摘要 |
<p>Look-up tables 14, 15 of a first control input, such as ignition timing, and a second controlinput, such as fuel demand, are addressed by engine speeds 10a, 13 and load demand 10b to provide base values. A perturbation generator 18 periodially advances and retards ignition timing and the slope of engine speed with respect to ignition timing is compared 20 with a desired slope from a look-up table 16. The slope error is supplied to means 21, 22, 24 for correcting the base values of ignition timing and fuel demand in accordance with a control strategy so that the engine speed slope is corrected to the desired value. In accordance with a first control strategy, one of the control inputs is varied (OC, OD) up to a maximum variation and then the other control input is varied (CE or DF) to correct the engine speed slope. In accordance with a second control strategy, both control inputs are varied simultaneously (OG or OH) with a predetermined relationship between the individual control input variations.</p> |