DE1588434C

DE1588434C - Power supply device for a motor vehicle

Info

Publication number: DE1588434C
Authority: DE
Inventors: Maurice James Harborne Birmingham Wright (Großbritannien)
Original assignee: Joseph Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Publication date: 1972-11-30

Description

erzeugt, steigt das Potential an der Leitung 21 auf die Höhe des positiven Potentials der Batterie 11 an, und die Kontrollampe 25 erlischt. Trotzdem fließt immer noch Strom durch den Widerstand 19 und die Feldwicklung 23. Der volle Strom in der Feldwicklung 23 fließt so lange, bis die Spannung zwischen den Leitungen 12,13 einen vorbestimmten Wert erreicht. Sobald dieser Wert erreicht ist, wird die Zenerdiode 17 gezündet und leitet einen Basisstrom zum Steuertransistor 18. Dieser wird hierdurch eingeschaltet und leitet den Basisstrom vom Leistungstransistor 22 ab, so daß dieser gesperrt wird und den Strom durch die Feldwicklung 23 unterbricht. Infolgedessen wird auch die Erzeugung der Ausgangsspannung des Wechselstromgenerators 14 beendet.generated, the potential on line 21 rises to the The level of the positive potential of the battery 11 and the control lamp 25 goes out. Even so, it always flows current through the resistor 19 and the field winding 23. The full current in the field winding 23 flows until the voltage between lines 12, 13 reaches a predetermined value. As soon as this value is reached, the Zener diode 17 is ignited and conducts a base current to the control transistor 18. This is switched on and derives the base current from the power transistor 22, so that this is blocked and the current through the field winding 23 interrupts. As a result, will too the generation of the output voltage of the alternator 14 stops.

Zwischen dem Kollektor des Leistungstransistors 22 und der Basis des Steuertransistors 18 ist eine Rückkopplung vorgesehen. Diese Rückkopplung besteht aus der Reihenschaltung eines Kondensators 28 und eines Widerstandes 29. Infolge der Rückkopplung arbeiten die Transistoren 18,22 als Oszillator.Between the collector of the power transistor 22 and the base of the control transistor 18 is a Feedback provided. This feedback consists of the series connection of a capacitor 28 and a resistor 29. As a result of the feedback, the transistors 18, 22 work as an oscillator.

In einem Zustand ist der Leistungstransistor 22 voll eingeschaltet und der Steuertransistor 18 abgeschaltet, während in einem zweiten Zustand der Steuertransistor 18 voll eingeschaltet und der Leistungstransistor 22 abgeschaltet ist. Das Verhältnis der In one state, the power transistor 22 is fully switched on and the control transistor 18 is switched off, while in a second state the control transistor 18 is fully switched on and the power transistor 22 is switched off. The ratio of

ίο Einschalt- und Ausschaltdauer der Transistoren 18, 22 ist von dem Verhältnis der Leit- und Sperrzeiten der Zenerdiode 17 abhängig, das wiederum von der Spannung zwischen den Leitungen 12,13 bestimmt wird. Der Regler der Stromversorgungseinrichtung ist so eingestellt, daß über den Strom in der Feldwicklung 23 die Spannung zwischen den Leitungen 12,13 im wesentlichen konstant gehalten wird.ίο switch-on and switch-off duration of the transistors 18, 22 is dependent on the ratio of the conducting and blocking times of the Zener diode 17, which in turn depends on the Voltage between lines 12,13 is determined. The regulator of the power supply device is adjusted so that the voltage between the lines 12,13 via the current in the field winding 23 is kept essentially constant.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

1 21 2

Patent claim · ^a power supply device of the initially ge

called Art to improve that ye

Power supply device for a motor vehicle operating state monitored on a control lamp tool, consisting of a direct current excitation, which can only be used in the absence of a generator chip alternating current generator, a bridge equation lights up.

judge and a backup battery as well as a power supply in the field winding of the alternating current input type mentioned according to the invention thereby counter generator controlling transistor regulator, which triggers that the base of the power transistor over the Power transistor with the field winding in series as a control lamp trained resistor and the and its control transistor with its base io ignition switch is connected to the battery voltage and that via a zener diode and a voltage divider in parallel to the series circuit of the resistor, is due to the battery voltage at which the control switch, the ignition switch and one half of the bridge transistor an additional half of a bridge transformer via a resistor and a signal rectifier is connected to the battery terminals and has a rectifier connected to conduct, in which the power transistor is only activated at 15 when the alternator is at the rated voltage switched ignition switch into the conductive feed.

stand is controllable, thereby marked- In the following the invention is based on a

draws that the base of the power tran- a circuit diagram showing drawing closer ersistor (22) above which is shown as a control lamp.

deten resistor (25) and the ignition switch (26) 20 A battery 11 of a motor vehicle is via a is connected to the battery voltage and that parallel to positive and negative supply lines 12 and the series circuit of the resistor (25), 13 connected to an alternating current generator 14, the ignition switch (26) and one half of the The alternator has a bridge-bridge rectifier an additional half (27) rectifier. Between the lines 12,13 is a a bridge rectifier, which is connected in this way 35, consisting of two resistors 15, 16, that it conducts when the alternating current generation divider is switched. At the junction of the rator (14) delivers the nominal voltage. two resistors 15, 16 is a Zener diode 17

connected, which leads to an n-p-n transistor 18 operating as a control transistor. The emitter

30 of the control transistor 18 is connected to the line 13, while the collector via a resistor 19 is connected to line 21 and

The invention relates to a power supply also connected to the base of a second, as Lcistungsgungseinrichtung for a motor vehicle, consisting of transistor working, npn transistor 22 connected to a DC-excited alternating current generator, the emitter of which is on line 13. A bridge rectifier and a buffer battery collector of the power transistor 22 is connected to the power transistor regulator, generator controlling the current in the field winding of the device 21 via a field winding 23 of the alternating current alternator. The field winding 23 is bridged by its power transistor with the field winding in a diode 24. In addition, the series is connected and its control transistor with its 40 line 21 is connected to the line 12 via a control base via a Zener diode and a voltage lamp 25 and an ignition splitter connected in series to the battery voltage, in which the switch 26 is connected . In order to create a current path for the control transistor via a resistor and a field winding 23, even in the event that a switch is connected to the battery terminals, the control lamp 25 burns out, a resistor can be switched in parallel to and in which the power transistor is only switched on ,
switched ignition switch to the conductive state. To the series connection of control lamp 25 and

is controllable. Bypassing ignition switch 26 is a device

■ Provided on power supply devices with voltage that regulate the potential of line 21 the requirement is that the battery increases that of the positive battery terminal when the voltage is monitored as closely as possible and dip 50 alternating current generator 14 an output voltage Power supply device with as little supplies as possible. This facility consists of three additional power dissipation is working. These requirements met borrowed diodes 27, through which the line 21 to the a known power supply device of the one-phase points of the alternator 14 angang mentioned type (USA.-Patent 3 129 378), is closed!

because with this known power supply device, current flows continuously through the evaluation If the battery voltage is at an ohmic level 15, 16 of the voltage divider. The resistances Voltage divider, the voltage drop of which is the control 15, 16, however, are dimensioned so that their energy transistor of the voltage regulator taps immediately. loss is negligibly small. When the Zünd-Solange the battery voltage is still its setpoint switch 26 is closed, current flows through the has not reached, flows only through the voltage 60 control lamp 25, the resistor 19 and the base divider a low current. Further power loss occurs in the emitter path of the power transistor 22, whereby does not appear in the controller. . . the power transistor 22 is turned on and the

In addition to the requirements mentioned, there is also a circuit from line 21 to line 13 via desired, the respective operating state of the charging field winding 23 closes. After switching through facility to monitor. In the case of the known charging 65 of the power transistor 22, the control lamp lights up device, this monitoring option is not 25 as a result of the field winding 23 and the given. Control lamp 25 current flowing on. Once the

The invention is therefore based on the object, alternating current generator 14 an output voltage