25 kV Overhead Line Equipment Switches

Introduction

Background

The Public Transport Authority of Western Australia (PTA) is responsible for the operation of all bus, train and ferry services in the greater metropolitan area under the Transperth brand. It also operates public transport services in regional centres, operates road coach and rail passenger services to regional areas under the Transwa brand and administers and manages School Bus Services (SBS).

The Network & Infrastructure (N&I), Electrical Engineering Branch are responsible for the maintenance and operational performance of 25 kV Overhead Line Equipment (OLE) and Traction power assets.

OLE Isolators provide a point of isolation in the traction circuit for the purpose of isolating sections or subsections of OLE for planned or unplanned maintenance. Generally the switches take the form of a horizontal or vertical throw knife switch, which when open provide a visible air gap between the supply and the OLE equivalent to at least basic insulation of 370mm. In their simplest form they are not capable of making or breaking current and are only operated once the power supply has been disconnected at the circuit breaker. In order to improve the flexibility of isolations, the PTA would like to trial the 25 kV load break switches that are capable of making and breaking capacities of rated normal currents under load applications.

Currently, all the isolators in the network are non-load break isolators and are horizontally operated mechanisms. By introducing these load break switches in the network, it will provide flexibility in operating the switches under live load conditions. The switches will also provide many advantages in various locations like junctions, places where access is limited or restricted, depot areas, yards, sectioning positions and in emergencies. This will benefit both projects and maintenance asset replacements across the PTA.

The objective of this tender is to procure 25 kV OLE switches in non-load break and load break configurations and to develop the system design for the successful product and obtain type approval.

This tender has an immediate impact on a number of upcoming PTA projects where OLE switches are required. The PTA also plan to renew a number of critical switches that are currently in operation on the network with these newly approved switches.

Scope of Requirement

This tender is for the supply of 25 kV OLE disconnectors, earthing switches and load break switches in rail electrification.

For further information regarding the scope and specification of this tender and the switches please refer to PTA200081 Supply of Goods (Book4) RFT Scope & Specification.