On optimization of the pid governor for diesel engine

Abstract

In a diesel engine, governor is indispensable for ensuring that the engine maintains a certain speed under various load conditions, that the engine speed does not exceed a certain speed as a protection against self‐destruction or stall. Also, speed fluctuations resulting from poor governing, lead to vibrations, noise, wear and tear and increased level of soot. Therefore it is desirable to have minimum speed fluctuations under all engine‐operating conditions. Inspite of many limitations, most of the existing engines still use simple mechanical governor providing proportional control only. Electronic governors can provide a more flexible P (proportional), I (integral), and D (derivative) control under all speeds and loads. So far no work is reported on optimizing the controller parameters using the analytical approach. In the present work turbo charged diesel engine is analytically modeled based on Krutov's approach for the control analysis. Attempts have been made to optimize controller parameters. The criterion for minimizing the engine speed fluctuations is met by minimizing the Integral Squared Error in engine speed. The parameters obtained have been used to study the engine speed response. The results have shown remarkable improvement in the engine speed fluctuations.

Dizeliniame variklyje reguliatorius turi palaikyti nustatyta apsisukimu skaičiu prie ivairiu apkrovimo salygu, taip, kad variklio apsisukimu skaičius neviršytu tam tikros ribos, prie kurios variklis genda, arba užgesta. Apsisukimu svyravimai sukelia vibracija, triukšma, nusidevejima, iplyšimus ir padideja suodžiu kiekis. Todel pageidautina esant ivairioms valdymo salygoms tureti minimalius apsisukimu skaičiaus svyravimus. Daugelis eksplo‐tuojamu varikliu, nepaisant nurodytu trūkumu, naudoja paprasta mechanini valdyma, atsižvelgianti tik i proporcingus pokyčius. Šiame darbe turbokompresoriniam dizeliniam varikliui, panaudojus Krutovo analizes metoda sudarytas modelis, kuriame optimizuojami valdymo parametrai. Variklio apsisukimu skaičiaus svyravumu minimizavimui naudojama ju integralines kvadratines paklaidos analize. Gauti parametrai panaudoti variklio reakcijai i apsisukimu greiti nagrineti. Rezultatai rodo žymu variklio apsisukimu skaičiaus svyravimu reguliavimo pagerinima.