Material challenges and countermeasures under voltage stress

Voltage stress is the force exerted by an electric field on conductor or insulator materials in electronic components, circuits, or electrical equipment. Simply put, when an electric field passes through a material, the electric field force causes strain within the material, thereby forming voltage stress. It is usually expressed in the form of force (stress) per unit area, with units of Pascal (Pa) or MegaPascal (MPa).

Calculation method of voltage stress
To calculate voltage stress, two important concepts need to be understood: electric field strength and electric displacement.
1. Electric Field Intensity: Electric field intensity is the force exerted by a unit positive charge. It is represented by the density of electric field lines and has direction in space. The symbol is E and the unit is volt/meter (V/m).
2. Electric Displacement: Electric displacement is the total amount of charge that causes an electric field in a medium. It is related to the contribution of free charges and polarized charges. The symbol is D and the unit is Coulomb/square meter (C/m²).

Calculation formula of voltage stress
According to the definition of voltage stress and the concept of electric field strength, the voltage stress can be calculated using the following formula: Voltage stress = Electric field strength × dielectric constant of the material.
Among them, the dielectric constant of a material refers to the material's ability to respond to an electric field. Different materials have different dielectric constants, so under the same electric field intensity, different materials will produce different voltage stresses.

Effect of voltage stress on materials
Voltage stress can cause a variety of electrical problems and structural failures, including:
1. Insulation destruction: High voltage stress may cause breakdown of insulating materials, allowing current to pass through the insulator, causing electrical failure.
2. Dielectric polarization: Voltage stress can cause polarization in the dielectric, causing charges to be redistributed within the material, generating additional electric fields and electric displacements, affecting circuit performance and signal transmission.
3. Electrical corrosion: Under high voltage stress, electric current may cause oxidation, corrosion and ablation of metal surfaces, damaging electronic components or circuits.
4. Structural failure: Voltage stress may cause stress concentration inside the material, causing the material to deform, crack or break, leading to structural failure.

Safety Measures for Voltage Stress
To reduce the impact of voltage stress on materials and structures, the following safety measures can be taken:
1. Select appropriate materials: Materials with higher voltage resistance and good insulation properties should be selected to resist voltage stress.
2. Add an insulation layer: When higher voltage withstand capability is required, an insulation layer can be added to provide additional protection.
3. Good grounding and shielding: can reduce the spread and interference of voltage stress and reduce voltage gradient.
4. Voltage distribution: Evenly distribute high voltage to multiple parts to reduce voltage stress in a single area.
5. Follow standards and specifications: Refer to specifications such as rated voltage and operating temperature of the materials used.
6. Regular maintenance: Perform regular maintenance and inspections on equipment and circuits that have been exposed to high voltage stress for a long time, repair potential problems in a timely manner, and avoid failures and damage.