# Research on the speed fluctuation control of diesel engine under load changes via an improved sparrow algorithm

## TL;DR

This paper introduces an improved sparrow search algorithm to enhance diesel engine speed control, reducing adjustment time and overshoot under load changes.

## Contribution

The novel contribution is the improved sparrow search algorithm used to optimize FPID control for diesel engines.

## Key findings

- FPID control reduces adjustment time by 1.4s and overshoot by 6.8% at 2000 RPM.
- Speed stabilization time under load changes is reduced by 18% and 30% for loads 8 and 10.
- Speed fluctuation deviation is reduced by 7% and 12% for the same load changes.

## Abstract

Given the nonlinear and time-varying characteristics of diesel engine speed control, a conventional proportional integral derivative (PID) controller is inadequate for addressing the lag or overshoot in the system response, and it struggles to adapt to complex dynamic changes under load. This study proposes a fuzzy proportional integral derivative (FPID) control,which is based on an improved sparrow search algorithm(ISSA) with the aim of enhancing the system’s adaptability. By refining the algorithm to augment its parameter control capabilities and employing test functions for experimental comparisons, the improved algorithm exhibited accelerated convergence and increased accuracy. The improved sparrow search algorithm is applied to two controllers for experimental comparison, and the results indicate that, in contrast to the traditional PID control algorithm, the FPID control algorithm reduces the adjustment time by 1.4 s and decreases the overshoot by 6.8% when the speed is adjusted to 2000 revolutions per minute (RPM). The duration for speed fluctuation stabilization under load changes of 8 and 10 is decreased by 18% and 30%, respectively, and the fluctuation deviation of the speed is reduced by 7% and 12%, respectively. Consequently, the implementation of FPID parameters tuned by the improved sparrow algorithm provides robust support for the stable operation of a diesel engine during speed fluctuations.