Generator rotor testing

TESTING GENERATOR ROTOR WINDINGS. Inspection of Large Synchronous Machines. Testing : Electrical Insulation for Rotating Machines.

The insulation resistance is typically in the thousand or tens of thousands of megohms. This test can be used on both generator rotors and stators, as well as motor armatures and stators.

Polarization index (DC MEGGER).

Dielectric absorption (polarization index).

These services can be provided at our rotor service facility in Columbus, Ohio or at your site. BRIEF TEST PROCEDURE FOR AC GENERATORS. Resistance measurement on main stator, exciter stator and exciter rotor . Insulation resistance test before and after HV test on main stator, main rotor , exciter stator and exciter rotor. High voltage test on main stator.

Mechanical stress in rotor windings cause inter turn faults (short circuits), which can lead to magnetic imbalance in generators and motors. This causes higher shaft vibrations, resulting in stress and damage to the bearings. Similar to sweep frequency response analysis (SFRA), the pole drop test is performed on single pole . Reflective Surge Oscillograph (RSO).

Electrical tests are performed at the generator main leads and visual inspections conducted if access is available). The test voltage on rotors is . Insulation integrity of the Stator and Rotor. Shorted turns can also cause unbalanced magnetic flux in the air gap that can also . Abstract— Detection of inter turn shorts in rotor windings of high voltage turbine generators (TG) has emerged as one of the important diagnostic measures in condition monitor (CM) for uninterrupted power generation. Conventional test methods cannot identify the location of defects. This increase shall be accomplished in not less than seconds nor more than seconds.

The maximum test voltage for rotor windings shall be equal to 0volts plus twice the highest rated voltage of the generator. Determines presence of contamination . Rotor shorted turns Major outage . However, there are other simple methods of testing low resistance windings, which are included in the various test procedures, i. This procedure enables the main generator , (stator), and windings to be tested while running the generator at normal spee without load.