Motor behavior is suspect when performing motor starting study
I'm performing a motor starting study and used IMD to create my CIM5BL dynamic model for 3600 HP motor.
1327 'CIM5BL' L9 2
0.02180 0.1200 2.8900 0.04800 0.0075
0.00800 0.0180 1.0000 0.10000 1.2500
0.4000 3.1400 0.0000 0.63249 0.0000
0.0000 0.0000 0.0300 0.86127 /
Based on some other forums, I've changed my time step and frequency step as noted below. The other forums recommend time step of 0.001 seconds but after experience non-convergence and "NAN" errors, the time step was further modified.
psspy.dynamicssolutionparam2([i,i,i,i,i,i,i,i],[0.5,f, 0.00075,0.004,f,f,f,f])
The motor's response time and the speed deviation don't perform as expected. Initially there's a 0.5 second flat start before turning the motor load on, as discussed in the Program Application Guide 2. The torque spikes at 0.7 seconds and reaches nominal torque around 2 seconds. The current spikes to a value not quite LRC and is already approaching unity by 1 second. The speed deviation oscillates slightly rather than a smooth curve approaching 0.
I'm at a loss at to what to do. The motor curves in IMD match the motor documents, but not seeing those same curves when running dynamic analysis in PSS/e.
