Soft starting method and system thereof in the way of wave-skipping with stepped frequency and stepless voltage regulating for a motor
US8179082B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2007 |
| Grant date | May 15, 2012 |
| Priority date | — |
| Expiry date | Oct 30, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P27/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a soft starting method and system thereof in the way of wave-skipping with stepped frequency and stepless voltage regulating for a motor which can be applied to the large torque starting of AC motor under the condition of a power supply of a industrial frequency supply source and the safe starting of higher load. Trigger signals generated by a control system, in the soft starting method of the invention, act on five sets of anti-parallel thyristor valves connected between the power supply and the motor to conduct a pair of thyristors thereof according to a set frequency and sequence, and the motor is started from a standstill status to full speed in the way of wave-skipping by controlling the sets of the thyristor valves. The method may improve the starting torque for more than 10 times of the traditional motor soft starting of the voltage reduction and control the starting current for about two times of the rated current. The cost thereof is only 20-25% of similar frequency converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.