North Texas Municipal Water District (NTMWD) supplies municipal water authorities all over Texas, using large lakes as water resources.
One of the largest is Lake Texoma.
NTMWD's Lake Texoma station began with two 4,000 HP 4160V pumps. Looking forward to prudently meet increasing water demand, NTMWD contracted for the addition of two 6,100 HP 4160V pumps at the same station. They were specified, quoted, and installed with softstarters.
They couldn't start. For years. Turned out that the power system just couldn't supply enough power to start the motors.
The answer was 2-stage, 12.2 MVAr Dynamic VAR source - an SVC, supplied by North East Power Systems (NEPSI), who integrated T-Star's technology into an entire system. Shipped on a truck, installed on a pad, it is an entire retrofit "system in a box".
Here's what it looks like outside. The system is on the right, the pump station is left rear
Big Motors on the inside. Pumps below the floor.
The customer specialies in water. T-Star provides ongoing remote analysis and support for maintenance personnel.
As starting the pumps is critical to the water district performance, the customer requested analyses of motors starting. The following charts are partial excerpts of the customer report. All data shown is normally recorded and is accessible locally by the customer and remotely by T-Star personnel.
Plot of a 4,000 HP motor starting across-the-line, showing voltage swings and dynamic compensation.
Currents though the SVC and the motor bus during the starts:
Response to the motor over the first 3 cycles:
6100 HP motor start with Softstarter
And to demonstrate the speed of data collection, the actual current waveforms as the 6,100 HP motor starts. Can you tell a starter is involved?