Pulsed electric machine control
Pulsed control of electric motors, and more particularly, to selectively adjusting one or more of a pulsing frequency, an amplitude of the pulses and/or a duty cycle of the pulses for reducing Noise, Vibration and Harshness (NVH).
1 . An electric machine on a vehicle, comprising:
a controller for controlling the electric machine, the controller configured to:
receive a torque demand;
ascertain an acceptable level of Noise, Vibration and Harshness (NVH) for operating the electric machine;
ascertain an On-Torque amplitude and a duty cycle for a series of pulses to operate the electric machine in a pulsed mode to meet the ascertained acceptable level of NVH and the received torque demand; and
operate the electric machine in the pulsed mode, using the series of pulses, the series of pulses having the ascertained On-Torque amplitude and the duty cycle,
wherein the electric machine generates a work output sufficient to meet the torque demand during the series of pulses and substantially no work output between the series of pulses.
2 . The electric machine of claim 1 , wherein the controller is further configured to:
ascertain a frequency for the series of pulses to operate the electric machine in the pulsed mode to meet the ascertained acceptable level of NVH and the received torque demand; and
operate the electric machine in the pulsed mode, using the series of pulses, the series of pulses having the ascertained frequency, the ascertained On-Torque amplitude, and the duty cycle.
3 . The electric machine of claim 1 , wherein the controller is configured to ascertain the acceptable level of Noise, Vibration and Harshness (NVH) for operating the electric machine from one or more factors.
4 . The electric machine of claim 3 , wherein the one or more factors include a gearbox status of a gearbox on the vehicle.
5 . The electric machine of claim 3 , wherein the one or more factors include a wheel drive status of a wheel drive system on the vehicle.
6 . The electric machine of claim 3 , wherein the one or more factors include a weight of a load carried by the vehicle.
7 . The electric machine of claim 3 , wherein the one or more factors include a setting of a selectable economy mode feature provided on the vehicle.
8 . The electric machine of claim 3 , wherein the one or more factors include a setting of a selectable sport mode feature provided on the vehicle.
9 . The electric machine of claim 3 , wherein the one or more factors include a setting of a selectable NVH mode feature provided on the vehicle.
10 . The electric machine of claim 3 , wherein the one or more factors includes whether or not the vehicle is (a) autonomous or not autonomous, and (b) occupied by any persons if autonomous.
11 . The electric machine of claim 3 , wherein the one or more factors includes ambient temperature around the vehicle.
12 . The electric machine of claim 3 , wherein the one or more factors includes a model of NVH characteristics of the vehicle as the vehicle ages.
13 . The electric machine of claim 3 , wherein the one or more factors includes a model of NVH characteristics of the vehicle after a cold start of the vehicle.
14 . The electric machine of claim 3 , wherein the one or more factors include a setting of an active noise control system provided on the vehicle.
15 . The electric machine of claim 3 , wherein the one or more factors include a setting of an active vibration control system provided on the vehicle.
16 . The electric machine of claim 3 , wherein the one or more factors include whether or not an internal combustion engine on the vehicle is operating.
17 . The electric machine controller of claim 3 , wherein data for ascertaining the acceptable level of NVH for operating the electric machine from the one or more factors is stored in or derived from one of the following:
(a) a look up table;
(b) a multi-dimensional look up table;
(c) a sliding scale;
(d) a multiplier;
(e) a processor;
(f) a logic unit;
(g) a trained neural network; or
(e) any combination of (a) through (g).
18 . The electric machine of claim 1 , wherein the On-Torque amplitude and the duty cycle are at least partially ascertained from a maximum On-Torque value derived from a Fundamental Amplitude Maximum (FAMax) table.
19 . The electric machine of claim 1 , wherein the controller is further configured to selectively adjust the On-Torque amplitude depending on whether the ascertained acceptable level of NVH is relatively high or relatively low as compared to a predetermined level of NVH respectively.
20 . A method for operating an electric machine on a vehicle, comprising:
receiving a torque demand;
ascertaining an acceptable level of Noise, Vibration and Harshness (NVH) for operating the electric machine;
ascertaining an On-Torque amplitude and a duty cycle for a series of pulses to operate the electric machine in a pulsed mode to meet the ascertained acceptable level of NVH and the received torque demand; and
operating the electric machine in the pulsed mode, using the series of pulses, the series of pulses having the ascertained On-Torque amplitude and the duty cycle,
wherein the electric machine generates a work output sufficient to meet the torque demand during the series of pulses and substantially no work output between the series of pulses.
21 . The method of claim 20 , further comprising:
ascertaining a frequency for the series of pulses to operate the electric machine in the pulsed mode to meet the ascertained acceptable level of NVH and the received torque demand; and
operating the electric machine in the pulsed mode, using the series of pulses, the series of pulses having the ascertained frequency, the ascertained On-Torque amplitude, and the duty cycle.
22 . The method of claim 20 , further comprising ascertaining the acceptable level of NVH for operating the electric machine from one or more factors.
23 . The method of claim 22 , wherein the one or more factors include a gearbox status of a gearbox on the vehicle.
24 . The method of claim 22 , wherein the one or more factors include a wheel drive status of a wheel drive system on the vehicle.
25 . The method of claim 22 , wherein the one or more factors include a weight of a load carried by the vehicle.
26 . The method of claim 22 , wherein the one or more factors include a setting of a selectable economy mode feature provided on the vehicle.
27 . The method of claim 22 , wherein the one or more factors include a setting of a selectable sport mode feature provided on the vehicle.
28 . The method of claim 22 , wherein the one or more factors include a setting of a selectable NVH mode feature provided on the vehicle.
29 . The method of claim 22 , wherein the one or more factors includes whether or not the vehicle is (a) autonomous or not autonomous, and (b) occupied by any passengers if autonomous.
30 . The method of claim 22 , wherein the one or more factors includes ambient temperature around the vehicle.
31 . The method of claim 22 , wherein the one or more factors includes a model of NVH characteristics of the vehicle as the vehicle ages.
32 . The method of claim 22 , wherein the one or more factors includes a model of NVH characteristics of the vehicle after a cold start of the vehicle.
33 . The method of claim 22 , wherein the one or more factors include a setting of an active noise control system provided on the vehicle.
34 . The method of claim 22 , wherein the one or more factors include a setting of an active vibration control system provided on the vehicle.
35 . The method of claim 22 , wherein the one or more factors include whether or not an internal combustion engine is operating on the vehicle.
36 . The method of claim 22 , further comprising storing or calculating data for ascertaining the acceptable level of NVH for operating the electric machine in or from one of the following:
(a) a look up table;
(b) a multi-dimensional look up table;
(c) a sliding scale;
(d) a multiplier;
(e) a processor;
(f) a logic unit;
(g) a trained neural network; or
(e) any combination of (a) through (g).
37 . The method of claim 20 , wherein the On-Torque amplitude and the duty cycle are at least partially ascertained from a maximum On-Torque value derived from a Fundamental Amplitude Maximum (FAMax) table.
38 . A vehicle, comprising:
an internal combustion engine provided on the vehicle;
an electric machine provided on the vehicle;
a controller for controlling the electric machine, the controller configured to:
receive a torque demand;
ascertain an acceptable level of Noise, Vibration and Harshness (NVH) for operating the electric machine;
ascertain an On-Torque amplitude and a duty cycle for a series of pulses to operate the electric machine in a pulsed mode to meet the ascertained acceptable level of NVH and the received torque demand, the On-Torque amplitude and duty cycle ascertained at least partially based on whether the internal combustion engine is operating when the torque demand is received; and
operate the electric machine in the pulsed mode, using the series of pulses, the series of pulses having the ascertained On-Torque amplitude and the duty cycle,
wherein the electric machine generates a work output sufficient to meet the torque demand during the series of pulses and substantially no work output between the series of pulses.
39 . The vehicle of claim 38 , wherein the controller is further configured to ascertain the On-Torque demand from one or more other factors besides whether the internal combustion engine is operating, the one or more other factors including:
(a) a gearbox status of a gearbox on the vehicle;
(b) a wheel drive status of a wheel drive system on the vehicle;
(c) a weight of a load carried by the vehicle;
(d) a selectable economy mode feature provided on the vehicle;
(e) a setting of a selectable sport mode feature provided on the vehicle;
(f) a setting of a selectable NVH mode feature provided on the vehicle;
(g) whether or not the vehicle is autonomous or not autonomous, and if autonomous, whether or not the vehicle is occupied by a passenger;
(h) ambient temperature around the vehicle;
(i) a model of NVH characteristics of the vehicle as the vehicle ages;
(j) a model of NVH characteristics of the vehicle after a cold start of the vehicle;
(k) a setting of an active noise control system provided on the vehicle; or
(l) a setting of an active vibration control system provided on the vehicle.