When using a generic engine block, why does it seems to work only when it is given some initial velocity in SimDriveline 2.2

When the velocity of a Generic Engine drops below the Stall Velocity which is specified in its block properties, the engine stalls. As a result, specifying an initial velocity which is less than the engine's stall velocity results in a stall.

How can a user start the engine with zero initial velocity, then "start the engine" at some point in time.

Answer 1

[MathWorks Support Team]

This is expected behavior. The workaround is to use a "Signal Builder" block with an "Ideal Torque Source" to generate a impulse torque which can spin the Generic Engine to a velocity which is greater than the stall speed. If the throttle is on at this point, it will maintain the engine's velocity.

The included model called "sdl_vehicle_starter" starts from no throttle and an engine stall, applies a throttle at t = 60 seconds, and then initiates the starter motor via the Ideal Torque Source at t = 90 seconds.

NOTE: From R2013a onwards Generic Engine in SimDriveline has new feature of Idle speed control, through which the same functionality can be achieved without the additional Torque Source:

https://www.mathworks.com/help/releases/R2020a/physmod/sdl/ref/genericengine.html

-> Idle Speed Control -> Enable idle speed controller