JP2000232735A - Voltage phase adjusting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to finely adjust the magnitude and phase of the voltage of a load-side line by, if the taps of a phase adjusting device are changed, by processing vector addition of a voltage corresponding to a differential by which the magnitude and the phase varied depending on the respective taps to the output voltage of the phase adjusting device. SOLUTION: A tap-changeable phase adjusting device 11 is constituted of a tapped transformer 13 for phase adjustment (installed at some midpoint in a distribution line) which is fed with the voltage Vr1 of a power supply-side line 1 and adjusts the phase of the load-side voltage Vr2 relative to a point of installation, and a tap changer 14 which changes taps according to a command. If a voltage ΔVO corresponding to the difference between a target voltage and the output voltage Vr2 of the tap-changeable phase adjusting device 11 is outputted from a static voltage adjuster 12 and the taps of the phase adjusting device 11 are changed, a voltage ΔVO the magnitude and phase of which varied depending on the respective taps is added to the output voltage Vr2 by vector. As a result, the voltage Vr3 of a load line 2 can be kept matched with the target voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage phase adjusting device for adjusting a voltage level and a voltage phase of a distribution system.

[0002]

2. Description of the Related Art The phase and voltage of a power distribution system are constantly changing due to changes in demand and supply. If the phase / voltage fluctuation is large, it affects the normal use or the life of various types of electric equipment of the consumer. Therefore, in order to adjust the voltage at the consumer at the load end by compensating for this phase and voltage, and to supply high-quality power, a voltage regulator or a voltage phase regulator is installed in the distribution system. Among them, the voltage phase adjuster controls the active power and the reactive power transmitted and received between the systems interconnected by a plurality of distribution systems in a predetermined direction and magnitude, and adjusts the local voltage of each system to an appropriate voltage. A voltage having a predetermined magnitude and phase is inserted into the system so as to fall within the range, and the magnitude of the voltage of the system and its voltage phase are adjusted.

FIG. 6 shows a power distribution system provided with a conventional voltage phase adjuster. In FIG.
2 is a load side line, and 3 is a voltage phase adjuster. The voltage phase adjuster 3 includes a voltage adjusting transformer T1 and a phase adjusting transformer T.
In the voltage adjusting transformer T1, shunt windings 4U, 4V, 4W and series windings 5U, 5V, 5W with taps for voltage adjustment are wound around an iron core (not shown), and are star-connected. Have been. This series winding 5 with a tap for voltage adjustment
The center taps of U, 5V and 5W are respectively connected to the primary terminals U1,
V1 and W1. Exciting windings 7U, 7V, 7W and phase adjusting tap windings 8U, 8V, 8W are wound around an iron core (not shown) in the phase adjusting transformer T2, and the exciting windings 7U, 7V, 7W are triangularly connected. In addition, each connection portion is connected to the primary terminals U1, V1, and W1. The center taps of the phase adjustment tap windings 8U, 8V, 8W are connected to voltage adjustment tap changers 6U, 6V,
Series winding 5U, 5 with voltage adjusting tap via 6W
V, 5W. Further, the phase adjustment tap windings 8U, 8V, 8W are connected to the secondary terminals U2, V2, W2 via the phase adjustment tap changers 9U, 9V, 9W, respectively (Japanese Patent Laid-Open No. 63-147209). Gazette).

The principle of changing the transformation ratio and the phase difference in the voltage phase adjuster configured as described above will be described with reference to a single phase voltage vector diagram shown in FIG. In the figure, O indicates a neutral point, and a vector OV indicates a V-phase primary terminal voltage. First, the voltage adjustment tap changers 6U, 6
When the taps of V and 6W are switched, for example, in the step-up direction, the vector VV 'is added to the vector OV of the primary terminal voltage by the voltage adjusting transformer T1 to obtain the vector OV'. On the other hand, tap switches 9U, 9V for phase adjustment,
When the taps are switched in the phase leading direction, for example, in each of 9W, a vector V'v having a component orthogonal to the vector OV 'is added to the vector OV by the phase adjusting transformer T2, and the phase of the primary terminal voltage vector OV is A vector Ov of the secondary terminal voltage having the angle β is obtained. Note that the dotted line indicates that a secondary terminal voltage having a phase angle β opposite to the above is obtained. In this way, the magnitude of the voltage and its voltage phase are adjusted to an adjustment point determined by selecting a predetermined tap. This adjustment point is determined by a combination of these taps, and one example is shown by a black point in FIG. The number of taps is, for example, 9 for phase adjustment for each phase,
Six voltage regulators are provided, and in this example, five phase regulators and three voltage regulators are shown to simplify the drawing.

[0005]

In the conventional voltage phase adjuster, as shown in FIG. 8, the adjustment point is each tap width (for example, in the case of a 6.6 [KV] type distribution line, the voltage adjustment width is Since the phase adjustment angle is limited to about 100 [V] and the phase adjustment angle is about 4 [degrees], there is a problem that it is not possible to finely adjust the magnitude of the voltage and its voltage phase.

Also, since the adjustment point is limited and fixed within the range shown by the dotted line in FIG. 8, there is a problem that the voltage and the voltage phase outside the adjustment range cannot be adjusted.

An object of the present invention is to provide a voltage phase adjusting device capable of finely adjusting a voltage magnitude and a voltage phase thereof without being restricted by a tap width.

The present invention further provides a voltage phase adjusting device capable of adjusting a voltage magnitude and a voltage phase thereof outside the adjustment range even when a situation that requires adjustment outside the adjustment range occurs. Is an issue.

[0009]

The present invention relates to a voltage phase adjusting device.

According to the first aspect of the present invention, a voltage of a power supply side line from a power supply is installed based on an installation point, which is installed in the middle of a distribution line, and a load-side voltage of the installation point is used as a reference. Tap-switching phase adjustment having at least a tap-adjusting phase-adjusting transformer having a phase-adjusting tap winding for adjusting a phase, and a tap switch for switching taps of the phase-adjusting transformer in accordance with a tap switching command. Secondary winding is inserted between the output of the tap-switching phase adjuster and the load side line from the load with reference to the installation point, and the induced voltage of the secondary winding is tapped switching-type phase adjustment Series transformer that superimposes on the output voltage of the transformer, and power conversion that inputs the voltage obtained from the distribution line side, generates a regulated voltage of variable magnitude and phase, and applies the regulated voltage to the primary winding of the series transformer Static voltage with at least The voltage of the load-side line is matched with the target voltage of the load-side line having the target phase angle determined from the magnitude of the voltage of the load-side line and the phase angle of the voltage of the load-side line with respect to the voltage of the power supply-side line. Voltage to control the power converter to output from the power converter an adjustment voltage necessary to induce a voltage to be applied to the output voltage of the tap-switching phase adjuster in the secondary winding of the series transformer to cause the voltage to be applied. And a phase control unit.

In the first aspect of the present invention, a voltage corresponding to the difference between the target voltage and the output voltage of the tap switching type phase adjuster is output from the static type voltage adjuster, and the tap of the phase adjuster is switched. However, the voltage corresponding to the difference whose magnitude and phase are varied according to each tap is vector-added to the output voltage of the phase adjuster, so that the voltage of the load side line always matches the target voltage. Thus, in the present invention, the target voltage (adjustment point) is set arbitrarily, whereas the adjustment point can be set only in steps in the past. That is, the magnitude of the voltage on the load side line and its voltage phase are finely adjusted. The adjustment range is
The target voltage (adjustment point) is arbitrarily set within the circle of the maximum value of the voltage output from the static voltage adjuster centered on the phase adjustment point by each tap of the phase adjuster, Moreover, the adjustment range is wider than before.

According to a second aspect of the present invention, the voltage phase control unit further comprises a difference between the target phase angle and the phase angle of the output voltage of the tap switching type phase adjuster with respect to the voltage of the power supply side line. When it is determined that the difference is equal to or larger than the phase adjustment amount by the tap, at least the tap adjustment command is given to the tap changer until the difference becomes equal to or less than the phase adjustment amount by one tap of the phase adjuster. is there.

According to the second aspect of the present invention, when it is determined that the difference between the target phase angle and the phase angle of the output voltage of the phase adjuster is equal to or more than the amount of phase adjustment by one tap of the phase adjuster. By switching the taps until the difference becomes equal to or less than the amount of phase adjustment by one tap of the phase adjuster,
Each time the tap is switched, the voltage output from the static voltage regulator decreases, and the thermal load on the static voltage regulator decreases accordingly. By making the difference between the phase angle of the output voltage and the phase angle by one tap or less, the thermal load on the static voltage regulator is reduced, so the radiator of this device is small and the capacity is small. Become smaller.

According to a third aspect of the present invention, the power converter includes a converter for converting an input voltage to a constant DC voltage, an inverter for converting an output voltage of the converter to an AC voltage and outputting a regulated voltage, An inverter control signal externally supplied so as to turn on / off a semiconductor switch element constituting the converter so that the DC voltage output from the converter is constant, and to generate an AC voltage having a predetermined magnitude and phase from the inverter. And a semiconductor switch control unit that controls on / off of a semiconductor switch element that constitutes the inverter according to the following.The voltage phase control unit includes a detection circuit that detects an output voltage of the tap switching type phase adjuster, and a load-side line. A target voltage setting section for setting a target voltage, and a target voltage of the load side line set by the target voltage setting section and a detection time. An adjustment voltage calculator for calculating a target value of the adjustment voltage from the output of the power converter; and a semiconductor switch of the power converter so as to reduce the difference between the actual output voltage of the power converter and the calculated target value of the adjustment voltage to zero. And an inverter control signal generation section that supplies an inverter control signal to the control section.

According to a fourth aspect of the present invention, the voltage phase control section further calculates a difference between the target phase angle and the phase angle of the output voltage of the tap switching type phase adjuster with respect to the voltage of the power supply line. And a tap switching command section that gives a tap switching command when the output of the phase difference calculating section is determined to be greater than or equal to the determination value by comparing the phase difference calculated by the phase difference calculating section with the set determination value. At least.

[0016]

FIG. 1 shows an example of the overall configuration of a voltage phase adjusting device according to the present invention. In FIG. 1, reference numeral 1 denotes a power line, 2 denotes a load line, and 10 denotes a line of the present invention. A voltage phase adjusting device according to

The voltage phase adjuster 10 includes a tap switching type phase adjuster 11, a static voltage adjuster 12, and a voltage phase controller 15. Tap switching type phase adjuster 11
Is a phase adjusting device that is installed in the middle of the distribution line and receives the voltage Vr1 of the power supply side line 1 from the power source with reference to the installation point and adjusts the phase of the voltage Vr2 on the load side with reference to this installation point. It comprises a phase-adjusting transformer 13 having taps having tap windings, and a tap switch 14 for switching the taps of the phase-adjusting transformer in accordance with a tap switching command.

The static voltage regulator 12 includes a primary winding 16a.
And the secondary winding 16b, and the secondary winding 16b is inserted between the output side of the tap switching type phase adjuster 11 and the load line 2 in parallel with the series transformer 16 from the distribution line side. A power converter 18 for converting a voltage obtained through the transformer 17 into an adjustment voltage ΔVi and applying the adjustment voltage ΔVi to the primary winding 16 a of the series transformer 16.

The power converter 18 includes a converter for converting a voltage supplied from the parallel transformer 17 into a constant DC voltage, and an inverter for converting the output of the converter into a regulated voltage (AC voltage) having a variable magnitude and phase. And a control unit for controlling the converter and the inverter,
The voltage obtained from the distribution line side through the parallel transformer 17 is converted into a regulated voltage ΔVi having a variable magnitude and phase, and the regulated voltage is applied to the primary winding 16 a of the series transformer 16.

The voltage phase controller 15 applies a voltage ΔVo to be added to the output voltage Vr2 of the tap switching type phase adjuster 11 to the secondary voltage of the series transformer 16 in order to make the voltage Vr1 of the load side line 2 coincide with the target voltage. The power converter 18 is controlled so that the adjustment voltage ΔVi required to be applied to the primary winding 16a of the series transformer 16 to be induced in the winding 16b is output from the power converter 18.

In the illustrated example, the primary side of the parallel transformer 17 is connected to the output side of the tap-switching type phase adjuster 11, and the output voltage of the phase adjuster 11 is stepped down by the parallel transformer 17 so that the power converter 18 is given.

Referring to FIG. 2, the configuration of the series transformer 16, the parallel transformer 17 and the power converter 18 is shown in detail. In FIG. 1, the overall configuration of the voltage phase adjustment device is shown by a single-line diagram, so that three-phase voltages and reference numerals indicating components are not distinguished from each other. In order to distinguish the three phases of U and V, u, V, and W indicate the three-phase voltages and three-phase parts, respectively.
Subscripts of v and w are added.

In the example shown in FIG. 2, the series transformer 16 is
Star-connected three-phase primary windings 16pu, 16pv and 1
6pw and secondary windings 16su, 16sv and 16
sw and have. Three-phase secondary winding 1 of series transformer 16
6su, 16sv and 16sw are transformers 1 for phase adjustment, respectively.
3 (not shown in FIG. 3) of three-phase output terminals 13u, 1
3v and 13w and the load-side lines 2u, 2v and 2w are connected between the phase adjustment transformer 13 and the load-side line 2w.
u, 2v and 2w are connected in series.

The parallel transformer 17 has delta-connected three-phase primary windings 17pu, 17pv and 17pw and also delta-connected secondary windings 17su, 17sv and 17sw. The three-phase input terminals are three-phase output terminals 13u, 13v, and 13 of the phase adjustment transformer 13, respectively.
w.

The power converter 18 includes a converter 18A for converting the output voltage of the parallel transformer 17 into a DC voltage, a power supply capacitor 18B for storing the DC voltage converted by the converter 18A, and a power supply capacitor 18B at both ends of the power supply capacitor 18B. DC voltage equal to the voltage of the distribution line 3
Converted into phase AC voltage and adjusted voltages ΔViu, ΔViv and ΔV
an inverter 18C for outputting as iw and a converter 18
A and a semiconductor switch control unit 18D for controlling a semiconductor switch constituting the inverter 18C.
Adjustment voltages ΔViu to ΔViw output from power converter 18
Can be appropriately adjusted by controlling on / off of a semiconductor switch element constituting the inverter 18C.

The illustrated converter 18A includes a diode D
u to Dw and Dx to Dz are connected by a three-phase full-wave bridge, and diodes Du, Dv, Dw and Dx, Dy,
A circuit in which semiconductor switching elements Su, Sv, Sw and Sx, Sy, Sz such as IGBTs (insulated gate transistors) are connected in anti-parallel to both ends of Dz, respectively, is a three-phase AC input terminal of this converter. Are connected to the three-phase output terminals of the parallel transformer 17.

The inverter 18C has a three-phase bridge connection of semiconductor switch elements Su 'to Sw' and Sx 'to Sz' such as IGBTs, and also has switch elements Su 'to Sw'.
A circuit in which feedback diodes Du 'to Dw' and Dx 'to Dz' are connected in anti-parallel to both ends of Sw 'and Sx' to Sz ', respectively, has a DC input terminal connected to both ends of the capacitor 18B. , And the AC output terminal is connected to the three-phase input terminal of the series transformer 16.

The semiconductor switch elements Su to Sw and Sx to Sz constituting the converter 18A and the inverter 18C
Of the semiconductor switch elements Su 'to Sw' and Sx
Semiconductor switch control unit 1 for controlling
8D is provided.

The semiconductor switch control unit 18D includes, for example, a CP
U, a converter control means for controlling the converter 18A so as to keep the voltage across the capacitor 18B constant by causing the CPU to execute a predetermined program, and an inverter control provided from the voltage phase control unit 15. And an inverter control means for controlling the inverter 18C according to the signal.

The semiconductor switch control unit 18D feeds back a detected value of the voltage across the capacitor 18B provided from a detection circuit (not shown) to maintain the voltage across the capacitor 18B at a set value, and to connect the voltage between both ends of the capacitor 18B. Generates a constant DC voltage. This DC voltage is supplied to inverter 18C as a power supply voltage.

The semiconductor switch control unit 18D also switches the switch elements Su 'to S on the upper side of the inverter 18C according to the inverter control signal supplied from the voltage phase control unit 15.
By controlling ON / OFF of w ′ and the switch elements Sx ′ to Sz ′ on the lower side in a predetermined order, the output of the tap-switching phase adjuster 11 is used to make the voltages of the load-side lines 2u to 2w coincide with the target voltage. Voltage Δ to be added to voltage
Vou to ΔVow are converted to the secondary windings 16su to 16su of the series transformer 16.
The adjustment voltages ΔViu to ΔViw necessary for inducing sw are output from the inverter 18C.

As shown in FIG. 3, the voltage phase control unit 15 shown in FIG.
T), the output voltage V of the tap switching type phase adjuster 11
a detection circuit 20 for detecting r2, and a voltage Vr3 of the load side line 2.
And a target voltage setting unit 21 that sets a target voltage Vra having a target phase angle Θra from the magnitude of the voltage and the phase angle of the voltage on the load side line 2 with respect to the voltage Vr1 on the power supply side line 1. An adjustment voltage calculator 22 for calculating a target value ΔVia of an adjustment voltage to be applied to the series transformer 16 from the target voltage Vra of the load side line 2 and the output of the detection circuit 20, and detection through an instrument voltage transformer (VT) (not shown). The feedback control is performed so that the difference between the actual output voltage ΔVi of the power converter 18 and the calculated target value ΔVia of the adjusted voltage becomes zero, and the inverter control signal is transmitted to the semiconductor switch control unit 18D of the power converter 18. And an inverter control signal generating section 23 for providing the signal.

The adjustment voltage calculator 22 calculates the difference between the target voltage Vra and the output voltage Vr2 of the tap switching type phase adjuster 11 obtained from the detection circuit 20, and uses the difference as the reciprocal of the voltage transformation ratio of the series transformer. To calculate the target value ΔVia of the adjustment voltage.

The inverter control signal generator 23 shown in FIG.
It is composed of a waveform shaping section 24 and a control signal output section 25. The waveform shaping unit 24 amplifies the difference ΔVia−ΔVi between the target value ΔVia of the adjustment voltage and the actual adjustment voltage ΔVi output from the power converter 18 by error. Control signal output unit 2
5 receives the signal obtained from the waveform shaping unit 24 and sets the inverter 18 so that the difference between the target value ΔVia of the adjustment voltage and the adjustment voltage ΔVi output from the power converter 18 becomes zero.
An inverter control signal is generated to turn on and off the semiconductor switch elements constituting C. The semiconductor switch control unit 18D in the power converter 18 controls on / off of the switch elements constituting the inverter 18C according to the inverter control signal, and outputs the adjustment voltage ΔVi having a magnitude equal to the target value ΔVia of the adjustment voltage from the inverter 18C. Output.

The voltage phase control section 15 sets the target phase angle Θra of the load side line 2 set by the target voltage setting section 21.
And a phase difference calculator 30 for calculating the difference between the voltage Vr1 of the power supply line 1 obtained from the detection circuit 20 and the phase angle β of the output voltage Vr2 of the tap switching type phase adjuster 11, and the phase difference calculator 30 Is compared with the determination value た in which the amount of phase adjustment by one tap of the tap type phase adjuster 11 is set, and it is determined that the output of the phase difference calculation unit 30 is equal to or greater than the determination value. A tap switching command section 31 for giving a tap switching command to the tap switching device 14 until the difference α becomes equal to or smaller than the determination value Θ. The tap switching command unit 31 outputs the output α = (Θ
If (ra−β) is α> 0 and α> Θ, it is determined that the tap switching direction is on the leading side and α <0
If | α |> Θ, it is determined that the tap switching direction is on the lag phase side, and α ≦ Θ or | α
The tap change command is given to the tap changer 14 until | ≦ Θ. Further, when a specific tap selection signal output from the specific tap selection unit 32 is input, the tap switching command unit 31 outputs a specific tap switching command for switching to a specific tap. Or one of them is output.

Here, the operation of the voltage phase adjusting device according to the present invention will be described with reference to the vector diagram shown in FIG. As shown in FIG. 1, Vr1, Vr2, Vr3, and ΔVo denote the voltage of the power supply line 1, the output voltage of the tap-switching phase adjuster 11, the voltage of the load line 2, and the series transformer 16 as shown in FIG. Of the induced voltage. Vra is the target voltage, Θra is the target phase angle, Θ is the judgment value, β is the phase angle of Vr2, α is Θra and β
Is the phase difference between Note that (t0), (t1), and (t2) are added to the above symbols so that the passage of time can be understood.

To simplify the description of the above operation, assuming that the tap position of the tap switching type phase adjuster 11 is the center tap and a certain target voltage Vra is given at time t0, Vr2 (t0) at time t0 Becomes the same as Vr1 (t0) at time t0. First, at time t0, the target voltage Vra and this Vr2
From (t0), ΔVo (t0) at time t0 is calculated.
Vo (t0) is vector-added to Vr2 (t0),
Vr3 instantaneously matches the target voltage Vra. On the other hand, β (t0) at time t0 is not shown but becomes zero,
Since α (t0) at time t0 is α (t0) = {ra−β (t0)>}, the tap type phase adjuster 11 switches one tap slightly after time t0, and sets the switching time to t1. Then, at time t1, Vr2 (t0) changes to Vr2 (t1). Next,
At time t1, ΔVo (t1) at time t1 is calculated from target voltages Vra and Vr2 (t1), and ΔVo (t1) is calculated as ΔVo (t0).
Is added to Vr2 (t1) instead of Vr3, so that Vr3 remains equal to the target voltage Vra even when the tap is switched. On the other hand, at time t1, β (t0) changes to β (t1) and at time t1
Since α (t1) at 1 is α (t1) = {ra−β (t1)>},
Further, one tap is switched in the same direction with a slight delay from time t1, and when the switched time is t2, Vr2 (t1) changes to Vr2 (t2) at time t2. Subsequently, at time t2, ΔVo (t2) at time t2 is calculated from target voltages Vra and Vr2 (t2).
Is calculated, and ΔVo (t2) is replaced with Vo (t1) instead of Vo (t1).
By being added to r2 (t2), Vr3 remains equal to the target voltage Vra. On the other hand, at time t2, β (t1) is changed to β (t
2), α (t2) at time t2 is α (t2) = Θra−β (t2) <Θ, as is clear from FIG. Will be maintained.

As described above, the voltage ΔVo corresponding to the difference between the target voltage Vra and the output voltage Vr2 of the tap switching type phase adjuster 11 is output from the static voltage adjuster 12, and the tap of the phase adjuster 11 is turned off. Even if it changes, the voltage Vr3 of the load side line 2 will always coincide with the target voltage Vra by vector-adding ΔVo, whose magnitude and phase are varied according to each tap, to Vr2. In contrast to the fact that the adjustment point can only be set in stages, in the present invention, the target voltage (adjustment point) can be set arbitrarily. That is, the magnitude and the voltage phase of the voltage Vr3 of the load side line 2 can be finely adjusted. The adjustment range is the voltage ΔV output from the static voltage regulator.
Assuming that the maximum value of o is a circle shown in FIG. 5, as shown in FIG. Therefore, the target voltage (adjustment point) can be set arbitrarily within this circle, and the adjustment range can be made wider than before.

When it is determined that the difference between the target phase angle and the phase angle of the output voltage of the phase adjuster is equal to or greater than the amount of phase adjustment by one tap of the phase adjuster, the difference is determined by the phase adjuster. By switching the taps until the amount of phase adjustment by one tap becomes equal to or less than the phase adjustment amount, ΔVo output from the static voltage regulator 12 every time the tap is switched becomes small,
Accordingly, the thermal burden on the static voltage regulator 12 is reduced. In the steady state, the thermal load on the static voltage regulator 12 is reduced by making the difference between the target phase angle Θra and the phase angle β of the output voltage Vr2 of the phase regulator 11 equal to or less than the amount of phase adjustment by one tap. It is getting smaller. Therefore, the radiator of this device can be small, and the capacity can be reduced.

In the present invention, when the power factor of the power distribution system is permanently bad and the phase adjustment amount corresponding to the power factor is known in advance, the phase adjustment amount can be compensated to the maximum. A specific tap may be selected in advance, a specific tap switching command may be output, and the specific tap may be fixed.

In the present invention, the voltage obtained from the distribution line side is input to the power converter.
The purpose is to use the voltage supplied through the distribution line as the input voltage of the power converter, and various modifications can be considered for extracting the voltage input to the power converter.

Since the static voltage regulator 12 is provided between the tap switching type phase adjuster 11 and the load side line 2, in order to simplify the configuration of the device, for example, the tap switching type phase regulator is used. Is preferably input to the parallel transformer 17, and the output voltage of the parallel transformer is input to the power converter 18. However, the present invention is not limited to such a configuration. For example, the voltage of the power supply side line 1 may be input to the power converter through a parallel transformer. Further, the voltage of the load side line 2 may be input to the power converter through a parallel transformer.

The voltage phase adjusting device according to the present invention uses a tap switching type phase adjuster in which the output voltage changes when the tap of the phase adjusting transformer is changed, but the tap in which the output voltage does not change is used. A switchable phase adjuster can also be used.

Further, the voltage phase adjusting device according to the present invention comprises:
A voltage phase control unit corresponding to each phase of the system is provided to control the adjustment voltages applied to the three-phase lines from the three-phase power converter through the series transformer, respectively, so that the three-phase line voltages are unbalanced. Can also be suppressed.

Further, the voltage phase adjusting device according to the present invention can be used as an uninterruptible switching device capable of uninterruptedly linking the systems at a linking point such as a high-voltage different system where the phase difference and the voltage difference are large.

Further, the voltage phase adjusting device according to the present invention comprises:
If the static voltage regulator 12 fails, it can also function as a phase regulator.

Further, the voltage phase adjuster according to the present invention comprises a tap switching type phase adjuster 11 and a static voltage adjuster 1.
2 can be configured integrally or separately, and when configured separately, the voltage phase controller 15 may be attached to either one.

[0048]

As described above, according to the first and third aspects of the present invention, the voltage corresponding to the difference between the target voltage and the output voltage of the tap-switching phase adjuster is output from the static voltage adjuster. Therefore, even if the taps of the phase adjuster are switched, the voltage corresponding to the above-described difference whose magnitude and phase are changed according to each tap is vector-added to the output voltage of the phase adjuster. Although the adjustment point could only be set step by step, the target voltage (adjustment point) can now be set arbitrarily, and the magnitude of the voltage on the load side line and its voltage phase can be finely adjusted. can do. Further, the adjustment range is within the circle of the maximum value of the voltage output from the static voltage regulator centered on the phase adjustment point by each tap of the phase regulator, so that the target voltage (adjustment point) is Can be set arbitrarily, and the adjustment range can be made wider than before.

According to the second and fourth aspects of the present invention, it is determined that the difference between the target phase angle and the phase angle of the output voltage of the phase adjuster is equal to or more than the amount of phase adjustment by one tap of the phase adjuster. The tap is switched until the difference becomes equal to or less than the amount of phase adjustment by one tap of the phase adjuster. In a steady state, the difference between the target phase angle and the phase angle of the output voltage of the phase adjuster is changed. Is set to be equal to or less than the amount of phase adjustment by one tap, so that the thermal burden on the static voltage regulator is reduced, and the radiator and the capacity of this device can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an overall configuration of a voltage phase adjustment device according to the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a voltage phase control unit used in the voltage phase adjustment device of FIG. 1;

FIG. 3 is a circuit diagram showing a configuration example of a power converter used in the voltage phase adjusting device of FIG. 1;

FIG. 4 is a voltage vector diagram for explaining the operation of the voltage phase adjusting device according to the present invention.

FIG. 5 is a diagram showing an adjustment range by the voltage phase adjustment device according to the present invention.

FIG. 6 is a connection diagram showing a configuration of a conventional voltage phase adjuster.

FIG. 7 is a voltage vector diagram showing the principle of voltage phase adjustment of a conventional voltage phase adjuster.

FIG. 8 is a diagram showing adjustment points by a conventional voltage phase adjuster.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply side line 2 Load side line 10 Voltage phase adjuster 11 Tap switching type phase adjuster 12 Static voltage adjuster 13 Phase adjusting transformer 14 Tap changer 15 Voltage phase control unit 16 Series transformer 17 Parallel transformer 18 Power converter 20 Detection circuit 21 Target voltage setting unit 22 Adjustment voltage calculation unit 23 Inverter control signal generation unit 30 Phase difference calculation unit 31 Tap switching command unit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Sakae Fujine 3-3-22 Nakanoshima, Kita-ku, Osaka-shi, Osaka Inside Kansai Electric Power Company (72) Inventor Koichi Harada 2-1-1 Tagawa, Yodogawa-ku, Osaka-shi, Osaka 11 Daihen Co., Ltd. (72) Inventor Yoshiaki Tsuda 2-1-1 Tagawa, Yodogawa-ku, Osaka-shi, Osaka F-term (reference) 5G066 DA01 DA07 5H420 BB12 CC04 CC08 DD03 DD08 EA10 EA20 EA29 EA30 EA43 EA45 EB05 EB38 EB39 EB40 FF03 FF25 GG01

Claims (4)

[Claims] 1. A phase adjuster which is installed in the middle of a distribution line and inputs a voltage of a power supply side line from a power supply with reference to an installation point, and adjusts a phase of a voltage on a load side with reference to the installation point. A tap-changing phase adjuster having at least a tap-equipped transformer having a tap winding having a tap winding, and a tap switch for switching taps of the phase-adjusting transformer in accordance with a tap switching command; and the tap. A secondary winding is inserted between an output side of the switching type phase adjuster and a load side line from a load with reference to the installation point, and the induced voltage of the secondary winding is adjusted by the tap switching type phase adjuster. A series transformer to be superimposed on the output voltage of the series transformer, and a voltage obtained from the distribution line side is input to generate a regulated voltage having a variable magnitude and phase, and the regulated voltage is applied to a primary winding of the series transformer. At least a power converter A static voltage regulator, and a target voltage of the load-side line having a target phase angle determined from the magnitude of the voltage of the load-side line and the phase angle of the voltage of the load-side line with respect to the voltage of the power-supply-side line. Converting the adjustment voltage necessary for inducing a voltage to be applied to the output voltage of the tap switching type phase adjuster to the secondary winding of the series transformer to match the voltage of the load side line with the power conversion. And a voltage phase control unit that controls the power converter so as to output the power from the power converter. 2. The voltage phase control unit further comprises: a difference between the target phase angle and a phase angle of an output voltage of the tap-switching type phase adjuster with respect to a voltage of the power supply side line for one tap of the phase adjuster. When it is determined that the difference is equal to or more than the phase adjustment amount, the voltage is at least configured to give a tap switching command to the tap changer until the difference becomes equal to or less than the phase adjustment amount by one tap of the phase adjuster. Phase adjustment device. 3. The power converter includes a converter that converts an input voltage into a constant DC voltage, an inverter that converts an output voltage of the converter into an AC voltage and outputs a regulated voltage, and output from the converter. A semiconductor switch element constituting the converter is turned on / off so as to keep the DC voltage constant, and the semiconductor switch element is turned on / off in response to an inverter control signal externally applied so as to generate an AC voltage having a predetermined magnitude and phase from the inverter. A semiconductor switch control unit that controls on / off of a semiconductor switch element that constitutes an inverter, wherein the voltage phase control unit includes a detection circuit that detects an output voltage of the tap switching type phase adjuster; A target voltage setting unit for setting a target voltage, a target voltage of the load side line set by the target voltage setting unit, An adjustment voltage calculation unit that calculates a target value of the adjustment voltage from an output of the output circuit; and the power control unit that sets a difference between an actual output voltage of the power converter and the calculated target value of the adjustment voltage to zero. 3. The voltage phase adjusting device according to claim 1, further comprising: an inverter control signal generating unit that supplies an inverter control signal to a semiconductor switch control unit of the converter. 4. The phase difference calculation unit further calculates a difference between the target phase angle and a phase angle of an output voltage of the tap switching type phase adjuster with respect to a voltage of the power supply line, A tap switching command unit that gives a tap switching command when the output of the phase difference calculation unit is determined to be equal to or greater than the determination value by comparing the phase difference calculated by the phase difference calculation unit with the determined determination value; The voltage phase adjustment device according to claim 1, further comprising at least: