Technical Report: Smart Quad-Peltier Thermal Management System

1. Executive Summary

This report details the implementation of a solid-state cooling system using four TEC1-12706 Peltier modules. The system is designed to provide active thermal management for a refrigeration compressor and its auxiliary water reservoir, managed by an ESP32 microcontroller through a sequential logic control loop.

2. System Architecture & Components

The system is divided into two specialized cooling zones:

Zone A (Compressor Stabilization): Two Peltier modules mounted on the compressor housing to prevent overheating and maintain oil viscosity.

Zone B (Process Water Cooling): Two Peltier modules submerged or attached to the water tank to pre-chill the evaporative cooling water.

Control Hub: ESP32 MCU utilizing high-current IRFZ44N MOSFETs as electronic switches.

Power Source: 12V DC / 30A High-Capacity Power Supply.

3. Sequential Operational Logic (Step-by-Step)

In accordance with the sequential processing nature of the microcontroller, the system operates in a continuous, high-speed loop. The command execution follows this precise order:

Step 1: Data Acquisition (Input 1)

The MCU queries the DS18B20 digital sensor located on the compressor casing.

Step 2: Logic Evaluation & Zone A Activation

If $T_{compressor} > \text{Threshold}$, a PWM signal is sent to MOSFET 1. This activates the first pair of Peltier modules.

Step 3: Data Acquisition (Input 2)

Immediately after, the MCU queries the sensor located in the water reservoir.

Step 4: Logic Evaluation & Zone B Activation

If $T_{water} > \text{Threshold}$, a PWM signal is sent to MOSFET 2, activating the second pair of Peltier modules.

Step 5: Loop Recycling

The sequence resets. Due to the high clock speed of the ESP32, this sequential processing ensures real-time responsiveness across both cooling zones.

4. Key Performance Benefits

Active Thermal Protection: Prevents compressor "Overload" shutdowns during extreme ambient heat (50°C+).

Improved COP (Coefficient of Performance): By pre-cooling the spray water, the refrigerant condensation pressure is lowered, reducing the overall power consumption of the compressor.

Sequential Reliability: By separating the activation commands, the system avoids sudden current spikes on the power supply, ensuring longer lifespan for the electronic components.

5. Technical Conclusion

The integration of a Quad-Peltier array provides a specialized layer of thermal protection that traditional refrigeration systems lack. By focusing the Peltier modules on heat-critical areas, the system ensures maximum reliability without interfering with the primary refrigerant cycle

cycle.