Abstract: The present invention relates to a method for use in dynamometer testing of a vehicle powertrain component or a vehicle (100), a dynamometer power source (201) of a vehicle dynamometer system being connected to an output shaft of a vehicle powertrain component or a vehicle wheel shaft, said dynamometer system being arranged to measure a reaction load and said method including, when testing: determining a first measure of a first reaction load of said first dynamometer power source, determining an influence of moment of inertia on said first measure of said first reaction load, and compensating said first measure of said first reaction load by said determined influence of moment of inertia.

Abstract: The present invention relates to a method for use in dynamometer testing of a vehicle (100), the vehicle (100) including at least a first wheel shaft and at least one first vehicle power source for providing power to said first wheel shaft, said first wheel shaft being connected to a vehicle dynamometer system, said vehicle dynamometer system comprising a first controllable dynamometer power source (201) for providing power to said first wheel shaft, said first dynamometer power source being an electrical machine (201) comprising a stator and a rotor, said stator comprising a stator winding. The method includes: determining whether a first temperature (T1) is below a first temperature limit (Tlim1), and heating said electrical machine (201) by applying a current (Iheat) to said stator winding when said first temperature (T1) is below said first temperature limit (Tlim1).

Abstract: The present invention relates to a method for measuring the content of at least one compound in an exhaust gas stream resulting from internal combustion. A first relative proportion of a first compound in the exhaust gas stream is measured by means of a first sensor, and a defined flow of a first gas is added to said exhaust gas stream downstream said first sensor. A second relative proportion of said first compound in the combined stream of said exhaust gas stream and said added gas is measured by means of a second sensor, and a mass flow of said first compound in said exhaust gas stream resulting from said combustion in said internal combustion is determined by means of said first and second relative proportions and said defined flow of said first gas. The invention also relates to a system and vehicle dynamometer.

Abstract: The present invention relates to a method for use in dynamometer testing of a vehicle powertrain component or a vehicle (100), a dynamometer power source (201) of a vehicle dynamometer system being connected to an output shaft of a vehicle powertrain component or a vehicle wheel shaft, said dynamometer system being arranged to measure a reaction load and said method including, when testing: determining a first measure of a first reaction load of said first dynamometer power source, determining an influence of moment of inertia on said first measure of said first reaction load, and compensating said first measure of said first reaction load by said determined influence of moment of inertia.

Abstract: The present invention relates to a method for use in dynamometer testing of a vehicle (100), the vehicle (100) including at least a first wheel shaft and at least one first vehicle power source for providing power to said first wheel shaft, said first wheel shaft being connected to a vehicle dynamometer system, said vehicle dynamometer system comprising a first controllable dynamometer power source (201) for providing power to said first wheel shaft, said first dynamometer power source being an electrical machine (201) comprising a stator and a rotor, said stator comprising a stator winding. The method includes: determining whether a first temperature (T1) is below a first temperature limit (Tlim1), and heating said electrical machine (201) by applying a current (Iheat) to said stator winding when said first temperature (T1) is below said first temperature limit (Tlim1).

Abstract: A dynamometer test unit for use in dynamometer testing of a vehicle, where the vehicle includes at least a first wheel shaft and at least one first vehicle power source for providing power to the first wheel shaft. The first wheel shaft is, during testing, connected to a dynamometer test unit which includes a first individually controllable dynamometer power source for applying a first power to the first wheel shaft. The dynamometer test unit further includes a second individually controllable dynamometer power source for applying a second power to the first wheel shaft. The first and the second dynamometer power source apply a controllable power to the first wheel shaft during testing. The invention also relates to a dynamometer test system.

Abstract: The present invention relates to a method for measuring the content of at least one compound in an exhaust gas stream resulting from internal combustion. A first relative proportion of a first compound in the exhaust gas stream is measured by means of a first sensor, and a defined flow of a first gas is added to said exhaust gas stream downstream said first sensor. A second relative proportion of said first compound in the combined stream of said exhaust gas stream and said added gas is measured by means of a second sensor, and a mass flow of said first compound in said exhaust gas stream resulting from said combustion in said internal combustion is determined by means of said first and second relative proportions and said defined flow of said first gas. The invention also relates to a system and vehicle dynamometer.

Abstract: Dynamometer testing of a vehicle comprising, with only a first wheel shaft connected to a dynamometer test unit, including the steps of applying a first power to the first wheel shaft, determining a representation of the first power using the dynamometer test unit, determining a second power, different from the first power, being applied to one or both of the first wheel shaft and the second wheel shaft, the second power being a virtual power represented by a virtual representation of second power, and, based on the representation of the first power determined by the dynamometer test unit and the virtual representation of the second power, determining a first speed which is a representation of the speed of the vehicle driven on a road and subjected to the first and second power.