Marine Electrical Systems

• NISHISHIBA's electric propulsion systems make a contribution to safety operation with redundancy, better operation with lowest vibration and sound noise and minimized machinery space.
• Nishishiba proposes best solution against the harmonics produced by inverters.
• The inverter for propulsion motor can be used for other applications (bow thruster, cargo pump, loading compressor motor, etc)
• By multiple inverters integrated control system, the both applications can be operated at the same time. (Patented)

• NISHISHIBA's shaft driven generating systems make a contribution to saving of maintenance work as well as saving energy.
• Various driving arrangement such as intermediate shaft mounting, overhang on main engine, and step-up gear connection.
• Direct connection to 6.6kV main bus without step-up transformer.
• The control system has adopted digital control to get high reliability and control performances and to realize easy operation and maintenance.
• Additional functionality of motor only as generators can be applied to a variety of purposes.
  Assisting of the main engine by booster mode at the peak, the rated output of the main engine can be reduced.
  The propulsion mode can be used for slow-speed operation without main engine or emergency operation at main engine failure.

• Inverter driven system controls speed of the motor to drive auxiliary machinery in ships at optimum speed and contributes energy-saving operation.
• Proven various applications such as cooling seawater pump, cargo pump, and L/D compressor for LNG ship.
• Proposal of energy saving with best speed control of cooling seawater pumps.
• By applying a sensor-less vector control system, motor can be controlled smoothly even at low-speed area with the high torque.
• By applying the vector control system with a sensor, application for crane control is possible.

• High reliability and easy operation by inverter driven with vector control.
• Various merits:
  • No risk of causing environmental pollution from oil leaks.
  • Easy outfitting due to no hydraulic piping.
  • Maintenance free without oil change and piping maintenance.
• Improvement of mooring efficiency by triple speed operation on low loads.

• The electric balancer reduces the ship's hull vibration by generating the vibration of same frequency and negative phase to the ship’s hull vibration which is the secondary harmonics to the revolution of the main engine.
• Wide range of vibratory force, 11 to 154 kN.
• The electric balancer can be easily applied to the existing vessel.

• Brushless A.C. generators meet various needs of marine field and output voltage from low voltage (A.C. 450V) to medium voltage (A.C. 11kV).
• Both diesel engine and turbine driven generator are applicable.
• From low voltage (A.C. 450V) to medium voltage (11kV) is applicable.
• Standard enclosure is either drip proof (IP22) or totally enclosed with water cooled air cooler (IP44).
• Highly reliable F class insulation system is applied.

• Induction motors are used to drive all kinds of machineries in ships such as bow-thrusters , F.D. fans and oil pumps for deck-machineries. Standard induction motors in compliance with JEM standard (and IEC standard) are also applicable.
• From low voltage (A.C.450V) to medium voltage (11kV) is applicable.

Fans and blowers such as internal motor type axial flow fans, axial flow fans with bent-duct, turbo fans and sirocco fans used for ventilator of each division, forced draft fans, pump room fans and auxiliary blowers for the main engine are available. For ventilation of cargo hold of the vessel such as RO/RO, explosion-proof internal motor type axial flow fans are available from our standard products.