Voltage regulation circuit for a solar cell charging system
AssigneeLucas Industries Limited
InventorMaurice J. Wright
Life of this patent
Estimating the term…
Abstract
A voltage regulation circuit includes an active integrator circuit which generates an output signal representing the time integral of the error between the voltage across a load and a reference voltage. The integrator circuit output is connected to a series of voltage comparators (each having hysteresis) each of which controls one of a series of separate switch elements each controlling a proportion of the total current flow from a source to the load.
Claims16
A voltage regulation circuit comprising a battery voltage sensing means including an electronic active integrator circuit producing an output representing the time integral of difference between the voltage of a battery under charge and a reference voltage, a plurality of comparator circuits comparing the output of said integrator circuit with a plurality of different reference levels, and a plurality of switch devices controlled by respective ones of the comparator circuits whereby, in use, each of said switch devices acts selectively to permit or prevent the flow of a portion of the output current from charging current source means to the battery the switch devices being sequentially operated by the comparator circuits as the fraction of the current output capability of said source means required to maintain the battery voltage and the reference voltage varies, and the integrator circuit operating so as to control the duty ratio of at least one of the switch elements.
A solar panel storage battery charging system comprising a storage battery, a plurality of solar panels for supplying charging current to the battery, a plurality of relays, each having a contact in series with a respective one of the solar panels, diode means connecting the series circuits constituted by the solar panels and associated relay contacts in a parallel array across the battery, a plurality of comparator means connected to energise the respective relays, each comparator means receiving a common charge current demand signal and a respective one of a plurality of predetermined reference level signals, whereby the comparator means are actuated successively to operate respective relays and connect the solar panels in circuit with the battery as said charging current demand signal rises, a battery voltage sensing circuit connected across the battery, a reference voltage circuit connected across the battery and an electronic active integrator circuit connected to said voltage sensing circuit and said voltage reference circuit and producing as its output and current demand signal which represents the time integral of the error between the signals received by the integrator circuit from the voltage sensing circuit and the voltage reference circuit, the output of the integrator circuit being connected to one input of each comparator circuit.
Dependencies are inferred from the claim text.