Showing papers on "State of charge published in 1971"
Patent•
17 Dec 1971
TL;DR: In this article, the conduction angle is determined from the open-circuit battery potential and the previous charging history of the battery obtained from potential sensing circuits, and a potential control circuit for determining the rate of charge includes a resistor connected to the output terminal that is bypassed when the average value of the signal on the collector of a transistor having its base connected to a transistor exceeds a predetermined value.
Abstract: A circuit for battery charging includes an SCR that is periodically gated on for a duration corresponding to the state of charge of the battery, being gated on for only a short interval when the battery is essentially fully charged to keep it charged. The conduction angle is determined from the open-circuit battery potential and the previous charging history of the battery obtained from potential sensing circuits. A pedestal and cosine modified ramp circuit triggers the SCR''s through capacitors with a resistor intercoupling the SCR gate and cathode electrodes. Circuitry prevents the unijunction transistor in the latter circuit from remaining latched on. A potential control circuit for determining the rate of charge includes a resistor connected to the output terminal that is bypassed when the average value of the signal on the collector of a transistor having its base connected to the output terminal exceeds a predetermined value. Diodes intercouple the SCR''s and the emitter of the latter transistor for providing operating potentials to the circuits and a starting charging current to the output terminal when a connected battery is fully discharged.
8 citations
Patent•
06 Jan 1971
TL;DR: In this article, a storage battery is supplied from a charging unit, which is switched off when semiconductor temperature sensing elements inside and outside the battery indicate by differences in voltage drop a change in relative temperatures to operate a control amplifier, which may also influence a state of charge indicator.
Abstract: 1,218,025. Electric control systems. PLESSEY CO. Ltd. 9 March, 1970 [19 July, 1967], No. 33279/67. Heading H2H. A storage battery 1 is supplied from a charging unit 2 which is switched off when semiconductor temperature sensing elements 4, 5 respectively inside and outside the battery 1, indicate by differences in voltage drop a change in relative temperatures to operate a control amplifier 6 which may also influence a state of charge indicator 7. The temperature difference will occur when a battery particularly a nickel-cadmium battery, is fully charged and the apparatus will provide charging pulses each time the temperature differential decreases. The charging unit 2 provides a constant changing current due to transistors 8, 9, Zener diode 11 and resistors 11, 12 and the switch 13 is a transistor which conducts when the voltage from the amplifier 6 exceeds a predetermined value.
1 citations
Patent•
22 Sep 1971
TL;DR: In this paper, the state of charge of a battery is determined by counting 1 pulses, either additively or subtractively, at a frequency proportional to the current 2 flowing through the battery, the pulses being produced by a follow-up loop in which a magnetic field produced by the battery current is opposed by a field generated by pulses from a shaper 7, the difference between the fields being detected by a hall plate 4 whose output voltage controls a pulse producing oscillator 6 which also controls the pulse shaper.
Abstract: 1,247,432. Selective signalling. ALLMANNA SVENSKA ELEKTRISKA AB. 28 Feb., 1969 [29 Feb., 1968], No. 10821/69. Heading G4H. The state of charge of a battery is determined by counting 1 pulses, either additively or subtractively, at a frequency proportional to the current 2 flowing through the battery, the pulses being produced by a follow-up loop in which a magnetic field produced by the battery current is opposed by a field produced by pulses from a shaper 7, the difference between the fields being detected by a hall plate 4 whose output voltage controls a pulse producing oscillator 6 which also controls the pulse shaper. The charge/count characteristic of the circuit is linearized by modifying the charge content of the pulses produced by the shaper 7 in accordance with the direction and magnitude of the battery current.
1 citations