Avid Technology MV3000 DELTA User Manual

T1689 Technical Manual Rev 07 Introduction
MV3000 Air Cooled DELTA Drive Configurations
Page 17
1.4.1 DFE Network Bridge
A DFE network bridge comprises of one or more diode rectifier modules, plus ancillary components, which
could include:
• Line reactor;
• Fusing;
• Pre-charge circuit;
• Interbridge transformer;
• D.C. Link inductor.
The network bridge converts the a.c. supply to an unsmoothed d.c. voltage. Power flow is from the network
supply only.
Harmonic currents produced in the supply system by variable speed drives with uncontrolled rectifier inputs
may be reduced by changing from 6 pulse to 12 pulse (6 phase) input.
In the case of a 12 pulse input:
• A phase shifting transformer is used to produce the additional 3 phases which are phase shifted
by 30° as shown in Figure 1–1. These two sets of three phase supplies are rectified by two
rectifier bridges.
• Instantaneous voltage differences, between the outputs of the two rectifiers, are absorbed by an
interbridge transformer connected between the two positive outputs of the rectifiers. The
output to the d.c. link is taken from the centre-tap of the interbridge transformer.
1.4.2 Sinusoidal Front End (AEM Network Bridge)
The network bridge of an AEM drive comprises of one to six DELTA transistor modules. The network bridge is
combined with the following ancillary components to form a Sinusoidal Front End (SFE):
• Line reactor;
• Fusing;
• PWM filter;
• MVM unit;
• Sharing reactors;
• MV3000e Controller.
The SFE bridge can be used to convert the a.c. supply to a d.c. voltage, but also has the capability to allow
regeneration of energy back into the network, and as such is required for power generation applications (e.g.
wind turbines).
The AEM network bridge provides a very clean waveform, but the harmonic content will require filtering.
1.4.3 Machine Bridge
The machine bridge converts between a d.c. and an a.c. voltage of variable frequency and amplitude.
Generally in a DFE system, the power flows from the d.c. link, out into the a.c. load. In an AEM system, power
flow is bi-directional.
The machine bridge comprises of one to six DELTA transistor modules and the following ancillary components:
• Sharing reactors;
• Fusing;
• MV3000e Controller.

Avid Technology MV3000 DELTA Specifications

General

Brand	Avid Technology
Model	MV3000 DELTA
Category	Control Unit
Language	English