초록 ▼

The apparatus and methods of the invention provide conversion of a wide range of utility voltages found worldwide, to a fixed nominal voltage level. The invention therefore provides the ability to "plug in" to virtually any power source, and produce a desired nominal voltage for operation of electri

The apparatus and methods of the invention provide conversion of a wide range of utility voltages found worldwide, to a fixed nominal voltage level. The invention therefore provides the ability to "plug in" to virtually any power source, and produce a desired nominal voltage for operation of electrical equipment either alone or in conjunction with a UPS device. The voltage selection apparatus provides standard nominal levels of electrical power to equipment while utilizing power sources of varying voltage and frequency. The device is dynamically adaptive to the input power source, and maintains its output within a nominal range even where the input source varies to a substantial degree. The voltage selection apparatus comprises an input for receiving input AC voltage from a power source, and a transformer to produce an output voltage which is coupled to the input. The transformer has at least one winding and a predetermined plurality of winding taps used to achieve a desired nominal output voltage from the transformer. A voltage detector is coupled between the input and the transformer to selectively measure the input voltage and enable output of a selected nominal output voltage. A control circuit monitors the input voltage to produce control signals in response thereto, and relay devices are controlled to select a predetermined winding tap based upon the input voltage to produce an output from the transformer within a desired nominal voltage range.

대표청구항 ▼

[ What is claimed is:] [1.] A method of gradually supplying an electrical load with an AC input voltage to reduce current inrush, comprising the steps of:a. detecting a zero crossing of said AC input voltage;b. preventing application of said AC input voltage to said electrical load for a predetermin

[ What is claimed is:] [1.] A method of gradually supplying an electrical load with an AC input voltage to reduce current inrush, comprising the steps of:a. detecting a zero crossing of said AC input voltage;b. preventing application of said AC input voltage to said electrical load for a predetermined length of time;c. supplying said AC input voltage to said electrical load at a predetermined angle of conduction; andd. repeating steps (a) through (c) so that with each iteration of said steps the length of time in which AC input voltage is prevented from being applied to said electrical load varies while the angle of conduction in which AC input voltage is supplied to said electrical load varies, which increases the time said AC input voltage is supplied, until said AC input voltage is fully applied to said electrical load.