Patent ID: 11936238
Assignee: DELTA ELECTRONICS, INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 6:
7. A magnetic flux compensation method of an uninterruptible power apparatus coupled between a power grid and a load, the uninterruptible power apparatus comprising a bypass path and a power conversion module, and the bypass path coupled to the power grid and the load; the bypass path comprising a switch unit, and the switch unit comprising a first thyristor and a second thyristor connected in anti-parallel; the bypass path receiving a first voltage provided by the power grid through a grid terminal, and transmitting the first voltage to a load terminal coupled to the load, the method comprising steps of:
(a) realizing that the first voltage is abnormal, and the time from realizing the abnormality of the first voltage to turning off both the first thyristor and the second thyristor is a forced commutation period,
(b) turning off the first thyristor and the second thyristor by injecting a second voltage into the load terminal based on the abnormality of the first voltage during the forced commutation period, so as to provide the second voltage as a reverse-biased voltage to the first thyristor or the second thyristor that are not turned off,
(c) during the forced commutation period, calculating a magnetic flux offset amount based on an error amount between the second voltage and a voltage command, and calculating a compensation amount based on the magnetic flux offset amount, and
(d) providing a compensation command corresponding to the compensation amount so as to control a DC/AC conversion circuit of the power conversion module based on the compensation command and the voltage command to provide a third voltage to the load terminal.