Control of pressure in ion nitriding based on L298N chip

Abstract: The ion nitriding process demands precise pressure control within the furnace. This paper presents a gas flow controller designed using the L298N chip to drive a DC motor, enabling accurate regulation of the pumping gas flow in the reaction furnace and improving overall pressure control. This system not only enhances the accuracy of the process but also reduces production costs significantly.

1. Ion Nitriding Theory Ion nitriding is performed in a low-temperature plasma environment. A low-pressure gas is ionized by an electric field, generating high-energy ions and neutral atoms. These particles improve the microstructure of the surface layer, accelerate chemical reactions, and promote the formation of a nitrided layer. Ion nitriding occurs through a glow discharge process. During this process, the furnace pressure must be controlled with high precision, as even small deviations—measured in tens of Pascals—can impact the results. According to Paschen’s Law:

Where: - $ P $ is the gas pressure, - $ d $ is the distance between parallel plate electrodes, - $ V $ is the cathode secondary electron emission coefficient, - $ B $ is the Stolz constant, - $ A $ is a constant. From equation (1), we can derive the breakdown voltage expression (2):

As shown in equation (2), the breakdown voltage $ V $ depends on both the gas pressure $ P $ and the electrode distance $ d $. In most experiments, $ d $ remains fixed, making pressure control crucial for successful ion nitriding. 2. System Flow and Pressure Measurement and Control Block Diagram The flow meter regulates the intake gas flow rate. When the intake and exhaust flow rates are balanced, the furnace pressure remains stable. However, due to gas leakage and other disturbances, the pressure may fluctuate, causing the system to deviate from equilibrium and negatively affecting plasma processing. To address this, a common DC motor is used, driven by the L298N chip. The motor rotates a cone via a reduction lever. As the cone rotates, it adjusts the amount of gas extracted by the aspirator—either increasing or decreasing it to maintain the desired furnace pressure. A pressure sensor measures the furnace pressure, and the signal is sent to a transmitter, which provides feedback to the gas flow controller. This allows for real-time adjustment and maintains stable conditions. An electric vacuum butterfly valve is typically used at the suction port, but it is costly. Instead, the proposed system offers a more cost-effective solution. Figure 1 illustrates the block diagram of the system.

Figure 1: System flow and pressure measurement and control block diagram

3. Introduction to the L298N Chip

Figure 2: Internal function modules of the L298N chip

The L298N is a dual H-bridge motor driver that can control two DC motors simultaneously. It supports a wide range of voltages and currents, making it suitable for various applications. Its internal structure includes power transistors, logic circuits, and protection mechanisms, ensuring reliable operation under different load conditions. By integrating the L298N into the control system, the gas flow can be precisely adjusted, contributing to better pressure stability in the ion nitriding process.

Hybrid Light Tower

Hybrid light tower

A hybrid light tower is a type of lighting system that combines traditional lighting technologies, such as high-intensity discharge (HID) lamps, with renewable energy sources, such as solar panels and wind turbines. This combination allows the light tower to operate independently of the electrical grid, making it a more sustainable and cost-effective lighting solution.
The hybrid light tower typically consists of a tall tower structure with multiple light fixtures mounted at the top. The tower is equipped with solar panels and/or wind turbines, which generate electricity from the sun and wind. This electricity is stored in batteries or used directly to power the light fixtures.
During the day, the solar panels collect sunlight and convert it into electricity, which is stored in batteries for use during the night or in cloudy conditions. The wind turbines generate electricity when there is sufficient wind, further contributing to the power supply.

Hybrid light tower is an advanced lighting tower, it can save 40% fuel, save maintenance, save labor. It operates from the latest solar and battery combination, backed up by a small fuel-efficient diesel engine. Utilizing latest, hybrid technology, provide less consumed power than traditional towers for huge fuel savings and reduced COâ‚‚ output.

Hybrid Light Tower,Hybrid Solar Mobile Light Tower,Hybrid Solar Light Tower,Solar Mobile Light Tower

Grandwatt Electric Corp. , https://www.grandwattelectric.com