Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
121 words
An engine speed control method for controlling engine output torque in accord with an engine torque requirement determined as the torque required to drive engine speed toward a target engine speed, comprising the steps of: storing a predetermined schedule of estimated steady state torque requirement values as a function of a predetermined engine operating condition; determining the current engine operating condition; referencing, from the stored schedule, a current estimated steady state torque requirement as a function of the current engine operating condition; estimating steady state torque requirement error; adjusting the current steady state torque requirement in direction to minimize the estimated steady state torque requirement error; and controlling engine output torque in accord with the adjusted current steady state torque requirement.
Claim 2
Dependent Claim
121 words
An engine speed control method for controlling engine output torque in accord with an engine torque requirement determined as the torque required to drive engine speed toward a target engine speed, comprising the steps of: storing a predetermined schedule of estimated steady state torque requirement values as a function of a predetermined engine operating condition; determining the current engine operating condition; referencing, from the stored schedule, a current estimated steady state torque requirement as a function of the current engine operating condition; estimating steady state torque requirement error; adjusting the current steady state torque requirement in direction to minimize the estimated steady state torque requirement error; and controlling engine output torque in accord with the adjusted current steady state torque requirement.
Claim 3
Dependent Claim
106 words
The method of claim 1, wherein the estimating step further comprises the steps of: providing a schedule of expected values of a predetermined engine operating parameter as a function of engine operating level; determining the current engine operating level; referencing the current expected value of the predetermined engine operating parameter from the provided schedule as a function of the current engine operating level; sampling the current value of the predetermined engine operating parameter; calculating a parameter deviation as a difference between the current expected value and the sampled current value; and estimating steady state torque requirement error as a predetermined function of the calculated parameter deviation.
Claim 4
Dependent Claim
59 words
The method of claim 2, further comprising the step of: calibrating a sensitivity factor representing the sensitivity of engine output torque to a deviation in the predetermined engine operating parameter away from an expected parameter value; and wherein the predetermined function of the calculated parameter deviation is the product of the calculated parameter deviation and the calibrated sensitivity factor.
Claim 5
Dependent Claim
43 words
The method of claim 2, further comprising the steps of: sensing a predetermined steady state engine operating condition; and wherein the sampling step samples the current value of the predetermined engine operating parameter when the predetermined steady state engine operating condition is sensed.
Claim 6
Dependent Claim
95 words
The method of claim 2, further comprising the steps of: developing a stored steady state torque requirement error model by storing the estimated steady state torque requirement error as a function of the sampled current value; and wherein, upon developing the stored steady state torque error model, the step of estimating steady state torque requirement error estimates the steady state torque requirement error by (i) sensing a present value of the at least one engine operating parameter, and (ii) referencing the stored steady state torque requirement error as a function of the sensed present value.
Claim 7
Dependent Claim
19 words
The method of claim 5, wherein the at least one engine operating parameter includes ambient temperature and ambient pressure.
Claim 8
Dependent Claim
17 words
The method of claim 5, wherein the at least one engine operating parameter includes engine coolant temperature.
Claim 9
Dependent Claim
46 words
The method of claim 1, further comprising the step of: sampling present values of a predetermined set of engine parameter signals; and wherein the step of determining the current engine operating condition determines the current engine operating condition as a function of the sampled present values.
Claim 10
Dependent Claim
171 words
An engine speed control method for generating a control command including a steady state torque control command component and a transient torque control command component, the control command applied to an engine output torque control actuator to drive engine speed toward a desired engine speed, comprising the steps of: providing a predetermined schedule of steady state torque control commands representing the torque required for steady state engine speed control, the schedule provided as a function of engine operating level; estimating the current engine operating level; referencing, from the provided schedule, the steady state torque control command as a function of the current engine operating level; estimating steady state torque control command error; determining a command adjustment as a function of the estimated steady state torque control command error; generating the control command as a function of the referenced steady state torque control command and the command adjustment; and applying the control command to the torque control actuator to control engine output torque to drive engine speed toward the desired engine speed.
Claim 11
Dependent Claim
171 words
An engine speed control method for generating a control command including a steady state torque control command component and a transient torque control command component, the control command applied to an engine output torque control actuator to drive engine speed toward a desired engine speed, comprising the steps of: providing a predetermined schedule of steady state torque control commands representing the torque required for steady state engine speed control, the schedule provided as a function of engine operating level; estimating the current engine operating level; referencing, from the provided schedule, the steady state torque control command as a function of the current engine operating level; estimating steady state torque control command error; determining a command adjustment as a function of the estimated steady state torque control command error; generating the control command as a function of the referenced steady state torque control command and the command adjustment; and applying the control command to the torque control actuator to control engine output torque to drive engine speed toward the desired engine speed.
Claim 12
Dependent Claim
108 words
The method of claim 9, wherein the estimating step further comprises the steps of: providing a schedule of expected values of a predetermined engine parameter as a function of engine operating level; referencing, from the provided schedule, the expected value corresponding to the current engine operating level; sensing a predetermined steady state engine operating condition; determining the current actual value of the predetermined engine parameter when the steady state engine operating condition is sensed; calculating a difference between the expected value and the determined current actual value of the predetermined engine parameter; and estimating the steady state torque control command error as a predetermined function of the difference.
Claim 13
Dependent Claim
67 words
The method of claim 10, further comprising the step of: providing a predetermined torque sensitivity factor as the sensitivity of engine output torque to the magnitude of the difference between the expected value of the predetermined engine parameter and the current actual value of the predetermined engine parameter; and wherein the predetermined function of the difference is the product of the torque sensitivity factor and the difference.
Claim 14
Dependent Claim
102 words
The method of claim 9, further comprising the steps of: determining current values of a predetermined set of slowly changing engine parameters; and adapting a stored model of the estimated steady state torque control command error as a function of the determined current values and of the estimated steady state torque control command error; and wherein the estimating step estimates the steady state torque control command error, by (a) sampling a value of the predetermined set of slowly changing engine parameters, and (b) referencing from the stored model a steady state torque control command error as a function of the sampled values.
Claim 15
Dependent Claim
23 words
The method of claim 12, wherein the predetermined set of slowly changing engine parameters includes ambient temperature, ambient pressure, and engine coolant temperature.
Claim 16
Dependent Claim
17 words
The method of claim 8, wherein the engine torque control actuator is an engine intake air valve.