Petrochemical
In petrochemical industry, the one of main energy consuming equipment is the pump. The traditional drive solution can only run at the grid with fixed speed through the valve throttling to hydraulic coupling for speed regulation. The energy-saving result of site was not significant because of using hydraulic coupling to speed regulation.
Hence, the customer would like to achieve higher energy-saving efficiency through the revolution.
Nancal provides two model NC HVVF 6/6-1250 MVFDs. Depend on requirements of customers, VFD is connected with DCS remote control and added the auto-bypass cabinet, which serves as a backup to drag loading in case of failure or maintenance through using grid starting and running method. Thus, we can ensure the continuity of production.
For pump project, NANCAL VFD has function of power cell bypass with "Neutral Point Shift Technology", which can extremely satisfy the requirements of continuity operation of VFD.
Power cell bypass with "Neutral Point Shift Technology": When the power cell in VFD is damaged, it can automatically bypassed and VFD can keep running at all times.
Compared to normal power cell bypass, Neutral Point Shift Technology can increase the output voltage after bypassed. Under some configurations, VFD can totally ensure the rated voltage of motor in case of a power cell damage.
The project has been constantly operated since its acceptance in June, 2017. It helps customers energy-saving and improve the processes.
Attached is a comparison of MVFD and Hydraulic coupling in terms of energy-saving:
Flow change rate% | Shaft power rate % | Hydraulic coupling | VFD | ||
Motor input power rate% | Loss rate% | Motor input power rate% | Loss rate% | ||
100 | 100 | 108 | 8.0 | 108 | 8.0 |
90 | 72.9 | 86 | 13.1 | 79 | 6.1 |
80 | 51.2 | 68 | 16.8 | 55 | 3.8 |
70 | 34.4 | 52 | 17.7 | 38 | 3.7 |
60 | 21.6 | 39 | 17.4 | 25 | 3.4 |
50 | 12.5 | 29 | 16.5 | 15 | 2.5 |