ABB ACS 6000 medium voltage drive

ABB ACS 6000 medium voltage drive

Efficiency and reliability

The ACS 6000 uses the IGCT (Integrated Gate Commutated  Thyristor) power semiconductor, which is an ideal switch  for high-powered medium voltage applications. The use of  IGCTs results in low parts count, providing an efficient and  reliable drive.

Due to low losses, the IGCT requires less cooling capacity  and smaller cooling equipment. The IGCTs fast switching  enables the implementation of unique control algorithms.

The IGCT converter design allows the use of a fuseless main  circuitry. This increases the availability of the drive since the  protective functions are actively controlled by the converter,  and the recovery from a fault can be accelerated.

Key features and benefits

– High power and outstanding reliability increases the safety  of the ship and decreases maintenance costs 

– Smooth torque over the entire speed range reduces noise  and vibration levels 

– Compact and lightweight design provide basis for cost- effective construction 

– Redundant main propulsion drives provide adequate  power for the ship to operate safely if a malfunction occurs 

– Minimized energy and fuel consumption  

– High immunity to varying climatic conditions and vibra- tions increases availability

Modular design requires minimal engineering

The ACS 6000 is available with five sizes of inverter modules  (3, 5, 7, 9 and 11 MVA). The optimum configuration for specific  applications is achieved by combining the modules with minimum engineering effort.

Compact and robust marine design

During the design and development phase special care was  taken to meet marine and offshore requirements resulting in a  small footprint, flexibility and lightweight design. The ACS 6000  meets the requirements of marine certifications, such as Lloyd’s,  DNV and ABS.

High performance with Direct Torque Control (DTC)

The ACS 6000 uses ABB‘s motor control platform, Direct  Torque Control (DTC) which provides the most accurate torque  and speed control ever achieved in medium voltage drives.  As a result, control of the drive is immediate and smooth  under all conditions.

With DTC, full torque at zero speed can be achieved without  the use of speed encoders, thereby reducing maintenance  costs and ensuring high availability. DTC also ensures minimum torque ripple and results in reduced machine wear.  The high switching frequency generates lower noise levels.

Propulsion and thruster for shuttle and service vessels:  redundant concept

In a redundant main propulsion configuration, the power system can be split. Operation at reduced power is, therefore,  maintained in case of partial failure of the converter.

The main propeller (Azimuth or conventional installation with  shaft) is driven by a variable speed drive tandem motor, which  is fed by a redundant ACS 6000 converter. For positioning  and manoeuvring, 2x2 thrusters on a common DC bus (Azimuth and propeller units) are provided. Due to the common  DC bus concept the number of transformers, MCBs and cabling can be reduced, resulting in smaller drive system size.