In the precise machine of the power system, every ‘member’ shoulders a crucial mission. And the , like a meticulous “health inspector” of power equipment, helps us understand the “health status” inside the equipment through precise measurement. How does this’ medical examiner ‘work? What aspects are closely related to us?
What is dielectric loss?
Simply put, dielectric loss refers to the phenomenon of energy loss inside a dielectric under the action of an electric field. In power equipment, insulation materials serve to isolate high-voltage conductors from the casing and prevent electrical leakage. However, insulation materials are not perfect. When a voltage is applied, an electric field is generated inside the dielectric, and a portion of the electrical energy is converted into thermal energy and dissipated, which is known as dielectric loss. The increase in dielectric loss usually indicates the aging, moisture or deterioration of insulation materials, which is an important signal of potential equipment failure.
The ‘behind the scenes’ driving force that affects dielectric loss
Temperature: The dielectric constant and loss tangent of insulating materials usually increase with increasing temperature.
Humidity: Moisture is the “killer” of insulation materials, which significantly increases dielectric loss, especially in forming conductive pathways on the surface.
Electric field strength: In some cases, excessively high electric field strength can also cause partial discharge and increase dielectric loss.
The material itself: The type, production process, and aging degree of insulation materials will directly affect the level of dielectric loss.
Our ‘Medical Examiner’ – Dielectric Loss Tester
HV Hipot Electric Co., Ltd., as a leader in the industry, has developed and produced a that can accurately measure the dielectric loss tangent (tan δ) and capacitance (C) of insulation materials for high-voltage power equipment such as transformers, transformers, and cables. These data are valuable basis for us to judge the insulation performance of equipment, predict faults, and develop maintenance plans.
What is the measurement process like?
Using a for measurement typically involves the following steps:
Connecting devices: Connect the tester to the corresponding wiring terminals of the tested device (such as a transformer).
Set parameters: Based on the device type and voltage level, set parameters such as test voltage and frequency on the tester.
Measurement: Start the tester, and the instrument will automatically apply voltage and measure the phase difference between current and voltage to calculate the dielectric loss tangent.
Analysis results: Compare the measured data with the equipment’s factory standards or historical data to determine the insulation status.
Why pay attention to dielectric loss?
Early fault diagnosis: Abnormal increase in dielectric loss is often a signal of early damage inside the equipment, which can help us prevent it in advance.
Evaluating insulation life: Continuous monitoring of dielectric loss can effectively assess the aging degree of insulation materials and predict the remaining life of equipment.
Equipment status monitoring: It is an important part of the equipment status monitoring system, providing critical data support for the safe operation of equipment.
How can we do better?
Regular testing: Establish a comprehensive regular testing system and arrange regular dielectric loss tests based on equipment operating time and importance.
Multi point measurement: For large equipment, multi-point measurement can be performed at different leads or voltage levels to obtain more comprehensive information.
Combined with other tests: Combining dielectric loss testing with other electrical tests (such as DC resistance and insulation resistance testing) can more accurately evaluate the overall insulation performance of the equipment.
The professional equipment of HV Hipot Electric Co., Ltd. provides us with reliable measurement guarantee. Through in-depth understanding of insulation materials and professional application of equipment health diagnosis, we can more effectively ensure the safe and stable operation of the power system.
Frequently Asked Questions (FAQ)
Q: What electrical equipment is themainly used to measure? Answer: Mainly used for measuring power equipment such as transformers, mutual inductors, cables, high-voltage switches, generators, etc.
Q: Is it better for the “tan δ” value of the dielectric loss test to be larger or smaller? Answer: The smaller the tan δ value, the smaller the dielectric loss and the better the insulation performance.
Q: Why does temperature affect the measurement results of dielectric loss? Answer: An increase in temperature will intensify the molecular motion inside the insulation material, leading to an increase in energy loss, that is, an increase in dielectric loss.
Q: Is it necessary to power off the equipment during dielectric loss testing? Answer: Yes, for safety and accurate measurement, it is usually necessary to power off the equipment.
Q: What is the difference between dielectric loss testing and insulation resistance testing? Answer: Insulation resistance testing mainly reflects the static resistance value of insulation, while dielectric loss testing focuses more on reflecting the dynamic loss of insulation materials under alternating electric fields, which can better reflect the degradation trend of insulation.