JPS5822549A - Inverter unit for emergency power source - 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 The present invention relates to an emergency power inverter device.

FIG. 1 shows the load characteristics of the gas leak detection sensor. As shown in the diagram, this gas leak detection sensor consumes a large amount of power for preheating for 2 to 3 minutes immediately after the power is turned on, and when the temperature rises enough to complete preheating and enter the standby state, the power consumption automatically increases. is now suppressed. Such gas leak detection sensors normally operate on commercial AC power, but they also need to operate during a commercial AC power outage. An emergency power inverter device that can supply all the same voltages is required.

The emergency power inverter device for supplying power to the gas leak detection sensor described above must have a capacity that can cover the power consumption during preheating of the gas leak detection sensor, which increases cost and size. There was a problem.

On the other hand, if the capacity of the emergency power inverter device is made small enough to cover the standby power consumption of the gas leak detection sensor, it can be made cheaper and more compact.
There is a problem in that the drooping characteristic acts on the power consumption during preheating of the gas leak detection sensor, causing the output voltage to drop, causing the gas leak detection sensor to malfunction.

Therefore, an object of the present invention is to eliminate the voltage drop during inverter preheating, and to reduce the cost and size of an emergency power inverter device that supplies power to a load whose power consumption increases due to preheating for a certain period of time immediately after power is turned on. The purpose of the present invention is to provide an emergency power inverter device that can perform the following functions.

An embodiment of this invention is shown in FIG. That is, this emergency power inverter device is an emergency power inverter device that supplies power to a load whose power consumption increases during preheating. Constant voltage charging circuit CG
A storage battery BT that is constantly charged by this constant voltage charging circuit CG, a commercial power failure detection relay RY that detects a power outage of the commercial AC power source E, and a resonant capacitor C U, C3 are connected in parallel to a resonant winding N3. An inverter main body IN which uses a constant voltage transformer CVT as an output and operates by being supplied with power from the storage battery BT in response to a power failure detection operation of the commercial power failure detection relay RY to supply power to the load.
, a commercial frequency excitation signal (60Hz) for exciting the inverter main body IN in response to the power failure detection operation of the commercial power failure detection relay RY, and a high frequency excitation signal (80Hz) having a higher frequency than this commercial frequency excitation signal. and an inverter gate circuit IG that generates a power failure, and a timer in response to a power failure detection operation of the commercial power failure detection relay RY, and a timer that generates the high frequency signal before and after a timer time of 1 or more for preheating the load has elapsed. Switching and supplying the excitation signal and the commercial frequency excitation signal to the inverter main body IN, and matching the resonant frequency of the resonant winding N3 of the constant voltage transformer CVT and the resonant capacitors C and C2 with the excitation frequency of the inverter main body IN. A timer circuit TM that switches the capacitances of the resonant capacitors C and C3 before and after the timer time has elapsed, respectively.
It is equipped with

In this case, the inverter main body IN activates the thyristor SCR by a 60Hz commercial frequency excitation signal or a Fi80Hz high frequency excitation signal given from the inverter gate circuit IG.
By alternately conducting 5CR2Th, the primary winding N1 of the constant voltage transformer CVT is set to 60Hz or 80Hz.
At the same time, the resonant frequency of the resonant winding N3 of the constant voltage transformer CVT and the resonant capacitor C, C2 is set to 60
Hz or 80HzK switching, this constant voltage transformer C
60 Hz or 80 Hz from secondary winding N2 of vT
It is designed to take out a sine wave output of (The output voltage drops when the voltage is exceeded), and the output voltage-output current characteristic during high-frequency excitation has a drooping characteristic as shown by the broken line in Figure 3, and the output voltage begins to drop when the commercial frequency is excited. The value of the current increases, and when preheating the load, more power than the rated value, that is, a current more than the rated value, can be taken out without voltage drop. That is, in FIG. 3, even if the load preheating current Ip is extracted from the inverter main body IN, the output voltage of the inverter main body IN does not drop as in the conventional example. Note that even if a current exceeding the rated value is extracted from the inverter main body IN when preheating the load, no thermal problem will occur because the time required to preheat the load is short.

D ~ D4 is a diode, R is a resistor, C is a capacitor,
MCB ~MCB is a circuit breaker.

To explain in more detail, in this emergency power inverter device, when the commercial AC power supply E is turned on, the voltage of the commercial AC power supply E is stepped down by the transformer TR, and the voltage of the commercial AC power supply E is reduced by the bridge rectifier SI.
After being full-wave rectified at (6), it is applied to the electric circuit CG, and the storage battery BT is charged by the output current of this constant voltage charging circuit CG.

On the other hand, when the commercial AC power supply E is turned on, the commercial power failure detection relay RY is energized, the normally open contact ry1a is closed, and the normally closed contacts r'11b+r5' are closed. will be developed.

By closing the normally open contact ry1a, the relay RY for turning on the commercial power supply is energized, and the normally open contacts ry2a and ry21
．． is closed, the normally closed contact rY2c is opened, and the output terminal 10 is opened by closing the normally open contacts r)'2a and 'V2b.
．． 13, the voltage of the commercial AC power supply E appears and supplies power to the load.

After that, when the commercial AC power supply E has a power outage, the excitation of the commercial power failure detection relay RY stops, and the normally open contact ry□8 opens, and the normally closed contacts ry1b+ry□. is closed 1-1
The excitation of relay RY2 for commercial power output stops, and? #Open contact 'V2a' ry2b opens and normally closed contact ry2C closes, temporarily stopping power supply to the load. 〇Normally closed contact ry. By closing, the inverter closing relay RY3 is energized, the normally open contact ry3a is closed,
Power supply from the storage battery BT to the inverter main body IN and the inverter gate circuit IG is started. At the same time, power supply to the timer circuit TM is also started, and the timer circuit TM starts counting time. Timer time immediately after power outage of commercial AC power supply E (
Before the elapse of approximately 5 minutes, timer contacts tm□ and tm2 are on the NC side, an 80Hz high frequency excitation signal is supplied from the inverter gate circuit IG to the inverter main body IN, and timer contact tm3 is in an open state. Resonant capacitor C3 is disconnected and resonant winding II of constant voltage transformer CVT
! N3 and the resonant capacitor C0 resonate at 80Hz, and an 80Hz sine wave voltage appears at the output terminal of the inverter body IN. When this voltage becomes normal (the same voltage as the voltage of the commercial AC power supply E), the inverter output voltage Detection relay R
When Y4 is energized, the normally open contact ry4a is closed and the normally closed contact ry4b is opened, and the closing of the normally open contact ry4a energizes the inverter output input relay RY5, and the normally open contact ry5a*r3'5b is closed. At the same time, the normally closed contact ry5c opens too much. This normally open contact ry5a, r
When y5b is opened, an 80Hz sine wave voltage from the inverter body IN appears at the output terminal T between 12 and restarts supply t' to the load. When a power outage of the commercial AC power source E occurs after the preheating of the load by the commercial AC power source E is completed, only the steady current of the load is taken out from the inverter main body IN.
If a power outage occurs before the preheating of the load is completed, a large preheating current is extracted without dropping the voltage during the remaining preheating time of the load, and a steady current is extracted after the preheating is completed.

When the timer time of the timer circuit TM elapses and the timer circuit TM reaches a time-up state, the timer contacts tm and tm2 switch to the NO side, and a 60Hz commercial frequency excitation signal is supplied from the inverter gate circuit IG to the inverter main body IN, and the timer contacts jm3 is closed and the resonant capacitor C2 is connected, the resonant winding N3 of the constant voltage transformer CVT and the resonant capacitors C and C2 resonate at 60Hz, and a 60Hz sine wave voltage appears at the output end of the inverter body IN. 80
Constant power is supplied to the load instead of a Hz sine wave voltage.

When the power outage of the commercial AC power source E is restored, charging of the storage battery BT is restarted, and the commercial power outage detection relay RY1 is energized again, the normally open contact ry1a is closed, and the normally closed contact rylb l ryx is closed. is opened, the excitation of the inverter (9) input closing relay RY3 is stopped, and the normally open contact r
y3a opens, the power supply from the storage battery BT to the inverter main body IN and the inverter gate circuit IG stops, the output voltage of the inverter main body IN disappears, and the excitation of the inverter output voltage detection relay RY stops and the normally open contact ry
4a opens, the normally closed contact ry4b closes, the excitation of the inverter output turning relay RY5 stops, the normally open contact r)'5a l ry5b opens, and the normally closed contact ry5o closes, and the relay RY5 for inverter output is turned on. The power supply I stops. Immediately after this, the relay for turning on the commercial power supply output, RY, is energized,
The normally open contacts 'V2a,r)'2b close and the normally closed contacts ry,. is opened and the output terminal T.

The voltage of the commercial AC power supply E appears between 12 and 12.

Note that the normally closed contact ry2°+r'f5c performs an electrical interlock operation.

In this way, this embodiment generates a sine wave output of 80 Hz, which is higher than during normal operation, from the inverter main body IN using a constant voltage transformer CVT for a certain period of time after a power outage of the commercial AC power source E. (10) A current exceeding the rating can be taken out without dropping the voltage, and when preheating of the load is not completed due to an early power outage of the commercial AC power source E, the current exceeding the rating can be taken out from the inverter main body IN. Since the preheating of the load is continued, the rating of the inverter main body IN is made small enough to handle the steady current of the load, and the inverter main body IN? rEven if the size is reduced and the cost is reduced, a voltage drop during inverter preheating can be prevented, and the gas leak detection sensor will not malfunction.

As described above, the emergency power inverter device of the present invention is an emergency power inverter device that supplies power to a load whose power consumption increases during preheating, and includes a commercial AC power source that constantly supplies power to the load, and a commercial AC power source that constantly supplies power to the load. A charging circuit that is constantly supplied with power from an AC power supply, a storage battery that is constantly charged by this charging circuit,
a power outage detection circuit for detecting a power outage of the commercial AC power supply; and a constant voltage transformer in which a resonant capacitor is connected in parallel to a resonant winding;
an inverter main body that operates by supplying power from the storage battery and supplies power to the load in response to a power outage detected by the power outage detection circuit; an inverter excitation circuit that generates a commercial frequency excitation signal for exciting a power supply and a high frequency excitation signal having a higher frequency than the commercial frequency excitation signal; The high frequency excitation signal and the commercial frequency excitation signal are switched and supplied to the inverter main body before and after the timer time elapses, respectively, and the resonant winding of the constant voltage transformer and the resonant frequency of the resonant capacitor are changed to the inverter. The inverter is equipped with a timer circuit that switches the capacity of the resonant capacitor before and after the timer time has elapsed to match the excitation frequency of the inverter, so that the inverter's rating can cover the steady current of the load. This has the effect of being able to prevent a voltage drop during inverter preheating even though the inverter is made small enough to be small and the cost is reduced.

[Brief explanation of drawings]

FIG. 1 is a load characteristic diagram of a gas leak detection sensor, FIG. 2 is a circuit diagram of an emergency power inverter device according to an embodiment of the present invention, and FIG. 3 is an output voltage-output current characteristic diagram of the inverter. E/Commercial AC power supply, CG...constant voltage charging circuit, IN/
Inverter body, CVT/constant voltage transformer, CL. C3...Resonance capacitor, RY...Relay for commercial power failure detection, TM...Timer circuit, tm□~Lm3...Timer contact (13) Fig. 1 p □Output power connection Fig. 3

Claims (1)

[Claims] An emergency power inverter device that supplies power to a load whose power consumption increases during preheating, comprising: a commercial AC power source that constantly supplies power to the load; a charging circuit that is constantly supplied with power from the commercial AC power source; and a charging circuit that constantly charges the load. The storage battery and the commercial AC power supply stop! A power outage detection circuit that detects the entire power outage, and a constant voltage transformer having a resonant capacitor connected in parallel to a resonant winding as an output, are activated by being supplied with power from the storage battery in response to the power outage detection of the power outage detection circuit, and are applied to the load. an inverter body to which power is supplied; an inverter excitation circuit that generates a commercial frequency excitation signal for exciting the inverter body in response to power failure detection by the power failure detection circuit; and a high frequency excitation signal having a higher frequency than the commercial frequency excitation signal; , in response to a power outage detected by the power outage detection circuit, time is measured and the high frequency excitation signal and the commercial frequency excitation signal are switched and supplied to the inverter main body before and after a timer time equal to or longer than the preheating time of the load has elapsed, respectively. and a timer that switches the capacitance of the resonant capacitor before and after the timer time elapses, respectively, so that the resonant frequency of the resonant winding of the constant voltage transformer and the resonant frequency of the resonant capacitor match the excitation frequency of the inverter main body. An emergency power inverter device equipped with a circuit.