Application Cases

Experiment Name: Hysteresis Loop and Breakdown Field Strength Testing of Polyetherimide Films

Research Direction:
In response to global energy shortages, climate change, and atmospheric pollution, new energy power generation technologies such as solar, wind, and thermal energy have emerged. However, due to the intermittent and unstable nature of renewable energy generation, it is challenging to integrate directly into large power grids. Thus, there is an urgent need for large-scale power conversion and energy storage devices. Additionally, pulse power technology, electromagnetic catapult systems, high-voltage flexible direct current transmission, and electric vehicle technology have all placed pressing demands on high-power-density energy storage devices.

Polymer-based dielectric capacitors, as high-power-density energy storage devices, are widely used in industries such as renewable energy, pulse power, power electronics, and high-voltage direct current transmission. Currently, commercially available polymer capacitor films often occupy significant volume in equipment due to their relatively low dielectric constants and energy storage densities. On the other hand, as electrical insulation technology advances toward higher temperatures, the operating temperature requirements for dielectric film capacitors are also increasing. Therefore, researching high-energy-density thin-film dielectrics suitable for high-temperature environments holds significant scientific research importance and practical application value for achieving miniaturization, lightweight design, and integration of energy storage capacitors in pulse power and power electronics equipment.

Capacitors typically consist of dielectric materials and two conductive electrodes in a parallel-plate configuration, as shown in Figure 1.4. Energy storage is a fundamental function of capacitors, and their energy storage capacity (i.e., capacitance) is determined solely by the physical dimensions (geometry) of the conductors and the dielectric constant of the material, independent of the potential difference between the conductors or the total charge on them. To address the relatively low dielectric constants of polymer dielectrics, various types of nanofillers have been introduced into polymers over the past few decades to prepare polymer-based nanocomposites. Thus, researching high-energy-density thin-film dielectrics suitable for high-temperature environments is crucial for advancing the miniaturization, lightweight design, and integration of energy storage capacitors in pulse power and power electronics equipment.

Experiment Objective:
To conduct hysteresis loop testing and breakdown field strength testing of PEI-based composite energy storage dielectrics with different nanofillers, providing a foundation and validation for subsequent experiments.

Testing Equipment:
ATA-7100 High-Voltage Amplifier, Signal Generator, Oscilloscope

Experimental Procedure:
First, a unipolar triangular wave signal with a frequency of 10 Hz is generated by the function generator. The signal is then amplified by the ATA-7100 high-voltage amplifier and applied across the sample. The output voltage can be controlled via the amplifier's gain knob, while its magnitude is monitored using the oscilloscope. This amplifier is capable of outputting both AC and DC signals, with a maximum AC output of 20 kVpp and a maximum DC output of 10 kV, making it suitable for breakdown field strength testing. The schematic diagram of the testing setup is shown in Figure 1-1.

Figure 1-1: Block Diagram of Breakdown Field Strength Testing and Hysteresis Loop Testing

Experimental Results:
The DC breakdown field strength test results of PEI-based nanocomposite dielectrics with different nanofillers are shown in Figure 1-2, which presents the Eb and β values for these materials. As the nanofiller content increases, the Eb values of the PEI-based nanocomposite dielectrics with different fillers initially rise and then decline. At a filler content of 3 vol%, the PEI/SiO₂ and PEI/ZrO₂ nanocomposite dielectrics achieve their maximum Eb values of 595 MV/m and 610 MV/m, respectively. The PEI/TiO₂ nanocomposite dielectric reaches its maximum Eb value of 524 MV/m at a filler content of 1 vol%.

Furthermore, compared to the β value of pure PEI (8.24), the β values of the PEI-based nanocomposite dielectrics with different nanofillers also increase. At a filler content of 3 vol%, the β values for PEI/SiO₂, PEI/ZrO₂, and PEI/TiO₂ nanocomposite dielectrics are 8.98, 12.66, and 8.57, respectively. Notably, the β values for PEI/ZrO₂ nanocomposite dielectrics across all filler contents exceed 10, reflecting their high breakdown stability.

Figure 1-2: Two-Parameter Weibull Distribution Plot of Breakdown Field Strength for PEI-Based Composite Dielectrics with Different Filler Contents

Product Recommendation: ATA-7100 High-Voltage Amplifier

Figure: ATA-7100 High-Voltage Amplifier Specifications

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