Operating Philosophy

Proposed operating Philosophy of the Generator control system

Project : Rooty Hill RSL Club

Introduction

The site is currently with mains power supplied through three transformers each of 1000KVA. Each transformer is connected to a dedicated switchboard with a fault level of 43KA at 1 second.

All switchboards are not normally interconnected though they are connected to each other with a 1600A bus coupler which are locked by Integral Energy.

Each switchboard is also served by a diesel generator rated at 800KW, 1000KVA through 3 individual ATS. All the ATS will be upgraded to allow close transition and parallel with mains continuous operation with the new gas engine generator. The diesel generator will be a pure standby and only parallel with mains power during close transition return to mains after a power failure.

The new gas engine generator will be connected to the generator switchboard and should be able to parallel with the diesel generator to provide power to all switchboards through the existing three ATS.

Two operation modes are required and should be able to achieve the following operation requirement.

1, Cogeneration Operation mode
This mode is to run the new 1000KW gas generator to provide power to the club and parallel with the mains for constant full load operation or minimum import recommended by Integral Energy if the total load is less than 1000KW.

The objective of this operation mode is to achieve the best efficiency of the system including waste heat recovery to drive the absorption chiller.

This mode will be initiated by a PLC on a regular basis. The intention is to operate during the peak and shoulder tariff period.

If the generator is required in other time, manual initiation is still available.

2, Automatic mains failure mode
This mode is to use the current diesel and the gas engine generator set to provide the back up power for the Club during mains power failure. With both generators in operation, it is anticipated that load shedding is not required.

To avoid two generators in parallel with mains at the same time, a bus coupler will be installed in the generator common busbar so that the two generators will not operating in parallel during the close transition return to mains power.

Designation of circuit breakers are detailed below which will be controlled by the PLC system to achieve the above operation requirement.

GCB – Gas generator CB, motorized CB controlled by the Gas generator EasyGen parallel system to deliver power to the common busbar in the generator switchboard in cogeneration mode and parallel with the diesel in mains failure mode.

DCB – Diesel generator CB, motorized CB controlled by the Diesel Generator EasyGen parallel system to parallel with the gas generator during the mains failure mode.

GBC – Generator Busbar coupler, this is a motorized CB which will be opened during the close transition back to mains in the mains failure mode.

OCB1 – Output CB to deliver generator power to main switchboard 1, MSB1. This is a normal closed manual CB with general integral protection only.

OCB2 – Output CB to main switchboard 2, MSB 2, similar to OCB1

OCB3 – Output CB to main switchboard 3, MSB 3, similar to OCB1

MS1-GCB – Generator supply CB of ATS. This is the existing motorized CB on the generator supply side of the ATS in MSB 1 with electrical and mechanical interlock removed.

MS1-MCB – Mains supply CB of the ATS in MSB1. This is the existing motorized CB on the mains supply side with electrical and mechanical interlock removed.

MS2-GCB and MS3-GCB are the generator supply CB of the ATS in MSB2 and MSB3 respectively.

MS2-MCB and MS3-MCB are the mains supply CB of the ATS in MSB2 and MSB3 respectively.