Introduction

In 2002, NR successfully developed the PCS-9500 HVDC control and protection system with its own intellectual property rights, which had been successfully applied to some significant projects. PCS-9500 control and protection system is a complete system solution of the control and protection for HVDC and FACTS of voltage level up to ±800kV. It includes the following features:

l       Powerful and flexible modules built with state-of-the-art computers, microcontrollers and digital signal processors.

l       High performance field-bus with industry standard and fiber optical communication links.

l       All critical parts of the system are designed with inherent parallel redundancy.

l       Graphic platform for programming and commissioning.

l       Open Industrial software INTOUCH for HMI.

l       Electronic measurement system transmitting data through optical fiber.

The PCS-9500 series includes PCS-967 AC filter protection and PCS-977 commutation transformer protection. The PCS-967 offers protection for AC filter in all kinds of connection type in HVDC transmission project with complete electric protections required by an AC filter.The PCS-977 is designed for application on commutation transformers of different connection types in a HVDC transmission project with voltage level higher than 220kV.

Structure

The PCS-9500 control and protection system comprises two levels in hierarchical structure: station level and bay level. The functions related to station level are SCADA system and station CAN network. The functions related to bay level, which are control and protection devices, are divided according to the physical location of the control and protection systems.

The PCS-9500 control and protection system is logically built up of several cells which serve a physical or logical part of the plant. Basically each control-location is considered as one cell. The cells control and protect one part of the plant with a minimum of signal exchange between the different cells. A fault in one of the cells will not affect the other parts of the plant. The overall functions and signal exchange common for all equipment in the plant and this is done at station level.

Features

l       High reliability is the most important goal

l       Overall redundancy of the system.

l       Independent of control and protection equipment for each 12 pulse converter unit.

l       Bipolar level function segregated to pole level equipment.

l       Overall duplicate protection system.

l       One AC control system handle one 3/2 bay.

l       Overall integrated SCADA system.

l       No power loss with pole level equipment fault.

l       The DC control systems are based on a hierarchical design to achieve the highest reliability.

l       The DC control function is divided into pole control level and bipolar control level.

l       All devices are duplicated.

World-Class HVDC Dynamic Test Model

NR has built up the first set of Combined HVAC and HVDC Dynamic Test Model in the world. Besides, NR possesses the HVDC Digital Dynamic Test Model and the HVDC Analog Dynamic Test Model. The unique Combined HVAC and HVDC Dynamic Test Model is one of the largest dynamic power system simulators worldwide, which can simulate all kinds of faults according to what customers would like to see. These Test Models are used for checking each panel to ensure that the ordered panels meet the specification in the project.