Wiring
27
Figure 4.11 Wiring of regenerative unit.
4.5.5 Wiring of Common DC bus
Common DC bus method is widely used in the paper industry and chemical fiber industry
which need multi-motor to coordinate. In these applications, some motors are in driving
status while some others are in regenerative braking (generating electricity) status. The
regenerated energy is automatically balanced through the common DC bus, which
means it can supply to motors in driving status. Therefore the power consumption of
whole system will be less compared with the traditional method (one inverter drives one
motor).
When two motors are running at the same time (i.e. winding application), one is in driving
status and the other is in regenerative status. In this case the DC buses of these two
inverters can be connected in parallel so that the regenerated energy can be supplied to
motors in driving status whenever it needs. Its detailed wiring is shown in the following
figure:
