Multi-mode fuzzy control strategy of PCR precision temperature control system.

Aiming at the problem of slow temperature rise and fall of PCR instrument and unstable working status, a cross-control method of fuzzy algorithm and proportional integral derivative algorithm is proposed. Through the analysis of heat conduction theory, the dynamic differential equation and transfer function of heat conduction in the medium are established; according to the transfer function, through the Ziegler-Nichols (Ziegler-Nichols, ZN) law, using PIDtuner auxiliary calculation, a design is designed High-precision PID controller; adopting seven-level domains, and designing a kind of fuzzy controller with high robustness through online adjustment of quantization factors and scaling factors α, β, and γ; through temperature deviation e(t) and The deviation change rate de(t) change amount is compared, and the controller\u0027s working state is switched in real time, which realizes the multi-modal fuzzy PID control method. Using sinmulink for simulation, the heating rate is ≥8℃/s, and the cooling rate is ≥6℃/s. After the system is stable, the error is reduced to ±0.01℃, which fully meets the requirements of the PCR instrument temperature control system.