JPH09327175A - Rectifying circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the measures against high frequency noise from electronic equipment without increasing their sizes, which can be used for AC input voltage of wither 100V or 200V system such as personal computers. SOLUTION: In a rectifying circuit which can be connected to an AC input power source of 100V and 200V, reactors 3a and 3b are connected for reducing higher harmonic components of an incoming current from the AC input power source 1, and a transfer switch 4 is provided for connecting the reactors 3a and 3b in parallel during the connection to the 100V AC input voltage source 1 and also in series during the connection to the 200V AC input voltage source 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rectifier circuit that can be commonly used for both 100 V and 200 V input AC voltage sources, and particularly to efficiently suppress harmonic current in a power source section of a personal computer or the like. The present invention relates to a rectifier circuit suitable for

[0002]

2. Description of the Related Art In electronic devices such as personal computers, for example, "Electrical Cooperation Research Vol. 46, No. 2, Harmonics in Electric Power Systems and Countermeasures ... As described in "Technical Committee" (published in June, 1990), high-frequency noise (high-frequency current) mixed in the input AC voltage source increases waveform distortion of the power system and failure of power equipment.

Regarding such harmonic noise, in 1994, the Agency for Natural Resources and Energy issued the "Guideline for Harmonic Suppression of Home Appliances / General-Purpose Products", and the target level for the harmonic suppression for electric / electronic equipment was specified. Is shown in. The technique for achieving this target level is described in detail in the above-mentioned "Electrical Cooperation Research Vol. 46 No. 2". In particular, on page 151, a circuit diagram in which a reactor is inserted is described as a harmonic suppression technique, together with data before and after suppression of harmonics of a personal computer (personal computer). A harmonic suppression circuit using this reactor is sufficiently practical, and it is extremely easy to realize a power supply device for electronic equipment incorporating this circuit.

However, in this technique, the precondition is that the commercial input voltage is fixed. Commercial power supplies in the world are roughly divided into 100V system (Japan, US, etc.) and 2
There are 00V systems (Europe, England, etc.). In many small and portable electronic devices, the power supply is designed so that it can be used in various parts of the world by switching the switch or even without switching, but regarding the circuit that suppresses harmonics using a reactor, However, if consideration is given so that the same configuration can be used in various parts of the world, inconvenience occurs.

That is, when a reactor is designed for a 200V system and is used for a 100V system, an inflow current becomes large, and there is a risk that the reactor may overheat. Also, if the reactor is optimally designed for 100V system, 200V
When used in a system, the applied voltage to the reactor becomes excessive and the harmonic suppression function deteriorates. Also, 100V system and 2
If the reactor is designed so that there is no problem in any of the 00V system, the reactor has an excessive size, which is significantly disadvantageous in the size of the device and the production cost. Therefore, in the conventional reactor insertion technology, it is necessary to separately design the 100V system and the 200V system.

[0006]

The problem to be solved by the prior art is that in the prior art, circuits for inserting a reactor to suppress the harmonics of the input AC voltage source are 100V and 200V.
When shared with the system, the reactor cannot be downsized. The object of the present invention is to solve these problems of the prior art and to solve the problems of 100 V and 200 V for personal computers and the like.
It is an object of the present invention to provide a rectifier circuit that can be used as a high-frequency noise countermeasure for an electronic device that can be used as an input AC voltage source for both systems without increasing the size of the device.

[0007]

In order to achieve the above object, the rectifier circuit of the present invention is a rectifier circuit which can be used in the input AC voltage source 1 of both 100V system and 200V system. First connected to the AC voltage source 1 to reduce the harmonic component of the inflow current from the input AC voltage source 1,
When the second reactors 3a and 3b are connected to the 100V-system input AC voltage source 1, the first and second reactors 3a and 3a,
3b is connected in parallel, and when connected to the input AC voltage source 1 of 200V system, the reactor configuration switching means (switch 4) for connecting the first and second reactors 3a and 3b in series.
And characterized in that:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the connection of two reactors is switched in series or in parallel in accordance with the input voltage, whereby the domestic standard of harmonic current (input voltage: 1
00V) and international standard (IEC standard, input voltage: 230
It corresponds to both V). That is, the rectifier circuit is switched to a configuration of a voltage doubler rectifier circuit when connected to an input AC voltage source of 100 V system, and to a configuration of a bridge rectifier circuit when connected to an input AC voltage source of 200 V system,
It can be shared by both 100V system and 200V system, and the reactor for suppressing the harmonic current of the input AC voltage source is divided into two, and these reactors are
When connected to a V system input AC voltage source, in parallel, 2
When connected to a 00V input AC voltage source, they are connected in series. In this way, by switching the connection of the two reactors in both the 100V system / 200V system, it is possible to suppress the harmonic current of the input AC voltage source of both systems with the same reactor insertion circuit configuration. You can

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a circuit diagram showing one embodiment of the configuration of the rectifier circuit of the present invention according to the present invention. In FIG. 1, 1
Is an input AC voltage source of 100V system or 200V system, 2
Is a bridge rectifier, 3a and 3b are reactors according to the present invention, 4 is a changeover switch as the reactor configuration changing means of the present invention, and 5a and 5b are capacitors.

The input AC voltage source 1 has one end connected to the bridge rectifier 2 and the other end connected to the reactors 3a and 3b. Smoothing capacitors 5a and 5b are connected in series between the + pole and the − pole of the bridge rectifier 2, and the reactor 3
a and 3b are also connected in series. In this embodiment,
Reactors 3a and 3b are made of the same iron core. Then, the other end of the rectifying bridge 2 and the reactors 3a and 3b
The middle point of the series connection of and the middle point of the series connection of the smoothing capacitors 5a and 5b are connected via the changeover switch 4.

The changeover switch 4 has two transfer contacts, and the respective contacts are interlocked. FIG.
1A shows a connection state by the changeover switch 4 when the input AC voltage source 1 is 100V, and FIG. 1B shows a connection state by the changeover switch 4 when the input AC voltage source 1 is 200V. There is. The connection configuration of the rectifying bridge 2 with the change-over switch 4, the reactors 3a and 3b, and the smoothing capacitors 5a and 5b will be described with reference to FIGS.

FIG. 2 is a circuit diagram of the rectifier circuit of FIG.
It is a circuit diagram which shows the example of a connection with respect to the input alternating voltage source of a system. As shown in FIG. 2, the input AC voltage source 1 is AC10.
If it is 0 V, the changeover switch 4 in FIG. 1 is used to connect the reactors 3a and 3b in parallel, and the midpoint of the smoothing capacitors 5a and 5b connected in series is input through the reactors 3a and 3b connected in parallel. Connect to voltage source 1.

FIG. 3 is a circuit diagram of the rectifier circuit of FIG.
It is a circuit diagram which shows the example of a connection with respect to the input alternating voltage source of a system. As shown in FIG. 3, the input AC voltage source 1 is AC20.
If it is 0V, the reactors 3a and 3b are connected in series, and the reactors 3a and 3b are connected to the AC input terminal of the rectifying bridge 2. The configurations shown in FIGS. 2 and 3, respectively, are a voltage doubler rectifier circuit for a 100 V system, and
It is a bridge rectification circuit for the 00V system, and its configuration and switching are the same except for the connection of the reactors 3a and 3b.
This is a conventional general technique.

As described above with reference to FIGS. 1 to 3, in the rectifier circuit of this embodiment, the reactor for reducing the harmonic component of the inflow current of the input AC voltage source is divided into two reactors. 3a and 3b are connected in parallel at 100V input and in series at 200V input so that the harmonic current ratios at 100V and 200V are the same. Further, the series connection and the parallel connection of the reactors are switched by the changeover switch 4 in association with the switching of the voltage doubler rectifier circuit and the bridge rectifier circuit of the conventional rectifier circuit. As a result, 100V / 200V switching, which was wasteful in the conventional reactor insertion technology, can be made compact without waste.
It can be made lightweight.

The present invention is not limited to the embodiments described with reference to FIGS. 1 to 3, and various modifications can be made without departing from the scope of the invention. For example, although the reactors 3a and 3b are not formed of the same iron core in this embodiment, they may be formed of the same iron core. Further, by controlling the switching operation of the changeover switch 4 by combining the input voltage detection circuit and the drive circuit, that is, by interlocking with the switching operation of the voltage doubler rectifier circuit and the bridge rectifier circuit as the prior art, It is also possible to automatically switch the reactor connection configuration.

[0016]

According to the present invention, a high frequency noise countermeasure for an electronic device, such as a personal computer, which can be used with any input AC voltage source of 100V system or 200V system, is provided without increasing the size of the device. It is possible to achieve.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a configuration of a rectifier circuit of the present invention according to the present invention.

FIG. 2 is a circuit diagram showing an example of connection of the rectifier circuit in FIG. 1 to an input AC voltage source of 100V system.

3 is a circuit diagram showing an example of connection of the rectifier circuit in FIG. 1 to a 200V-system input AC voltage source.

[Explanation of symbols]

1: Input AC voltage source, 2: Bridge rectifier, 3a, 3
b: reactor, 4: switch, 5a, 5b: smoothing capacitor.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yukio Aoyama 1 Ikegami, Haruoka-cho, Owariasahi-shi, Aichi Hitachi Asahi Electronics Co., Ltd.

Claims (1)

[Claims] 1. A rectifier circuit that can be used in both input AC voltage sources of 100 V system and 200 V system, and is connected to the input AC voltage source, and a harmonic component of an inflow current from the input AC voltage source. When connecting the first and second reactors for reducing the noise and the 100V-system input AC voltage source, the first and second reactors are connected in parallel,
When connected to a 0V input AC voltage source, the above first and second
And a reactor configuration switching means for connecting the reactors in series with each other in series.