JPH06319236A - Electric power device - Google Patents

Abstract

PURPOSE:To provide an electric power device, in which the supply of power to load is not stopped to transiently generated overload. CONSTITUTION:In an electric power device jointly having a function converting the power of an AC input power supply 10 into power by a power translating equipment and supplying load with electricity and a function capable of changing over power to power from a battery 15 and continuously supplying load with electricity at the time of the abnormality of the AC input power supply 10, a changeover means 17 alternately changing over feed to feed from the battery 15 and feed from the AC input power supply 10 periodically at the time of the normalcy of the AC input power supply 10 and a storage means 16, in which the transient output fluctuation of the electric power device at the time of the changeover is stored successively, are provided. A comparison means 18 comparing the allowable value of transient output fluctuation and transient output fluctuation stored in the storage means 16 and a display alarm means 19 displaying the result of the comparison means 18 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device such as an uninterruptible power supply device for high reliability power supply.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a power supply device for high reliability power supply of this type converts AC power from an AC input power supply 10 into DC power by a rectifier 11 and uses an inverter 12 as a converter. The AC power is converted into AC power again, and stable AC power is supplied to the load 14 via the switch 13.

Storage battery 1 when AC power is lost due to power failure
Similarly, the DC power from 5 is converted into AC power by the inverter 12 and the power supply to the load 14 is continued to be uninterrupted.

FIG. 4 shows the load 1 in the power supply device of FIG.
4 shows the state of supply of electric power to No. 4. Generally, the power from the AC input power source 10 is supplied to the load 14 by the A route, but as described above, when the AC power fails, it is switched to the B route and the power from the storage battery 15 is used. There is no power outage.

The C route from the standby power supply 22 is for continuing the power supply to the load 14 without any interruption when an abnormality occurs in the A route. When the power route is switched, the output voltage of the power supply device fluctuates transiently. This is the rectifier 11
Is generated due to the difference between the output voltage of the battery and the voltage of the storage battery 15, the difference in impedance between the two power sources, and the like.

Generally, the loads 14 to be connected are so-called non-linear loads in which the fluctuation amount of the load current is not proportional to the fluctuation amount of the load voltage due to the nature of the load.

Most of the loads are calculators, which are intentionally increased or replenished. Most of the power supplies anticipate an increase in load in the future, so the capacity of the power supply has a sufficient margin with respect to the load capacity at the beginning of delivery, but the conventional power supply has little overload margin for nonlinearity. ,
As described above, a transient overload occurs at the time of switching the power feeding route of the electric power due to increase or change of the load. In general, a power supply device has a waveform storage circuit 16 that stores the states before and after the failure at several points other than the output of the power supply device in preparation for the failure.

[0008]

As described above, when the load 14 is non-linear, the load current changes due to the transient output voltage fluctuation that occurs when the power route is switched, that is, the so-called load voltage fluctuation. The transient overload occurs in the conventional power supply device because it changes several times. Most of the loads 14 are intentionally increased or replenished, and due to the increased capacity, a transient overload occurs within the allowable amount of the power supply device and within the allowable transient fluctuation. If a power failure occurs in this state, a transient overload occurs at the time of switching to the storage battery operation, the power supply device is subjected to protection stop, and power supply to the load 14 is stopped.

Generally, the load 14 constitutes a small capacity unit group, so that the capacity gradually increases. Therefore, although the capacity increase (load fluctuation) in small capacity units does not reach the level at which a transient overload occurs, the power feeding route from the A route to the B route at the time of the power failure mentioned above. This is because the change amount becomes maximum when all the loads at that time undergo a transitional change in the output voltage when switching to the negative mode. The same can be said when switching to the C route. In this case, the power is supplied from the C route for maintenance and inspection, and then the power is returned to the A route power supply.

When switching to the A route, the load changes most since it changes from no load to full load as seen from the power supply device. As described above, in the case of a non-linear load, a transient overload will occur even if the load capacity is within the allowable range of the power supply.Therefore, the transient fluctuation of the output voltage of the power supply also exceeds the allowable value. The protection function of the side causes it to go down.

When the capacity of the load 14 is increased stepwise, an overload condition within the overload detection level may occur above the rated capacity of the power supply, although it is within the allowable range of the power supply. The above-mentioned problem occurs because the switching to the switch is not performed.

If the maintenance inspection is completed and there is no abnormality, the worst case of load reduction will occur. As described above, the conventional power supply device has the drawback that the power supply device stops the power supply due to the nature of the load 14.
Further, as described above, in a state where there is no abnormality in maintenance inspection or the like, there is also a drawback that the trigger for reducing the load is unknowingly pulled. An object of the present invention is to provide a power supply device in which the power supply to the load 14 is not stopped even when a transient overload occurs.

[0013]

In order to achieve the above-mentioned object, a power supply device of the present invention has a function of converting the electric power of an AC input power supply by a power conversion device to supply power to a load, and a function of the AC input power supply. In a power supply device that also has a function of switching to electric power from a storage battery in the event of an abnormality and continuously supplying power to the load, in the normal operation of the AC input power supply, power supply from the storage battery and power supply from the AC input power supply are performed periodically. Switching means for alternately switching to, the storage means for sequentially storing the transient output fluctuation of the power supply device at the time of switching, the allowable value of the transient output fluctuation, and the transient value stored in the storage means. The comparison means for comparing the output fluctuation and the display warning means for displaying the result of the comparison means are provided.

In order to achieve the above object, the power supply device of the present invention has a function of converting the power of the AC input power supply by the power converter to supply the power to the load, and from the storage battery when the AC input power supply is abnormal. In a power supply device having both a function of switching to the electric power of 2 to continuously supply power to the load and a switching function of supplying power from the standby power supply to the load, the AC input power supply and the standby power supply are periodically switched. Means and means for sequentially storing transient output fluctuations of the power supply unit at the time of switching are provided so that preventive maintenance can be performed by using accumulated storage data for maintenance and inspection.

[0015]

As shown in FIG. 4, the rectifier 11 is stopped and electric power is supplied from the B route while the electric power is being supplied to the load 14 by the A route. When the transient fluctuation of the power supply output at this time is memorized and compared with the allowable value and also compared with the accumulated data, the load increase ratio exceeds an abnormally high case or exceeds the allowable value. Will be displayed and warned and announced to prevent any further increase in load. Also, preventive maintenance is achieved by the same function as described above when switching between A-route and C-route.

The accumulated data can be used to determine the load state such as the load increasing tendency or the load connection with different characteristics on the display screen of the power supply device, and the preliminary check can be performed before starting the maintenance inspection. Therefore, it is possible to prevent the occurrence of overload without knowing. From these A routes to B routes
Switching between the A route and the C route is automatically and regularly performed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment of the present invention shown in FIG.
Reference numeral 7 is an automatic switching circuit, 18 is a comparator 19 and a display warning circuit, and constitutes a unit 20. Since the other circuit configurations have the same functions as those in FIG. 4, the same numbers are given and the description thereof is omitted.

In FIG. 1, the rectifier 11 is stopped by the automatic switching device 17 while the AC input power source 10 is supplying power to the load 14 by the A route, and the power is supplied from the B route. The changes in the output voltage and the output current of the power supply device at the time of this switching are stored in the waveform storage circuit 16. The fluctuation amount is compared with the allowable value by the comparator 18, and also compared with the data accumulated as described above. If the increase ratio of the load 14 exceeds the abnormally high case or the allowable value, the power source is changed. An announcement is given on the display screen of the device to prevent further increase in load, and a warning is given to the outside.

The above-described operation of checking the load condition is carried out periodically to trend the history of the load 14.
When returning from the B route to the A route, the same operation as described above is performed, and the same applies when switching from the A route to the C route and from the C route to the A route. It works.

FIG. 2 shows another embodiment of the present invention. Since the regulator 21 for varying the output of the power supply device is provided and the other circuit components have the same functions as those in FIG. 1, the description thereof will be omitted.

While power is being supplied to the load 14 by the A route or B route, the controller 21 is operated to cause the output fluctuation of the power supply device and the output fluctuation at that time is stored in the waveform storage circuit 16. Subsequent processing can obtain the same effect according to the above-described embodiment of the present invention.

According to the present invention, a transient change is applied to a load to check its characteristics, and an announcement is made in advance for an increase in the load or a load connection having a different characteristic so that the power supply does not become overloaded. The load power feeding stop is preventively maintained, and the effect of the present invention can be brought about even if the output of the power supply device is forcibly changed as described above.

[0023]

When the AC power is lost during a power failure, the power supply device has a role of switching to the DC power from the storage battery and continuously supplying the power to the load. In addition, it also has a function of switching to the standby power supply and continuously supplying power to the load in case of an abnormality of the power supply device or maintenance and inspection thereof.

During these switching operations, the output of the power supply device fluctuates transiently. The type of load connected to the power supply unit is unspecified (there are few cases where the nature of the load is clear)
It is generally increased or re-released in.
In particular, in the case where a non-linear load is increased by a non-linear load or due to a release, an overload occurs due to the transient output fluctuation of the power supply unit at the time of switching as described above, and the power supply to the load is continued. There was a situation where the conventional power supply unit stopped.

The power supply unit is required to have a higher reliability in order to continuously supply electric power to the load, but according to the present invention, the following effects can be obtained. (1) Since the characteristics of the load are successively grasped by automatically switching the power supply route to the load on a regular basis, it is possible to make an announcement before the overload.

(2) Since the state of the load can be checked from the accumulated data even during maintenance and inspection, preventive maintenance processing can be taken before starting inspection. (3) A power supply device with higher reliability can be provided by easily attaching the unit of the present invention to a conventional power supply device.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing another embodiment of the present invention.

FIG. 3 is a block diagram of a conventional power supply device.

FIG. 4 is a flowchart showing the functions of the power supply device shown in FIG. 3 in terms of power flow.

[Explanation of symbols]

10 ... AC input power supply 11
… Rectifier 12… Inverter 13
… Switcher 14… Load 15
Storage battery 16 Waveform storage circuit 17
... Automatic switching circuit 18 ... Comparator 19
Display warning circuit 20 Unit 21
… Regulator 22… Standby power supply 23
… Power supply

Claims (2)

[Claims] 1. A function of converting the power of an AC input power supply to a load by converting the power of the AC input power supply, and a function of switching to the power from a storage battery to continuously supply power to the load when the AC input power supply is abnormal. In a power supply device having both of: a switching means for periodically switching between the power supply from the storage battery and the power supply from the AC input power supply when the AC input power supply is normal, and a transient of the power supply device at the time of switching. Storage means for sequentially storing various output fluctuations, a comparison means for comparing the allowable value of the transient output fluctuations with the transient output fluctuations stored in the storage means, and a result of the comparison means is displayed. A power supply device having display warning means. 2. A function of converting the electric power of an AC input power source by a power conversion device to supply power to a load, and a function of switching to electric power from a storage battery to continuously supply power to the load when the AC input power source is abnormal. And in the power supply device that also has a switching function that can supply power from the standby power supply to the load,
Means for periodically switching the AC input power supply and standby power supply, means for sequentially storing transient output fluctuations of the power supply device at the time of switching, and accumulated memory data are used for maintenance and inspection. A power supply device characterized by enabling preventive maintenance.