Handheld Partial Discharge Detector (referred to as handheld PD detector) is a portable detection tool used to detect and locate partial discharge phenomena in power equipment. Such instruments typically integrate multiple detection technologies, such as ultrasonic detection and transient earth voltage (TEV) detection, to improve detection accuracy and reliability. Below is an article summary about the handheld PD detector.
Handheld Partial Discharge Detector
Partial Discharge (PD) refers to the small-scale discharge phenomenon occurring in the insulation medium of high-voltage electrical equipment when the electric field strength exceeds the breakdown strength of a local area. This phenomenon may be an early sign of insulation aging or damage in equipment. Handheld partial discharge detectors play an important role in the maintenance and fault prevention of power systems due to their portability and flexibility.
Working Principle
The working principle of the handheld partial discharge detector is based on the multiple physical phenomena that accompany partial discharge, mainly including ultrasound, heat, light, electromagnetic fields, etc. Among them, ultrasound propagates in the form of spherical waves centered on the sound source. The handheld PD detector receives these ultrasonic signals through built-in ultrasonic sensors, and combines other detection methods such as transient earth voltage (TEV) to determine the magnitude and specific location of partial discharge. In addition, the handheld PD detector can display real-time images and data, helping users quickly diagnose the partial discharge status.
Main Functions
Ultrasonic Detection: Uses ultrasonic sensors to receive ultrasonic signals generated by partial discharge.
Transient Earth Voltage (TEV) Detection: Determines whether there is internal partial discharge by detecting transient voltage changes on the equipment enclosure.
Multi-sensing Intelligent External Sensor: Receives high-frequency ultrasonic signals, analyzes partial discharge radiation and generated UHF and ultrasonic signals.
Signal Processing: Uses special algorithms and advanced signal processing techniques to improve detection accuracy.
Real-time Display: Displays detection results on the screen, including discharge pulse waveform, amplitude, etc.
Location Function: Achieves precise location of partial discharge sources through multi-point detection and comparison.
Data Recording and Analysis: Records detection data for subsequent analysis and report preparation.
Usage Steps
Startup Preparation: Set the basic parameters of the instrument according to the manual instructions.
Signal Check: Ensure that a slight, uniform electrical noise is heard in the earphones, and the curve drawing area on the test interface shows the center line aligned to 0dB, with the average value below 10dB.
Scanning Detection: Hold the instrument facing the switchgear cabinet and perform a low-speed uniform scanning detection. When a PD signal is detected, an obvious discharge sound can be heard through the earphones, while the amplitude curve on the screen rises, and both the average and maximum values increase.
Locating Discharge Points: Perform repeated measurements from different angles on the tested position to eliminate environmental noise interference, and use the laser locator built into the PD detector to determine the specific location of the discharge point.
Saving Results: After confirmation, click the save button on the device screen to store the test results at that moment.
Setting Parameters: According to needs, parameters such as output voltage, units, reading settings, discharge count, and sensors can be set.
Adjusting Trigger Mode: By default, the multifunctional PD tester host selects the "Auto" mode. When the multifunctional PD tester host does not detect a trigger within a certain period, it forces a trigger.
Application Fields
Power Generation Enterprises: Used to detect the insulation status of key equipment such as generators and transformers.
Power Supply Systems: Applied to substations, distribution rooms, and other facilities to monitor cables, switchgear, and other equipment.
Petrochemical Enterprises: Used to detect high-voltage equipment such as large motors and transformers.
Railway Power Systems: Used for maintenance of facilities such as rail vehicles and traction substations.
Aerospace: Used to detect high-voltage components in equipment such as aircraft and satellites.
Maintenance and Care
Check Power Supply: When the terminal is energized but the handheld PD detector cannot start normally, check whether the fuse on the power socket is intact.
Moisture and Shock Protection: When used outdoors, try to avoid direct sunlight and humid environments to prevent damage to the instrument.
Cleaning and Maintenance: Regularly clean the instrument surface, especially the sensor part, to avoid dust affecting detection accuracy.
Regular Calibration: Calibrate the instrument according to the time intervals recommended by the manufacturer to ensure the accuracy of detection results.
Conclusion
The handheld partial discharge detector is one of the important tools in power system maintenance. It helps engineers detect and solve potential partial discharge problems in a timely manner, thereby improving the reliability and safety of the power system.
References
China Chemical Instrument Network: Technical parameters of GCJF 901 handheld remote ultrasonic partial discharge patrol locator.
Yangzhou Tuopu Electrical Technology Co., Ltd.: Introduction to handheld ultrasonic partial discharge patrol locator.
Toutiao: The function and role of HDJF-9001 handheld remote ultrasonic partial discharge patrol locator.
Bafang Resource Network: Detailed page of MD9001 handheld ultrasonic partial discharge patrol locator.
Wuhan Kaidi Zhengda: Related information on KDJF-800 partial discharge tester.
Yangzhou Darui: Product description of ultrasonic partial discharge patrol locator.
