A voltage regulator for the battery charging generator of a motor vehicle battery charging system. The regulator is capable of detecting various fault conditions and under certain conditions will latch a fault indicator to a latched energized state. The regulator utilizes a Zener diode as a voltage reference and is arranged to accommodate Zener diodes of varying break down voltages by trimming a resistor of the regulator voltage sensing circuit. The regulator includes an internal voltage regulating device having a regulated output voltage applied to fault detecting comparators. The output voltage of the internal regulating device is a function of the particular break down voltage of the Zener diode.

Generator voltage regulator

In a wind electric plant of the type including a wind-driven propeller or the like and an alternating current alternator connected to be driven thereby to generate electrical energy for charging storage batteries or other desired use, electrical circuitry connected with the alternator and a storage battery and including controls responsive to alternator speed and battery voltage to provide a relatively constant excitation current for the field winding of the alternator from a storage battery, whereby the alternator field is fully excited at substantially all speeds of operation thereof and the need for a conventional alternator exciter is eliminated.

Wind electric plant with improved alternator field excitation

A conventional voltage regulator is modified to reduce the power output from an associated alternator type generator by lowering the field current duty cycle when the ambient temperature at the voltage regulator exceeds a predetermined critical value, to thereby prevent damage to the alternator and regulator components until the ambient temperature is reduced. A temperature responsive means is connected across the field winding of the alternator and provides an override control function to the regulating section of the regulator, whenever the ambient temperature is too high. The override control causes the closed field current switch to be opened and to be held opened for a period of time that is directly related to the value of the sensed ambient temperature above the critical value.

Voltage regulator with temperature responsive circuitry for reducing alternator output current

An automotive battery charging system includes a novel temperature compensation arrangement. The conventional input potential divider has a further resistor and a temperature compensation output transistor in series across one leg of the divider. The voltage at the base of the temperature compensation output transistor is controlled by a temperature sensing circuit so as to fall linearly with rising temperature. Resistors are adjusted in manufacture to give the required level and slope for the temperature compensation characteristic.

Automotive battery charging system

A charging control unit comprises a voltage detecting means including a first and a second resistor connected in series to an output of the armature coil, a third resistor parallelly connected to the second resistor and a temperature detecting element having a temperature coefficient, and a comparator having its one end connected to the second resistor and the other end connected to a reference voltage source. An arbitrary temperature characteristic can be set by varying the first resistor or the third resistor. At the same time, an arbitrary charging voltage can be set by changing the second resistor without changing the temperature characteristic.

Charging control unit and method for motor vehicle

A voltage regulator is disclosed for varying the output of a generator of a road vehicle by changing the current flow in its field winding. The voltage regulator device includes, as is common, a Zener diode or equivalent break-down device which, as known, conducts at a predetermined battery voltage, and serves to render a transistor conductive, which transistor, when rendered conductive, acts through further components to reduce the current flow in the field winding. In systems of this type it is commonplace to provide for temperature compensation by providing a thermistor or equivalent device in the circuit. Such device, in a known manner, serves to compensate for changes in battery temperature, as well as for the changes in temperature coefficient of the Zener diode and the transistor so utilized. However, in accordance with the instant invention, such temperature compensation is achieved by means of a simple impedance network interconnecting the Zener diode or equivalent device and the transistor, such impedance network, in effect, serving to multiply the net negative inherent temperature characteristics of the transistor by a selected amount to compensate for the net positive temperature coefficient of the Zener diode, the resultant characteristics of the voltage regulator circuit with respect to temperature being desirably negative or, at least, zero. In the specific preferred embodiment, a resistor is disposed across the base-emitter of the transistor, and another resistor is disposed in series circuit with the Zener diode. The ratio of these two resistors substantially defines a multiplication factor which enhances the net negative temperature coefficient of the transistor and serves to overcome the net positive temperature coefficient of the Zener diode.

R Nolan

Papers

Voltage regulators for use in battery charging systems