Abstract: Provided are an imaging method and system for residual stress of a basin insulator and a method for preparing a test block. The imaging method includes cutting and preparing a standard industrial sample of a basin insulator and testing the acoustoelastic coefficient of the standard industrial sample; then obtaining the residual stress data of the basin insulator and obtaining the spatial point sound velocity distribution of the basin insulator; finally, obtaining a stress distribution cloud map of the basin insulator by calculation of the attribute value and the coordinate data of a to-be-measured location, and performing reliability verification based on the residual stress data.

Abstract: Provided are an imaging method and system for residual stress of a basin insulator and a method for preparing a test block. The imaging method includes cutting and preparing a standard industrial sample of a basin insulator and testing the acoustoelastic coefficient of the standard industrial sample; then obtaining the residual stress data of the basin insulator and obtaining the spatial point sound velocity distribution of the basin insulator; finally, obtaining a stress distribution cloud map of the basin insulator by calculation of the attribute value and the coordinate data of a to-be-measured location, and performing reliability verification based on the residual stress data.

Abstract: Defect detection method for a semi-conducting bedding layer of a power cable includes: obtaining a length parameter, a corrugation pitch parameter, radius parameters, and a thickness parameter of a power cable; obtaining a first resistance value between a shield and a corrugated sheath, and calculating a second resistance value of the shield based on the length parameter and the corrugation pitch parameter; calculating a radial resistance value of the semi-conducting bedding layer based on the first resistance value and the second resistance value; determining a contact angle of a critical point of contact between the corrugated sheath and the semi-conducting bedding layer based on the radius parameters and the thickness parameter; calculating volume resistivity of the semi-conducting bedding layer based on the radial resistance value and the contact angle; and comparing the volume resistivity with a preset evaluation parameter to obtain a defect detection result of the semi-conducting bedding layer.

Abstract: Defect detection method for a semi-conducting bedding layer of a power cable includes: obtaining a length parameter, a corrugation pitch parameter, radius parameters, and a thickness parameter of a power cable; obtaining a first resistance value between a shield and a corrugated sheath, and calculating a second resistance value of the shield based on the length parameter and the corrugation pitch parameter; calculating a radial resistance value of the semi-conducting bedding layer based on the first resistance value and the second resistance value; determining a contact angle of a critical point of contact between the corrugated sheath and the semi-conducting bedding layer based on the radius parameters and the thickness parameter; calculating volume resistivity of the semi-conducting bedding layer based on the radial resistance value and the contact angle; and comparing the volume resistivity with a preset evaluation parameter to obtain a defect detection result of the semi-conducting bedding layer.

Abstract: A tester for measuring insulating properties of cross-linked polyethylene, the tester including: a housing including a control panel; a high voltage chamber including an insulating cover, a fixed frame, an insulating oil cup, a high voltage electrode, a ground electrode, and a temperature control device; and a test circuit including a high voltage power supply, a voltmeter, a timer, an overcurrent protection device, and a digital thermometer. The high voltage chamber and the test circuit are arranged inside the housing. The control panel is arranged on the housing. The insulating cover is disposed on the high voltage chamber. The fixed frame is disposed inside the high voltage chamber. The insulating oil cup is mounted on the fixed frame. The high voltage electrode and the ground electrode are disposed oppositely inside the insulating oil cup. The temperature control device is disposed beneath the insulating oil cup.

Abstract: A device for measuring electrical treeing of medium voltage cables. The device includes a plurality of test units connected in parallel. Each test unit includes: a test cup and an insulating base. The test cup includes an inner cavity for accommodating a salt solution, an insulating cover equipped with a first electrode, and an opening. The insulating base includes a side wall, an insulating washer, a second electrode, a conductor, and a through hole from top to bottom. The test cup is disposed on the insulating base. The lower part of the test cup is surrounded by the side wall and presses on the upper surface of the insulating washer. The lower part of the test cup is in threaded connection with the side wall. The space between the opening and the test sample is sealed by the insulating washer.

Abstract: A device for measuring electrical treeing of medium voltage cables. The device includes a plurality of test units connected in parallel. Each test unit includes: a test cup and an insulating base. The test cup includes an inner cavity for accommodating a salt solution, an insulating cover equipped with a first electrode, and an opening. The insulating base includes a side wall, an insulating washer, a second electrode, a conductor, and a through hole from top to bottom. The test cup is disposed on the insulating base. The lower part of the test cup is surrounded by the side wall and presses on the upper surface of the insulating washer. The lower part of the test cup is in threaded connection with the side wall. The space between the opening and the test sample is sealed by the insulating washer.

Abstract: A tester for measuring insulating properties of cross-linked polyethylene, the tester including: a housing including a control panel; a high voltage chamber including an insulating cover, a fixed frame, an insulating oil cup, a high voltage electrode, a ground electrode, and a temperature control device; and a test circuit including a high voltage power supply, a voltmeter, a timer, an overcurrent protection device, and a digital thermometer. The high voltage chamber and the test circuit are arranged inside the housing. The control panel is arranged on the housing. The insulating cover is disposed on the high voltage chamber. The fixed frame is disposed inside the high voltage chamber. The insulating oil cup is mounted on the fixed frame. The high voltage electrode and the ground electrode are disposed oppositely inside the insulating oil cup. The temperature control device is disposed beneath the insulating oil cup.