1General description

NEPTUNE family converters are two-quadrants power converters designed to provide up to 24 kA and 110 V in cycling mode to supply septa electromagnets for the LHC and North-Area injections. A NEPTUNE power converter consists of one to four power racks connected in parallel. Each power rack comprises two power bricks connected in parallel, each containing an isolated AC/DC converter.

 

Figure 1. NEPTUNE topology.

 

Family	NEPTUNE
Configuration	NEPTUNE 4P	NEPTUNE 16P
HCR code	HCRPNEA	HCRPNEC
Input Power	400V/630A/50Hz	4×400V/630A/50Hz
Load impedance	0-80μH/6-8mΩ	80-100μH/2-4mΩ
Dimensions [m]	W× D× H = 2.5 × 1.5 × 3.5	W× D× H = 6.4 × 1.5 × 3.5
Weight [kg]	5t	13t
Application	Injection for North-Area and for the LHC
Control Type	Reg FGC-3 type 10
Precision class	class 4 (100ppm)	class 3 (50ppm)
Voltage ripple [V]	TBD	TBD
Operating conditions	Altitude: <2000m above sea
	Operating temperature: 0..30°
	Humidity: 30-85% at 30°
	Overvoltage category (primary): III according to IEC-61800-5
	Overvoltage category (secondary): II according to IEC-61800-5
Cooling	24 L/min	96 L/min

Table 1. NEPTUNE converters ratings.

 

2NEPTUNE team

WP responsible: X. Bonnin

R&D, design: J. Savary

Hardware - Software: S. Reignier, E. Coulot - O. Michels

Production, Operation, Validation - E. Coulot

3Electrical schematics

NEPTUNE 4P is depicted in Figure 2. It consists of:

• One main rack with the control electronics, the water distribution, the output filter, and the DCCTs

• One power rack which includes two power bricks, each of which is made of:

  • A power transformer (coupling extended delta-wye 11.5 - Dy11.5)

  • A 6-pulse diode rectifier with its DC filter

  • Two IGBT switching legs with four HF chokes

NEPTUNE 16P consists in the same CERN control electronics and four power racks instead of one.

 

 

Figure 2. NEPTUNE 4P electrical schematic.