KR100926968B1 - Automatic voltage regulator - Google Patents

Abstract

PURPOSE: An automatic voltage regulator is provided to optimally stabilize an output voltage by maintaining a rapid response and high output voltage stability. CONSTITUTION: A plurality of taps is formed in a primary side and a secondary side of a main transformer(TR3). A first compensating transformer(TR1) supplies a compensating voltage to the primary side of the main transformer. A second compensating transformer(TR2) supplies a compensating voltage to an output terminal(Vout). A first switching part(110) has a plurality of switching devices corresponding to the taps of the primary side of the main transformer. A second switching part(120) has a plurality of switching devices corresponding to the taps of the secondary side of the main transformer. A control part(130) generates a control signal for operating the switching device of the first switching part and the second switching part in order to maintain an output voltage detected in the output terminal within tolerance range of regulation voltage stability.

Description

Automatic voltage regulator

The present invention relates to an automatic voltage regulator, and more particularly, to an automatic voltage regulator that simplifies the configuration by direct connection and optimally stabilizes the output voltage with fast response and high output voltage stability. .

In general, the voltage applied to the load of the consumer generally remains higher than the rated voltage as the voltage is supplied higher than the specified voltage in consideration of the voltage drop caused by the line constant of the transmission and distribution system.

However, in densely populated areas and industrial complexes where a large amount of electricity is consumed, the voltage applied to the load of the consumer remains lower than the rated voltage during the day when the electricity is consumed. At night time when the electricity consumption is relatively low, the voltage supplied to the load is kept higher than the rated voltage.

In this case, the electrical and electronic device as a load causes the malfunction of the device due to low voltage or, on the contrary, not only shortens the insulation and life of the device due to overvoltage but also increases the power consumption in proportion to the voltage. There is a problem.

As such, an automatic voltage regulator is installed to more stably supply the unstable voltage due to the transmission and load characteristics to the load to maintain efficient operation and reliable operation.

Specifically, in the automatic voltage regulator of Patent No. 501486, as shown in FIG. 1, the input stage Vin (H₁, N₁), compensation transformer 10, TR₁, proportional transformer 20, TR2, and proportional transformer tap switch unit ( 40c, 40d), main transformer 30, TR₃, control unit 60b, and output terminals Vout (H₂, N₂) to detect output voltage fluctuated by variations in input voltage or output load, Set the output voltage to within the allowable range.

For this purpose, the power is applied to the input terminal Vin (H₁, N₁) and is proportional to the one end 15 and the middle end 16 of the primary side of the main transformer 30, TR₃ that supplies the output terminal Vout (H₂, N₂). The transformers 20 and TR2 are connected to each other, and a constant voltage (for example, 110V) is supplied from the main transformers 30 and TR3 to organically generate a tap voltage determined by a combination of windings of both taps.

In addition, the proportional transformer tap switching parts 40c and 40d on both sides formed of an anti-parallel constituent thyristor module (SCR Module), which is a power semiconductor switching element, are connected to one side tap of the proportional transformer 20 (TR2) and the joint connection part 70. In a state in which a plurality of dogs are connected in one-to-one relationship between one side end and the other side end end of the proportional transformer 20 (TR2) and the other side end of the joint connector 70, the output voltage detected at the output terminal Vout in the controller 60b is defined. Receives a control signal generated to maintain the allowable range and induces induced voltage by the tap connected in one-to-one connection with the joint connection part 70 determined by the combination of the one tap and the other tap to be induced in the proportional transformer 20 (TR2). do.

Here, the proportional transformer tap switching unit 40c constituted by four (X4) anti-parallel constituent thyristor modules (SCR module) each has a side end (ⓐ) of the proportional transformer taps (①, ②, ③, ④) and the joint connection unit 70. , Ⓑ, ⓒ, ⓓ, and the transformer tap switch 40d are respectively between the proportional transformer taps ⑤, ⑥, ⑦, ⑧ and the other ends (ⓔ, ⓕ, ⓖ, ⓗ) of the joint connection 70. One-to-one connection, one tap of the one tap switching unit 40c and one tap of the other tap switching unit 40d are energized to the joint connection unit 70 by operation signals G40c and G40d of the control unit 60b. Induce the combined induced voltage to the compensation transformer (10, TRk) by (20, TR2).

The secondary sides 17 and 18 of the main transformer 30 and TR₃ are connected to the output terminals Vout (H2, N2) and the output voltage detection terminal (⑩, ⑪) of the control unit 60b to change the output voltage. When the detection is out of the specified voltage allowable range, the gate operation (ON) signals G40c and G40d are applied to the thyristor module (SCR Module) of the tap switching sections 40c and 40d, which are already determined and required, so that they are energized. The voltage V9-11 is induced on the secondary side of the compensation transformer 10 (TR₁) by a combination of tap voltages determined by the winding of the proportional transformer 20 (TR2) tap, and the primary of the compensation transformer 10, TR10. The primary voltage (V14-16 = Vin-V12-13) of the main transformer 30, TR₃ as the compensation voltage (V12-13 = N1 ÷ N2 x V9-11) to the primary side by the winding ratio of the side and the secondary side. ), And the output voltage (Vout = V17-18 = N4 ÷ N3 × V14-16) is stabilized within the specified value by the primary side voltage (V14-16) of the compensated regulated main transformer (30, TR₃). .

However, in the conventional automatic voltage regulator, the thyristor module of the transformer tap switching sections 40c and 40d is sequentially operated in order to stabilize the output voltage fluctuated by the change of the input voltage or the load within a specified voltage allowable range, thereby stabilizing the output voltage. There was a problem that the response speed is delayed.

In other words, when the voltage tolerance is set to 220V rating and the input voltage ± 15% and the output voltage stability is ± 2% (± 4.4V), the switching element of the high voltage tap when controlling the boost or step-down by 8 signals by the combination And low tap switching elements are sequentially combined, and zero crossing is performed every 1/2 cycle (8.33 ㎳) so as not to generate a surge voltage. For example, as shown in FIG. When the output voltage suddenly changes from V to 253V, ⑧-②, ⑧-③, ⑧-④, ⑦-①, ⑦-②, and ⑦- sequentially from ⑧-① by the control signal generated from the controller 60b. ③, ⑦-④, ⑥-①, ⑥-②, ⑥-③, ⑥-④, ⑤-①, ⑤-②, ⑤-③, ⑤-④ The speed is delayed.

This delay in response speed is, for example, in an information processing device such as a computer, when the voltage drop of about 10 to 20% is continued for 0.025 to 0.03 seconds, the operation is stopped, such as a variable speed motor controller using a semiconductor element. In powered equipment, the motor will stop after a voltage drop of more than 20% continues for 0.05 to 0.03 seconds or more, even if an electronic switch is used on the power supply side. In addition, lighting equipment such as a luminaire having a lighting circuit is sensitive to the effect of the instantaneous voltage drop. In particular, the high-voltage discharge lamp has a problem that the voltage drop of about 20 to 30% is turned off after 0.05 to 1 second. It is necessary to prevent the response speed from delaying.

Furthermore, in order to keep the output voltage stability within ± 1%, the control unit 60b of the automatic voltage regulator includes eight thyristors (SCR modules) of the proportional transformer tap switching units 40c and 40d on each side (X8). The total number of control signals should be 16.

In this case, the output voltage stability of 2.2V, which is ± 1%, can be maintained, but since it crosses up to 250µs by zero crossing every 1/2 cycle (8.33µs), the output voltage stabilization response speed is doubled than that of ± 2%. .

From this, in order to prevent the output voltage stabilization response speed from being extremely delayed, two automatic voltage regulators are connected in series, and for example, the compensation voltage induced at both ends of the compensation transformer T₁ is applied in the case of the front end. 33V with ± 2% output voltage stability and 16.5V with ± 1% output voltage stability in the latter stage can be implemented to achieve voltage stability of ± 1% while maintaining the output voltage stabilization response speed. Two automatic voltage regulators are required, resulting in power consumption, instability, and manufacturing costs.

The present invention is to solve the above problems, the configuration is simplified to increase the efficiency and reduce the manufacturing cost, while maintaining the output voltage stability accurately within the range of ± 1%, and output voltage in a quick response by direct connection The purpose is to provide an automatic voltage regulator that immediately stabilizes the voltage.

In order to achieve the above object, the present invention comprises: a main transformer for forming a plurality of tabs on the primary side and the secondary side, transforming the power applied to the input stage and supplying the output stage to the output stage; A primary side is connected to one end of the input side and the primary transformer primary side, and one end and the other end of the secondary side are connected to an intermediate tab and one of the plurality of tabs of the primary transformer primary side, and the main transformer A first compensation transformer for supplying a compensation voltage to the primary side; A primary side is connected to one end and an output end of the secondary side of the main transformer, and one end and the other end of the secondary side are connected to an intermediate tab and one of the plurality of tabs of the main transformer secondary side, and compensated to the output end side. A second compensation transformer for supplying a voltage; A switching element corresponding to a plurality of taps of the primary transformer primary side, respectively, having one end connected in common to the other end of the secondary side of the first compensation transformer, and the other end connected to the plurality of taps of the primary side of the main transformer respectively; A first switching unit to make; A switching element corresponding to the plurality of taps of the secondary side of the main transformer, respectively, having one end connected to the other end of the second side of the second compensation transformer, and the other end connected to the plurality of taps of the secondary side of the main transformer, respectively. A second switching unit to make; And detecting an output voltage at the output terminal, and generating a control signal to operate the corresponding switching elements of the first switching unit and the second switching unit in two steps so that the detected output voltage is maintained within a specified voltage stability tolerance range. And a control unit, wherein the corresponding switching element of the first switching unit is operated by a control signal generated according to an output voltage first detected among the control signals generated in two steps by the control unit. The corresponding switching element of the second switching unit is operated by a control signal generated by supplying the compensation voltage to the primary side of the main transformer and then generating a compensation voltage according to the detection voltage of the secondary side of the main transformer supplied with the first compensation voltage. While generating a second compensation voltage from the second compensation transformer and supplying it to the output terminal, Also it provides an automatic voltage regulator, comprising a step of maintaining within the allowable range.

Preferably, nine taps are formed on the primary side of the main transformer, three taps are formed on the secondary side, and the first switching unit is formed of nine taps respectively corresponding to nine taps of the primary transformer primary side. A switching element of an anti-parallel configuration thyristor module (SCR Module), and a switching element of three anti-parallel configuration thyristor modules (SCR Module) respectively corresponding to the three taps of the secondary side of the main transformer It can be done.

According to the automatic voltage regulator of the present invention having the above-described configuration, when operating the proportional transformer tap switch in a sequential tap-change method at zero crossing so as not to generate a surge voltage, the output voltage stability is increased by increasing the number of taps. By increasing the output voltage stability by combining them in series without increasing the number of taps or the number of taps, the response speed of stabilization of output voltage is very delayed, the efficiency is lowered, and the manufacturing cost is increased. It can be applied to ultra-precision loads or instruments by maintaining the accurate response within the stability range within ± 1% while stabilizing the output voltage immediately even when the voltage fluctuates between the lowest voltage and the highest voltage, which is the control range of boost and step-down, while reducing costs. It will work.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, which are intended to be described in detail so that those skilled in the art can easily implement the present invention. It is not intended that the technical spirit and scope of this invention be limited.

2A to 2C are diagrams illustrating an automatic voltage regulator for maintaining an output voltage stability within a range of 1% according to an exemplary embodiment of the present invention, and a process of adjusting voltage of step-up or step-down for this purpose.

As shown in FIG. 2A, the automatic voltage regulator 100 according to the embodiment of the present invention includes an input terminal Vin, a main transformer TR₃, a first compensation transformer TR ′, a first switching unit 110, 2 is made up of the compensation transformer TR2, the second switching unit 120, the control unit 130 and the output terminal Vout.

The main transformer TR3 transforms a power applied to the input terminal Vin and supplies it to the output terminal Vout, and forms a plurality of tabs on the primary side and the secondary side. In an embodiment of the present invention, nine tabs are formed on the primary side, and the other ends of the switching elements 111 to 119 of the first switching unit 110 corresponding to each tab are respectively connected, and three tabs are formed on the secondary side. Tabs are formed and connected to the other ends of the switching elements 121 to 123 of the second switching unit 120 corresponding to each tab, respectively.

The first compensation transformer TR 변압기 may have a primary side connected to one end of an input terminal Vin and the primary side of the main transformer TR₃ so as to receive a first compensation voltage for boosting or stepping down to the primary side of the main transformer TR₃. Supply.

To this end, the secondary side of the first compensation transformer TR 변압기 may be connected to one end and the other end of the main tab of the main transformer TR₃ by connecting one end and the other end to one of the plurality of taps on the primary side of the main transformer TR₃. The voltage is supplied from the side.

The other end of the second side of the first compensation transformer TR ′ is commonly connected to one end of the switching elements 111 to 119 of the first switching unit 110.

The first switching unit 110 corresponds to a plurality of taps on the primary side of the main transformer TR₃, for example, a first switching element of an anti-parallel configuration thyristor module (SCR Module) that is, for example, nine power semiconductor switching elements. 111 to 119, respectively, and one end of the first switching elements 111 to 119 is commonly connected to the other end of the second side of the first compensation transformer TR ′, and the primary side of the main transformer TR₃. With the other end connected to a plurality of tabs, respectively, zero crossing such that only one tab of the plurality of taps of the primary side of the main transformer TR₃ is connected to the other end of the second side of the first compensation transformer TR 변압기. In the crossing, only the corresponding switching element is operated.

The second compensation transformer TR2 has a primary side connected to one end of the secondary side of the main transformer TR₃ and an output terminal Vout, and supplies a second compensation voltage for boosting or stepping down to the output terminal Vout.

To this end, the secondary side of the second compensation transformer TR2 is connected to one end and the other end of the plurality of tabs of the secondary side of the main transformer TR₃ by connecting one end and the other end to the secondary of the main transformer TR₃. The voltage is supplied from the side.

The other end of the second side of the second compensation transformer TR2 is commonly connected to one end of the second switching elements 121 to 123 of the second switching unit 120.

The second switching unit 110 corresponds to a plurality of taps on the secondary side of the main transformer TR₃, for example, a second switching element of an anti-parallel configuration thyristor module (SCR Module), which is three power semiconductor switching elements. 121 to 123, respectively, and one end of the second switching elements 121 to 123 is commonly connected to the other end of the second side of the second compensation transformer TR₂, and the second side of the main transformer TR₃. With the other end connected to a plurality of tabs, zero crossing is made so as to connect only one tab of the plurality of taps of the secondary side of the main transformer TR₃ to the second end of the second compensation transformer TR₂. In the crossing, only the corresponding switching element is operated.

The control unit 130 detects an output voltage at the output terminal Vout, and the first switching unit 110 and the second switching unit 120 in two stages so that the detected output voltage is maintained within a specified voltage stability tolerance range. A control signal is generated to operate the corresponding switching element.

Of the control signals generated in two stages in the control unit 130, as shown in Figure 2b, the primary side of the main transformer (TR₃) by the first stage of the control signal generated according to the output voltage detected first Corresponding switching elements 111-1 of the first switching unit 110 to connect the corresponding tab on the primary side of the main transformer TR₃ to the other end of the secondary side of the first compensating transformer TR₁ for step-up or step-down. By controlling the operation of any one of 119, the corresponding switching element of the first switching unit 110 operates to generate a first compensation voltage in the first compensation transformer (TR₁) to the primary side of the main transformer (TR₃) To feed.

In addition, as shown in FIG. 2C of the control signals generated in two steps by the control unit 130, two generated according to the secondary side detection voltage of the main transformer TR₃ receiving the first compensation voltage. The second switching unit may be configured to connect the corresponding tap of the secondary side of the main transformer TR₃ to the other end of the secondary side of the second compensating transformer TR₂ for the step-up or step-down of the output terminal Vout by the control signal of the step ( By controlling one of the corresponding switching elements 121 to 123 of 120 to operate, the corresponding switching element of the second switching unit 110 operates to generate a second compensation voltage in the second compensation transformer TR2. And supply to the output terminal Vout to finally control the output voltage to remain within the specified voltage stability tolerance.

With reference to the accompanying drawings the operation of the step-up or step-down according to the change in the input voltage or load of the automatic voltage regulator 100 according to an embodiment of the present invention having the above configuration will be described in detail as follows.

3A to 3D show an example of adjusting a voltage within the output voltage stability 2% rated range in the automatic voltage regulator of FIG. 2A, and FIGS. 4A to 4D are rated at 2% of the output voltage stability in the automatic voltage regulator of FIG. 2A. An example of adjusting a voltage higher than the range is shown, and FIGS. 5A to 5D show an example of adjusting a voltage lower than a 2% rated range of output voltage stability in the automatic voltage regulator of FIG. 2.

In the embodiment of the present invention, the input voltage rating is 220V, and the output voltage stability is maintained within ± 1% in two stages. In the first stage, the turn ratio of the first compensation transformer TR₁ is 1: 3.4375 (32V: 110V) to adjust the step-up or step-down within the range of 184 ~ 256V while changing up and down up to 32V at 8V interval when the rated range is 216 ~ 224V.The voltage difference between the taps on the primary side of the main transformer (TR₃) Nine are formed while keeping the same and connected to any one of the nine taps by the operation of the first switching element, and the output stage voltage is stepped up or down so as to remain within the range of ± 2% on the primary side of the main transformer TR₃, In step 2, the winding ratio of the second compensation transformer TR2 is set to 1: 16.7 (3V: 50V), and the voltage is increased or decreased within the range of 219 to 221V while changing up to 3V at 3V intervals when the rated range is 216 to 224V. Adjusting coercion For example, forming three while keeping the voltage difference between the taps on the secondary side of the main transformer TR₃ equal to each other, and being connected to any one of the three taps by the operation of the second switching element, being maintained within a range of ± 2%. The secondary voltage of the main transformer (TR₃) shall be stepped up or down so as to remain within ± 1% of the output terminal Vout.

First, an example in which the automatic voltage regulator 100 adjusts a voltage within a 2% rated range of output voltage stability will be described with reference to FIGS. 3A to 3D.

In the automatic voltage regulator 100 according to the embodiment of the present invention, first, as shown in FIGS. 2B and 3A, the output voltage variation of the output terminal Vout detected by the controller 130 is 216 to 224 V, resulting in voltage stability. When within the rated range of 2%, the gate operation (ON) of the thyristor module that is the corresponding switching element 115 is maintained so as to maintain the rated range among the nine switching elements 111 to 119 of the first switching unit 110 at zero crossing. A second signal on the secondary side of the first compensation transformer TR₁ is connected to a fifth intermediate tap on the primary side of the main transformer TR₃, and the first compensation transformer By maintaining the voltage on the secondary side of TR ', the primary voltage of the main transformer TR3 is maintained at 216 to 224 V.

Next, as shown in FIGS. 2C and 3B to 3D, the main transformer TR₃ secondary output voltage detected by the controller 130 is in the range of 216 to 224 V, thereby maintaining voltage stability within 1%. In order to satisfy this, as shown in FIG. 3C, the corresponding switching element 122 is one of the three switching elements 121 to 123 of the second switching unit 120 at zero crossing. A control signal is generated to operate by immediately applying a gate operation signal to a thyristor module so that the other end of the secondary side of the second compensation transformer TR₂ is connected to the middle tap of the secondary side of the main transformer TR₃. The output terminal Vout voltage is maintained at 219 to 221 V by preventing the voltage from being induced at the secondary side of the second compensation transformer TR2.

However, when the secondary output voltage detected by the control unit 130 is 216 to 218 V and thus voltage stability of less than 1% cannot be maintained, as shown in FIG. 3B, the zero crossing is performed. A control signal is generated by immediately applying a gate operation signal (ON) to a thyristor module which is the second switching element 121 among the three switching elements 121 to 123 of the second switching unit 120 to operate. The voltage induced in the first tap 10 connected to the corresponding second switching element 121 operating with the secondary side intermediate tap 11 of TR₃ is induced on the secondary side of the second compensation transformer TR₂. As the second compensation voltage of 3V is induced through the first side of the second compensation transformer TR2, the final output voltage is directly stepped up to 219 to 221V to stabilize the output voltage within 1%.

In addition, even when the output voltage of the main transformer (TR₃) secondary side detected by the controller 130 is 222 to 224 V, voltage stability of less than 1% cannot be maintained, as shown in FIG. Of the three switching elements 121 to 123 of the second switching unit 120, a gate operation (ON) signal is immediately applied to the thyristor module which is the corresponding second switching element 123 to generate a control signal to operate the main transformer ( Voltage induced in the third tap 12 connected to the corresponding second switching element 123 operating with the secondary side intermediate tap 11 of TR₃) is induced on the secondary side of the second compensation transformer TR₂, As the second compensation voltage of -3V is induced through the first side of the second compensation transformer TR2, the final output voltage is directly stepped down to 219 to 222V to stabilize the output voltage within 1%.

Meanwhile, an example in which the automatic voltage regulator 100 adjusts the voltage higher than the rated range of 2% of the output voltage stability will be described with reference to FIGS. 4A to 4D.

In the automatic voltage regulator 100 according to the embodiment of the present invention, first, as shown in FIGS. 2B and 4A, first, an output voltage variation of the output terminal Vout detected by the controller 130 is higher than 224V so that voltage stability 2 If outside the rated range of%, the thyristor module which is the corresponding switching element of the switching elements 116 to 119 to step down as necessary among the nine switching elements 111 to 119 of the first switching unit 110 at zero crossing. A control signal is generated to operate by immediately applying a ON signal to the gate operation, so that the voltage induced in the corresponding tap connected to the corresponding switching element operating with the fifth intermediate tap of the primary side of the main transformer TR₃ is applied to the first voltage. It is induced on the secondary side of the compensating transformer TR 'and directly adjusts the voltage of the primary side of the main transformer TR₃ to 216 to 224 V within a 2% range through the primary side of the first compensating transformer TR'.

Specifically, when the output voltage is higher than 224V, the output voltage stability is divided into 8V intervals in the range of ± 2%, and at 224 to 232V, the control element 130 of the switching element 116 to the first switching unit 110 at 224 to 232V. By operating the sixth switching element 116 of 119, the voltage induced in the fifth intermediate tap and the sixth tap of the primary side of the main transformer TR₃ is induced on the secondary side of the first compensation transformer TR '. 8V is applied to the primary side of the main transformer TR₃ to be stepped down through the primary side of the first compensation transformer TR₁, thereby rapidly stabilizing to 216 to 224V within a 2% range.

Similarly, at 232 to 240V, the control unit 130 operates the seventh switching element 117 of the switching elements 116 to 119 of the first switching unit 110 to operate the first compensation transformer TR₁. 16V is pushed down to the primary side of the main transformer TR₃ through the side, and at 240 to 248V, the control unit 130 is the eighth switching element of the switching elements 116 to 119 of the first switching unit 110. 118 is operated to apply the main transformer TR₃ to the primary side such that 24V is stepped down through the primary side of the first compensation transformer TR₁, and the control unit 130 controls the first voltage at 248 to 256V. The 9th switching element 119 of the switching elements 116 to 119 of the switching unit 110 is operated so that 32 V is stepped down through the primary side of the first compensation transformer TR₁. On the side.

As shown in FIGS. 2C and 4B to 4D, since the output voltage of the secondary side of the main transformer TR₃ detected by the controller 130 is in the range of 216 to 224 V, in FIGS. 2C and 3B to 3D. As described, keep it at a voltage stability within 1% of 219 ~ 221V.

Next, an example in which the automatic voltage regulator 100 adjusts a voltage lower than a rated range of 2% of the output voltage stability will be described with reference to FIGS. 5A to 5D.

In the automatic voltage regulator 100 according to the embodiment of the present invention, as shown in FIGS. 2B and 5A, first, an output voltage variation of the output terminal Vout detected by the controller 130 is lower than 216V, resulting in voltage stability 2. If it is out of the rated range of%, the thyristor module, which is the corresponding switching element of the switching elements 111 to 114, is stepped up so as to boost as necessary among the nine switching elements 111 to 119 of the first switching unit 110 at zero crossing. A control signal is generated to operate by immediately applying a gate operation signal (ON), so that the voltage induced in the corresponding tap connected to the corresponding switching element operating with the fifth intermediate tap of the primary side of the main transformer TR₃ compensates for the first compensation. It is induced on the secondary side of the transformer TR 'and directly boosts the voltage of the primary side of the main transformer TR₃ to 216 to 224 V within a 2% range through the primary side of the first compensation transformer TR'.

Specifically, when the output voltage is lower than 216V, the output voltage stability is divided into 8V intervals in a range of ± 2%. At 216 to 208V, the control unit 130 switches the switching elements 111 to 111 of the first switching unit 110. By operating the fourth switching element 114 of 114, the voltage induced on the fifth intermediate tap and the fourth tap of the primary side of the main transformer TR3 is induced on the secondary side of the first compensation transformer TR '. The voltage is rapidly stabilized to 216 to 224 V within a 2% range while being applied to the primary side of the main transformer TR₃ so that 8V is boosted through the first side of the first compensation transformer TR '.

Similarly, at 208 to 200 V, the control unit 130 operates the third switching element 113 of the switching elements 111 to 114 of the first switching unit 110 to operate the first compensation transformer TR₁. The main transformer TR₃ is applied to the primary side such that 16V is boosted through the side, and at 200 to 192V, the control unit 130 is the second switching element among the switching elements 111 to 114 of the first switching unit 110. Operation 112 is applied to the primary side of the main transformer TR₃ so that 24V is boosted through the primary side of the first compensation transformer TR ', and the controller 130 switches the first switch at 192 to 184V. By operating the first switching element 111 of the switching elements 111 to 114 of the unit 110, the primary side of the main transformer TR₃ so that 32V is boosted through the first side of the first compensation transformer TR₁. Will be added to.

Next, as shown in FIGS. 2C and 5B to 5D, since the output voltage of the secondary side of the main transformer TR₃ detected by the controller 130 is in a range of 216 to 224 V, the above FIGS. 2C and 3B to 3D. As described in above, keep it at a voltage stability within 1% of 219 ~ 221V.

This invention is not limited to the above embodiments, various modifications are possible within the scope of the invention described in the claims, and such modifications are also included within the scope of the invention.

Figures 1a and 1b is a table showing an example of a conventional sequential tap-changing automatic voltage regulator and a switching device operating in the corresponding voltage range for voltage regulation of the boost or step,

2A to 2C are diagrams illustrating an automatic voltage regulator for maintaining an output voltage stability within a range of 1% according to an embodiment of the present invention, and a process of adjusting voltage of step-up or step-down for this purpose.

3A to 3D illustrate an example of adjusting a voltage within a 2% rated range of output voltage stability in the automatic voltage regulator of FIG. 2A.

4A to 4D illustrate an example of adjusting a voltage higher than a 2% rated range of output voltage stability in the automatic voltage regulator of FIG. 2A,

5A to 5D illustrate an example of adjusting a voltage lower than a 2% rated range of output voltage stability in the automatic voltage regulator of FIG. 2.

<Description of the symbols for the main parts of the drawings>

10: first compensation transformer (TR₁) 20: proportional transformer (TR₂)

30: main transformer (TR₃) 40c, 40d: proportional transformer tap switching unit

60b: control part 70: joint connection part

100: automatic voltage regulator according to an embodiment of the present invention

110: first switching unit 111 to 119: first switching element

120: second switching unit 121 to 123: second switching element

130: control unit TR ': first compensation transformer

TR₂: Second compensation transformer TR₃: Main transformer

Claims (2)

A main transformer for forming a plurality of tabs on the primary side and the secondary side, transforming power applied to the input stage, and supplying the power to the output stage; A primary side is connected to one end of the input side and the primary transformer primary side, and one end and the other end of the secondary side are connected to an intermediate tab and one of the plurality of tabs of the primary transformer primary side, and the main transformer A first compensation transformer for supplying a compensation voltage to the primary side; A primary side is connected to one end and an output end of the secondary side of the main transformer, and one end and the other end of the secondary side are connected to an intermediate tab and one of the plurality of tabs of the main transformer secondary side, and compensated to the output end side. A second compensation transformer for supplying a voltage; A switching element corresponding to a plurality of taps of the primary transformer primary side, respectively, having one end connected in common to the other end of the secondary side of the first compensation transformer, and the other end connected to the plurality of taps of the primary side of the main transformer respectively; A first switching unit to make; A switching element corresponding to the plurality of taps of the secondary side of the main transformer, respectively, having one end connected to the other end of the second side of the second compensation transformer, and the other end connected to the plurality of taps of the secondary side of the main transformer, respectively. A second switching unit to make; And, A control unit for detecting an output voltage at the output terminal and generating a control signal to operate corresponding switching elements of the first switching unit and the second switching unit in two stages so that the detected output voltage is maintained within a specified voltage stability tolerance range Including; Among the control signals generated in the second step, the control element generated according to the first detected output voltage operates the corresponding switching element of the first switching unit to generate the first compensation voltage in the first compensation transformer. The corresponding switching element of the second switching unit is operated by the control signal generated according to the detection voltage generated on the secondary side of the main transformer which is supplied to the transformer primary side and is supplied with the first compensation voltage. 2) An automatic voltage regulator which generates a compensation voltage and supplies it to an output terminal to finally maintain the output voltage within a specified voltage stability allowable range. The method of claim 1, The main transformer forms nine tabs on the primary side, three tabs on the secondary side, The first switching unit includes switching elements of nine anti-parallel constituent thyristor modules corresponding to the nine taps of the primary transformer primary side, and the second switching unit includes the main transformer secondary side 3 And a switching element of three anti-parallel configuration thyristor modules corresponding to the four taps.

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