JPH0199499A - Field voltage regulator of ac generator - Google Patents

Abstract

PURPOSE:To make a protective diode unnecessary by using a field-effect transistor for the main part of a field voltage regulating circuit. CONSTITUTION:In immediately after the starting of a motor, the output voltage of an output coil 51 is low. For this reason, a controlling transistor 70 is cut off. The gate is supplied to FET 35 through an auxiliary coil 52 to the resistance 71 by cutting off of the controlling transistor 70, continuity of FET 35 is established and the current flows to the field coil 2. In case the output voltage is getting high, continuity of the transistor 70 is established and FET 35 is cut off so that the current does not flow to the field coil 2 and the output voltage lowers. Accordingly, something equivalent to diode characteristically is incorporated into the FET to be used so that it is not necessary to connect a protective diode newly.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a field voltage adjustment device for an alternating current generator, and is particularly suitable for adjusting the field voltage of an alternating current generator, which is relatively small and automatic. Regarding equipment.

[Conventional technology]

FIG. 3 shows a conventional example. The conventional example shown in FIG. 3 includes a generator output coil 51, an auxiliary coil 52, and a field coil 53.
is disclosed. The output coil 51 is connected to the main switch 51
It is connected to the load 80 via A. A part of the output from the output coil 51 is rectified by a rectifier circuit 54 and used for field control. Further, the output of the auxiliary coil 52 is rectified by a rectifier circuit 55 and applied to the field coil 53 as a field power source.

To explain this in more detail, a capacitor 56 is connected to the output side of the rectifier circuit 55 related to the auxiliary coil 52, and a series circuit of the field coil 53 and a transistor 57 is also connected. A diode 58 is connected in parallel to the transistor 57, and a flywheel diode 60 is connected in parallel to the field coil 53. A capacitor 62 and two series-connected resistors 63 and 64 are connected in parallel to the output side of the rectifier circuit 54 via a resistor 61. One end of a resistor 67 is connected to the connection point of the resistors 63 and 64 via a Zener diode 65. The other end of the resistor 67 is connected to the rectifier circuit 54 in common.
．． 55 (hereinafter referred to as the ground line).

A diode 69 is connected in parallel to the resistor 67, and
A transistor 70 is connected to the Zener diode 65.
The base is connected. Transistor 70 has its emitter connected to the ground line, and its collector connected to one end of resistor 71 and the base of transistor 72. The collector of this transistor 70 is connected to one end of a resistor 71 and the base of a transistor 72. The other end of the resistor 71 is connected to the positive pole side (hereinafter referred to as "positive line") of a rectifier circuit 55 connected to one end of the field coil 53. The emitter of transistor 72 is connected to the base of transistor 57.

When the load 80 is a light bulb or the like and does not have a phase advance characteristic, the rotor of the generator is rotated and vibrated, and the output coil 51
When an output voltage is generated, this output voltage is supplied to a load 80 such as a light bulb (not shown). At the same time, this output is connected to the rectifier circuit 54. The alternating current is smoothed by a resistor 61 and a capacitor 62, and is supplied to resistors 63 and 64. Resistor 63.
Since the connection point 64 is connected to the base of the transistor 70 via the Zener diode 65, when the divided voltage exceeds a certain value (Zener voltage), the transistor 70 becomes conductive.

When the output voltage generated in the output coil 1 is lower than the preset voltage, that is, the operating voltage of the Zener diode 65 in the circuit of FIG. Then, the field coil 53 is connected via the conductive transistor 57.
It will be supplied to the system to generate electricity. When the output voltage rises and energizes Zener diode 65, transistor 70 conducts, cutting off transistor 72 and therefore transistor 57, limiting the current to field coil 53 and reducing the output voltage of the generator. lower. This process is repeated as appropriate to adjust the voltage.

[Problem that the invention seeks to solve]

However, in the above conventional example, the connected load 8
0 is a capacitive load etc., a back electromotive force may be generated in the field coil 53, and the above-mentioned transistors 57, 7
A diode 58 was required as a protection circuit for 0.76. Also, the Darlington connected transistor 57
, there was always a need for something with a large current capacity. For example, if a transistor 57 with a current of zero current of 110 (A) is used, the permissible value for pulses is about 15 (A), but from a safety standpoint, in reality, a transistor with a larger current capacity must be used. It becomes. Furthermore, regarding the resistor 71 connected in series to the transistor 70,
Since a relatively large base current must be passed through the Darlington connected transistor 72.57, a large wattage rating was required. For this reason, the above-mentioned conventional example has disadvantages in that overall power consumption is large and components are severely deteriorated due to heat generation.

[Purpose of the invention]

The purpose of the present invention is to improve the disadvantages of the above conventional example,
To provide a field voltage regulator for an alternating current generator that consumes less power, has stable operation, and is durable.

[Means for solving problems]

Therefore, in the present invention, a field power supply circuit section that rectifies the output from the auxiliary coils separately and supplies them to the field coil, and a field power supply circuit section that is interposed between the field power supply circuit section and the field coil and output a field voltage adjustment circuit section that is energized by the output of the coil, and which is connected to a field effect transistor connected in series to the field coil; It consists of a capacitor and a Zener diode each connected in parallel between the gates, and an excitation start control section that applies an auxiliary coil output to the gate of the field effect transistor after startup to set the field effect transistor in an operating state. This aims to achieve the above-mentioned purpose.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

The embodiment shown in FIG. 1 includes a field power supply circuit section l of an alternating current generator, a field coil 53, and a field voltage adjustment circuit section 3.

The field power supply circuit section 1 has the auxiliary coil 52 as its main part, as in the case of the conventional example described above.

The output of the auxiliary coil 52 is rectified by a rectifier 55 and applied to the field coil 53.

Further, the output from the output coil 51 is rectified by a rectifier 54 and used for excitation start control for the field voltage adjustment circuit section 3. In this case, output coil 5
The waveform e of the output voltage 1 is shown in FIG. 2 (1), and the waveform e2 on the output side of the rectifier 54 is shown in FIG. 2 (2).

The field voltage adjustment circuit section 3 includes a field effect transistor 35 connected in series to the field coil 53, a capacitor 36 and a Zener diode 37 connected in parallel between the drain and gate of the field effect transistor 35, and a The output of the auxiliary coil 52 is connected to the field effect transistor 35.
and an excitation start control section 4 that applies voltage to the gate of the field effect transistor 35 to set the field effect transistor 35 in an operating state.

Of these, the excitation start control section 4 divides the voltage of the output from the output coil 51 rectified by the rectifier 54 into resistors 63 and 64, and the potential of the downstream voltage dividing resistor 64 of these through the Zener diode 65. The control transistor 7o is connected to the base of the control transistor 7o, and a resistor 67 and a check diode 69 are connected in parallel between the base and emitter of the control transistor 7o. The collector end of the control transistor 7° is connected to the upstream output end (positive line) of the rectifier 55 for the auxiliary coil 52 via the resistor 71.
Similarly, the emitter end is connected to the downstream output end (negative line) of the rectifier 55 for the auxiliary coil 52.

The collector end of the control transistor 70 is connected to the gate of the field effect transistor (hereinafter referred to as rFET) 35 described above. A drain end of the FET 35 is connected to the downstream side of the field coil 53. This field coil 5
3, a non-return diode 60 is connected in parallel.

FIG. 3(3) shows the output waveform of the control transistor 70 described above, and FIG. 3(4) shows the waveform of the voltage applied to the field coil 53. The other configurations are the same as the conventional example described above.

Next, the operation of the above conventional example will be explained.

Immediately after starting the generator, the output voltage of the output coil 51 is low. Therefore, as in the case of the conventional example described above, the control transistor 70 is cut off. On the other hand, by shutting off the control transistor 7o, the auxiliary coil 52
A voltage equal to or higher than the threshold voltage is supplied to the gate of the FET 35 through the resistor 71. As a result, the FET 35 becomes conductive, allowing current to flow through the field coil 2 and increasing the output voltage. Conversely, when the output voltage is high, the transistor 7o is conductive and does not supply gate voltage to the FET 35, and the FET 35 is cut off, so no current flows through the field coil 2 and the output voltage decreases. By repeating this process, the output voltage is adjusted to a constant value.

Here, the FET used has a built-in one corresponding to the diode 58 in FIG. 3 due to its characteristics, so there is no need to connect a new diode. In addition, the tolerance value for pulse current is high, and it is 38 (A) when the current is 9°6 [A].
), which far exceeds the characteristics of transistors. Furthermore, if the on-resistance is fixed and a current of 1 [A] is passed, the voltage drop will be 0 if the on-resistance is 0.6 [Ω].
It is small at ゜6 [v]. In addition, since the gate voltage is regulated by the diode 37, the current is limited due to its characteristics, and even if the output is short-circuited, for example, a large current will not flow. For example, if the gate voltage is regulated to 5 [V], the drain current will not flow more than 6 [A3] (the characteristic values are just an example).

As for the resistor 71, since the FET 35 is controlled by current, there is no need to pass a large current, and it is sufficient to have a large resistance value and a small wattage.

In FIG. 1, the capacitor 36 prevents fluctuations in the gate threshold voltage due to changes in the voltage of the auxiliary coil 52, and
35 has the effect of improving the rise of conduction.

〔Effect of the invention〕

As described above, according to the present invention, since a field effect transistor is used in the main part of the field voltage adjustment circuit, the protective diode required in the conventional example described above is no longer required, and the tolerance value for pulse current is The large current capacity makes it possible to use field effect transistors with relatively small current capacities, and the low voltage drop means less power loss and significantly increased durability. The gate voltage is regulated by the action of the Zener diode connected to the gate, which limits the current.This eliminates the inconvenience of a large current flowing even if the output is short-circuited, thus preventing accidents such as circuit burnout. Provided is an unprecedented and excellent field voltage adjustment device for an alternating current generator, which can effectively prevent the problem, and can reduce the size and cost of the entire device because it is composed of members with an overall small capacity. can do.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing one embodiment of the present invention, and Fig. 2 is a circuit diagram showing an embodiment of the present invention.
FIG. 3 is a diagram showing waveforms at each part in the figure, and a circuit diagram showing a conventional example. 1... Field power supply circuit section, 3... Field voltage adjustment circuit section, 4... Excitation start control section, 35
...... Field-effect transistor, 36...
・Capacitor, 37... Zener diode,
51...Output coil, 52...Auxiliary coil, 53...Field coil. Patent applicant Suzuki Motor Co., Ltd. Procedural Amendment (
Voluntary) Commissioner of the Japan Patent Office Yoshi 1) Moon Takeshi 1, Indication of the case Patent application No. 25661 of 1985
No. 4, No. 3, Relationship with the case of the person making the amendment Patent applicant address: 300-4 Takatsuka, Kamimura, Hamana-gun, Shizuoka Prefecture
, Agent 101 Telephone (03) 86'2-65
206, Contents of amendment (1), “Rotation” and “Rotation” in the fourth line of the fourth page of the specification
The word ``vibration'' written between ``is driven'' should be corrected to ``drive.'' (2) The word "each" written at the beginning of page 6, line 14 of the specification is deleted. (3) "53 on page 9, line 9 of the specification,
” and “Die” and “for check” is deleted, and the following sentence in “ ” is inserted in the deleted place. "Flywheel" (4), "35" on page 11, line 3 of the specification
"Current" written between and "control" is corrected to "voltage." (5) Among the drawings originally attached to the application, Figure 2 is amended by replacing it with Figure 2 of the attached sheet. that's all. Figure 2

Claims (1)

[Claims] (1) A field power supply circuit section that rectifies the output from the auxiliary coil and supplies it to the field coil, and a field power supply circuit section that is interposed between the field power supply circuit section and the field coil and outputs the output from the output coil. a field voltage adjustment circuit section that is energized to operate, and the field voltage adjustment circuit section is connected between a field effect transistor connected in series to the field coil and the drain-gate of the field effect transistor. An alternating current comprising a capacitor and a Zener diode that are connected in parallel, and an excitation start control unit that applies the auxiliary coil output to the gate of the field effect transistor to set the field effect transistor to an operating state. Generator field voltage regulator.