Journal of Mechanical Engineering and Transport

The main characteristics that determine the state of the power unit are the power level and torque. These parameters affect the dynamic qualities of the car and can also play a role in fuel consumption and emission levels. 
To check these characteristics, traction roller stands of the inertial type are used. These stands allow you to simulate real traffic conditions and loads. Usually, on such stands, the traction force on the driving wheels is measured, which makes it easy to calculate the power in certain driving modes. 
However, creating a full-fledged load on the driving wheels of the car being diagnosed requires the use of powerful loading and driving devices. This significantly increases the cost of the stand and its metal content. 
An alternative to this method is the compressed acceleration method. In this method, the load is created by a relatively small inertial mass together with a loading and driving device of moderate power. The diagnostic parameter in this method can be traction force on the wheels, acceleration, time or path of acceleration of the wheels in the selected speed range. For measurement accuracy, it is better to use acceleration time. However, all the advantages of the method can be manifested only with the correct choice of test modes. During testing, results depend on the accuracy and stability of maintaining the test mode. Acceleration time will be measured more accurately, the slower the wheels and rollers of the stand accelerate. During the tests, it is necessary to choose the high-speed measurement mode to ensure a sufficiently stable torque value. 
The article analyzes the acceleration modes of a car on a roller stand and their influence on the accuracy of diagnostics. The smallest error is achieved when measuring acceleration time from 50 to 70 km/h in IV gear with additional load or in V gear without load

References