KR890005150Y1 - Power circuit for transfor ac-ac - Google Patents

Abstract

None.

Description

Uninterruptible Power Supply for AC-AC Converter

Fig. 1 (a) is a circuit diagram of the device of the present invention, and Fig. 1 (b) is a detailed wiring diagram of the inverter (3) contact point of Fig. 1 (a).

2 is a block diagram of a conventional apparatus.

* Explanation of symbols for main parts of the drawings

1: rectifier 2: storage battery

3: inverter 4: filter

5: solenoid coil 6: transformer

10-12: Load Drive Relay

The present invention relates to an uninterruptible power supply for an AC-AC converter, and more particularly, to an uninterruptible power supply suitable for a load that is low power and does not require accurate sine wave and constant voltage.

Conventionally, as shown in FIG. 2, between the rectifier 52 and the filter 53 for converting a commercial AC input 51 into a DC, a storage battery A for power supply in case of power failure is connected, and the filter 53 There is an uninterruptible power supply which is configured to connect to the waveform distortion prevention filter 55 through an inverter 54 composed of an SCR or an output transistor, and to connect the output of the filter 55 to a necessary AC load. Looking at it, the common AC input 51 is changed to DC as the rectifier 52 and then smoothed as the filter 53. The smoothed voltage is changed to the AC voltage of the sine wave frequency and the constant voltage as the inverter 54 through the filter 55. It is sent to the AC output, the filter 55 to prevent the waveform distortion of the AC output.

At the same time, the side battery A is charged by the direct current output from the rectifier 52.

In the case of power failure, power is supplied to the inverter 54 to charge the battery A to obtain a normal AC output. However, such an inverter 54 uses a SCR or an output transistor to control the firing angle so that a constant voltage is obtained. Since a constant frequency is obtained, a control device in the inverter 54 becomes very complicated and its price is very high. Therefore, the control device in the inverter 54 is usually used only for precision equipment.

The present invention is to configure the inverter using an elastic piece, a solenoid and a transformer in order to solve the conventional disadvantages, but because it is a device having a priority in the case of power failure by giving a power supply priority in case of power failure to the connected load, it is a small capacity, sine wave And to supply AC power only to loads that do not require constant voltage, the configuration is simple and the manufacturing cost is low. In particular, the purpose of the present invention is to provide an uninterruptible power supply for an AC-AC converter that can reduce the size of the device by minimizing the power consumption of the capacitor. As will be described below with reference to the accompanying drawings, the configuration, operation and effect of the present invention.

Referring to FIG. 1, a constitution of the present invention is an uninterruptible power supply including a rectifier, a capacitor, an inverter, and a filter. The anode of the capacitor 2 has one side of the solenoid coil 5 and a secondary winding of the transformer 6. It is connected to the center point, the negative electrode of the battery (2) is connected to the movable contact (C) interlocked with the solenoid coil (5), the spring touch contact (K) in contact with the lower side of the movable contact (C) is the inverter drive command A fixed point point (a, b) connected to the other side of the solenoid (5) via a contact (7a) of the relay (7) and a contact (8b ₁ ) of the commercial AC power confirmation relay (8). ) Are connected to both ends of the primary winding of the transformer 6, respectively, and the loads (L _1- L ₃ ) at both ends of the output of the inverter 3 and the filter 4 having AC ends of the secondary winding of the transformer 6 as AC outputs. ) and switches (SW ₁ -SW _3), respectively, but the connection to the jikryeok, the load (L ₁ -L ₃₎ are respectively connected to a relay (31-33) in parallel and switches (SW ₂ , SW ₃ is the load terminal 9 and the positive electrode of the storage battery 2 connected through the contacts 10b ₁ , 10b ₂ , 11b ₁ of the load driving relays 10, 11 to the power terminal B of the priority encoder PR. ⁺ ) And distribution resistors (r _1- r ₃ ), inverter drive command relays (7) and load drive relays (10, 11, 12) at one end, and distribution resistors (r ₁ -r ₃ ) are respectively used for commercial AC power. Of the priority encoder PR through the contacts 8b ₂ , 8b ₃ , 8b ₄ of the confirmation relay 8 and the contacts 31a, 32a, 33a of the relays 31-33 and the buffers I _1- I ₃ . It is connected to the inputs (D ₇ -D ₅ ), respectively. The common output (GS) of the priority encoder (PR) is connected to the base of the emitter grounded transistor (Tr ₁ ), but the collector of the transistor (Tr ₁ ) drives the inverter. The outputs Q ₀ -Q ₂ of the priority encoder PR, which are connected to the other end of the command relay 7, are respectively emitter-grounded transistors Tr ₂ -Tr ₄ through AND gates G ₁ -G ₃ . To the base of the transistor, but the collectors of transistors (Tr ₂ -Tr ₄ ) Including the priority load detector 14 connected to the other end of the load driving relay (10, 11, 12), explaining the effect of this configuration of the present invention, when a commercial AC power is normally applied to the first (a AC power is supplied to the load stage 9 via the line S indicated by the dotted line in FIG.

At this time, the commercial AC power confirmation relay 8 is excited and the normally closed contacts 8b ₁ , 8b ₂ , 8b ₃ , 8b _{4 of the} commercial AC power confirmation relay 8 are opened to open the solenoid coil 5 of the inverter 3. ) Is cut off from the battery 2 and at the same time the inputs D ₁ -D ₅ of the priority encoder PR of the priority load detector 14 are cut off, so that the priority load detector 14 does not operate.

At this time, as in the prior art, the commercial AC power is changed to direct current through the rectifier 1 to charge the storage battery 2.

In addition, the lower part (9) has a normally closed contact _{(10b 1, 10b 2),} (11b 1) the user and the load (L ₁ -L ₃₎ desired by a load driving relays (10, 11) switches (SW ₁ - SW ₃ ) to drive.

Therefore, AC power is supplied only to the load selected by the switches (SW _{1 to} SW ₃ ).

That is, when commercial AC power is input, power is supplied to and disconnected from the load by turning on and off the load selection switches SW _{1 to} SW _{3 in a} normal state.

In this state, when the AC power used is out of power, the commercial AC power confirmation relay 8 is closed and the normally closed contacts 8b ₁ , 8b ₂ , 8b ₃ and 8b ₄ are closed.

In addition, when any one of the switches SW ₁ -SW ₃ is turned on or all of the switches SW ₁ -SW ₃ are turned on, the power supply of the battery 2 is input to the preferred encoder PR through the buffers I ₁ -I ₃ (D ₇ -D _5). Is applied.

As shown in the following table, the output GS of the priority encoder PR becomes high when power (high) is input to any of the inputs (D ₇ -D ₅ ) to drive the inverter drive command relay (7). The transistor Tr ₁ is turned on to allow the inverter 3 to operate.

Here, the operation state of the inverter 3 will be described with reference to FIG. 1 (b). At first, that is, when the inverter drive command relay 7 is turned off, the movable contact C matches the spring touch point K. FIG. In this state, when the inverter driving command relay 7 is excited in this state, the power of the battery 2 is applied to the solenoid coil 5, so that the movable contact C is attracted to the solenoid coil 5 to the fixed contact b. Contact.

In this state, the movable contact C is separated from the spring finger contact K, and at the same time, the battery 2 is connected to the primary winding of the transformer 6 to induce a predetermined voltage in the secondary winding.

However, since the movable contact (C) is separated from the spring tangent contact (K), the power supply of the battery to the solenoid coil (5) is cut off, and the movable contact (C) is restored by its own elastic force and the spring force of the spring tangent contact (K). While pressing, contact with the fixed contact (a).

In this state, the power supply of the storage battery 2 is applied again to the primary winding of the transformer 6, but at this time, the movable contact C is connected to the fixed contact b, and the Power is applied.

In this state, since the movable contact (C) is in contact with the spring contact point (K), the magnetization force of the solenoid (5) and the spring force of the spring touch point (K) are moved back to the fixed contact point (b), whereby the fixed contact point ( 6) contact with

As this condition is repeated, the transformer 6 cannot obtain an accurate constant frequency due to the induction of an alternating voltage in the secondary winding, the elastic force of the movable contact point C, the spring force of the spring contact point K, and the like. You can get it.

In addition, the operation of the load stage 9 and the priority load detector 14 is the priority of the priority load detector 14 once any one of the loads L _1- L ₃ is selected by the switches SW _1- SW ₃ . The outputs Q ₀ -Q ₂ of the encoder PR selectively drive the load driving relays 10, 11, 12 as shown in Table 1 below.

TABLE 1

As can be seen from Table 1, when the load (L ₁ ) is selected as the switch (SW ₁ ), the load driving relays (10, 11, 12) are excited and the contacts (10b ₁ , 10b ₂ , 11b ₁ ) are opened. The switch (SW ₂ , SW ₃ ) is on and the power supply is cut off, even if other loads (L ₂ , L ₃ ) are selected.

In addition, the only AC power switch (SW ₂₎ is turned on when selecting a load (L _2), the above similarly load driving relay 11 are woman is to cut off the power of the load (L _2), the load (L ₂₎ Supplied.

If all of the switches SW ₁ -SW ₃ are turned off, the inverter driving command relay 7 is deactivated, and thus the operation of the inverter 3 is stopped.

As described above, according to the present invention, it is possible to supply AC power in the case of power failure as a simple structure, and in particular, to supply AC power according to priority only to an important load, thereby reducing the current consumption of the battery and miniaturizing the device. In addition, it can provide a low-cost uninterruptible power supply.

Claims (1)

In an uninterruptible power supply including a rectifier, a capacitor, an inverter and a filter, the positive electrode of the battery 2 is connected to the center of the winding side of the solenoid coil 5 and the primary side of the transformer 6, the negative electrode of the battery 2 Is connected to the movable contact (C) interlocked with the solenoid coil (5), and the spring-only contact (K) in contact with the lower side of the movable contact (S) is commercially available with the contact (7a) of the inverter drive command relay (7). It is connected to the other side of the solenoid 5 through the contact 8b ₁ of the AC power confirmation relay 8, and the fixed contacts a and b corresponding to the movable contact C are connected to both ends of the primary winding of the transformer 6. The loads (L _1- L ₃ ) and the switches (SW ₁ -SW ₃ ) are connected in series between the outputs of the inverter 3 and the filter 4, which are connected to each other, and both ends of the secondary winding of the transformer 6 are AC outputs. but each connected to a load (L ₁ -L _3), the contact of each connecting a relay (31-33) in parallel, switches (SW _2, SW ₃₎ is a load driving relays (10, 11) _{(10b 1, 10b 2, 11b} 1) the power supply terminal (B ⁺⁾ and the distribution resistance (r ₁ -r ₃₎ of the positive electrode is a priority encoder (PR) of the connection portion being at the bottom (9), a battery (2) through It is connected to one end of the inverter drive command relay 7 and the load drive relay 10-12, and the distribution resistors r _{1 to} r ₃ are respectively the contacts 8b ₂ , 8b ₃ , 8b of the commercial AC power confirmation relay 8. ₄ ) is connected to the inputs (D ₇ -D ₅ ) of the priority encoder (PR) via the contacts 31a, 32a, 33a and the buffers I _1- I ₃ of the relays 31-33, respectively. the common output of the (PR) (GS) is, but connected to the base of an emitter grounded flange requester (Tr _1), the collector of the transistor (Tr ₁₎ is connected to the other terminal of the inverter drive command relay (7), and a priority encoder ( The outputs Q ₀ -Q ₂ of PR are connected to the base of the emitter grounded transistors Tr ₂ -Tr ₄ through AND gates G ₁ -G _3, respectively, but transistors Tr ₂ -Tr ₄ Collector is connected to the other end of the load drive relays (10, 11, 12) The AC-AC converter for UPS hayeoseo including granted priority load detector 14.