold can be adjusted upward or downward depending on whether the driver sets the NVH level to high or low. The threshold can also be adjusted based on other inputs (e.g., eco mode, sport mode, luxury mode, etc.).

[0121] Non-exclusive embodiments

[0122] In one embodiment, the present invention relates to a motor controller for controlling pulses of an on-board motor of a vehicle. Specifically, the motor controller is arranged to determine a torque requirement for operating the motor as an electric motor, determine the amplitude of the pulsed operation of the motor as an electric motor, determine the duty cycle of the pulsed operation of the motor as an electric motor, the amplitude and the duty cycle resulting in the determined torque requirement, and determine the frequency of the pulsed operation of the motor as an electric motor when the determined torque requirement is generated, the frequency being determined by taking into account NVH caused by (a) measurable parameters of the vehicle or (b) an amount of adjustable acceptable noise, vibration, and harshness (NVH) on the vehicle.

[0123] In another embodiment, the present invention relates to a method for pulse control of a motor used in a vehicle. The method involves applying pulses to the motor at a frequency adjusted to account for NVH caused by one or more components of the vehicle or features that allow for adjustment of acceptable levels of noise, vibration, and harshness (NVH).

[0124] In yet another embodiment, the present invention relates to a motor controller for controlling pulses to a motor. The motor controller is configured to receive a signal indicating a magnitude of noise, vibration, and harshness (NVH), compare the NVH magnitude with a threshold, and adjust the pulse frequency used to apply pulses to the motor when the NVH magnitude exceeds the threshold, the pulse frequency being adjusted such that the NVH magnitude is reduced below the threshold.

[0125] Other motor types and applications

[0126] As should be apparent from the foregoing description, the described pulsed motor control can be used in a variety of applications to improve the energy conversion efficiency of various types of motors and generators. These motors and generators include AC motors / generators and DC motors / generators. Several representative types of motors that can benefit from the described pulses include asynchronous and synchronous AC motors, including induction motors (IM), switched reluctance motors (SRM), synchronous reluctance motors (SynRM), permanent magnet synchronous reluctance motors (PMaSynRM), hybrid PMaSynRM; externally excited AC synchronous motors (SyncAC), permanent magnet synchronous motors (PMSM), eddy current motors, AC linear motors, AC and DC mechanically commutated motors, axial flux motors, etc. Representative DC motors include brushless motors, electrically excited motors, permanent magnet motors, series motors, shunt motors, brushed motors, hybrid motors, etc.

[0127] Additional Examples

[0128] While automotive applications have been used as an example of vehicle propulsion applications, it should be understood that the described control methods are equally beneficial in other propulsion-related applications, including: electric motors used in other types of vehicles (including trucks, cars, vans, motorcycles, bicycles, drones, and other flying devices); robots and other devices that move autonomously in their environment; and so on. Therefore, the term "vehicle" should be interpreted broadly to include all of the above and any other types of motorized mobility components, whether they are currently known or will be developed in the future.

[0129] Electric motors used in electrical appliances (such as washing machines and dryers) and heating, ventilation, and air conditioning (HVAC) applications are another excellent example of applications that can benefit from pulse control. Several factors contribute to making pulse motor control well-suited for HVAC applications. These factors include the fact that (a) motors currently used in HVAC applications are primarily induction motors without permanent magnets; (b) a high percentage of motors used in HVAC applications (particularly those including variable-speed HVAC condensers and / or air handlers) operate below their high-efficiency zone for a significant portion of the time; and (c) the inertia of fans or pumps typically dominates motor inertia, which tends to further mitigate the potential NVH-related effects associated with pulses.

[0130] Although only a few embodiments of the invention have been described in detail, it should be understood that the invention can be implemented in many other forms without departing from its spirit or scope. In different embodiments, the various described pulse controllers and other control elements can be implemented, grouped, and configured in a variety of different architectures. For example, in some embodiments, the pulse controller may be integrated into a motor controller or an inverter controller, or it may be provided as a separate component. Similarly, for a generator, the pulse controller may be integrated into a generator controller or a rectifier controller, and in a combined motor / generator, the pulse controller may be integrated into a combined motor / generator controller or a combined inverter / rectifier controller. In some embodiments, the described control functions can be implemented algorithmically by software or firmware executing on a processor, which can take any suitable form, including, for example, general-purpose processors and microprocessors, DSPs, etc.

[0131] A pulse generator or motor controller can be part of a larger control system. For example, in vehicle applications, the described control can be part of a vehicle controller, powertrain controller, hybrid powertrain controller, or ECU (engine control unit) that performs various functions related to vehicle control. In such applications, the vehicle controller or other related controllers can take the form of a single processor performing all the required controls, or can include multiple processors that are commonly located as part of a powertrain or vehicle control module, or distributed throughout the vehicle. The specific functions performed by any one of the processors or control units can vary considerably.

[0132] Typically, pulse motor control schemes can be implemented digitally and algorithmically using analog components or a hybrid approach. The pulse generator and / or motor controller can be implemented as code that executes on a processor, on programmable logic such as an FPGA (Field-Programmable Gate Array), on a circuit system such as an ASIC (Application-Specific Integrated Circuit), or on a digital signal processor (DSP), using analog components or any other suitable hardware. In some implementations, the described control scheme can be incorporated into target code to be executed on a digital signal processor (DSP) incorporated into an inverter controller (and / or a rectifier controller in the context of a generator, and / or a combined inverter / rectifier controller).

[0133] Therefore, this embodiment should be considered illustrative rather than restrictive, and the invention is not limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

Claims

1. A motor controller for controlling pulses of an on-board motor of a vehicle, the motor controller being arranged as follows: Determine the torque requirements for operating the motor as an electric motor; Determine the amplitude of the pulse operation of the motor as the motor; The duty cycle of the pulse operation of the motor is determined, and the amplitude and the duty cycle result in the determined torque demand. and When generating the determined torque demand, the frequency of pulsed operation of the motor as an electric motor is determined by taking into account the NVH caused by (a) a measurable parameter of the vehicle or (b) a quantity of adjustable acceptable noise, vibration, and roughness NVH on the vehicle, wherein the measurable parameter and / or characteristic is selected from the group consisting of: (a) Gearbox state, wherein a first pulse frequency is used in the first gear and a second pulse frequency different from the first pulse frequency is used in the second gear; (b) Wheel-driven state; (c) The weight of the load carried by the vehicle; (d) Optional economic models; (e) Optional sports modes; (f) Allows the driver to select an optional NVH controller with different levels of acceptable NVH; (g) Sensed vehicle occupancy rate; (h) Sensed temperature; (i) A first model that models the NVH characteristics of the vehicle as it ages; (j) A second model for modeling the NVH characteristics of the vehicle after a cold start; (k) Active noise control system; (l) Active vibration control system; (m) Road surface condition; or Any combination of (n) (a) to (m); Each gear position of the gearbox is characterized by a different resonant frequency, which is determined to avoid different resonant frequencies for each gear position of the gearbox; When a conflict is determined to exist in a frequency based on two or more of (a) to (n), the frequency is determined according to a predetermined algorithm arranged to resolve the conflict.

2. The motor controller as described in claim 1, wherein, The measurable parameter of this vehicle is its wheel drive status.

3. The motor controller as described in claim 2, wherein, The vehicle's wheel drive states include one of front-wheel drive (FWD), rear-wheel drive (RWD), and all-wheel drive (AWD), and the determined frequencies are adjusted for vehicles operating in FWD, RWD, and AWD respectively.

4. The motor controller as described in claim 1, wherein, The measurable parameter is the weight of the load carried by the vehicle, and the determined frequency is adjusted as the weight of the load carried by the vehicle increases.

5. The motor controller as described in claim 4, wherein, The weight of the vehicle and the load is characterized by the resonant frequency, and the determined frequency is adjusted to avoid this resonant frequency.

6. The motor controller as described in claim 1, wherein, The vehicle is characterized by an optional economy mode for operating the vehicle, and the frequency at which the vehicle is operated in the economy mode is determined to be lower than when the vehicle is operating in the non-economy mode.

7. The motor controller as described in claim 1, wherein, The measurable parameter is the powertrain mount’s ability to mitigate the transmission of NVH, and the determined frequency decreases or increases as the powertrain mount’s ability to mitigate the transmission of NVH increases or decreases.

8. The motor controller as described in claim 1, wherein, The measurable parameter is the vehicle occupancy rate measured by the occupancy sensor, and the frequency determined when no occupant is detected in the vehicle is lower than when an occupant is detected in the vehicle.

9. The motor controller as described in claim 1, wherein, The measurable parameter is the temperature measured by a temperature sensor, and the determined frequency increases for cold sensing temperatures and decreases for warm sensing temperatures.

10. The motor controller as claimed in any one of claims 1 to 9, wherein, The vehicle features an optional sport mode, and the frequency determined when the vehicle is in that sport mode is lower than when the vehicle is not in that sport mode.

11. The motor controller as claimed in any one of claims 1 to 9, wherein, The vehicle features a user-selectable NVH controller that allows for selectable levels of acceptable NVH, and the determined frequency decreases as more NVH is selected as acceptable.

12. The motor controller as described in any one of claims 1 to 9, wherein, This feature is a model that models the NVH characteristics of a vehicle as it ages, and the determined frequency increases with respect to the model, indicating that the NVH characteristics of the vehicle are increasing.

13. The motor controller as described in any one of claims 1 to 9, wherein, This feature is a model that models the NVH characteristics of the vehicle after a cold start, and the determined frequencies decrease as the vehicle warms up after the cold start.

14. The motor controller as claimed in any one of claims 1 to 9, wherein, This feature is an active noise controller, and the determined frequency is adjusted when the active noise control system actively reduces or adds noise.

15. The motor controller as described in any one of claims 1 to 9, wherein, This feature is a vibration control system, and the determined frequency decreases as the active vibration control system actively reduces the vibration.

16. The motor controller as claimed in any one of claims 1 to 9, wherein, The determined frequency is selected by using one of the following: (a) Lookup table; (b) Multidimensional lookup table; (c) Sliding scale; (d) Multiplier; (e) Processor; (f) Logic unit; (g) A trained neural network; or (e) Any combination of (a) to (g).

17. The motor controller as claimed in any one of claims 1 to 9, further configured to operate the motor as a generator.

18. The motor controller of any one of claims 1 to 9, further configured to operate the motor in a continuous operating mode when the determined torque demand is below a threshold or in a pulse operating mode when the determined torque demand exceeds the threshold.

19. A method for pulse control of a motor used in a vehicle by applying pulses at a frequency adjusted to account for NVH caused by one or more components of the vehicle or features that allow adjustment of acceptable amounts of noise, vibration, and roughness NVH, wherein, The frequency response is adjusted according to one or more of the following: (a) Gearbox status; (b) Wheel-driven state; (c) The weight of the load carried by the vehicle; (d) Optional economic models; (e) Optional sports modes; (f) Allows the driver to select an optional NVH controller with different levels of acceptable NVH; (g) Occupy the sensor output; (h) Output of the temperature sensor; (i) A first model that models the NVH characteristics of the vehicle as it ages; (j) A second model for modeling the NVH characteristics of the vehicle after a cold start; (k) Active noise control system; (l) Active vibration control system; (m) Road surface condition; or Any combination of (n) (a) to (m); Each gear in the gearbox is characterized by a different resonant frequency, which is adjusted to avoid different resonant frequencies for each gear in the gearbox. The method further includes: When there is a conflict in adjusting the frequency according to two or more of (a) to (n), the frequency is adjusted according to a predetermined algorithm arranged to resolve the conflict.

20. The method of claim 19, further comprising adjusting the frequency for the front-wheel drive (FWD), rear-wheel drive (RWD), and all-wheel drive (AWD) states of the vehicle, respectively.

21. The method of claim 19 or 20, further comprising adjusting the frequency based on the weight of the load carried by the vehicle.

22. The method of claim 19 or 20, further comprising adjusting the frequency to a lower level when the vehicle is operating in the economy mode compared to when the vehicle is not operating in the economy mode.

23. The method of claim 19 or 20, further comprising adjusting the frequency to a lower level when the vehicle is operating in Sport mode compared to when the vehicle is not operating in Sport mode.

24. The method of claim 19 or 20, further comprising selectively adjusting the frequency to a lower level as the amount of acceptable NVH increases.

25. The method of claim 19 or 20, further comprising adjusting the frequency to a higher or lower level as the powertrain bracket’s ability to mitigate the transmission of NVH decreases or increases.

26. The method of claim 19 or 20, further comprising adjusting the frequency in response to the output of a model that models the NVH characteristics of the vehicle as it ages.

27. The method of claim 19 or 20, further comprising adjusting the frequency in response to the output of a model that models the NVH characteristics of the vehicle after a cold start.

28. The method of claim 19 or 20, further comprising adjusting the frequency in response to active noise cancellation or addition performed by the active noise control system.

29. The method of claim 19 or 20, further comprising reducing the frequency in response to active damping performed by the active vibration control system.

30. The method of claim 19 or 20, further comprising operating the motor as an electric motor or a generator.

31. The method of claim 19 or 20, further comprising selectively operating the motor in a continuous mode or a pulse mode, wherein in the pulse mode, pulses are applied to the motor at a frequency adjusted to take into account the NVH.

32. The method of claim 19 or 20, further comprising reducing the frequency when the road surface is uneven where the vehicle is traveling.

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