JP3800500B2 - Uninterruptible power system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an uninterruptible power supply device called a so-called UPS (Interruptable Power Supply) or SPS (Standby Power System), and in particular, automatically outputs an output timing of a signal for notifying a load device when the power supply is abnormal. The present invention relates to an improvement for controlling and thereby improving convenience as an uninterruptible power supply.
[0002]
[Prior art]
Conventionally, in this type of uninterruptible power supply, when the power supply connected to the input terminal goes out of power, the power stored in the battery or the like is supplied to the load device, and the power outage period becomes a predetermined set period. The load device is configured to notify that the power source is in a power failure state.
[0003]
As a result, the load device can perform a predetermined save process and end process while operating based on the electric power stored in the battery or the like.
[0004]
[Problems to be solved by the invention]
However, conventionally, in such an abnormal state notification of the power supply, the set period is assumed to be an environment where the voltage and frequency of commercial power such as a general home or office are relatively stable, and noise is generated in the environment. Since the instantaneous power outage caused by the above is from several ms to several tens of ms, it is generally set in the range of 20 to 30 ms.
[0005]
As a result, even if a personal computer with high power consumption and its peripheral devices are used in a general home or office, these devices can be safely terminated before power supply by a battery or the like is stopped in these devices. .
[0006]
However, when such an uninterruptible power supply is used in a computer or controller installed in a factory, the power supply noise due to large equipment is very large in the factory and the duration of the noise is several hundred ms. In many cases, it took up to several seconds. As a result, such a power supply noise notifies the load device that the power supply is in a power failure state, and the uninterruptible power supply cannot be installed in the factory as it is.
[0007]
Therefore, when such an uninterruptible power supply is used in a factory, each uninterruptible power supply is actually installed in the factory, and set up manually by the factory administrator or manufacturer's workers in that environment. Had to be changed, and if there were still problems, it was necessary to repeat further changes.
[0008]
Note that the later the notification timing is delayed, the later the saving process and termination process in the computer or controller based on the notification will be delayed. Can't just be set long.
[0009]
In recent years, depending on the type of uninterruptible power supply, devices that can set this setting period from a personal computer have been sold. However, such a general-purpose controller is also used in the above-mentioned factories. It is almost impossible to provide the setting software, and the setting must be changed manually.
[0010]
In the present invention, even in an environment where the voltage and frequency of commercial power, such as general homes and offices, are relatively stable, noise in a factory or the like is frequently superimposed and the voltage and frequency of commercial power are unstable. An uninterruptible power supply that can be suitably used regardless of the installation environment is obtained by outputting a signal notifying the abnormality of the power supply to the load device at an optimal timing even in an environment that is likely to become For the purpose.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the uninterruptible power supply of the present invention is an uninterruptible power supply that supplies power stored in a power storage member to a load device when a power supply connected to an input terminal fails. The detection means for detecting the duration of the power failure in the power source, and the elapsed time after the momentary power failure of the power source is detected is equal to or longer than a set period set according to the environment in which the power source is installed. Output means for outputting a signal notifying the power supply to the load device, and the set period is automatically lengthened when the detected maximum value or average value of the duration of the instantaneous power failure exceeds a predetermined value Setting means .
[0012]
By this configuration, first, the output means when automatically change the setting period according to the occurrence of the power failure in the power supply (duration), the power failure of the power supply is detected over a period of setting time Outputs a signal notifying the load device of the abnormality of the power source.
[0013]
Therefore, in an environment where the voltage and frequency of commercial power, such as general homes and offices, are relatively stable, a power supply abnormality is notified to the load device after the set period has elapsed, and In environments where noise is frequently superimposed and the voltage and frequency of commercial power tend to become unstable, it is possible to notify the load device of power supply abnormality after the set period has elapsed, It is possible to notify the load device of the abnormality of the power supply at the optimum timing according to the occurrence situation (duration) of the instantaneous power failure occurring in the power supply environment.
[0014]
In the uninterruptible power supply according to the present invention, the setting means selects one of a plurality of preset times as the setting period.
[0015]
If this configuration is adopted, the set period can be set with a simple process. In addition, since the plurality of times are set in advance by a manufacturer or the like that provides the uninterruptible power supply, naturally, considering the power supply capability of the power storage member and the power consumption of the load device, The set period can be selected from a time within a time range in which the load device can be reliably terminated before the supply power is insufficient, and the load device can be reliably terminated when the power supply is abnormal.
[0016]
The uninterruptible power supply according to the present invention calculates the standard deviation and the variance of the duration of the abnormal state of the power supply over a plurality of times instead of the setting means , and corresponds to three times the dispersion period than the standard deviation period. A time longer by the time is set as the setting period.
[0017]
By adopting this configuration, it is possible to set a time longer than the standard deviation period of the instantaneous power outage by a time corresponding to three times the dispersion period (so-called 3 sigma period) as a setting period, which is 97% or more. While preventing the output of the power failure notification signal in the event of an instantaneous power failure, the power failure notification signal can be output as soon as the instantaneous power failure period elapses at the time of the original power failure.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an uninterruptible power supply according to an embodiment of the present invention will be described with reference to the drawings.
[0019]
FIG. 1 is a system configuration diagram showing an example of a power supply system using the uninterruptible power supply according to Embodiment 1 of the present invention.
[0020]
The power supply system includes a load device 1 such as a home computer or an industrial sequencer, a commercial AC power source 2 that supplies power to the load device 1, and power between the commercial AC power source 2 and the load device 1. And an uninterruptible power supply 3 provided on the supply path.
[0021]
The uninterruptible power supply 3 mainly includes an input terminal 4 to which the commercial AC power supply 2 is connected, an output terminal 5 to which the load device 1 is connected, a two-input changeover switch 6 connected to the output terminal 5, Power during a power failure connected between the input terminal 4 and the bypass wiring 7 connected to one switching terminal 6a of the two-input selector switch 6 and the input terminal 4 and the other switching terminal 6b of the two-input selector switch 6 The input voltage and the input frequency of the commercial AC power input to the supply circuit 8 and the input terminal 4 are monitored, and when it is determined that a power failure has occurred based on this, the switching terminal of the two-input selector switch 6 is switched to one (6a ) To the other (6b) (detection means, setting means, output means) 9.
[0022]
The power supply circuit 8 at the time of a power failure is a two-input by converting a power storage member 10 composed of a capacitor or a battery capable of storing power and the power of the power storage member 10 into a voltage waveform similar to the rated voltage waveform of the commercial AC power supply 2. A DC / AC inverter 11 that outputs to the other switching terminal 6b of the changeover switch 6 and an AC / DC converter 12 that is connected to the input terminal 4 and charges the power storage member 10 with the power of the commercial AC power supply are provided.
[0023]
In this embodiment, the microcomputer 9 performs the following various processes in addition to the power supply source switching process at the time of the power failure.
[0024]
First, the microcomputer 9 sends a power failure signal to the load device 1 when the continuous power failure detection period determined based on the input voltage or input frequency of the commercial AC power exceeds a predetermined set time. Outputs a signal notifying the abnormality of the power supply. As a result, the load device 1 that is operating by using the power of the power storage member 10 of the uninterruptible power supply 3 due to a power failure can execute a predetermined evacuation process and termination process, and the state immediately before the power failure can be safely Can be held in. As a result, if the load device 1 is restarted after the end of the power failure, each process can be resumed from the state immediately before the power failure.
[0025]
Secondly, when a power failure occurs, the microcomputer 9 measures the power failure period, and performs the process of changing the set time based on this. The setting period changing process may be repeated, and may be performed every time a power outage occurs or every predetermined period.
[0026]
Specifically, the microcomputer 9 takes the maximum value or log of the power outage period and sets the maximum value or average value of the instantaneous power outage period determined based on this data if it exceeds 20-30 ms. Processing to change 20-30 ms set as the period to 5 s is performed.
[0027]
Instantaneous power outages that occur in environments where the voltage and frequency of commercial power, such as ordinary homes and offices, are relatively stable are generally within 20 to 30 ms, and noise from factories and the like is frequently superimposed for commercial use. Instantaneous power outages that occur in environments where the voltage and frequency of power tend to be unstable are generally within 5 s. The above two setting periods are selected based on these data. Therefore, even if the maximum value or average value of the instantaneous power failure period exceeds 5 s, the set period is set to 5 s.
[0028]
Next, the operation of the power supply system will be described.
[0029]
When the commercial power supplied from the commercial AC power supply 2 is stable, the microcomputer 9 of the uninterruptible power supply 3 sets the two-input selector switch 6 to one of the switching terminals 6a. The commercial power input to 4 is supplied to the output terminal 5 via the bypass wiring 7, and the load device 1 can continue to operate using this commercial power. Further, the power storage member 10 is charged with DC power supplied from the AC / DC converter 12 based on commercial AC power.
[0030]
In such a state, for example, when an abnormality occurs in the commercial AC power supply 2 and the AC commercial power is not normally supplied, the microcomputer 9 detects an input voltage abnormality or an input frequency abnormality, and the two-input changeover switch 6 A process of switching the switching terminal from one (6a) to the other (6b) is performed. Thereby, the power stored in the power storage member 10 is output from the DC / AC inverter 11, and this power is supplied from the output terminal 5 to the load device 1. Thereby, even if there is an abnormality in the commercial AC power supply 2, the load device 1 can execute the process under a stable power supply.
[0031]
Further, the microcomputer 9 outputs a power failure signal to the load device 1 when the power failure continuation detection period determined based on the input voltage and input frequency of the commercial AC power is equal to or longer than a predetermined set time. Thereby, the load apparatus 1 which is operating using the power of the power storage member 10 of the uninterruptible power supply 3 can execute a predetermined saving process and termination process, and the power of the power storage member 10 is insufficient. Before, it is possible to safely keep the state just before the power failure. Further, if the load device 1 is restarted after the end of the power failure, each process can be resumed from the state immediately before the power failure.
[0032]
Further, the microcomputer 9 measures the occurrence period of the power failure until the commercial AC power is determined to be normal, and the maximum value or average value of the instantaneous power failure period determined based on this data is 20 to 30 ms. If it exceeds, the process of changing 20 to 30 ms set as the setting period to 5 s is performed.
[0033]
As a result, the uninterruptible power supply 3 is, as shown by the relationship between FIGS. 2A and 2B, in an environment where the voltage and frequency of commercial power such as a general home or office are relatively stable, A power failure signal is output 20 to 30 ms after the detection of the power failure, and the computer connected as the load device 1 can be terminated before the power of the power storage member 10 is insufficient.
[0034]
In addition, in an environment where noise such as factories is frequently superimposed and the voltage and frequency of commercial power are likely to become unstable, as shown by the relationship between FIGS. A power failure signal is output after 5 s, and the sequencer connected as the load device 1 can be terminated before the power of the power storage member 10 is insufficient. Moreover, even if an instantaneous power outage over a period of several hundred ms occurs due to the above-mentioned noise etc., the power outage signal will not be accidentally output to the sequencer, so the system in the factory is inadvertently stopped frequently. It wo n’t happen.
[0035]
Particularly, since the microcomputer 9 incorporated in the uninterruptible power supply 3 automatically switches the setting period for determining the output timing of the power failure signal, a sequencer or the like is used as the load device 1. Even if it is used, the setting period can be changed without manual intervention. As a result, even when a large number of uninterruptible power supply devices 3 are installed in the factory, each setting period is automatically optimized, so that these processes are managed manually. The management cost of the entire system is not increased, and the reliability of the entire system can be improved.
[0036]
The above embodiment is a preferred embodiment of the present invention, but various modifications can be made without departing from the scope of the invention. For example, the setting process of the set period by the microcomputer 9 can also calculate the standard deviation and variance based on the log of the power outage period, and can be three times as long as the standard deviation period (so-called 3 sigma period). ) May be set so that a time longer than the time corresponding to () is set as the setting period. Setting such a setting period can prevent 97% or more of the erroneous output of the power failure signal resulting from the instantaneous power failure that occurs in the commercial power supply environment.
[0037]
Further, when the set period can be freely changed based on the instantaneous power failure log or the like in this way, the power supply capacity of the power storage member 10 and the power consumption of the load device 1 are taken into consideration. It is advisable to set an upper limit value for the set period so that predetermined saving processing and termination processing can be performed before the provided power becomes insufficient. Accordingly, the setting period can be freely optimized and set, and it can be ensured that the load device 1 is surely terminated before the power supplied to the power storage member 10 is insufficient.
[0038]
【The invention's effect】
In the present invention, even in an environment where the voltage and frequency of commercial power, such as general homes and offices, are relatively stable, noise in a factory or the like is frequently superimposed and the voltage and frequency of commercial power are unstable. Even in an environment that is likely to become, a signal notifying the load device of a power supply abnormality can be output at an optimal timing, and can be suitably used without selecting an installation environment.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing an example of a power supply system using an uninterruptible power supply according to Embodiment 1 of the present invention.
FIG. 2 is an explanatory diagram showing output timing switching of a power failure signal in the uninterruptible power supply according to Embodiment 1 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Load apparatus 2 Commercial AC power supply 3 Uninterruptible power supply 4 Input terminal 5 Output terminal 6 Two-input changeover switch 7 Bypass wiring 8 Power supply circuit 9 at the time of a power failure Microcomputer (detection means, setting means, output means)
10 power storage member 11 DC / AC inverter 12 AC / DC converter

Claims (3)

In the uninterruptible power supply that supplies the power stored in the power storage member to the load device when the power supply connected to the input terminal fails, the detection means for detecting the duration of the power failure in the power supply, and the instantaneous power supply Output means for outputting a signal notifying the load device of the abnormality of the power supply when the elapsed time after the detection of the power failure is equal to or longer than a set period set according to the environment where the power supply is installed And an uninterruptible power supply comprising: setting means for automatically extending the set period when the detected maximum value or average value of the duration of the instantaneous power failure exceeds a predetermined value .   The uninterruptible power supply according to claim 1, wherein the setting means selects one of a plurality of preset times as the setting period. In place of the setting unit, the standard deviation and variance of the duration of the abnormal state of the power supply over a plurality of times to calculate, only the longer time equivalent to three times the dispersion period than the standard deviation, the setting period The uninterruptible power supply according to claim 1, wherein

Images