Scania Cv Ab

Martin Evaldsson

Fredrik Roos

Oskar Johansson

Karl Redbrandt

Maria Södergren

Niclas Lerede

Elvedin Ramic

Arvid Rudberg

Robin Rockström

Johan Tunhag

Mikael ÖGren

A method for limitation of torque build-up of an engine () in a motor vehicle (), including the steps of continuously identifying (s) a pattern pertaining to a maximum permissible torque (Tqmax); responding to torque demand (s) by guiding torque build-up towards desired torque (Tqreq); responding to torque demand by continuously determining (s) a difference (Tqdiff; Tqdiffnorm) between maximum permissible torque (Tqmax) and a prevailing torque (Tq); and controlling the torque build-up (s) so that the resulting torque (Tq) is a function of the continuously determined difference (Tqdiff; Tqdiffnorm). Also a computer program product containing program code (P) for a computer () for implementing a method according to the invention. Also a device that performs the method and a motor vehicle () equipped with the device are disclosed.

Method and device for limiting the torque build-up of an engine

A desired change of a time derivative of dynamic torque (Tq), provided to an output shaft from an engine in a vehicle, from a current value to a new desired value is determined. A current rotational speed difference (&#x394;&#x3c9;) is determined between a first end of the powertrain in a vehicle, which rotates with a first rotational speed (&#x3c9;), and a second end of the powertrain, which rotates with a second rotational speed. The first rotational speed (&#x3c9;) is then controlled on the basis of the desired value of the time derivative for the dynamic torque (Tq), a spring constant (k) related to a torsional compliance in the powertrain, and the determined current rotational speed difference {&#x394;&#x3c9;). Through control of the first rotational speed, the current value for the time derivative for the dynamic torque is also indirectly controlled towards the desired value.

Torque control of a vehicle powertrain based on a time derivative for a dynamic torque

A method and a system for control of a torque Tqrequested from an engine in a vehicle, wherein the engine provides a dynamic torque Tqin response to the torque Tq. Control of the requested torque Tqis performed such that the control provides a desired value Tqfor the dynamic torque and/or a desired derivative Tqfor the dynamic torque. This is achieved by basing the control on at least one current value Tqfor the dynamic torque, on one or several of the desired value Tqand the desired derivative Tqfor the dynamic torque, and on a total delay time telapsing from determination of at least one parameter value, to when a change of the dynamic torque Tqbased on the determined at least one parameter value, has been effected.

Control of a torque demanded from an engine

Disclosed is a system for regulation of torque demanded from a prime mover of a vehicle, which prime mover responds to the torque demanded by delivering a dynamic torque. This dynamic torque is related by a gear ratio to a dynamic wheel torque which a power train comprising the prime mover imparts to at least one tractive wheel of the vehicle. The system regulates the torque demanded in such a way that a difference between the torque demanded and the dynamic torque is actively limited by employing feedback of the dynamic torque at an earlier time. The torque demanded at a time (t) for the regulation is limited to a maximum value which exceeds the dynamic torque at an earlier time by an offset value. The torque demanded is continuously varied according to the dynamic torque, so that power train oscillations in the vehicle are reduced in number and/or magnitude.

Control of a requested torque in a vehicle

The present invention provides a system for the control of an actual speed for a vehicle, wherein the system is arranged to be able to carry out the control based on a manual control of the actual speed or based on an automatic control of the actual speed. According to the present invention, an automatic control device is arranged to permit that the automatic control may actively control the actual speed to a higher value than a manual control device is arranged to permit the manual control to actively control the actual speed to.

Method for controlling an actual speed of a vehicle

A method and a system for determining a running resistance Ffor a vehicle. A model-based running resistance Fis estimated. Thereafter an energy change difference &#x394;Wbetween a model-based estimated energy change &#x394;Wand an actual energy change &#x394;Wis determined for the vehicle from a starting point to an end point of a distance S which is traveled by the vehicle. A braking force Fwhich is unknown to the model and which acts upon the vehicle over the distance S is also determined on the basis of the energy change difference &#x394;W. Thereafter the running resistance Fis determined to an adjusted value of the model-based estimate of the running resistance F, the adjustment being based on the braking force Fwhich is unknown to the model.

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Nacka, Sweden

Martin Evaldsson