JP5171545B2 - Home voltage regulation system - Google Patents

Description

  The present invention relates to a home voltage regulation system.

  The three-phase AC power generated at the power plant is transmitted to the substation via a three-phase three-wire transmission line, the voltage is lowered at the substation, and further extended from the breaker at the substation. Supplied to the load of each household (small-scale consumer) through a three-phase AC distribution line such as a three-phase three-wire system. In addition, in a three-phase AC distribution line installed by a utility pole, the three-phase may occur when the distribution line voltage deviates from a predetermined voltage range due to a voltage drop caused by the line constant length or when a heavy single-phase load is connected. There are cases where the voltage balance of each phase is lost (three-phase voltage imbalance). Therefore, voltage compensation devices such as automatic voltage regulator (AVR) and automatic power factor regulator (AQR) are installed on substations and distribution lines as countermeasures for voltage fluctuations in distribution lines. ing. In addition, for example, Patent Document 1 discloses a control center 11 that eliminates load imbalance in a three-phase circuit by switching a phase load in which a maximum current appears to a phase in which a minimum current is recognized. Has been.

By the way, the electric power sent by the three-phase AC distribution line from the substation to the home is lowered to a single-phase voltage of 100 V or 200 V by a pole transformer provided on the power pole for laying the distribution line. It is drawn in to the entrance of each household through. A single-phase two-wire system or a single-phase three-wire system is generally used as a distribution line system from the service entrance to a household load (such as home appliances). The single-phase two-wire system means that one voltage line taken out from both ends of the secondary winding of the transformer in the distribution board or distribution board and one neutral line that is grounded It is a method of connecting to a single-phase load. The single-phase three-wire system is a grounded neutral wire taken out from the intermediate point of the secondary winding of the transformer in the distribution board or distribution board, and the secondary winding of the transformer. It is a distribution line system that is connected to a single-phase load in the home by two voltage lines taken out from both ends of the line. In addition, according to the single-phase three-wire system, for example, when two voltage lines supply a voltage of 100 V, the 200 V household load can be covered by the two voltage lines. One intermediate line can cover 100V household load. For distribution lines connected to household single-phase loads, such as the single-phase two-wire system and single-phase three-wire system as described above, the distribution panel will be installed by electric wiring work in consideration of the usage status of the single-phase load. It is wired in advance.
JP 2004-31848 A

  In recent years, private power generation facilities (distributed power sources) using natural energy such as wind power generation and solar power generation have begun to spread in the home. In-house power generation facilities are generally connected to a single-phase distribution line at home by converting generated direct current into single-phase alternating current by a single-phase inverter. For this reason, if the spread of interconnected private power generation facilities expands, it becomes impossible to ignore the influence of voltage unbalance in each phase in the three-phase AC distribution line on the distribution system side.

  In addition, with the spread of all electrification and the like, further increase in the power consumption of household loads is expected. For this reason, for example, among the single-phase three-wire distribution lines in the home consisting of the a-phase (voltage line), b-phase (neutral line), and c-phase (voltage line), the a-phase voltage is the amount of power used. When a large number of loads are connected and drop, the performance of household single-phase loads connected to the a-phase (voltage line) and b-phase (neutral line) deteriorates or the operation is performed as specified. There is no fear.

  The forecast of future power supply and demand as described above is due to the spread of private power generation facilities and the increase in the amount of electric power used by household single-phase loads. ), The voltage fluctuation of each phase of the three-phase AC distribution line on the distribution system side could not be suppressed, and as a result, the voltage of each phase of the three-phase distribution line drawn into the household inlet There is also a risk that it will affect.

  This invention is made | formed in view of the said subject, The main objective is the said 1 among the three distribution lines drawn into the household which has one neutral wire and two voltage wires. It is possible to adjust the two-phase voltage supplied to the single-phase load of the home to be within a predetermined voltage reference range by the neutral line of the book and one of the two voltage lines. Is to provide a household voltage regulation system.

  The main present invention for solving the above-mentioned problems is that one of the three distribution lines drawn into a home having one neutral line and two voltage lines, the one neutral line and the two A voltage regulating system for home use that supplies a two-phase voltage to a single-phase load of the household through one voltage line of the two voltage lines, and regulates the two-phase voltage. A two-phase selection device that selects one voltage line from the two voltage lines that supply a two-phase voltage to the single-phase load together with a neutral line, and the two-phase selection device includes the two A voltage detection unit that detects each voltage of the voltage line; a voltage determination unit that determines whether each voltage of the two voltage lines detected by the voltage detection unit deviates from a predetermined voltage reference range; Based on the determination result of the voltage determination unit, a two-phase power is supplied to the single-phase load together with the one neutral wire. And having a, a voltage line selection unit for selecting one of the voltage lines that do not depart from the voltage reference range from the two voltage line for supplying a.

  Moreover, in the above-described home voltage regulation system, the voltage line selection unit is configured such that one of the two voltage lines selected is the voltage based on a determination result of the voltage determination unit. When the other voltage line out of the two reference voltage lines deviates from the reference range and does not deviate from the voltage reference range, the one voltage line is switched to the other voltage line. That's good.

  Further, in the above-described home voltage regulation system, the power factor compensation device that compensates the power factor of the single-phase load between the selection device and the single-phase load, the power factor compensation device, A power factor detection unit that detects a power factor of the single phase load based on a two-phase voltage and current supplied to the single phase load, and a power factor detected by the power factor detection unit is within a predetermined power factor reference range. A power factor determination unit that determines whether or not to deviate, and the power factor determination unit that determines that the power factor detected by the power factor detection unit deviates from the power factor reference range by the power factor determination unit. It is good also as having a power factor compensation part which compensates for the difference of the upper and lower limits which define a range, and the above-mentioned detected power factor.

  Further, in the above-described home voltage regulation system, the power factor detection unit is configured such that each voltage of the two voltage lines detected by the voltage detection unit based on a determination result of the voltage determination unit is the voltage reference. When deviating from the range, the power factor of the single-phase load may be detected.

  Further, in the above-described home voltage regulation system, a tap switching transformer is provided between the two-phase selection device and the power factor compensation device, and the power factor compensation device is supplied to the single-phase load. A line voltage detector for detecting a line voltage of the two-phase voltage, and a line for determining whether or not the line voltage detected by the line voltage detector departs from a predetermined line voltage reference range When the line voltage detected by the line voltage determining unit and the line voltage determining unit is determined to deviate from the line voltage reference range, the line voltage reference range is determined. It is good also as a tap switching control part which switches the tap of the said tap switching transformer according to the difference of the upper and lower limits and the said detected line voltage.

  Further, in the above-described voltage regulation system for home use, the two-phase selection device, the tap switching transformer, and the power factor compensation device are configured to connect a three-phase AC distribution line installed on a power pole to a single-phase three-wire system. It is good also as providing between the drawing-in port of the household drawn in with a distribution line to the single phase load of the said household. The two-phase selection device, the tap switching transformer, and the power factor compensation device may be mounted on an integrated device, or the integrated device may be a household distribution board. It is good.

  Further, in the above-described home voltage regulation system, the two-phase selection device is provided on a power pole for laying a three-phase AC distribution line, and the tap switching transformer and the power factor compensation device are the two-phase devices. Being provided between a household inlet through a single-phase two-wire distribution line consisting of one voltage line selected by the selection device and one neutral line to the household single-phase load; It is good. The tap switching transformer and the power factor compensation device may be mounted on an integrated device, or the integrated device may be a home distribution board.

  In addition, the problems disclosed in the present application and the solutions thereof will be clarified by the column of the best mode for carrying out the invention and the drawings.

  As shown in the present invention, it is possible to provide a home voltage regulation system capable of adjusting two-phase voltages supplied to a home single-phase load so as to be within a predetermined voltage reference range.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

<<< Home voltage regulation system according to the first embodiment >>>
=== Configuration Example of a Home Voltage Regulation System ===
FIG. 1 is a diagram showing a configuration of a domestic voltage regulation system 100 according to the first embodiment of the present invention.

  The home voltage regulation system 100 anticipates the future spread of private power generation facilities and the increase in the amount of power consumed by each household load. As a supplementary measure for voltage fluctuations on the existing distribution system side, the home voltage regulation system 100 is provided to each home. It is a system that is implemented with the aim of spreading. The home voltage regulation system 100 is an existing home distribution board (integrated device) provided between distribution lines between a home inlet 10 and a single-phase load 20 that is a household load such as home appliances. Implemented as an alternative or additional device.

  Specifically, one neutral wire 12b that is grounded and two voltage wires 12a and 12c that supply a voltage of, for example, 100 V from a three-phase three-wire three-phase AC distribution line installed on a power pole. A single-phase three-wire distribution line having the above is drawn into the service port 10. The home voltage regulation system 100 includes two voltage lines 12a that supply a two-phase voltage to the single-phase load 20 together with one neutral line 12b based on the voltage status of the two voltage lines 12a and 12c. The system aims to adjust the voltage supplied to the single-phase load 20 so as to be within a predetermined voltage reference range by selecting one voltage line among 12c.

  The household voltage regulation system 100 as described above includes a power receiving side terminal 14b connected to one neutral wire 12b, and power receiving side terminals 14a and 14c connected to two voltage wires 12a and 12c, respectively. Two load-side terminals 16 a and 16 b connected to the single-phase load 20 are included. The a-phase voltage Va, the b-phase voltage Vb, and the c-phase voltage Vc are applied to the power receiving terminals 14a, 14b, and 14c, respectively. Voltages corresponding to the a-phase voltage Va or c-phase voltage Vc (hereinafter referred to as P-phase voltage Vp) and b-phase voltage Vb (hereinafter referred to as N-phase voltage Vn) are simply applied from the load side terminals 16a and 16b. It is supplied to the phase load 20.

  The household voltage regulation system 100 includes a two-phase selection device 120, a tap switching transformer 140, and a power factor compensation device 160.

  The two-phase selection device 120 includes a control unit 122 and a two-phase selection unit 124, and includes one neutral wire 12b connected to the power receiving side terminal 14b and two wires connected to the power receiving side terminals 14a and 14c. This is a device for selecting one voltage line from the voltage lines 12a and 12c. That is, as the patterns selected by the two-phase selection device 120, there are two patterns of the voltage line 12a and the neutral line 12b, and the voltage line 12c and the neutral line 12b.

  The control unit 122 individually monitors the a-phase voltage Va, the b-phase voltage Vb, and the c-phase voltage Vc applied to the power receiving side terminals 14a, 14b, and 14c, and detects the voltage of each phase (voltage detection Part). The function is realized by hardware such as a voltmeter or AD converter and CPU software, for example. Note that the b-phase voltage Vb does not have to be detected as 0V.

  Further, the control unit 122 sets a voltage reference range (Vra ± ΔV, Vrb ± ΔV, Vrc ± ΔV) in which the detection voltage of each phase is determined in a range of ± ΔV with respect to the respective reference voltages Vra, Vrb, and Vrc. It has a function (voltage determination unit) for determining whether or not to deviate. The function is realized by hardware such as a comparator or CPU software, for example. When the detection voltage of each phase exceeds the upper limit voltage (Vra + ΔV, Vrb + ΔV, Vrc + ΔV), the upper limit is deviated. When the detection voltage of each phase is lower than the lower limit voltage (Vra−ΔV, Vrb−ΔV, Vrc−ΔV) Is the lower limit.

  Further, the control unit 122 has a function of determining whether or not the voltage line can be selected by the two-phase selection unit 124 based on the detected voltage of each phase, and a state signal S indicating the determination result is described later. It outputs toward the control part 164 with which the power factor compensation apparatus 160 is provided. The function is realized by, for example, a logic circuit or CPU software. When it is determined that the selection by the two-phase selection unit 124 is possible, the voltage of one voltage line (the a-phase voltage Va or the c-phase voltage Vc) of the two voltage lines 12a and 12c currently selected. ) Is an upper limit deviation or a lower limit deviation, and it is determined that the voltage of the other voltage line not currently selected does not deviate from the voltage reference range. When it is determined that selection by the two-phase selection unit 124 is possible, the control unit 122 outputs a control signal SW1 for switching to the unselected voltage line to the two-phase selection unit 124. The control unit 122 selects the two-phase selection unit 124 when the voltages (a-phase voltage Va and c-phase voltage Vc) of the two voltage lines 12a and 12c are both out of the upper limit or the lower limit. Judged as impossible.

  The two-phase selection unit 124 includes a voltage line selection unit 125 and a neutral line selection unit 126. Based on a control signal SW1 from the control unit 122, the two-phase selection unit 124 includes two voltage lines 12a and 12c. Select one voltage line. In the present embodiment, the selection of the neutral line 12b is fixed.

  In the voltage line selection unit 125, two voltage lines 12 a and 12 c are connected via the control unit 122. Based on the control signal SW1 from the control unit 122, the voltage line selection unit 125 applies the a-phase voltage Va of the voltage line 12a to be applied to one terminal of the primary winding of the tapped transformer 142 or the c-phase of the voltage line 12c. The voltage Vc is selected. The neutral line selection unit 126 is connected to the neutral line 12b via the control unit 122 in the same manner as the voltage line selection unit 125. However, the selection operation is not performed, and the b-phase voltage Vb of the neutral line 12b is set. Applied to the other terminal of the primary winding of the tapped transformer 142. In addition, you may provide the function which replaces each function of the voltage line selection part 125 and the neutral line selection part 126 with the polarity (winding direction) of the primary winding of the transformer 142 with a tap.

  The tap switching transformer 140 includes a tap transformer 142 and a tap switch 144, and is extracted from the secondary winding of the tap transformer 142 by adjusting the number of turns of the primary winding of the tap transformer 142. The secondary voltage, that is, the two-phase voltage (P-phase voltage Vp, N-phase voltage Vn) supplied to the single-phase load 20 from the load side terminals 16a and 16b is adjusted.

  In the transformer 142 with a tap, the voltage (a phase voltage Va or c phase voltage Vc) of one voltage line selected by the voltage line selection unit 125 is applied to one terminal of the primary winding, and the primary winding The b-phase voltage Vb of the neutral wire 12b is applied from the voltage line selector 125 to the other terminal. Both terminals of the secondary winding of the tapped transformer 142 are connected to the power factor compensator 162 of the power factor compensator 160. When the turn ratio of the primary winding and the secondary winding of the tapped transformer 142 is N1 / N2, the secondary voltage extracted from the secondary winding of the tapped transformer 142 is the ideal voltage transformer. In this case, it can be expressed as “(Va−Vb) · N1 / N2” or “(Vc−Vb) · N1 / N2”.

  The tap switch 144 selects a tap by selecting one of a plurality of taps drawn from the primary winding of the transformer 142 with a tap based on the control signal SW3 from the control unit 164 of the power factor compensation device 160. The number of turns N1 of the primary winding of the attached transformer 142 is adjusted. When N1 (TAP) represents that the number of turns N1 of the primary winding is variable, the secondary voltage taken out from the secondary winding of the tapped transformer 142 is “(Va−Vb) · N1 (TAP)”. / N2 ”or“ (Vc−Vb) · N1 (TAP) / N2 ”.

  The power factor compensation device 160 is configured by a control unit 162 and a power factor compensator 164 and is a device that performs power factor compensation of the single phase load 20 so as to suppress fluctuations in the two-phase voltage supplied to the single phase load 20. is there. Note that if the power factor θ of the single-phase load 20 varies with an increase or decrease in the inductance component (inductive load) or the capacitance component (capacitive load) of the single-phase load 20 connected to the load-side terminals 16a and 16b, The two-phase voltage supplied to the phase load 20 also varies. In this case, the power factor compensator 160 compensates the power factor of the single-phase load 20 in order to suppress fluctuations in the two-phase voltage supplied to the single-phase load 20.

  When the control unit 162 receives the state signal S indicating that the selection is impossible from the control unit 122, the control unit 162 supplies the two-phase voltage and the single-phase load 20 supplied to the single-phase load 20 from the load-side terminals 16a and 16b. And a function (power factor detector) for detecting the power factor θ of the single-phase load 20 based on the current I flowing through the inverter. The function is realized by, for example, hardware such as a voltmeter, an ammeter, and an integration circuit, or an AD converter and CPU software. Further, the control unit 162 determines whether or not the detected power factor θ deviates from a power factor reference range (θr ± Δθ) determined within a range of ± Δθ with reference to the reference power factor θr (power factor). Determination unit). The function is realized by hardware such as a comparator or CPU software, for example. When the detected power factor θ exceeds the upper limit power factor (θr + Δθ), the upper limit deviation (too much advance) is assumed. When the detected power factor θ falls below the lower limit power factor (θr−Δθ), the lower limit deviation (delay) Too). When it is determined that the detected power factor θ is an upper limit deviation or a lower limit deviation, the power factor reference range is set to converge the power factor θ of the single-phase load 20 to the power factor reference range (θr ± Δθ). A function (power factor compensation function) for compensating for the difference (θ− (θr ± Δθ)) between the upper and lower limits (θr + Δθ, θr−Δθ) and the detected power factor θ, and for performing the power factor compensation The control signal SW2 is output toward the power factor compensator 264.

  Furthermore, the control part 162 has a function (line voltage detection part) which detects the line voltage v of the two-phase voltage supplied to the single phase load 20 from the load side terminals 16a and 16b. This function is realized by hardware such as a differential amplifier or AD converter and CPU software. The control unit 162 also determines whether or not the detected line voltage v deviates from a line voltage reference range (vr ± Δv) determined within a range of ± Δv with reference to the reference line voltage vr. (Line voltage determination unit). This function is realized by hardware such as a comparator or AD converter and CPU software. When the line voltage v exceeds the upper limit line voltage (vr + Δv), the upper limit is deviated. When the line voltage v falls below the lower limit line voltage (vr−Δv), the lower limit deviates. When it is determined that the line voltage v is an upper limit deviation or a lower limit deviation, the difference between the upper and lower limits that define the line voltage reference range (vr ± Δv) and the detected line voltage v (v− (vr The control signal SW3 for switching the tap of the primary winding of the transformer with tap 142 according to ± Δv)) is output to the tap switch 144.

  The power factor compensator 164 has a function (power factor compensation unit) for compensating the power factor θ of the single-phase load 20 based on the control signal SW2 from the control unit 162. Specifically, when the control signal SW2 indicates that the power factor θ of the single-phase load 20 deviates from the upper limit (too much advance), compensation by the compensation inductance L for reducing (delaying) the power factor θ, and / Or cancel compensation by the compensation capacitor C to increase (advance) the power factor θ. On the other hand, when the control signal SW2 indicates that the power factor θ of the single-phase load 20 deviates from the lower limit (too late), compensation by the compensation capacitor C for increasing (advancing) the power factor θ, and / or Compensation cancellation of the compensation inductance L is performed to lower (delay) the power factor θ. The power factor compensator 164 has a plurality of compensation inductances L and compensation capacitors C, and selects the plurality of compensation inductances L and compensation capacitors C in a stepwise manner based on the control signal SW2 from the control unit 162. May be.

=== Example of Overall Operation of Home Voltage Regulator System ===
FIG. 2 is a flowchart showing an overall operation flow of the home voltage regulation system 100.

  The control unit 122 of the two-phase selection device 120 detects the three-phase a-phase voltage Va, b-phase voltage Vb, and c-phase voltage Vc supplied to the power receiving terminals 14a, 14b, and 14c (S200). It is determined whether or not the voltage deviates from the voltage reference range (Vr ± ΔV) (S201). When it is determined that the voltage of each phase does not deviate from the voltage reference range (Vr ± ΔV) (S201: NO), the process returns to S200. When it is determined that one of the voltages of each phase deviates from the voltage reference range (Vr ± ΔV) (S201: YES), the voltage line currently selected by the voltage line selection unit 125 is not selected. It is determined whether or not switching to a voltage line is possible (S202). A state signal S indicating the determination result is output to the control unit 162 of the power factor compensation device 160.

  When the voltage of one of the two voltage lines 12a and 12b currently selected by the voltage line selection unit 125 deviates from the upper limit (S202: YES) , S203: YES), the voltage line is selected as the control signal SW1 for switching the currently selected voltage line to the other voltage line that is not currently selected and does not deviate from the voltage reference range (Vr ± ΔV). Output to the unit 125, and return to S200. As a result, the voltage line selection unit 125 selects the other voltage line. On the other hand, when the voltage of one voltage line currently selected by the voltage line selection unit 125 deviates from the lower limit (S203: NO, S205), the currently selected voltage line is not currently selected. A control signal SW1 for switching to the other voltage line not deviating from the voltage reference range (Vr ± ΔV) is output to the voltage line selection unit 125, and the process returns to S200. As a result, the voltage line selection unit 125 selects the other voltage line.

  When the state signal S received from the control unit 122 indicates that selection by the voltage line selection unit 125 is impossible (S202: NO), the control unit 162 of the power factor compensation device 160 receives the load side terminals 16a and 16b. The power factor θ of the single-phase load 20 is detected based on the two-phase voltage supplied to the single-phase load 20 and the current I flowing through the single-phase load 20 (S207), and the detected power factor θ is the power factor reference range. It is determined whether or not (θr ± Δθ) is deviated (S208). When the detected power factor θ exceeds the upper limit power factor (θr + Δθ) (S208: YES, S209: YES), for example, when the inductance component of the single-phase load 20 decreases or the capacitance component increases, the single-phase load 20 Compensation for lowering the power factor θ is performed, and the process returns to S200. Specifically, the power factor compensation is canceled by the compensation capacitor C in the power factor compensator 164 and / or the power factor compensation by the compensation inductance L is performed. On the other hand, when the detected power factor θ is lower than the lower limit power factor θr−Δθ (S208: YES, S209: NO, S211), for example, when the inductance component of the single-phase load 20 increases or the capacitance component decreases, Compensation for increasing the power factor θ of the load 20 is performed, and the process returns to S200. Specifically, the power factor compensation by the compensation capacitor C and / or the power factor compensation by the compensation inductance L in the power factor compensator 164 is canceled.

  When it is determined that the detected power factor θ does not deviate from the power factor reference range (θr ± Δθ) (S208: NO), it is supplied to the single-phase load 20 from the load side terminals 16a and 16b by the tap switching transformer 140. The line voltage v of the two-phase voltages (P-phase voltage Vp, N-phase voltage Vn) is adjusted (S213). When the controller 162 determines that the detected line voltage v deviates from the line voltage reference range (vr ± Δv), the controller 162 taps the control signal SW3 for switching the tap of the primary winding of the transformer with tap. Output to the switch 144. When the detected line voltage v exceeds the upper limit line voltage (vr + Δv) (in the case of deviation from the upper limit) (S214: YES), the tap of the primary winding of the tapped transformer 142 is switched to change the tapped voltage. The secondary side voltage of the device 142 is lowered (S215), and the process returns to S200. On the other hand, when the detected line voltage v is lower than the lower limit line voltage (vr−Δv) (departure from the lower limit) (S214: NO, S216), the tap of the primary winding of the transformer 142 with tap is switched. The secondary side voltage of the transformer 142 with tap is increased (S215), and the process returns to S200.

=== Example of Operation of Two-Phase Selection Device ===
FIG. 3 is a waveform diagram for explaining an example of the two-phase selection operation by the two-phase selection device 120. It is assumed that time elapses in the order of periods Ta1, Tb1, Tc1, and Td1 shown in FIG.

  In the period Ta1, the two-phase selection device 120 selected one voltage line 12a and one neutral line 12b among the two voltage lines 12a and 12c and one neutral line 12b. State. That is, the single-phase load 20 is in a state where a voltage corresponding to the line voltage between the a-phase voltage Va of the voltage line 12a and the b-phase voltage Vb of the neutral line 12b is supplied.

  The a-phase voltage Va of the voltage line 12a is lower than the lower limit voltage (Vra−ΔV) and is in a state of deviating from the lower limit. The b-phase voltage Vb of the neutral wire 12b is in a state within the reference voltage range (Vrb ± ΔV). The c-phase voltage Vc of the voltage line 12c is within the reference voltage range (Vrc ± ΔV), but is higher than the reference voltage Vrc.

  In the period Tb1, the control unit 122 determines that the a-phase voltage Va of the voltage line 12a is out of the lower limit, and the c-phase voltage Vc of the voltage line 12c is within the reference voltage range, but the reference voltage range. It is determined that the voltage is higher than Vrc.

  In the period Tc1, the control unit 122 switches the voltage line 12a of the a-phase voltage Va currently selected by the voltage line selection unit 125 to the voltage line 12c of the c-phase voltage Vc that is not currently selected. As a result, since the load connected to the voltage line 12a on the power distribution system is reduced, the a-phase voltage Va of the voltage line 12a is increased and the lower limit deviation is eliminated. Further, since the load connected to the voltage line 12c increases on the distribution system, the c-phase voltage Vc of the voltage line 12c decreases and approaches the reference voltage Vrc.

  In the period Td1, one of the two voltage lines 12a and 12c and one neutral line 12b is switched to a state where one voltage line 12c and one neutral line 12b are selected. In other words, in the period Td1, the voltage corresponding to the line voltage between the c-phase voltage Vc of the voltage line 12c and the b-phase voltage Vb of the neutral line 12b is switched to a state where the single-phase load 2 is supplied.

  Even if the voltage of each phase becomes unbalanced due to the weight of the load connected to each phase of the three-phase AC distribution line, the two-phase voltage supplied to the single-phase load 20 by the above-described two-phase selection operation. Can be adjusted to fall within the voltage reference range. For this reason, the voltage supplied to the single-phase load 20 is stabilized, and the performance deterioration and malfunction of the single-phase load 20 can be prevented. In addition, one voltage line connected to a heavy load on the distribution system is switched to the other voltage line that is a light load on the distribution system and within the voltage reference range, or vice versa. If it sees as the whole system | strain, the imbalance of the load connected to each of the three phases of a three-phase alternating current distribution line can be eliminated.

=== Example of Operation of Power Factor Compensator ===
FIG. 4 is a waveform diagram for explaining an example of the power factor compensation operation by the power factor compensator 160. It is assumed that time elapses in the order of periods Ta2, Tb2, TC, Td2 shown in FIG.

  In the period Ta2, the power factor θ of the single-phase load 20 is lower than the lower limit power factor (θr−Δθ) due to an increase in the inductance component L of the single-phase load 20. Since the power factor θ is a delayed power factor that is lower than the lower limit power factor θr−Δθ, the two-phase line voltage (P-phase voltage Vp−N-phase voltage Vn) supplied to the single-phase load 20 ) Voltage drop occurs.

  In the period Tb2, the control unit 162 determines that the power factor θ of the single-phase load 20 is lower than the lower limit power factor (θr−Δθ). Then, the control unit 162 outputs a control signal SW2 that instructs the power factor compensator 164 to compensate for increasing (advancing) the power factor θ of the single-phase load 20.

  In the period TC, the power factor compensator 164 compensates for the capacitance component C for increasing (advancing) the power factor θ of the single-phase load 20, or for reducing the power factor θ (for delaying) the inductance component L. Cancel the compensation.

  In the period Td2, the power factor θ of the single-phase load 20 detected by the control unit 162 is increased (advanced) so that the power factor θ of the single-phase load 20 falls within the power factor reference range (θr ± Δθ). The lower limit deviation of the power factor θ of the single-phase load 20 is eliminated. Further, as the deviation from the lower limit of the power factor θ of the single-phase load 20 is eliminated, the two-phase line voltage (P-phase voltage Vp−N-phase voltage Vn) supplied to the single-phase load 20 increases.

  Even if the above-described two-phase selection operation is performed properly, the single-phase load 20 connected to the household voltage regulation system 100 (generally, it is often a motor load of a home appliance having an inductance component). .) Increases or decreases, the two-phase line voltage supplied to the single-phase load 20 may change based on the change in the power factor θ of the single-phase load 20 in some cases. However, by performing the power factor compensation operation after the two-phase selection operation, even if the two-phase line voltage based on the variation of the power factor θ of the single-phase load 20 varies, Can be converged to the reference line voltage range.

=== Example of operation of tap switching transformer ===
FIG. 5 is a waveform diagram for explaining an example of the tap switching operation by the tap switching transformer 140. It is assumed that time elapses in the order of periods Ta3, Tb3, Tc3, and Td3 shown in FIG.

  In the period Ta3, a voltage drop of the line voltage v (P phase voltage Vp−N phase voltage Vn) of the two-phase voltage supplied to the single-phase load 20 occurs, and the line voltage v is the lower limit line voltage (vr). -Δv).

  In the period Tb3, the controller 162 determines that the line voltage v is lower than the lower limit line voltage (vr−Δv). And the control part 162 outputs control signal SW3 which instruct | indicates the tap switching for raising the line voltage v with respect to the tap switching transformer 140. FIG.

  In the period Tc3, the tap switch 144 changes the turns ratio of the tapped transformer by switching the tap based on the control signal SW3 from the control unit 162, and increases the secondary voltage of the tapped transformer. .

  In the period td3, in response to the increase of the secondary voltage of the tapped transformer, the two-phase line voltage v falls within the reference line voltage range (vr ± Δv), and the lower limit deviation of the line voltage v is It will be resolved.

  With only the power factor compensation operation described above, it may be difficult to converge the two-phase line voltage to the reference line voltage range. Therefore, by performing the tap switching operation as an auxiliary voltage adjustment measure for the power factor compensation operation, it is possible to converge the two-phase line voltage within the reference line voltage range.

<<< Home voltage regulation system according to the second embodiment >>>
FIG. 6 is a diagram showing a configuration of a household voltage regulation system 200 according to the second embodiment of the present invention. The difference from the configuration of the domestic voltage regulation system 100 according to the first embodiment shown in FIG. 1 is that the two-phase selector 220 is provided on the utility pole including the pole transformer 224. It is. Below, it demonstrates centering on the point which is different from the structure of the household voltage regulation system 100. FIG.

  The two-phase selection device 220 includes one of the power receiving side terminals 22a, 22b, and 22c connected to the three-phase three-wire distribution lines 21a, 21b, and 21c installed on the power pole, and one of the transformers 242 of the tap switching transformer 240. It has connection terminals 24a and 24b for connecting to both terminals 26a and 26b of the next winding via single-phase two-wire distribution lines 25a and 25b.

  The two-phase selection device 220 includes a control unit 222, a pole transformer 224, and a two-phase selection unit 226. The control unit 222 has the same function as that of the control unit 122 except that the voltage of each phase of the three-phase three-wire distribution lines 21a, 21b, and 21c is used. The pole transformer 224 is a three-phase Δ-Δ (delta-delta) connection, and the voltage of the three-phase three-wire distribution lines 21a, 21b, and 21c is a single-phase three-wire type for the single-phase load 20. Convert (transform) to voltage. The pole transformer 224 may be a Y-Δ (star delta) connection. The two-phase selection unit 226 has the same function as that of the two-phase selection unit 124 except that the three-phase voltage on the secondary side of the pole transformer 224 is used.

  On the other hand, the tap switching transformer 240 provided on the home side is a single-phase two-wire distribution line 25a, 25b composed of one voltage line selected by the two-phase selection device 220 and one neutral line. Except that a two-phase voltage is applied, the function is the same as that of the tap switching transformer 140 shown in FIG. 1, and the power factor compensator 260 is the same as the function of the power factor compensator 160 shown in FIG. is there. In addition, as an alternative device for the home distribution board provided to each home, the two-phase selection device 220 is not provided, and thus the size and cost are reduced compared to the home voltage regulation system 100 shown in FIG. Can be realized.

  7 and 8 are flowcharts showing an overall operation flow of the household voltage regulation system 200. FIG. 2 differs from the overall operation flow of the home voltage regulation system 100 shown in FIG. 2 in that the two-phase selection operation (S700 to S706) is a two-phase selection device 220 provided on a power pole on the distribution system side. The power factor compensation operation and the tap switching operation (S800 to S812) are independently performed by the tap switching transformer 240 and the power factor compensation device 250 provided in each household on the load side. is there.

  In the two-phase selection operation (S700 to S706), when the control unit 222 determines that the selection is not possible (S702: NO), the state signal is sent to the control unit 262 of the power factor compensation device 260. Return to S700 without sending S. In addition, in the power factor compensation operation and the tap switching operation (S800 to S812), before the control unit 262 detects the power factor θ of the single-phase load 20 (S802), the two-phase voltage ( P-phase voltage Vp and N-phase voltage Vn) are detected (S800), and it is determined whether or not the two-phase voltages deviate from a predetermined voltage reference range (S801). That is, no distribution line such as a control line is required because the system-related control is not performed between the two-phase selection device 220, the tap switching transformer 240, and the power factor compensation device 260.

  According to the above-described home voltage regulation systems 100 and 200, the existing voltage fluctuations on the distribution system side are caused by the spread of private power generation facilities and the increase in power consumption of the single-phase load 20 in the future. Suppressing voltage fluctuations in each phase of the distribution line that is a three-phase alternating current, which is predicted to be difficult to deal with only by countermeasures (the voltage compensation device described above), and eventually each phase of the distribution line drawn into the inlet of each household The voltage fluctuation can be suppressed. In addition, the two-phase voltage supplied to the home single-phase load 20 can be converged to a predetermined voltage reference range, and the performance deterioration and malfunction of the home single-phase load 20 can be prevented.

  Although the best mode for carrying out the present invention has been described above, the above embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. . The present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are also included in the present invention.

It is the figure which showed the structure of the domestic voltage regulation system which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the flow of the whole operation | movement of the domestic voltage regulation system which concerns on the 1st Embodiment of this invention.

It is the figure which showed the structure.
It is a wave form chart for explaining an example of 2 phase selection operation by the 2 phase selection device concerning a 1st embodiment of the present invention. It is a wave form diagram for demonstrating an example of the power factor compensation operation | movement by the power factor compensator which concerns on the 1st Embodiment of this invention. It is a wave form chart for explaining an example of the tap change operation by the tap change transformer concerning a 1st embodiment of the present invention. It is the figure which showed the structure of the domestic voltage regulation system which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the flow of the whole operation | movement of the domestic voltage regulation system which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the flow of the whole operation | movement of the domestic voltage regulation system which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

10 Inlet 20 Single phase load 100, 200 Domestic voltage regulation system 120, 220 Two phase selection device 122, 222 Control unit 124, 226 Two phase selection unit 125, 227 Voltage line selection unit 126, 228 Neutral line selection unit 140 , 240 Tap change transformer 142, 242 Tap transformer 144, 244 Tap changer 160, 260 Power factor compensator 162, 262 Control unit 164, 264 Power factor compensator

Claims (11)

Of the three distribution lines drawn into the home with one neutral line and two voltage lines, the one neutral line and one voltage line of the two voltage lines A voltage regulation system for home use that supplies a two-phase voltage to a single-phase load of the household and regulates the two-phase voltage,
A two-phase selection device that selects one voltage line from the two voltage lines that supply a two-phase voltage to the single-phase load together with the one neutral line, the two-phase selection device,
A voltage detector for detecting each voltage of the two voltage lines;
A voltage determination unit that determines whether each voltage of the two voltage lines detected by the voltage detection unit deviates from a predetermined voltage reference range;
Based on the determination result of the voltage determination unit, one voltage line that does not deviate from the voltage reference range from the two voltage lines that supply a two-phase voltage to the single-phase load together with the one neutral line. A voltage line selector for selecting a voltage line;
A voltage regulation system for home use characterized by comprising: The household voltage regulation system according to claim 1,
The voltage line selector is
Based on the determination result of the voltage determination unit, one of the two voltage lines selected is out of the voltage reference range, and the two voltage lines that are not selected. If the other voltage line does not deviate from the voltage reference range, switching the one voltage line to the other voltage line,
A voltage regulation system for home use. The household voltage regulation system according to claim 1 or 2,
A power factor compensation device that compensates the power factor of the single phase load between the selection device and the single phase load, the power factor compensation device,
A power factor detector that detects a power factor of the single-phase load based on two-phase voltage and current supplied to the single-phase load;
A power factor determination unit that determines whether or not the power factor detected by the power factor detection unit deviates from a predetermined power factor reference range;
When it is determined by the power factor determination unit that the power factor detected by the power factor detection unit deviates from the power factor reference range, the difference between the upper and lower limits defining the power factor reference range and the detected power factor A power factor compensator for compensating
A voltage regulation system for home use characterized by comprising: It is a household voltage regulation system of Claim 3, Comprising:
The power factor detector is
When each voltage of the two voltage lines detected by the voltage detection unit based on the determination result of the voltage determination unit deviates from the voltage reference range, the power factor of the single-phase load is detected.
A voltage regulation system for home use. The household voltage regulation system according to claim 3 or 4 ,
A tap switching transformer between the two-phase selection device and the power factor compensation device;
The power factor compensator is:
A line voltage detector for detecting a line voltage of the two-phase voltage supplied to the single-phase load;
A line voltage determination unit that determines whether or not the line voltage detected by the line voltage detection unit deviates from a predetermined line voltage reference range;
When it is determined by the line voltage determination unit that the line voltage detected by the line voltage detection unit deviates from the line voltage reference range, the upper and lower limits that determine the line voltage reference range are detected. A tap switching control unit that switches the tap of the tap switching transformer according to the difference with the line voltage;
A voltage regulation system for home use characterized by comprising: 6. The household voltage regulation system according to claim 5 , wherein the two-phase selection device, the tap switching transformer, and the power factor compensation device are configured as a single-phase three-wire distribution line of a three-phase AC installed on a power pole. A voltage regulation system for home use, characterized in that the system is provided between a household service port that is drawn in by a power distribution line and a single-phase load of the household.   The household voltage regulation system according to claim 6, wherein the two-phase selection device, the tap switching transformer, and the power factor compensation device are mounted on an integrated device. Adjustment system.   8. The household voltage regulation system according to claim 7, wherein the integrated device is a household distribution board. The household voltage regulation system according to claim 5 ,
The two-phase selection device is provided on a power pole for installing a three-phase AC distribution line,
The tap switching transformer and the power factor compensator are housed in by a single-phase two-wire distribution line composed of one voltage line and one neutral line selected by the two-phase selection device. Provided between the mouth and the single-phase load of the household,
A voltage regulation system for home use.   10. The domestic voltage regulation system according to claim 9, wherein the tap change transformer and the power factor compensation device are mounted on an integrated device.   11. The household voltage regulation system according to claim 10, wherein the integrated device is a household distribution board.