초록 ▼

A simple, low-cost technique for charge equalization of a series connected string of battery cells is provided. The secondary windings of a transformer having a single primary winding and multiple secondary windings are connected across each battery cell to be equalized. A single power converter app

A simple, low-cost technique for charge equalization of a series connected string of battery cells is provided. The secondary windings of a transformer having a single primary winding and multiple secondary windings are connected across each battery cell to be equalized. A single power converter applies a charging signal to the primary of the transformer, inducing a charging current in each secondary which is inversely related to the charge on the battery cells to be equalized. The transformer is preferably implemented as a coaxial winding transformer having low secondary-to-secondary winding coupling. The power converter is preferably implemented as a forward converter supplied with DC power from an adjustable DC power source. A source voltage provided by the DC source may preferably be adjusted during the course of charge equalization to preferentially direct charge to weaker cells. The charge equalization system may be used in combination with a bulk charging system to provide for both rapid charging of a battery string as well as equalization of the battery cells within the string.

대표청구항 ▼

A charge equalizer for equalizing the charge on two or more energy storage cells connected in series, comprising: (a) a transformer having a single primary winding and plural secondary windings, wherein each secondary winding is adapted to be connected to a one of the energy storage cells; (b) power

A charge equalizer for equalizing the charge on two or more energy storage cells connected in series, comprising: (a) a transformer having a single primary winding and plural secondary windings, wherein each secondary winding is adapted to be connected to a one of the energy storage cells; (b) power converter means for applying an equalization voltage signal to the primary of the transformer to induce a charging current in each secondary winding whose average magnitude is inversely related to a charge voltage level of the corresponding energy storage cell to equalize the charge on the energy storage cells; and (c) means for increasing a magnitude of the qualization voltage signal as the charge on the energy storage cells becomes equalized.