WXH-803A_Xuji microcomputer line protection device

1 Overview

1.1 Scope of Application

The WXH-803A series protection device is mainly used for longitudinal differential main protection and backup protection of transmission lines with voltage levels of 220kV and above.

1.2 Protection configuration

The WXH-803A/D2/R1 line protection device includes a full line quick action main protection with fiber optic current differential protection as the main body, and a backup protection consisting of three-stage phase to phase and ground distance protection, phased zero sequence protection, and inverse time zero sequence protection; Configure phase based reclosing and automatic reclosing for conventional lines, as well as three-phase inconsistency protection.

1.3 Product Features

Based on the high-performance and highly redundant Xuji next-generation hardware platform, visual logic development tools are used to achieve transparent protection design. The principle of variable action characteristics comprehensively improves protection performance. Advanced fiber channel technology, the "log system" of device memory, and the "black box" fault location technology are the main features of this protection device.

1.3.1 Protection Performance

Fast action speed, with a fault action time of less than 10ms at the near end of the line, and a typical metallic fault within the main protection line of less than 20ms;

Differential protection and distance protection adopt the principle of variable action characteristics, greatly improving protection sensitivity while ensuring protection speed;

Adopting dual digital filtering algorithm to coordinate work, effectively ensuring fast action and measurement accuracy of distance protection;

The adaptive oscillation criterion and advanced oscillation recognition function ensure that the distance protection can reliably lock in case of system oscillation and faults outside the oscillation zone, and quickly act when the system is not oscillating, and reliably act on faults inside the oscillation zone;

1.3.2 Software and Hardware Platforms

Adopting the high-performance, reliable, and powerful Xuji next-generation hardware platform, 16 bit high-precision dual AD, floating-point operation 32-bit DSP, fully considering redundancy and functional expansion, multiple DSPs work together to complete the main and backup protection functions;

The visualized logic development tool VLD, in which all protection logic is composed of different visualized flexible relays, achieves complete transparency design of microcomputer protection;

The software runtime memory content is recorded in the "log system" and the protection logic information is recorded in the "black box" to quickly and accurately locate abnormal situations;

The device adopts a whole panel and a standard 6U chassis, with plug-in connections and strict separation of strong and weak electrical circuits, greatly improving the anti-interference ability of the device;

The AD circuit, CPU plugin, relay coil, and other components of the device are fully self checked.

1.3.3 Fiber Channel Technology

Fully supports frame based communication format, enabling precise diagnosis and localization of channel faults;

Channel monitoring follows the requirements of G.826 standard, and detailed channel information enables users to intuitively understand channel quality and accurately locate faults;

Capable of outputting instantaneous data from both ends, facilitating channel testing, detection, and maintenance;

Channel transmission sampling value repair function, using interpolation algorithm to repair bad sampling points caused by occasional frame loss or errors in the channel, improving the ability to protect against channel errors;

Fiber channel adaptive master-slave positioning technology, no user tuning required;

Adaptive CT transformation ratio, which means there is no need to set the contralateral transformation ratio;

Dedicated fiber channel: 2 Mb/s high-speed data transmission;

Reuse transmission channel: Reuse 2Mb/s data rate (E1) interface for transmission.

1.3.4 Operating Interface

Utilizing the XJ GUI interface design tool, achieve flexible customization and user-friendly design of the operating interface;

Display of main wiring diagram and rich real-time data;

Class 2 WINDOWS menu, through menu prompts, all device operations can be completed.