ESS | Power System | 2012-05-05 | Frithiof Jensen

Contents

• Overview of distribution system• Substations and their limitations• Power quality and EMC • Grounding system

ESS | Power System | 2012-05-05 | Frithiof Jensen 3

Preliminary cable route, 24 kV cables

ESS | Power System | 2012-05-05 | Frithiof Jensen

Klystron Gallery

Cryoplants and Heat Pumps

Primary substation

Central Utility Building

Instruments

Target station

LINAC Tunnel

5

Target Station

Backup PowerPlant

20 kV Primary Station 20 kV Distribution Station

SEE LNDOM MRP

140/2063 MW

140/2063 MW

Inst. Hall 1

Inst. Hall 3

Inst. Hall 2

Cryo Test Stand

Cryo LINAC

Heat recovery

Cryo Target

Target Station

TunnelN

TunnelS

RF power

Aux. Power

6.6 kV Distribution Station

Block diagram

ESS | Power System | 2012-05-05 | Frithiof Jensen

600 V6000 KVA

Substations - LINAC

600 V6000 KVA

400 V4000 KVA

400 V4000 KVA

600 V6000 KVA

20 KV“A”

20 KV“B”

20 KV“B”

20 KV“A”

X X

IONSource

Front EndRACKS

The 400 V stations supply the LINAC controls.

This supply is “separated” from the Klystron Modulators due to potential EMC issues.

ESS assumes that the Ion Source canrun from a 400 V Station.

80 m

MEBT/LEBT/LWU/couplers

RFQDTL (5)

RF PWRRF PWR

RF PWRFront End

RACKS

ESS | Power System | 2012-05-05 | Frithiof Jensen

ESS | Power System | 2012-05-05 | Frithiof Jensen

CF/ACC

“Dumb” CB’s

ESS | Power System | 2012-05-05 | Frithiof Jensen 12

What to expect?

• Nominal voltage 400, (600), 690 or 6600 V– Maximum voltage variations +/- 10 %– Typical voltage variations +/- 5 %– Backup power + 10 % / -15 %– Random step changes of 1.5% (increase and decrease) of the supply voltage

may occur due to operation of the tap-changers of the main transformers. – Infrequent voltage dips shorter than 150 ms are permitted!

• Nominal frequency 50 Hz, +/- 1 %– Maximum variations 50 Hz, +4 % / −6 %– Backup power 50 Hz ± 15 %

• Total Harmonic Distortion, THD– Maximum value 8 %, 40’th overtone inclusive– Typical value 2 %– Voltage unbalance < 2 %

ESS | Power System | 2012-05-05 | Frithiof Jensen

ESS | Power System | 2012-05-05 | Frithiof Jensen

Implementation

EMC groundingmesh

Welded joint

Terminal pad

ESS | Power System | 2012-05-05 | Frithiof Jensen

questions

• Interfaces– Power quality, voltage stability needed (dips), sensitivity

to EMC/disturbances. – Is the grounding system adequate?– Power & Voltages required? Presently 400 V is

assumed, with a local LV distribution panel as the interface point.

– Where is(are) the interface(s)? ESS assumes that we have a connection point at a LV panel.

– UPS / Backup requirements? – Electrical CAD system and standardisation.