Power Converter Characteristics Design & Operation Responsibles Power Converter Architecture Power Part Control Part

Magnet Protection Power Converter Components Magnet Types Machine Installation Production Contract & Contact History

Power Converter Characteristics

Design & Operation Responsibles

Responsibles
	Serge PITTET Technical referee, designer
	Christophe MACHADO Responsible 1
	Ludovic CHARNAY Responsible 2

Power Converter Architecture

Power Part simplified Architecture / Topology .vsd

Simplified Operation Overview

• Simplified Operationnal chronograms
  • pre-warning starts charging the capacitor bank.
  • warning indicates that the discharge will soon start.
  • Start discharging the capacitor bank into the magnet.
  • Meas indicates when the current value must be sampled.
  • Stop the capacitor discharge. Note that this is a new proposed signal and that it should be optional (the converter will limit the pulse to an internal maximum).

Power Part

Voltage Source is based on a full bridge phase shifted topology followed by a linear stage in series with a fulle bridge to allow the 4 quadrant operation.

One precision resistor is used for the high precision current loop (FGC), and is located directly in the converter.

Converter is compatible with 19'' standard dimensions.

Power Part simplified Architecture / Topology .vsd

Typical Curves

Control Part

Magnet Protection

Power Converter is part of magnet protection scheme, even if not directly fully responsible of the monitoring and diagnostic of the magnet status. WIC (Warm Interlock Controller) can interlock Power Converter if magnet safety requires it.

Power Converter is then expected to:

• Always ensure that external protection system can stop the Power Converter through a safe signal called Fast Abort.
• Stop powering the load in safe way (handling the magnet energy even when stopping, through dedicated system called crowbar). This active system provides a safe resistive discharge path for magnet current (energy).
• Monitor Earth current of the total circuit: converter + load (magnet and its DC cables), and take the right action if threshold reached.

• Earth System

  Detection system is an active / passive system, since relying on a converter state-controlled 100mA current source powering a 100Ohms resistor connected between earth and negative polarity of the Power Converter. A common mode voltage is then created, (100mA x 100Ohms = 10V) making possible to detect an earth fault even with converter being OFF (not condamned). Active system is disabled when Power Converter is set STANDBY or ON, with a 10 Ohms resistance series a fuse only being connected between negative polarity and earth.

  

  Earthing System simplified schematic .vsd

Power Converter Components

A power converter is actually a sum of different equipments under several different sections in the SY-EPC group. The modularity is a key factor for easier maintenance with regards to MTTR reduction.

• Power Module
  • Digital Controller: FGC3 + FGC3-dongle
  • FGC3 Fan unit

Magnet Types

Machine Installation

Production Contract & Contact History

Developped	CERN SY-EPC-LPC
	2012-2013
	Serge PITTET
	Ludovic CHARNAY
Manufactured	Denmark
	2012-2013
	CB-svendsen
Production	60 Pc

Converter Circuit Names