JPH02123968A - Electric-supply equipment - Google Patents

Abstract

PURPOSE:To extend the range of an input voltage by generating constant voltages through separately rectifying two kinds or more of voltage obtained by transforming AC voltage and by selecting the maximum constant voltage out of constant voltages with an instantaneous value exceeding a specified value during each cycle of transformer output. CONSTITUTION:AC input is transformed 21 to output a plurality of voltages Vac1-Vac4, which are rectified 22-25 separately to output DC voltages, which are inputted to constant-voltage circuits VR1-VR4. The circuit VR1 is composed of a reference-voltage setting Zener diode ZD1, a resistor R1 and a transistor Tr, and the circuits VR2-VR4 are formed by resistor R2-R4, diodes D2-D4 and Tr, and divided by the diodes D2-D4. Respective circuits VR1-VR4 are connected with an output terminal Vout1 via diodes D5-D8. When transformer outputs Vac1-Vac4 or rectifier outputs rise above respective set values of the circuits VR1-VR4, the maximum voltage is selected by the diodes D5-D8. Thus, even if AC input voltage is changed to the range of 50-30V, the output voltage is set at approximately 5V.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power supply device, and more particularly to a power supply device capable of obtaining a predetermined constant voltage output even if the input AC voltage varies over a wide range.

[Conventional technology]

Currently, the commercial AC power supply voltage in Japan, for example, is 100V.

It varies by country and region, such as TTOV in the United States and 220V in most European countries. Therefore, when using an electric appliance such as an electric shaver in a place where the commercial power supply voltage is different, the pre-installed step-down resistor can be inserted into or disconnected from the circuit using a switch to adapt it to the power supply voltage. It is being done. Furthermore, in radios, televisions, tape recorders, electric refrigerators, etc., the tap position of the power transformer is switched or the voltage is adjusted with a slider depending on the country or region of use.

[Problem to be solved by the invention]

However, as in the above-mentioned conventional technology, adjusting the power supply voltage by switching the step-down resistor with a switch or changing the tap position of the power transformer is troublesome and
It is impossible to adjust the voltage between the switching positions of a switch or tap or the relatively small difference in power supply voltage, and furthermore, the expected performance may not be obtained at all due to undervoltage caused by forgetting to switch or switching the switch in the wrong position. There was no
There were problems such as excessive voltage causing damage to equipment and accidents. Although SLIDAC can continuously compensate for differences in power supply voltage, it is heavy, bulky, and cumbersome for home use.

Furthermore, depending on the country or region, the quality of commercial AC power supplies is poor, and sudden voltage fluctuations may occur frequently, but it is completely impossible to deal with such voltage fluctuations using the methods described above. be. In any case, these conventional power supply voltage adjustment means or compensation means require manual setting or adjustment, and automatically compensate for differences in commercial AC power supply voltage and sudden voltage fluctuations to stabilize a predetermined constant DC voltage. It was impossible to output it in a realistic manner.

Furthermore, recently in Japan, 200V power supplies and equipment are becoming popular for home use, and even if the commercial power supply is 100V, 200V
However, there is no doubt that a power supply device that can obtain a predetermined constant DC voltage without switching using switches or taps is extremely useful.

This invention was made in view of the above circumstances, and its purpose is to be applicable to a wide range of AC power supply voltages without manual setting or switching, and to maintain a stable and predetermined power supply even in the face of large fluctuations in power supply voltage. An object of the present invention is to provide a power supply device capable of obtaining a constant DC voltage.

[Means to solve the problem]

To achieve the above object, the power supply device of the present invention uses an AC voltage v3.0 as shown in FIG. input and select n different ones (
n is an integer greater than or equal to 2).
; a voltage transformation means 11 for obtaining Vacl-1>V-+);
A rectifier 12 rectifies each of these transformer outputs v, , l to obtain n rectified outputs, and inputs each of these rectified outputs to generate a constant voltage Vs'r+(V3〒
+−+<Vs〒,) n constant voltage circuits VRi,
Output is made only from the circuit with the maximum constant voltage VSTI among the constant voltage circuits VRi where the instantaneous values of the rectified outputs become equal to or higher than the constant voltages Vst+ at each instant during each cycle of the transformed outputs Va and t. It is equipped with a maximum voltage selection circuit 13.

[Effect]

The operation of the power supply device of the present invention having the above-mentioned configuration is explained by the transformer means 1! A case in which the output terminal outputs four types of voltages, i.e., i4, will be explained with reference to FIG.

Output Vn of the voltage transformation means 11. 1 to v, 34 are the third
As shown in the figure, the rectifying means 1 has different wave height values.
2 and is rectified by the constant voltage circuit V11. ~VRt. Each of these constant voltage circuits VRi to VR4 outputs a preset constant voltage v, a, ~v, 74, respectively, and the maximum voltage selection circuit 13 corresponds to the instantaneous value of the rectified output of the rectifying means 12, respectively. Outputs only the maximum constant voltage among those that exceed the set constant voltage. That is, [. During ~t1, V-c+ is output, but from 11~[
A constant DC voltage VSTI is output during , and Vast is output between t and t. Following this, between <ts and t7, Vsv+<Vstz≦Vn,! <v3a with Vntl,
is output.

Similarly, between t 1 s and t + s (7), Vst+<Vast<Vsrs<Vsra≦Vn, a
<Vn, 3<Vn, t<v, , constant voltage v
3〒4 is output.

These constant voltages v, 71 to Vs〒4 are set to a value close to the desired final constant voltage output by making the difference between them small, for example, 0.5V. The output section of the maximum voltage selection circuit 13 may further be connected to a constant voltage circuit (final constant voltage circuit 14) whose set value is equal to or lower than Vst+.

In this way, v16. By appropriately selecting and setting Vs and Vs, the AC input voltage v1. is Vn, I
-V.

A predetermined DC constant voltage output can always be ensured even if the voltage changes significantly between 19 and 19.

〔Example〕

Hereinafter, an embodiment of the power supply device of the present invention shown in FIG. 2 will be described.

The power supply device of the illustrated embodiment has V# as a voltage transformation means.
. ~v43. Each of these tap outputs v1□ to Vnt is rectified by rectifier circuits 22 to 25, respectively, to constant voltage circuits VRi-VR.

is input. Each of the rectifier circuits 22 to 25 is composed of a diode D and a capacitor C, respectively. Note that the capacitor C may be omitted or may have a small capacity.

The voltage circuit VR+ includes a Zener diode 201. as a reference voltage setting means. It consists of a three-terminal constant voltage circuit having a resistor R1 and a transistor, and the constant voltage circuit VRi has a resistor R1.
2. Consists of a three-terminal constant voltage circuit having a diode D2 and a transistor. Similarly, constant voltage circuits VRi, VRi
are also resistors R3, R4, and diode 03. D4
It consists of a three-terminal constant voltage circuit having a transistor and a transistor.

The diodes D2 to D4 are connected in series between the base of the transistor of the constant voltage circuit VL and the base of the transistor of VRi, with this direction being the forward direction, and the reference voltage of the constant voltage circuits VR2 to VRi is determined by the voltage division of these diodes. It has gained. In this embodiment, the set reference voltage Gi5. of the constant voltage circuit VRi. IVte, VRi~V11. G;t
They are set to 5.2Vn, 5.3Vn, and 5.4V, respectively.

Diodes D5 to D8 are connected to the emitters of the transistors of these constant voltage circuits VRi to VRi, respectively, forming a maximum voltage selection circuit. That is, the transformed output Va
After c+~V□4 or their rectified outputs rise above the respective set voltages of the constant voltage circuits VRi~VRa, the set voltages of the constant voltage circuits VRi~VRi are reduced by the backflow prevention action of each diode D5~08. The highest voltage among them is V. 3. The output will be closed. In this way, the output voltage Vn, , is 0. A waveform as shown in FIG. 3 with a voltage difference of lv is obtained. In this example, an additional 5v
A final constant voltage circuit VRi is provided, which is set to
Final constant voltage output■. ,.

As a result, a constant DC voltage of 5V is obtained.

In this embodiment, AC human power Vn, is approximately 50 to 350
A constant voltage of 5V can always be obtained even if the voltage changes within the range of 5V. In addition, the voltage loss of each constant voltage circuit VRi-VRi (
The product of the voltage drop (voltage drop due to each resistor R1 to R4) and current is designed to be within the allowable loss of the three-terminal circuit of these constant voltage circuits VRi to VRt, but the voltage loss of each constant voltage circuit VRi to VR4 is small. It is clear from the above operation that this can be done. Note that the voltage value and number of secondary side output voltages may be determined as appropriate depending on the allowable loss of the three-terminal constant voltage circuit.

Although the embodiment shown in FIG. 2 was explained in the case of half-wave rectification,
As shown in FIG. 6 (al), an embodiment using forward rectification is also easy, and as shown in FIG. 6 (f), the constant voltage circuit VR
Zener diodes may be provided individually for each of t to VR4, and furthermore, it is also easy to form each of the constant voltage circuits VRi to VRi as a Darlington connection type, as shown in FIG. 6 (tel). 4 and 5 respectively show other embodiments of the power supply device of the present invention. In the embodiment of FIG. 4, a diode 040 and a capacitor C40 are provided in common for each rectified output Vat+ to Vac4 as rectifying means. In addition, two diodes ([19,DIO) and three diodes ([19,DIO]) are installed in the constant voltage circuits Vilj and Vili, respectively.
1.012.13) is completely the same as the embodiment shown in FIG. 2 except for the provision, and detailed explanation will be omitted. The embodiment shown in FIG. 5 is also completely similar to the embodiment shown in FIG. 2, except that the constant voltage circuit has the same circuit configuration as the embodiment shown in FIG.

〔Effect of the invention〕

As explained above, the power supply device of the present invention inputs the AC voltage V1m and outputs n different transformers (n is an integer of 2 or more) v, 1 (i=2 to r1; V-, + −1>V
-); rectifier means to rectify each of these transformed outputs Vmcl to obtain n rectified outputs; <vST+) n constant voltage circuits VRi, and the above-mentioned transformer output V2. ．． At each instant during each cycle, the instantaneous value of each rectified output is equal to each constant voltage v,
The constant voltage V in the constant voltage circuit VR+ which has become 71 or more
The configuration is equipped with a maximum voltage selection circuit that outputs only from the circuit with the largest STl, so it is possible to always stably obtain a specified constant DC voltage for a wide range of AC input voltages, and it is possible to obtain a constant DC voltage that is stable for a wide range of AC input voltages, and is suitable for commercial AC applications depending on the country or region. It can be adapted to the power supply voltage without any manipulation. Therefore, it becomes an extremely useful power source for various electrical devices and appliances that require a stable DC power source.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of the power supply device of the present invention, FIGS. 2, 4, and 5 are circuit diagrams of device embodiments of the power supply device of the present invention, and FIG. 3 is a block diagram showing the basic configuration of the power supply device of the present invention. Waveform diagram for explaining the operation of the power supply device, Figure 6 fat, (b
1 and (C1 are circuit diagrams showing detailed modifications of the above embodiment, respectively. 11...... Transforming means, 12...
...... Rectifying means, VR1 (i = l - n
)... Constant voltage circuit, 13... Maximum voltage selection circuit, 14... Constant voltage circuit.

Claims (4)

[Claims] (1) Input the AC voltage V_1_a and
is an integer greater than or equal to 2) and the transformed output V_a_c_i (i=2~
rectifying means for rectifying each of these transformed outputs V_a_c_i to obtain n rectified outputs; inputting each of these rectified outputs to obtain a constant voltage V_S_T_i that is different from each other; (V_S_T_i_-_1<V_S
n constant voltage circuits VR_i that obtain _T_i); At each instant during each cycle of the transformed output V_a_c_i, the instantaneous value of each of the rectified outputs becomes the constant voltage V_S_T_i.
In the above constant voltage circuit VR_i, the constant voltage V_
A power supply device comprising: a maximum voltage selection circuit that outputs only from the circuit with the maximum S_T_i; (2) The power supply device according to claim 1, wherein each of the constant voltage circuits VR_i is a three-terminal constant voltage circuit. (3) A Zener diode is provided in the reference voltage setting section of the three-terminal constant voltage circuit forming the constant voltage circuit VR_i of the constant voltage V_i, and for each of the constant voltage circuits VR_2 to VR_a of the constant voltages V_2 to V_n, VR_2 is set from VR_a to VR_2.
3. The reference voltage according to claim 2, wherein each reference voltage is obtained by voltage division of a diode string connected in series between VR_a and the reference voltage setting section of VR_i so as to be in a forward direction. power supply. (4) The power supply device according to any one of claims 1 to 3, further comprising a final constant voltage circuit provided at the output section of the maximum voltage selection circuit.