The new multidrives, extension of ABB Low Voltage Industrial Drives, based on a modular configuration of dramatically smaller inverter modules, were introduced on exhibit at the Hannover Messe 2004. Following the debut of the multidrives there, it has been a successful roll out to a wide range of applications and industries around the world. The modular configuration of the multidrive provides control of multiple motors across a 1.5 - 5,600 kW power range, from 380 V up to 690 V. A single rectifier unit can be combined with a host of inverter units that are connected in parallel, to provide output current required by any given application. The multidrive offers a state of art solution for offshore and drilling applications - ultra compact and modular design ensures high availability and service.ABB's multidrive is built from industrial drive modules that are connected to a common DC bus bar. The common bus bar is used to supply the drive modules with DC power, and each module then inverts the DC to AC and powers an individual motor. The DC power is derived from a single supply unit (rectifier) that is built into the front of the same multidrive configuration. The standard DC bus arrangement enables single power entry and common braking resources for several drives. "Common braking includes regenerative braking and motor-to-motor braking depending on the demands and modes of the various motor loads in a process or on an original equipment machine," according to Tuomo Tarula, market manager for Marine and Offshore, ABB Drives, Helsinki.
Modular construction simplifies the total installation and results in many benefits: savings in cabling, installation and maintenance costs; reduced line currents and simpler braking arrangements; energy distribution over the common DC bus bar, which can be used for motor-to-motor braking without the need for a braking chopper or a regenerative supply unit; reduced component counts; increased reliability; and space savings.
