Slip ring Loseless synchronous generator

Construction of a power plant with synchronous generator

Hyundai Ideal Electric C1110148

Horizontal Synchronous Brushless Generator

Complete Overhaul 5000 kVA, 11kV, 500 RPM, Brushless Synchronous Motor

The Stator in the temperature controlled drying oven

 Ovencure Of The Rotor Winding at GEF Works

 Servicing of Rotor Part

 Stator Winding After Overhaul Clean Varnish

 Stator Winding Before Overhaul Clean Varnish

Tan Delta Testing of the Stator Winding

Refurbishment Rotor Winding 2500kW, 48 Pole, 6 kV, Brushless Synchronous Motor

 Rotor Winding After Changing The New Thyristor Diodes

 Rotor Winding After Complete Service Re-varnish Painting

 Rotor Winding After Re-varnish

 Rotor Winding Before Changing The New Thyristor Diodes

 Rotor Winding Before Complete Service Re-varnish Painting

To Ensure The Rotor Sitting On Right Position

Overhaul Of Unit 1600 kW, 6.6kV, 750 RPM, Synchronous Motor

 Installation and Alignment Of Motor

 Oven Cure the stator with temperature control drying oven

 Ovencure The Rotor winding

 Reassemble of the rotor into stator winding

 Rotor winding After Service

 Rotor winding Before Service

 Synchronous Motor after service

 Synchronous Motor arrived at  GEF Works

 Synchronous Motor arrived at  GEF Works

 Synchronous Motor arrived at  GEF Works

 Synchronous Motor before service

 Synchronous Motor Service Process

 Synchronous Motor Service Process

 To Install the motor back to original position

 Unloading and Installation the motor at Site

Unloading and Installation the motor at Site

Marathon 900 kW Synchronous Generator

Brushless Synchronous Motor Rewind

 Brushless Synchronous Motor 2500kW 48Pole 6kV Before 

Rewind

Motor After Complete Rewind, Repair & Painting

 Motor Stator Winding After Complete Rewound Re-varnished

 Motor Stator Winding Before Complete Rewound

 Stator Winding   After Rewind

 

Stator Winding Before Rewind

Stator Winding Final Checking The New Coils Dimension Before Rewound

Stator Winding Rewinding Process

 Complete Rewind Brushless Synchronous Motor 500kW 48Pole 6kV

Source:www.gef.com.my

Transient Behavior of Synchronous Generators and Motors

The steady-state torque equation for a synchronous motor or generator is given by

 

where
• T = mechanical shaft torque
• P = number of poles
• ϕSR = air-gap flux (approximately proportional to the stator current)
• FR = rotor field MMF (proportional to the field current)
• δR = mechanical torque angle between rotor and stator field.

A plot of torque and rotor angle is shown . For a synchronous motor, the rotor field (FR) lags the rotating stator field (ϕSR) by the angle δR. For a generator, FR leads the stator field.
During a system disturbance or a fault, the power output of the generator is reduced. Because the power input to the prime mover does not change, the excess energy is added to the rotating inertia, which causes an increase in the angle between the internal voltage of the generator and the system voltage. After the fault is cleared, the generator power exceeds the power input to the prime mover as the angle is advanced. This condition brings the angle back to the initial value, and the rotor.

 

Torque vs. rotor angle relationship for synchronous machines in steady state

Synchronous motor rotor with amortisseur winding.G.E,Fort Wayne