Application Cases

The core of electrostatic levitation technology lies in achieving sample suspension through electric field forces. In experiments, the sample is placed between two electrode plates, and its position is adjusted by controlling the electric field strength between the plates. To accomplish this, the experimental setup is equipped with various advanced optoelectromechanical peripheral devices, including photoelectric sensors, temperature measuring instruments, lasers, CCD cameras, and motors. These devices work in synergy to provide precise measurement and control methods for the experiment.

To enhance the efficiency and convenience of the experiment, the research team developed a comprehensive monitoring software. This software integrates functions such as process control, parameter configuration, data storage, and viewing, significantly simplifying the experimental workflow and allowing researchers to focus more on the experiment itself.

Experimental Equipment: Power amplifiers, photoelectric sensors, temperature measuring instruments, and detectors, among others. These devices play a critical role in the experiment, ensuring the accuracy and reliability of the experimental data.

The power amplifier is one of the key pieces of equipment in the experiment, responsible for providing sufficient voltage to drive the sample’s suspension. The photoelectric sensor is used to monitor the sample’s position in real time, providing precise feedback signals for the control system. The temperature measuring instrument and detector are employed to measure the sample’s temperature and detect other relevant parameters, respectively, ensuring the stability and safety of the experimental process.

Experimental Process:
Stable control of the sample’s suspension position is the core challenge of electrostatic levitation experiments. The experimental process can be divided into three stages: sample charging, detachment from the electrode plate, and stable suspension. At the beginning of the experiment, the sample is placed at the center of the lower electrode plate. As the voltage between the plates gradually increases, the sample begins to exhibit slight tremors. When the voltage continues to rise, the Coulomb force acting on the sample gradually overcomes the effect of the image force, causing the sample to accelerate upward. During this process, the critical role of the control algorithm becomes evident.

To achieve stable suspension of the sample, the experiment employed a feedback control system based on a position-sensitive detector (PSD). The PSD sensor accurately detects the current position of the sample and feeds this information back to the control system. Based on the feedback signals, the control system performs PID calculations to adjust the output voltage of the high-voltage amplifier in real time, thereby altering the electric field strength between the plates and achieving precise control of the sample’s suspension position.

However, the initial stage of sample suspension presents numerous challenges. The sample diameter is only 2 mm, while the distance between the plates is 8 mm. After stable suspension, the distance between the sample and the upper and lower plates is only 3 mm. This requires extremely high precision in position measurement; otherwise, the sample can easily collide with the upper plate shortly after detachment from the lower plate. Additionally, the sample is subjected to the image force from the lower plate during the initial suspension stage, causing it to rise rapidly after detachment, further increasing the difficulty of the control algorithm.

To address these challenges, the experiment adopted an integral separation method. This approach effectively reduces overshoot during the initial stage of sample suspension, improving control stability. Once the sample is stably suspended, the control system automatically adjusts the control parameters to further attenuate oscillations, ensuring stability throughout the suspension process.

Experimental Results:

Figure 2: Image of the Sample in Stable Suspension

The experimental results demonstrate that, through precise control algorithms and advanced experimental equipment, the sample can successfully achieve stable suspension. Figure 2 shows an image of the sample in stable suspension, clearly illustrating its stable state between the upper and lower plates. The image indicates that the sample maintains good stability in both vertical and horizontal directions, with no significant oscillations.

Figure 3: Curves of Position and Voltage Changes During Suspension

Figure 3 displays the curves of position and voltage changes during suspension. By employing the integral separation method, overshoot during the initial stage of suspension was effectively suppressed. After the sample achieved stable suspension, parameter adjustments in the control system further reduced oscillations, ensuring stability throughout the suspension process.

These results indicate that the control algorithms and equipment configurations used in the experiment effectively address various challenges in the sample suspension process, achieving precise suspension control. This achievement not only provides a new experimental approach for materials science research but also lays a solid foundation for the further development of electrostatic levitation technology.

Power Amplifier Recommendation: ATA-7025

Figure: ATA-7025 High-Voltage Amplifier Specifications

This document is compiled and published by Aigtek. For more case studies and detailed product information, please continue to follow us. Xi’an Aigtek has become a large-scale instrument and equipment supplier in the industry with an extensive product line, and all demo units are available for free trial.