JPS61161927A - Uninterruptible power equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an uninterruptible power supply device (
; It is related to.

[Technical background and problems of the invention]

Figure 3 is a block diagram showing an example of a conventional uninterruptible power IFI and device. In Figure 3, L is a commercial power supply and 2 is a diode! l! Fluid, 3 is inverter, 4
, an AC filter for improving the transform output waveform of the inverter 3, 5 a # battery, 6 a charger for charging the storage battery 5,
Reference numeral 7 denotes a storage battery-connected Nyristor suite in which C2 is turned on to continue power supply when the commercial power supply l is out of power.

However, in the configuration as shown in FIG.
This is not possible in the case of large-capacity equipment because it requires (therefore, there is a problem in economic efficiency 6).

Therefore, as another method, a configuration called a floating charging method as shown in FIG. 4 has been widely used. In FIG. 4, the same reference numerals as in FIG. 3 represent the same components. A rectifier 8 is composed of a thyristor and also serves as a charger for the storage battery 5. ! The firing angle α of the thyristor is changed by a control circuit (not shown) in order to control the output of the II current regulator 8 at constant voltage or constant current (from 2).
Charge state B of storage battery 5 (equipped with constant voltage charging or constant current charging function depending on the situation).

That is, in the configuration shown in FIG. 4, compared to the configuration shown in FIG. 3, there are fewer elements constituting the system because a dedicated charger and a storage battery connection sirisk switch are not required.

However, since the storage battery needs to be charged every few months at a voltage (equal voltage) that is about 10-15% higher than the normal charging voltage (floating voltage), the configuration C shown in Fig. 4; The rectifier 8 is connected to the lower limit voltage of the commercial power supply 1 (for example, the rated 9
0%), the input power factor will be As a result, the required manpower capacity of the rectifier 8 becomes larger than that of the configuration shown in Figure 3.Thus, although the configuration shown in Figure 4 has fewer elements, it is not necessarily economical. It cannot be said to be advantageous in that respect, and its scope of application is limited.
0. P2S5 ``Study of floating charging type uninterruptible power supply'' ) In recent years, office automation (OA) has rapidly become
As the progress is progressing, small-scale OA equipment such as personal computers is rapidly (= becoming popular), and with this, the demand for uninterruptible Ki source equipment for small-sized mold is also increasing. For zero-person equipment, the characteristics of the uninterruptible power supply required are as long as it has the same accuracy as a commercial power supply (for example, ±10% of the rating), and there is no problem in practical use. The necessary conditions are that it is functional and inexpensive.

The configurations shown in FIGS. 3 and 4 (2) and 5 (as described above) have problems in terms of economy, and are difficult to apply to small-sized uninterruptible power supplies as described above.

[Purpose of the invention]

X The purpose of the present invention is to solve the above-mentioned points.
An object of the present invention is to provide an uninterruptible power supply device consisting of a LiEm device, an inverter, and a sulfur sulfur reservoir, which has an inexpensive configuration and is equipped with the minimum required uninterruptible function. In order to achieve this object, the invention provides a bidirectional controllable converter between the output of the rectifier and the storage battery, which has a voltage control function and reverses the output current polarity.
K and discharge.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIG. *
In Figure 1, ■ is a commercial power supply, 21 is a rectifier made of diodes, 22 is an inverter with a constant pulse width, 0 is an AC filter that improves the output waveform of the inverter 22, the blades are storage batteries, and 25 is a voltage control function. and commercial electricity #l
It is a bidirectional controllable converter that reverses the output current polarity depending on the state (:

As a specific example of the bidirectional μ-factor pure converter 25, a configuration as shown in FIG. 2 can be used. In Figure 2, 2
50 is a diode, 251 is a transistor that performs on/off operation (chopper operation) using the DC output of the rectifier 21 as input, 253 is a transformer whose next input is the output t' of the AC filter, 252)! Changing the firing angle α of the thyristor using the secondary output of the transformer 253 ζ
This is a thyristor rectifier that can control the output voltage from two points.

Next, the operation of the embodiment shown in FIG. 1 will be explained. First, commercial IK
When the source l is normal, the DC output of the rectifier 21 is converted into AC m+2 by the inverter 22, and power is supplied to the load via the AC filter O. Since the pulse width of the inverter 22 is constant and the voltage control function does not wait, the output voltage accuracy of the inverter n is equal to the accuracy (2) of the local power supply l.As mentioned above, in the case of small-scale OA equipment, the commercial power supply value There is no practical problem with this accuracy, and the smoothing capacitor (not shown in Figure 1) normally installed at the input of the inverter 4 acts as a buffer against transient dips and surges in the commercial power supply 1. , cannot be transmitted to the load side.

The bidirectional controllable converter δ uses the output of the rectifier 21 as an input to charge the storage battery, and its output is controlled by a control circuit (not shown) to perform constant voltage charging or constant current charging depending on the state of charge of the storage battery 24. Take control. In the specific example of FIG. That is, while the transistor 251 is on, the output of the rectifier 21 is applied to the storage battery, and the charging voltage or charging current of the storage battery is controlled by changing the ratio of the on period to the off period. It is something to do.

Next (= commercial power supply l) When a power outage occurs, the power outage is detected by the detection circuit 1 (not shown), and a command to turn off the transistor 25LC shown in FIG.
A gate signal is given to From this, a voltage equal to the sum of the output of the rectifier 252 forming the bidirectional controllable converter δ and the storage voltage is applied to the inverter 22, and power supply continues without interruption. The voltage of the storage battery 24 decreases as it is discharged, but a rectifier 252 that receives the output of the current transformer filter circuit via a transformer 253 controls the output of the inverter 22 to be within the allowable voltage fluctuation range of the load by a control circuit (not shown). (This is the voltage accuracy of normal commercial power supply, about ±10%) (
In other words, the storage battery U is at a relatively high floating voltage or equal voltage just before discharge, so the output voltage of the rectifier 252 is kept low (ignition angle The progress of discharge (
1 to reduce the firing angle α of the unique rectifier 252.
:do. In this way, the voltage drop of the storage battery is corrected and the output voltage is controlled to be within the permissible range.

The fluctuation range of the voltage of the storage battery is approximately ±10 to ±15% even considering the fluctuation range from the floating charging voltage to the end of discharge voltage.For example, the permissible fluctuation range of the output voltage is ±10%.
Then, the voltage control range of the rectifier 252 is ±5%.
The capacity of the transformer 253 and rectifier 252 should be only 10% of the output rating.

In addition, the rating of the chopper circuit using the transistor 251 described above is such that the charging current of the storage battery 24 is normally 10% of the discharge region current.
%, the current rating may be about 10% compared to the device rating.

In this way, the bidirectional controllable converter 25 formed by the chopper circuit of the transistor 251C and the rectifier 252 can be used to charge the storage battery and to discharge the storage battery during a power outage (voltage drop due to two By doing this, it is possible to supply AC power that the load can tolerate without interruption.

In addition, as mentioned above, the capacity of the bidirectional controllable converter 5 can be quite small; , the structure can be small, simple, and inexpensive (the input power factor of the device is also 4th).
This is higher than the conventional device shown in the figure. ) The bidirectional controllable converter 5 of the embodiment shown in FIG.

The configuration is not limited to the configuration shown in FIG. For example, instead of the chopper circuit using the transistor 251C, a controlled rectifier may be used that uses a commercial power source as an input.

〔Effect of the invention〕

As explained above, according to the present invention, an uninterruptible power supply device consisting of a rectifier, an inverter, and a storage battery (:
It is recommended to install a bidirectional controllable converter between the output of the device and the storage battery (which has voltage control and reverses the output current polarity) to provide an inexpensive, minimally necessary uninterruptible function. A complete uninterruptible power supply can be configured.

[Brief explanation of drawings]

MT diagram is a block diagram showing one embodiment of the present invention, FIG. 882 is a block diagram showing the specific configuration of the bidirectional controllable converter in Embodiment 1 of FIG. FIG. 4 is a block diagram showing another example of the configuration of a conventional uninterruptible power supply (floating charging method). l... Commercial power supply 21... Rectifier 22...
・Inverter leg... Also flow filter 27 &...
-Storage battery 25...Bidirectional controllable converter 250...Diode 252...Thyristor IM flow device 253...Transformer. (7317) Agent Patent Attorney Noriyuki Chika (and 1 others)
Figure 1

Claims (2)

[Claims] (1) A rectifier that converts alternating current to direct current using commercial power as input, an inverter that converts the direct current output of the rectifier to alternating current,
The uninterruptible power supply device includes a storage battery that supplies DC power to the inverter during a power outage of the commercial power supply, having a voltage control function between the DC output of the rectifier and the storage battery,
and a bidirectional controllable converter capable of reversing the output current polarity is provided, and when the commercial power supply is normal, when the DC output of the rectifier is input, the storage battery is charged with the output of the bidirectional controllable converter, An uninterruptible power supply device characterized in that, during a power outage of the commercial power supply, a voltage equal to the sum of the output of the storage battery and the output of the bidirectional controllable converter is supplied to the inverter. (2) The bidirectional controllable converter includes a chopper circuit;
The uninterruptible power supply according to claim 1, characterized in that the uninterruptible power supply device is configured by connecting in antiparallel a thyristor rectifier which supplies the output of the inverter as an input via a transformer.