JP-2026514544-A - Pulsed electromechanical control using a notch filter

Abstract

A method is provided for controlling the operation of at least a first electromachine among at least one electromachine mounted on a vehicle having at least one resonant frequency. The pulse operation of the first electromachine is instructed to supply a desired average output, and the pulse operation causes the first electromachine to alternate between a first output level greater than the desired average output and a second output level less than the desired average output. At least several transitions between the first output level and the second output level are controlled. At least one notch filter at the at least one resonant frequency of the vehicle is provided.

Inventors

• スリニバサン，ヴィジャイ

Assignees

• トゥラ イーテクノロジー，インコーポレイテッド

Dates

Publication Date

20260511

Application Date

20240410

Priority Date

20230505

Claims (20)

1. A method for controlling the operation of at least a first electromachine among at least one electromachine mounted on a vehicle having at least one resonant frequency, The pulse operation of the first electromachine is instructed to supply a desired average output, the pulse operation causing the first electromachine to alternately switch between a first output level greater than the desired average output and a second output level less than the desired average output. Controlling at least several transitions between the first output level and the second output level, To provide at least one notch filter at the at least one resonant frequency of the vehicle, A method that includes this.
2. The method according to claim 1, further comprising providing a pulsing frequency, wherein controlling at least some transitions depends on the pulsing frequency.
3. The method according to claim 2, wherein the pulsing frequency is determined by considering noise, vibration, and harshness (NVH) caused by measurable parameters of the vehicle or features on the vehicle that adjust the acceptable amount of NVH.
4. The method according to claim 1, wherein the second output level is zero torque.
5. The method according to claim 4, wherein the first electric machine is controlled by a first inverter, and in at least some operating states, the first inverter is turned off for at least a portion of the time during which the first electric machine outputs zero torque.
6. The method according to claim 1, wherein the transition between the first output level and the second output level is controlled by controlling the torque generated by the first electromachine.
7. The method according to claim 1, wherein the transition between the first output level and the second output level is controlled by controlling the current supplied to the first electromachine.
8. The method according to claim 1, further comprising receiving vehicle resonance data from at least one of a sensor and a lookup table.
9. The method according to claim 1, wherein the at least one resonant frequency of the vehicle is variable, and the notch filter is adjustable to match the change in the at least one resonant frequency.
10. The method according to claim 1, wherein the vehicle has at least two resonant frequencies, and at least two notch filters are provided at the at least two resonant frequencies.
11. The method according to claim 1, wherein controlling at least several transitions between the first output level and the second output level is done using a transition profile of order three or higher.
12. The method according to claim 1, wherein the at least one electric machine further comprises a second electric machine, a second inverter controls the second electric machine, and at least a second notch filter is provided for the second electric machine.
13. The method according to any one of claims 1 to 3, wherein the second output level is zero torque.
14. The method according to claim 13, wherein the first electric machine is controlled by a first inverter, and in at least some operating states, the first inverter is turned off for at least a portion of the time during which the first electric machine outputs zero torque.
15. The method according to any one of claims 1 to 3 and 13 to 14, wherein the transition between the first output level and the second output level is controlled by controlling the torque generated by the first electromachine.
16. The method according to any one of claims 1 to 3 and 13 to 15, wherein the transition between the first output level and the second output level is controlled by controlling the current supplied to the first electromachine.
17. The method according to any one of claims 1-3 and 13-16, further comprising receiving vehicle resonance data from at least one of a sensor and a lookup table.
18. The method according to any one of claims 1 to 3 and 13 to 17, wherein the at least one resonant frequency of the vehicle is variable, and the notch filter is adjustable to match the change in the at least one resonant frequency.
19. The method according to any one of claims 1 to 3 and 13 to 18, wherein the vehicle has at least two resonant frequencies, and at least two notch filters are provided at the at least two resonant frequencies.
20. Controlling at least several transitions between the first output level and the second output level is done using a transition profile of order three or higher, according to any one of claims 1 to 3 and 13 to 19.

Description

Cross-reference to Related Applications : This application claims priority to U.S. Application No. 63/500,493, filed on 5 May 2023, the contents of which are incorporated herein by reference for all purposes. This application relates to electromechanical control in general. More specifically, it describes a control system and controller design that facilitates the operation of electromechanical machinery in a more energy-efficient manner by smoothly pulsing its operation under selected operating conditions. As used herein, the term "electric machine" is intended to be interpreted broadly to mean both electric motors and generators. Electric motors and generators are structurally very similar. Both include a stator and rotor with multiple poles. When an electric machine operates as a motor, it converts electrical energy into mechanical energy. When it operates as a generator, it converts mechanical energy into electrical energy. Electric motors and generators are used in a wide variety of applications and operating conditions. Generally, many modern electrical machines have relatively high energy conversion efficiencies. However, the energy conversion efficiency of most electrical machines varies significantly depending on the operating load. In many applications, electrical machines are required to operate under a wide range of operating load conditions. Therefore, many electrical machines may operate at or near their highest efficiency levels, or at lower efficiency levels. Battery-powered electric vehicles are a prime example of electromechanics that operate across a wide range of efficiency levels. In a typical drive cycle, an electric vehicle accelerates, cruises, decelerates, brakes, and corners. Within a specific rotor speed and/or torque range, the electromechanism operates at or near its most efficient operating point, or "sweet spot." Outside these ranges, the electromechanism's operational efficiency is lower. As drive conditions change, rotor speed and/or torque requirements change, causing the electromechanism to transition between high and low operational efficiency levels. If the electromechanism can operate in the high-efficiency region for a larger proportion of the drive cycle, the vehicle's range for a given battery charge level increases. Since the limited range of battery-powered electric vehicles is a major commercial barrier to their use, extending the vehicle's operating range is highly advantageous. While conventional electrical machinery generally exhibits good energy conversion efficiency, efforts continue to further improve energy conversion efficiency under a wider range of operating conditions. The present invention and its advantages are best understood by referring to the following description in conjunction with the accompanying drawings. Figure 1 shows typical torque/speed/efficiency graphs illustrating the energy conversion efficiency of representative electromechanical devices operating as electric motors under different operating conditions. Figure 2 is a graph showing the pulse current signals applied to an electromechanical device in response to torque demands when it operates as a motor. Figure 3 is a block diagram of an electromechanical controller according to a non-limiting embodiment of the present invention. Figure 4A is a diagrammatic representation of the continuous three-phase AC waveform supplied to an electrical machine. Figures 4B and 4C show different examples of pulsed three-phase AC waveforms with similar duty cycles that provide the same torque as the continuous waveform in Figure 4A. Figure 5 is a graph showing typical electromechanical system efficiency with respect to mechanical torque at a fixed machine speed. Figures 6A–6C are a series of related graphs showing angular kinetic energy, angular acceleration, and torque profiles for an exemplary third-order transition torque profile. Figures 7A–7E are a series of related graphs showing the fifth, fourth, third (angular accelerometer), angular acceleration, and torque profiles for an exemplary fifth-order transition torque profile. Figures 8A–8E are a series of related graphs showing the fifth, fourth, third, angular acceleration, and torque profiles for an exemplary fifth-order transition torque profile in a situation where the period of the desired off portion of the pulse cycle is shorter than the torque transition time. Figures 9A–9E are a series of related graphs showing the fifth, fourth, third, angular acceleration, and torque profiles for an exemplary fifth-order transition torque profile in a situation where the period of the desired ON portion of the pulse cycle is shorter than the torque transition time. Figure 10 is a schematic diagram showing the excitation graph caused by pulse operation of an electromechanical device. Figure 11A shows graphs of a rectangular wave pulse and an S-shaped curve pulse. Figure 11B is a graph showing the harmonic attenuation caused by an S-shaped curve pulse com