KR960013547B1 - Voltage regulate circuit of the ac generator for a vehicle - Google Patents

Abstract

The circuit controls 'turn-on' or 'turn-off' of a transistor(66) with the output voltage of a comparator(62) wherein, the base is connected with the terminal (1) of a zener diode(58), and the common connection point(75) of voltage distributing resistors(51,52) is connected with the (+) terminal of a temperature distributing diode(58) in a signal amplifying transistor(61): the (-) terminals of the diodes(58,59) are connected with the terminal (2) in common and the emitter is grounded and the collector is connected to a direct current source through a resistor(53) and to the base through a condenser(60); and in the comparator(62), the (+) input terminal voltage of the comparator(62) is increased and decreased suddenly through a positive feedback and amplifying the forward voltage drop of the diode(58) is amplified with the transistor(61).

Description

Voltage regulation circuit of vehicle alternator

1 is a circuit diagram showing a conventional voltage regulation circuit.

2 is a circuit diagram showing one embodiment of the present invention.

3 is a block diagram showing a triangular wave generating circuit portion constituting a reference voltage generating portion in another embodiment of the present invention.

Figure 4 (a) (b) is a waveform diagram of the signal generated in the collector of the point A, B point and the excitation power transistor in one embodiment of the present invention.

5 is a waveform diagram of a signal appearing at a point A, a point B and a collector of an excitation power transistor in another embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: alternator 2: rectifier

2a: tridiode 3: voltage regulation circuit

4: storage battery 5: keyswitch

6: lamp 101: stator winding

102: field wire 305: female power transistor

301,302: Voltage divider resistor 303: Zener diode

304: control transistor 7: the present invention

51,52: Reference voltage distribution resistor 58: Zener diet

59: temperature gradient characteristic diode 305: excitation power transistor

60 capacitor 61 amplifying transistor

62: comparator 3,64: resistance for reference voltage distribution

96: control transistor 68: excitation power transistor

71: reference voltage generator

71`: Triangular wave generating circuit part

According to the present invention, a voltage regulating circuit for a vehicle alternator configured to have a positive feedback on a comparator for stable generation voltage and to prevent burnout and loss reduction of an excitation power transistor, and to have a temperature gradient characteristic with one temperature gradient diode and one transistor. It is about.

Conventionally, as shown in FIG. 1, the three-phase alternating current of the alternator (1) and the alternator (1) with the field winding (102) for generating magnetic flux and the fixed winding (101) in which the three-phase alternating current is induced The rectifier 2 for full-wave rectification, the voltage regulating circuit 3 for regulating the field current of the field winding 102, the lamp 6, the key switch 5, and the storage battery 4 are connected to each other. When the key switch 5 is turned on, current flows through the path of the battery 4, the key switch 5, the alarm lamp 6, the field winding 102, and the excitation power transistor 305. The generator 1 generates electricity.

When the power generation voltage of the generator 1 is greater than the voltage of the storage battery 4, current flows to the field coil 102 by the voltage at the output side of the tridiode 202, and the alarm lamp 6 is turned off.

In this state, when the power generation voltage rises and the voltage across the resistor 302 of the voltage distribution resistors 301 and 302 becomes equal to or greater than the control voltage of the zener diode 303, a current flows rapidly in the zener diode 303. The control transistor 304 of the excitation transistor 305 through which the base current flows is 'turned on'. Accordingly, since the transistor 305 is 'turned off', the field current of the field winding 102 is cut off to reduce the generated voltage. Done.

When the power generation voltage decreases, the voltage across the resistor 302 becomes less than or equal to the zener voltage of the zener diode 303 so that the zener diode 303 and the transistor 304 are in a non-conductive state, and thus the base current through the resistor 306. The transistor 305 flowing through is turned "on" so that the field current flows to stop the power generation, and the power generation voltage is maintained at a constant level while repeating such an operation.

The voltage adjusting circuit 3 adjusts the generated voltage by detecting the generated voltage with the zener diode 303 and turning the transistor 304 'turn on' or 'turn off', if the frequency of the ripple component of the generated voltage is high. In this case, the switching frequency of the transistor 305 is also rapidly increased to increase the loss of the transistor 305 and increase the risk of burnout, and the zener diode 303 is initially caused by the voltage across the resistor 302 near the zener voltage. There is a problem that a ringing phenomenon occurs in which the conduction state of the substrate becomes unstable at the high frequency.

In addition, it is necessary to adjust the power generation voltage which is the charging voltage applied to the storage battery 4 according to the change of the ambient temperature, but the circuit part of this function is lacking in the conventional voltage regulation circuit 3.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its purpose is to connect a temperature gradient diode and a zener diode in series between the base and the common connection point of the two voltage distribution resistors, the emitter is grounded, and the collector is connected to the resistor. Connect to the DC power source through the capacitor and connect to the base through the capacitor.In the comparator, the (+) input terminal is connected to the collector of the transistor via the resistor, the (−) input terminal applies a reference voltage and the output terminal The excitation power transistor is connected to the base of the switching transistor, and at the same time, the resistor is connected to the collector of the amplification transistor to be positive feedback, thereby stabilizing the power generation voltage, and preventing the burnout of the excitation power transistor. The temperature gradient of the temperature gradient diode A voltage regulating circuit of an on-vehicle alternator connected to amplify a forward voltage drop variation with the amplifying transistor is provided.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

One embodiment of the present invention is a vehicle alternator that is operated by connecting the alternator 1, the rectifier 2, the battery 4, the key switch 5, the alarm lamp 6 as shown in FIG. In the voltage regulating circuit, the voltage distribution resistors 51 and 52 are connected between the terminal ① of the warning lamp and ground, and the terminal ① of the zener diode 58 at the base of the transistor 61 of the emitter-grounded amplifier. Connect the (+) terminal of the temperature gradient diode 58 to the common connection point 75 of the voltage distribution resistors 51 and 52, and the (-) terminal and the terminal ② of the diodes 58 and 59. The common connection is made, the emitter is grounded, and the collector is connected to the DC power supply (Vcc) via the bias resistor (53), and is connected to the base via the capacitor (60), and in the comparator (62) of the operational amplifier (+) The input terminal is connected to the collector of the transistor 61 via a resistor 69 and has a negative voltage applied thereto. The terminal is connected to the connection point 74 of the reference voltage distribution resistors 63 and 64, which are the reference voltage generator 71, and the output terminal is connected to the DC power supply Vcc via the resistor 55 and at the same time, the resistor 54 The base is connected to the output terminal of the comparator 62 via the resistor 57 in the control transistor 66 of the excitation power transistor 68, and the collector is connected to the bias resistor. Via 56, the output of the rectifier 2 tridiode 2a is connected to a connected connection point 77 and the emitter is grounded.

In the excitation power transistor 68, the base is connected to the collector of the transistor 66, the collector is connected to the connection point 77 via the diode 70, and at the same time, to the terminal ① of the magnetic winding 102, and the emitter is grounded. do.

Referring to the operation in one embodiment of the present invention configured as described above, the key switch (5) 'on' storage battery (4), key switch (5), alarm lamp (6), field winding (102). When the field current flows through the excitation power transistor 68, the generator 1 starts to generate power. When this state continues and the power generation voltage rises, the voltage between the both ends of the reference voltage resistor 52 becomes a temperature gradient characteristic diode ( 58), amplified by the transistor 61 via the zener diode 59, and the amplified voltage is input to the (+) input terminal of the comparator 62, and the reference voltage is input to the (-) input terminal so that both voltages are input. This is compared.

The waveforms appearing on the negative input terminal B of the comparator 62, the A point that is the collector of the transistor 61, and the collector of the transistor 68 are as shown in FIG. If the point voltage amplified by the transistor 61 is higher than the point voltage as the voltage increases, a 'high' voltage appears at the output terminal of the comparator 62. Since the voltage is positive feedback through the resistor 54, the point voltage is The level rises sharply. Therefore, even if a ripple voltage resulting from the ripple component of the generated voltage is applied to the point A, that is, the (+) input terminal of the comparator 62, as shown in FIG. 4, the sharp rise of the point voltage and the characteristics of the comparator 62 are shown. The output terminal 62a of 62 does not generate a high frequency ringing phenomenon in which waveform vibration occurs until the steady state is reached.

In this state, the control transistor 66 is 'turned on' and the excitation power transistor 68 is 'turned off' so that the field current is cut off in the field winding 102 so that the generated voltage is decreased, and the A point voltage continues to decrease. Since the voltage of the comparator 62 becomes lower than the point B voltage, which is the reference voltage input terminal of the comparator 62, the output voltage of the comparator 62 becomes a 'low' level close to 0 [V], and this voltage is positively fed back through the resistor 54. The point A voltage almost decreases. Therefore, since the point B voltage and the point A voltage which are the reference input voltage in the comparator 62 are momentarily out of the same state, the high frequency ringing phenomenon does not occur as in the prior art.

In this state, the transistor 66 is 'turned off' and the transistor 68 is 'turned on' so that the field current flows through the field winding 102 so that the generator 1 resumes power generation and the power generation voltage is raised again. .

In addition, when the ambient temperature is increased, the power generation voltage is reduced, and when the ambient temperature is low, a temperature gradient characteristic for increasing the power generation voltage is required. The temperature gradient characteristic diode 58, the zener diode 59, and the transistor 61 are described above. Configure a circuit that satisfies the characteristics.

In the diode 58 having a negative temperature gradient of -2mv / ° C, the forward voltage drop changes with temperature, and the transistor 61 changes its base current and amplifies the input current. The voltage at the point changes, and this temperature gradient characteristic value can be adjusted by appropriately selecting the resistance values of the resistors 51 and 52 for voltage distribution. Typically, the temperature gradient characteristic required for the voltage regulator is -7 to -12mv / ° C. To satisfy this characteristic with only a diode, four to six series-connected diodes are required, but in the present invention, the temperature gradient diode 58 Since the output signal is amplified by the transistor 61, the same operation can be performed only by one diode 58 and one transistor 61.

Another embodiment of the present invention is made by replacing the reference voltage generator 71 shown in FIG. 2 with the triangular wave generator circuit 71 shown in FIG. 3, in the case of FIG. While the switching frequency of the excitation power transistor 68 is determined, in another embodiment, the switching frequency is determined according to the frequency of the triangular wave (point B voltage) shown in FIG.

In the case of the embodiment of the present invention shown in FIG. 2, the point of the waveform shown in FIG. 4 (a) and the voltage of the point are compared in the comparator 62 so that the 'high' or 'low' level is alternated. According to the voltage, the two transistors 66 and 68 are 'turned on', 'turned off' or 'turned off' and 'turned on' so that the square wave or pulse shown in FIG. 4 (b) is applied to the collector of the transistor 68. If 'high' is the 'turn off' state because the field current is cut off in the field winding 102, if the 'low' is 'turned on' field current flows through the field winding (102).

Therefore, the switching frequency of the transistor 68 varies according to the field, that is, the power generation voltage according to the change in the rotational speed of the rotor. However, in the other embodiment, as shown in FIG. Switching to a constant frequency reduces the loss of the excitation power transistor and stabilizes the generation voltage.

The present invention as described above prevents the occurrence of burnout, loss, and unstable power generation voltage of the transistor 68 by the high frequency switching of the excitation power transistor 68, so that the voltage adjusting function is stable and the reliability of operation is improved. In addition, since the temperature gradient characteristic portion is simply composed of the temperature gradient diode 58, the zener diode 59, and the transistor 61, it has an excellent effect in terms of economical efficiency.

Claims (3)

Field generator of magnetic field winding 102 for magnetic flux generation and stator winding 101 in which three-phase AC electromotive force is induced, alternator 1 for full-wave rectification of three-phase AC, field winding 102 In the voltage regulating circuit of the automotive alternator operating the voltage adjusting circuit 3, the lamp 6, the key switch 5, and the storage battery 4 for controlling the current, the signal amplification transistor 61 has a zener diode at the base. Terminal (1) of (58) is connected to the common connection point (75) of the voltage distribution resistors (51) and (+) terminal of the temperature gradient diode (58) and the ( The terminal and terminal ② are connected in common, the emitter is grounded, and the collector is connected to the DC power supply through the resistor 53 and at the same time through the capacitor 60 to the base, and the (+) input terminal of the comparator 62 is connected. Is connected to the collector of the transistor 61 via a resistor 69 and is connected to the negative terminal of the reference voltage generator 71. A quasi-voltage is applied and the output terminal is connected to the base of the control transistor 66 of the excitation power transistor 68 via the resistor 57, and is connected to the collector of the transistor 61 via the feedback resistor 54. By connecting to feedback, the positive input voltage of the comparator 62 is rapidly increased and decreased through positive feedback, and the forward voltage drop of the diode 58 is amplified by the transistor 61 to output the output voltage of the comparator 62. The voltage control circuit of the automotive alternator, characterized in that for controlling the 'turn on' or 'turn off' of the transistor (66). The reference voltage generator 71 has two reference voltage distribution resistors 63 and 64 connected in series between a DC power supply and a ground, and a common connection point B of the comparator 62 is used. A switching frequency of the transistor (68) which is connected to an input terminal and varies according to a power generation voltage. 2. The transistor of claim 1, wherein the reference voltage generator 71 comprises a triangular wave generator circuit 71 'and its output terminal is connected to the negative input terminal of the comparator 62 to drive the transistor 68 at a constant frequency. Voltage regulation circuit of the automotive alternator, characterized in that for switching.