SY-EPC-LPC Polarity-Switch A1 Design

Introduction

Planning

TBD

Development Planning

Power Converter Needs, deliveries, prices and schedules .xlsx

2012		2013	2014

Physics		L.S.1	Physics
Specification	Tender	Production	Recep.	Instal.	Commiss.

HIE-Isolde Projective Planning

2013						2014
01-02	03-04	05-06	07-08	09-10	11-12	01-02	03-04	05-06	07-08	09-10	11-12
Pre-Design	Design		Design (Cont.)						Hie-Isolde Installation, Commissionning		Hie-Isolde Operation
Pre-Design	Design		Compass Inst.	Compass Operation
			Prototype Design (2x)				Pre-Series (2x)		Series(x)

Projective Planning

Design Notes

Commercial devices were considered once, then forgotten, leading to an internal design. Reasons are:
- A Modular Design is the goal so that this unit can be adapted easily to lower or higher current.
- Integration with FGC3 will be optimized.
- Internal Design Polarity Inverter will be possible to use with in any kind of converters, since mainly driven by FGC3 and not by the power supply.
Interfaces Design:
- Control signals were extracted from FGC3 specification and should allow FGC3 to directly control unit.
- A signal was added, providing the MOVABLE status to FGC3 so that it is possible to know if all conditions are ok to move the switch, before trying it endless if not possible.
- 2 identical and additionnal interfaces are foreseen, in order to cope with the case of 5A leading to too high energy stored in load, to be compatible with several possible cases:
  - Very Low Stored Energy magnets:
    → No need to use any SKPOLINTLKx interfaces since the polarity switch internal current treshold of 4..5A is sufficient to allow the contactors to change state. (still possible to add extra safety if required, see below)
  - DCCT-based Converter powering a magnet storing > Ej.critical @ 5A + no REE installed:
    → Use directly the contact to POLSW_INTLK1 provided by the DCCT giving 0A status, which is precise enough in general to ensure energy stored in the magnet is safe since measured to be close to 0A. It is also possible to add the Power Supply status + adequate timer.
  - LEM-based Converter powering a magnet storing > Ej.critical @ 5A + no REE installed:
    → Since LEM precision is generally too low around 0A, use the Power On/Off signal from the Power Supply to POLSW_INTLK1, and trim the according timer to ensure that discharge time once magnet is not powered anymore is within the selected timing to ensure energy stored in the magnet is sufficiently low.
  - Magnets storing > Ej.critical @ 5A with REE (external extraction system) installed:
    → Several combinations are possible. It is possible to use REE status + adequate timer to ensure current in magnet is suffficiently low. It is still possible to use DCCT signal if available, as it is also possible to use Power Supply on/off status. The first movable required condition will allow the switch to be controlled.
  - Converter uses 2 Power Supplies in //
    → The 2 interfaces could be used in the way Polarity Switch > Power Supplies to ensure both will stop if Polarity Switch is in fault. Also, Power Supply on/off status can both be used. Combination with DCCT, or REE signals are also possible.