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7 operating characteristics, 1 dual-quadrant operation, Introduction – American Magnetics 05100PS-430-601 Integrated Power Supply System User Manual

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10

Rev. 5

Introduction

Operating Characteristics

1.7 Operating Characteristics

The Model 430 Programmer has

been designed to perform with var-

ious power supplies to allow the

user the greatest degree of system

flexibility. The power supply and

Programmer combination are cate-

gorized by one of three forms: sin-

gle-quadrant, dual-quadrant, and

four-quadrant. For sake of clarity,

the term quadrant is defined as

one of four areas of a cartesian

coordinate system where the

abscissa is current and the ordi-

nate is voltage. Refer to Figure 1-4.

1.7.1

Dual-Quadrant Operation

In the Model 05100PS-430-601 dual-quadrant Power Supply system, an

energy absorber is added in series with the unipolar supply; this allows

stored magnetic energy to be converted to thermal energy, thereby

allowing much faster magnetic field reduction. This corresponds to

operation in quadrants 1 and 4 of Figure 1-4. The disadvantage to this

type of system is that energy is being dissipated in the energy absorbing

element whenever current is flowing. This loss is sometimes a significant

portion of the power required to operate the system.

20

-20

200

-200

V

I

Positive Current

Flow Direction

Positive Voltage

Polarity

Positive Current

Flow Direction

Negative Voltage

Polarity

Negative Current

Flow Direction

Positive Voltage

Polarity

Negative Current

Flow Direction

Negative Voltage

Polarity

1

2

4

3

Figure 1-4.

The Four Regions, or

Quadrants, of System Operation.

Magnet

Coil(s)

Persistent

Switch

(optional)

Misc. Line Losses

Model 420

Shunt

Energy

Absorber

V

Unipolar

Power Supply

Current

Figure 1-5.

Dual-Quadrant System with Resistive Shunt

430