Time constants Armature

The above expression is adequate for data that are typically available for the industry. The armature resistance Ra is only present in the time constant Ta. (Krause offers a more complete solution in which the omission of Ra is minimised. The effect is then to modify the time constant Ta... 

Figure 20.4 Short-circuit current decrement for a 2500 kW and a 37 kW induction motor. These motors have a relatively high armature time constant Ta that causes the initial offset of the waveform. The deep bar effect in the rotor has been taken into account.

Several out-of-pUe mock-up expoiments have been conducted to demonstrate performances on holding force, response time, thermal endurance test under sodium, and measures against particle accumulation on the magnetic surface. The transient response tests with simulated ATWS conditions confirmed the time constant of the armature. In addition to the out-of-pUe tests, in-pUe mock-up and matmal expoiments were conducted in JOYO (Nakanishi et aL, 2010 Fujita et aL, 2011). The control rod holding stability imder the actual reactor-operational enviromnent was successfully confirmed. 

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