Temperature Control of Nonlinear Continuous Stirred Tank Reactors Using an Enhanced Nature-Inspired Optimizer and...

Area of Science:

• Process Control Engineering
• Chemical Engineering
• Optimization Algorithms

Background:

• Nonlinear continuous stirred tank reactor (CSTR) temperature control is challenging due to nonlinearities and disturbances.
• Conventional proportional-integral-derivative (PID) controllers often lack the necessary robustness and precision for CSTR systems.
• Advanced optimization techniques are required for effective CSTR temperature regulation.

Purpose of the Study:

• To propose an enhanced joint-opposition artificial lemming algorithm (JOS-ALA) for optimal tuning of fractional-order PID (FOPID) controllers.
• To apply the JOS-ALA tuned FOPID controller to nonlinear CSTR temperature control.
• To evaluate the performance and robustness of the proposed JOS-ALA-FOPID approach against other metaheuristic algorithms.

Main Methods:

• Development of the JOS-ALA by incorporating a joint opposite selection mechanism into the artificial lemming algorithm (ALA).
• Linearization of a nonlinear CSTR model around a stable operating point for controller design.
• Tuning of FOPID controller parameters by minimizing a composite cost function using the JOS-ALA.
• Benchmarking against ALA, EEFO, L-SHADE, iAEFA, and L-SRTDE using extensive simulations.

Main Results:

• The JOS-ALA-tuned FOPID controller achieved superior performance, with the lowest mean cost function value (0.1959).
• The proposed controller eliminated overshoot and achieved a normalized steady-state error of 4.7290 × 10^-4.
• Faster transient response, improved robustness against disturbances and noise, and statistically significant improvements (p < 0.05) were observed.

Conclusions:

• The JOS-ALA provides an effective and reliable optimization framework for high-precision temperature control in nonlinear CSTRs.
• The proposed JOS-ALA-FOPID controller demonstrates superior performance and robustness compared to existing methods.
• The JOS-ALA has strong potential for broader applications in complex process control problems.