1

HVDC P3 Project

CIAG Update 2 December 2011

Project Progress –Update

2

•HAY Converter Transformer Assembly

•HAY Thyristor Valve Assembly

•HAY & BEN Smoothing Reactor Installation

•BEN Converter Transformer delivery to site

Andrew Gard

HVDC Switchyard Reconfiguration HAY & BENExisting Configuration

1. P2 HVDC Bus

2. P2 DC Filter

3. P2 Neutral Bus

4. P1 HVDC Bus

5. P1 DC Filter

6. P1 Neutral bus

7. Common Neutral and E/L

Bus

1

2

3

4

56

7

HVDC Switchyard Reconfiguration HAY & BEN

Bipole Outage 29 Nov-5 Dec

Installation of Temporary bypass

cables

Relocation of Electrode line bus

Temporary relocation of capacitor

P1.C1

HVDC Switchyard Reconfiguration HAY & BEN

High level Breakdown of Stages

Bypass cable installations

Relocation of Electrode line bus (4)

Install DC Filter Resistors

Relocate P2 HVDC Bus (1B,8)

Install P3 HVDC Bus (4,3,1A)

Install High Speed Electrode Line Switch

(6)

Install Surge Arrester (6)

Install Station Ground Switch (7)

Install P3 High Speed Switch (2)

Install P2 High Speed Switch (5A,5B)

Final DC yard commissioning

Multiple short duration/weekend

outages Feb –May 2012

Pole 3 CommissioningHVDC Transfer requirements

2012

6

Example

Years

7

-400

-200

0

200

400

600

800

1000

HV

DC

No

rth

Tra

ns

fer

(MW

)

Time - Sept. To Dec.

2002 2005 2008

• Every year is different.

• An “average” year is unlikely.

• We won‟t know what transfers are likely until closer to the time.

Test Schedule

8

-1200

-900

-600

-300

0

300

600

900

1200

No

rth

Tra

nsfe

r (M

W)

Time - Sept. To Dec.

- 126 Tests

- 42 Days (6 Sept-24 Oct)

-Red Bars Are Monopole

- Yellow Bars Are Round Power/Bipole- Tests In Approximate Order Only

- Some Can Be Completed Simultaneously

Average Transfer

Analysis

9

-100

0

100

200

300

400

500

600

700

No

rth

Tra

nsfe

r (M

W)

Time - Sept. To Dec.

-Gray is what an average year would look like.

-Blue is a rolling average showing the trend.

-Green is the average transfer for all data.

-Yellow is the average daily peak and trough.

-The averages comes from the years 2002 to 2010

Test Schedule With Average Transfers• No naturally occurring South

transfer.

• For the series of low north

tests, the HVDC would be

constrained back.

• The medium north flow tests

are likely to fall within

scheduled transfer.

• The high and overload tests

will require a much larger

transfer than scheduled.

• The total net transfer will be

in the vicinity of 70 GWh

North.

• High level of reserve

required for the monopole

high power transfer tests

10

-1200

-900

-600

-300

0

300

600

900

1200

No

rth

Tra

nsfe

r (M

W)

Time - Sept. To Dec.

•The red lines are the highest and lowest transfers

between 2002 and 2010.

•The yellow lines are the average daily peak and

trough.

•The green line is the average transfer for all data.

Assumptions

• Assuming each test takes four hours. In reality the test time will vary.

The overload tests will be as short as half an hour.

• Assumes at least three tests are done per day. Some tests will be

done simultaneously which will save time, however some tests may

need to be repeated.

• The GWh estimate is based on these two assumptions.

11

Test Program Summary

12

Monopole

Round Power

Bipole

Total

Tests

Number

of Days

North Transfer

17 4 21 7

HVDC will need to be constrained back for this series of tests. The majority of tests are at

100MW but will need to operate as low as 35MW for others. The 21 tests are likely to be

run over seven days, taking up to 84 hours. The total transfer will be approximately 6GWh.

South Transfer

5 5 10 4

For this section of tests the HVDC needs to operate in south transfer. Again the tests range

from 35MW to 100MW. The ten tests will likely take three to four days taking up to 40

hours. The total south transfer be approximately 3GWh.

Monopole

Round Power

Bipole

Total

Tests

Number

of Days

North Transfer

10 24 34 11

If next year is an average year, then this sequence of tests are all likely to fall within normal

scheduled transfer. The tests to be conducted will be a number of power levels up to

350MW. The 34 tests will likely be completed over 11 days, taking up to 136 hours and

transferring approximately 43GWh.

South Transfer

2 12 14 5

The HVDC will again need to operate in south transfer. The tests are of the same power

levels as the medium north transfer. It will take approximately 56 hours over five days

transferring 17GWh.

26GWh

Number of TestsImplications

Net

Transfer

North

3GWh

Low Load - 0 to 100MW

Net

Transfer

North

Medium Load - 101 to350MW

ImplicationsNumber of Tests

13

Monopole

Round Power

Bipole

Total

Tests

Number

of Days

North Transfer

8 13 21 7

This section of tests is almost entirely 700MW. If next year is average we expect the daily

peak transfer to be between 400MW and 500MW. So for this section the HVDC will need

to operate in north transfer up to 300MW higher than usually scheduled. The 21 tests are

expected take close to 84 hours over seven days. Transferring about 71GWh north.

South Transfer

5 6 11 4

HVDC will need to operate in south transfer up to 700MW. The 11 tests are likely to take

around 44 hours spread over four days. The south transfer will be close to 30GWh.

Monopole

Round Power

Bipole

Total

Tests

Number

of Days

North Transfer

0 11 11 4

HVDC will need to be transferring power levels up to 1000MW. This is around 600MW

higher than what would be expected to be scheduled. The duration of these tests will not

exceed 30 minutes. The 11 tests will likely be conducted in the space of four days taking six

hours. The total transfer will be roughly 5GWh.

South Transfer

0 4 4 2

Again these four tests require the HVDC to operate in a south transfer at power levels up to

1000MW. All four tests should be able to be completed in a total of two hours over one or

two days. The south transfer for this series of tests is going to be in the vicinity of 2GWh.

Net

Transfer

North

41GWh

Net

Transfer

North

3GWh

Overload >700MW (Half an hour)

High Load - 351 to 700MW

Implications

Implications

Number of Tests

Number of Tests

Test Program Summary

14

•Further analysis against high and low storage

scenarios

•Develop detailed test schedule and confirm

commissioning roundpower options with Siemens

•Assess P3 secondary risk performance with the

System Operator

Test Program Summary

15

Commissioning requires an „industry‟ solution.– HVDC Transfer

– Reserve availability

Utilise the market – Minimum impact/disruption on day to day market operation

– Utilise commercial behaviour

Issues to be considered– Contracting for availability -adding certainty to completion of test programme

– Impact of unfavourable system conditions

Timeline 2012Dec-Jan Confirm test plan, HVDC transfer and reserve requirements

Feb-Apr Industry briefings on commissioning, HVDC transfer and reserve requirements

May-Jun Tender for availability where appropriate

Jul Contracts in place. Market based exercise

Aug Ready for P3 commissioning

HVDC Transfer and Reserve Requirements