| 摘要 |
<p>An uninterruptible power supply (UPS) device 10 is described having only half the number of inductors and storage capacitors of a conventional UPS. The UPS 10 has an input stage 12 connected to an AC power supply and an output stage 14 for supplying AC power to an appliance. The input stage 12 has a first switching means 16 connected in series with the output stage 14 and a second switching means 18 connected in parallel with the output stage 14. The output stage 14 has a third switching means 20 connected in series with the input stage 12 and a fourth switching means 22 connected in parallel with the input stage 12. Each of the switching means 16, 18, 20 and 22 is capable of switching current in two directions depending on control signals supplied to the switching means by a controller 24. The controller 24 controls the direction of current through each of the respective switching means in response to detected changes in power conditions. Each of the switching means 16, 18, 20 and 22 are controlled by controller 24 to be in either an ON condition, an OFF condition or a switching condition in which the switching means is switched at high frequency. Replacement of the four bulky items in a conventional UPS with a single inductor and a small high frequency storage capacitor results in a significant reduction in physical size. The remainder of the components in the UPS are mainly semi-conductors which therefore lends itself to high integration.</p> |
