JP2005348562A - Ac power supply apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cancel a high frequency component generated by a phase control of a semiconductor control element and improve a waveform of an AC input current in an AC power supply apparatus. <P>SOLUTION: A power supplying controller 3 comprises thyristors S1, S2 and is connected between AC input terminals 1a, 1b and AC output terminals 2a, 2b connected to a load 4. A compensation current supplying circuit 6 is connected at the preceding stage of the power supplying controller 3. A control signal from a power converting circuit included in the compensation current supplying circuit 6 is formed on the basis of phase control signals of the thyristors S1, S2. The compensation current supplying circuit 6 flows a current for compensating a waveform distortion generated by the phase control of the thyristors S1, S2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a single-phase or three-phase or multi-phase AC power supply device having a harmonic current suppression function suitable for a constant current power supply device for aerial lighting or a similar power supply device.

  The constant current power supply device for aviation lighting is connected to an anti-parallel circuit of a thyristor between an AC input terminal and a step-up transformer, as shown in Patent Document 1, for example, and is connected to the secondary side of the step-up transformer. An aerial lighting lamp is connected, and the load current is adjusted by phase control of the thyristor.

  In the above-described constant current power supply device for aeronautical lighting or a similar power supply device, a thyristor capable of phase control is used, so that a relatively large current can flow and a power loss is relatively small. Therefore, there is a disadvantage that harmonic current is included in the current waveform. When a harmonic current is included in the current waveform, the power factor is degraded, and the power capacity of a power source such as a generator to which an AC power supply device including a thyristor is connected is inevitably increased. In addition, there is a possibility of causing harmonic disturbance or noise disturbance to another load connected to the AC power supply.

Connecting a compensation current supply circuit to an AC input line in order to improve the waveform and power factor of the AC power supply current is well known in Japanese Patent Application Laid-Open No. 2004-228, etc. However, it is not disclosed that harmonic suppression in an AC power supply device including a phase-controllable semiconductor control element is achieved with a relatively simple circuit configuration.
JP 58-18897 A JP 10-333761 A

  Therefore, the problem to be solved by the present invention is that an AC input current waveform includes a relatively large harmonic component in an AC power supply apparatus including a phase-controllable semiconductor control element. Another problem of the present invention is that it is difficult to suppress harmonic components easily and satisfactorily. Yet another object of the present invention is that if a single-phase load is connected to a three-phase AC power source, an unbalance of the three-phase AC current occurs.

In order to solve the above problems, the present invention provides an AC input end, an AC output end to which a load is connected, and a current or voltage of the AC output end connected between the AC input end and the AC output end. A power supply controller including a phase-controllable semiconductor control element that controls both of them, a phase control circuit that forms a phase control signal of the semiconductor control element and sends it to the semiconductor control element, and the semiconductor control A pulse width modulation type power conversion circuit capable of supplying a compensation current for improving distortion of a current waveform caused by phase control of an element and connected to the AC input terminal and supplying a compensation current And a power conversion control means for controlling on / off of a switch included in the power conversion circuit. Than it is.
In addition, the said AC input terminal in this invention means an AC input terminal or an AC input supply part. The AC output terminal means an AC output terminal or a portion to which a load or an output stage circuit is connected.

In addition, as shown in claim 2, the power conversion control means includes a load state detection means for detecting the current or voltage of the AC output terminal or both, and a reference synchronized with the AC voltage of the AC input terminal. Reference sine wave generation means for generating a sine wave, connected to the phase control circuit, the load state detection means, and the reference sine wave generation means, the phase control signal, the output of the load state detection means, and the reference sine A target compensation current waveform forming means for forming a target compensation current waveform based on the wave, and a switch on / off for supplying a compensation current corresponding to the target compensation current waveform connected to the target compensation current waveform forming means It is desirable to comprise a control signal forming means for forming a control signal and controlling the switch by the switch on / off control signal.
According to a third aspect of the present invention, the target compensation current waveform forming means is connected to the phase control circuit and the load state detection means, and is based on the phase control signal and the output of the load state detection means. Current waveform estimating means for theoretically estimating the waveform of the current flowing through the output end and outputting an estimated current waveform; obtained from the reference sine wave obtained from the reference sine wave generating means and the current waveform estimating means It is desirable to comprise subtracting means for forming a target compensation current waveform corresponding to the difference from the estimated current waveform.
According to a fourth aspect of the present invention, the current waveform estimation means is connected to the phase control circuit and the reference sine wave generation means, and extracts a portion corresponding to the conduction period of the phase control signal of the reference sine wave. Extracting means, and load amount detecting or calculating means connected to the load state detecting means for detecting or calculating a load amount indicating an effective value or average value of the current or voltage or power of the AC output terminal, It is desirable to have correction means for correcting the amplitude of the waveform extracted by the extraction means by a signal indicating the load quantity obtained from the load quantity detection or calculation means and outputting an estimated current waveform.
The target compensation current waveform forming means corresponds to a period in which the phase control signal indicates a non-conduction period from the reference sine wave obtained from the reference sine wave generating means. An extraction means for extracting a portion; and an amplitude of the reference sine wave before or after extracting the reference sine wave by the extraction means so as to correspond to an output of the load condition detection means. It is desirable to comprise correction means for correcting based on the output.
According to a sixth aspect of the present invention, the phase control circuit is detected by a reference value generating unit that generates a signal indicating a reference value of the current, voltage, or power of the AC output terminal, and the load state detecting unit. It is desirable to comprise phase control signal forming means for forming a phase control signal of the semiconductor control element so that a signal indicating a load state matches the reference value.
According to a seventh aspect of the present invention, the compensation current supply circuit includes an AC terminal connected to the AC input terminal for supplying a compensation current, a pair of DC terminals, the AC terminal, and the pair of DCs. A pulse width modulation type power conversion circuit comprising a plurality of semiconductor switches bridged between the terminals and a plurality of individual or parasitic diodes connected in reverse parallel to the plurality of semiconductor switches, respectively. A smoothing capacitor connected between the DC terminals, an inductor connected in series with a current path between the AC terminal and the power conversion circuit, and a plurality of currents between the AC terminal and the power conversion circuit It is desirable to have a filter capacitor connected between the passages.
Further, as shown in claim 8, further, a DC voltage detection circuit for detecting a voltage between the pair of DC terminals, a reference voltage source for generating a reference voltage indicating a target voltage between the pair of DC terminals, A DC feedback control signal forming circuit for forming a DC feedback control signal indicating a difference between an output of the DC voltage detection circuit and the reference voltage; and an amplitude of the reference sine wave or the target compensation current waveform by the DC feedback control signal. It is desirable to have correction means for correcting.
The target compensation current waveform forming means subtracts the estimated current waveform estimated by the current waveform estimating means from the reference sine wave or a reference sine wave corrected by the DC feedback control signal. First subtracting means, input current detecting means for detecting an input current flowing through the AC input terminal, and the input current detecting means from the reference sine wave or the reference sine wave corrected by the DC feedback control signal It is desirable to have second subtracting means for forming an error signal with respect to the output of the first subtracting means, and means for correcting the output of the first subtracting means with the error signal obtained from the second subtracting means. .
Further, according to a tenth aspect of the present invention, the target compensation current waveform forming unit is further configured to detect or calculate a load amount indicating an effective value or an average value of the current, voltage, or power of the AC output terminal. Load amount detection or calculation means connected to the state detection means, wherein the correction means determines the amplitude of the reference sine wave or the reference sine wave corrected by the DC feedback control signal of the load amount detection or calculation means. A means for modulating based on an output, wherein the extracting means corresponds to a period in which the phase control signal indicates non-conduction from the reference sine wave, the corrected reference sine wave, or the modulated reference sine wave; The target compensation current waveform forming means further includes an input current detection means for detecting an input current flowing through the AC input terminal, and the reference sine wave or the corrected Subtracting means for forming an error signal between the quasi-sine wave or the modulated reference sine wave and the output of the input current detecting means; means for correcting the output of the extracting means with the error signal obtained from the subtracting means; It is desirable to have
The load connected to the AC output terminal is a circuit including an aerial lighting lamp, the semiconductor control element is a thyristor, and the phase control circuit is fixed to the load. It is desirable that the circuit controls the phase control angle of the thyristor so as to supply current.
In addition, as shown in claim 12, the AC input terminal is a first, second and third AC input terminal for supplying a three-phase AC voltage, and the AC output terminal connects at least one single-phase load. The power conversion circuit is preferably a three-phase power conversion circuit.
Furthermore, as shown in claim 13, a single-phase load is provided between the first, second and third AC input terminals for supplying a sinusoidal three-phase AC voltage, and the first and second AC input terminals. A power supply controller including a phase-controllable semiconductor control element connected through a circuit and controlling a load current or voltage or both, and forming the phase control signal of the semiconductor control element to control the semiconductor A phase control circuit to be sent to the element; and a current waveform connected to the first, second and third AC input ends and flowing through the first, second and third AC input ends, and current balance It is desirable to configure the AC power supply apparatus with a three-phase compensation current supply circuit having a function of supplying a compensation current for improvement.

According to the invention of each claim, the harmonic component generated by the phase control of the semiconductor control element can be canceled to improve the waveform of the AC input current in the AC power supply apparatus.
Further, according to the inventions of claims 2 to 11, waveform improvement, that is, suppression of harmonic current can be achieved easily and satisfactorily. In other words, since the target compensation current waveform is formed using the phase control signal of the semiconductor control element such as a thyristor, the target compensation current waveform can be formed without any delay in detecting the current or voltage. The current waveform can be obtained easily and satisfactorily or accurately.
According to the invention of claim 7, the compensation current can be easily supplied by the power conversion circuit.
According to the invention of claim 8, it is possible to suppress an increase in the voltage between the DC terminals of the pair of power conversion circuits.
According to the inventions of claims 9 and 10, the accuracy of the target compensation current waveform can be increased.
According to the invention of claim 11, a constant current can be easily supplied to the load including the aerial lighting lamp by the phase control of the thyristor.
Further, according to the inventions of claims 12 and 13, an improvement in the unbalance of the three-phase alternating current can be easily achieved.

  Next, an embodiment of the present invention will be described with reference to FIGS.

  The AC power supply for aerial lighting according to the first embodiment shown in FIG. 1 includes first, second and third AC input terminals 1a, 1b, 1c as AC input terminals connected to a commercial three-phase AC power source, First and second AC output terminals 2a and 2b, which can also be called AC output terminals, and first and second semiconductor control elements capable of phase control for controlling the current, voltage or power of the load Power supply controller 3 comprising an antiparallel connection circuit of thyristors S1 and S2, a load 4 including an aerial lighting lamp, a phase control circuit 5, a compensation current supply circuit 6, a power conversion control circuit 7, and a load state A load current detector 8 as detection means and first, second and third AC input current detectors 9a, 9b, 9c are provided.

  The power supply controller 3 composed of the antiparallel connection of the first and second thyristors S1 and S2 can also be called a current controller or voltage controller or current and voltage controller or power controller or power converter. The first AC input terminal 1a and the first AC output terminal 2a are connected in series to a line 12a. In this embodiment, the second AC input terminal 1b and the second AC output terminal 2b are connected by a line 12b without using a power controller. Further, the load 4 is not connected to the third AC input terminal 1c.

  The load 4 is a single-phase load, and is connected to an output transformer 40 having a step-up configuration having primary and secondary windings N1 and N2 electromagnetically coupled to each other, and output terminals 2a ′ and 2b ′ of the transformer 40. Lamp load circuit 4 '. The primary winding N1 of the output transformer 40 is connected between the first and second AC output terminals 2a and 2b. In FIG. 1, since the load 4 is connected between the first and second AC input terminals 1a and 1b via the power supply controller 3, the first, second and third AC input terminals 1a, 1b and 1c are connected. In contrast, a three-phase unbalanced load is connected. Of course, another load is connected to one or both of the second and third AC input terminals 1b and 1c and between the first and third AC input terminals 1a and 1c via or without a power supply controller. can do.

  The lamp load circuit 4 ′ connected to the output terminals 2a ′ and 2b ′ of the secondary winding N2 of the transformer 40 includes a plurality of load transformers 41a and 41b and a plurality of lamps 42a and 42b. The primary windings of the plurality of load transformers 41a and 41b are connected in series to each other and to the secondary winding N2 of the output transformer 40. The illumination lamps 42a and 42b are connected to the secondary windings of the load transformers 41a and 41b. The output terminals 2a ′ and 2b ′ of the transformer 40 can also be called AC output terminals.

  The phase control circuit 5 supplies a phase control signal to the control terminals (gates) of the first and second thyristors S1 and S2. The load current detector 8 and the power supply line 12a are used to form the phase control signal. , 12b. Details of the thyristor control circuit 5 will be described later.

  Compensation current supply circuit 6, which can also be called a bidirectional power conversion circuit, supplies a compensation current for improving the waveform, and is a well-known pulse width modulation type power capable of bidirectional power conversion with LC circuit 61. The converter circuit 62 and the smoothing capacitor 63 are connected to the main circuit including the power supply controller 3 and the load 4 in parallel. That is, the main circuit composed of the power supply controller 3 and the load 4 is connected to the first and second AC input terminals 1a and 1b, and the first and second compensation current supply circuits 6 can be called branch conductors. The second and third AC side lines 64a, 64b and 64c are connected to the first, second and third AC input terminals 1a, 1b and 1c. More specifically, the first and second AC side lines 64a and 64b of the power conversion circuit 62 are connected to the first and second power supply lines 12a and 12b of the main circuit at the first and second connection points P1 and P2, respectively. It is connected. The first connection point P1 is set between the first AC input terminal 1a and the power supply controller 3. The second connection point P2 is set between the second AC input terminal 1b and the second AC output terminal 2b. The third AC side line 64c of the power conversion circuit 62 is connected to the third AC input terminal 1c. The LC circuit 61 includes first, second and third filter capacitors C1, C2 and C3 and first, second and third inductors L1, L2 and L3. The first, second, and third filter capacitors C1, C2, and C3 remove high frequency components (for example, 20 to 100 kHz) based on on / off of switches included in the power conversion circuit 62. Thus, the power conversion circuit 62 is connected between the first, second and third AC side lines 64 a, 64 b and 64 c and has a capacity sufficiently smaller than that of the smoothing capacitor 63. The first, second, and third inductors L1, L2, and L3 have both a high-frequency component removal function and a boost reactor function, and the first, second, and third AC sides of the power conversion circuit 62 The lines 64a, 64b, and 64c are connected in series. A smoothing capacitor 63 made of an electrolytic capacitor is connected between the DC side lines 65 a and 65 b as the pair of DC terminals of the power conversion circuit 62. Details of the power conversion circuit 62 will be described later.

A load current detector 8 as a load state detecting means detects a load current before compensation passing through the power supply controller 3 and the first AC output terminal 2a, and is connected to the first connection point P1 and the first AC output. It arrange | positions along the line between the ends 2a. The load current detector 8 can be arranged along the output line of the secondary winding N2 of the output transformer 40 as shown by a dotted line in FIG. This load current detector 8 can be constituted by a CT or a Hall IC, and is connected to the phase control circuit 5 by a line 81. The load current detector 8 can be connected to the power conversion control circuit 7 by a line 82 indicated by a dotted line instead of the line 51a described later. When the load voltage is controlled to be constant by the power supply controller 3, a circuit for detecting the voltage between the first and second AC output terminals 2a and 2b or the voltage in the load 4 instead of the load current detector 8. In addition, when the power supply controller 3 controls the load power to be constant, a circuit for detecting the load power is provided instead of the load current detector 8.

  The first and second input current detectors 9a and 9b are arranged along a line between the first and second AC input terminals 1a and 1b and the interconnection points P1 and P2, and are used for third input current detection. The device 9c is arranged along a line from the third AC input terminal 1c to the power conversion circuit 62. Accordingly, the first, second and third input current detectors 9a, 9b and 9c detect the compensated AC input current passing through the first, second and third AC input terminals 1a, 1b and 1c.

The power conversion control circuit 7 is for controlling the power conversion circuit 62 in the compensation current supply circuit 6 so that a desired compensation current can be supplied. In addition to being connected to the circuit 62, the line 82 is connected to the load current detector 8, and the lines 91, 92, 93 are connected to the first, second and third input current detectors 9a, 9b, 9c. Connected to the phase control circuit 5 by a line 94, connected to the first, second and third AC input terminals 1a, 1b, 1c by lines 95, 96, 97, and a smoothing capacitor by lines 98, 99. 63. Details of the power conversion control circuit 7 will be described later.
The power conversion control means for controlling on / off of the switch included in the power conversion circuit 62 so as to supply a desired compensation current includes the power conversion control circuit 7, the load current detector 8, and the first and second. And a combination of the third input current detectors 9a, 9b, and 9c.

  As shown in detail in FIG. 2, the power conversion circuit 62 of FIG. 1 includes first, second, third, fourth, fifth and sixth diodes D1, D2, D3, D4, First, second, third, fourth, fifth and sixth switches as conversion switches connected in reverse direction parallel to D5 and D6 and first to sixth diodes D1 to D6, respectively. Q1, Q2, Q3, Q4, Q5 and Q6. Although the first to sixth switches Q1 to Q6 are shown as insulated gate bipolar transistors or IGBTs in FIG. 2, they can be replaced by other controllable semiconductor switches such as FETs and transistors. Further, instead of configuring the first to sixth diodes D1 to D6 as individual diodes, the first to sixth switches Q1 to Q6 can be built-in, that is, parasitic diodes.

  The control terminals (gates) of the first to sixth switches Q1 to Q6 are connected to the power conversion control circuit 7 of FIG. 1 through lines not shown. More specifically, the control terminals of the first to sixth switches Q1 to Q6 are connected to lines for supplying the first to sixth control signals G1 to G6 of the power conversion control circuit 7 shown in detail in FIG. . The interconnection points of the first and second diodes D1 and D2 of the power conversion circuit 62, the interconnection points of the third and fourth diodes D3 and D4, and the interconnection points of the fifth and sixth diodes D5 and D6 are as follows. , First, second, and third AC side lines 64a, 64b, 64c, first, second, and third AC input terminals via first, second, and third inductors L1, L2, L3, etc. 1a, 1b, 1c. The cathodes of the first, third, and fifth diodes D1, D3, and D5 are connected to one DC side line 65a, and the anodes of the second, fourth, and sixth diodes D2, D4, and D6 are the other DC side. It is connected to the line 65b. The power conversion circuit 62 is a switching circuit capable of both a known AC-DC conversion operation and a DC-AC conversion operation.

  As shown in detail in FIG. 3, the phase control circuit 5 in FIG. 1 is a well-known circuit for forming the phase control signal Vg1 of the first and second thyristors S1 and S2, and includes a current detection circuit 51, an error amplifier 52, and the like. It comprises a reference voltage source 53, a sawtooth generation circuit 54 and a comparator 55.

  The current detection circuit 51 is current detection means for obtaining a current detection signal Vi indicating an effective value of the load current I1, and is connected to the load current detector 8 by a line 81, and is connected to the power supply controller 3 and the first AC output. A current detection signal Vi comprising a DC voltage corresponding to the effective value of the load current I1 flowing through the end 2a is output. The current detection circuit 51 can also be formed so as to output a signal indicating the average value of the load current I1. Further, when the load current detector 8 outputs a signal indicating the effective value or average value of the load current I1, the current detection circuit 51 can be omitted. The current detection circuit 51 is connected to the error amplifier 52 and is also connected to the power conversion control circuit 7 through a line 51a. Therefore, the current detection circuit 51 is also used as a current amount detection or calculation means in the power conversion control circuit 7. It is also possible to provide the current detection circuit 51 in the power conversion control circuit 7, obtain the current detection signal Vi from the power conversion control circuit 7, and send it to the comparator 52. When the power supply controller 3 controls the load voltage, the effective value or average value of the voltage between the first and second AC output terminals 2 a and 2 b or the voltage in the load 4 instead of the current detection circuit 51. A voltage detection circuit is provided to output a DC signal indicating. In addition, when the load power is controlled by the power supply controller 3, a power detection circuit that outputs a DC signal indicating an effective value or an average value of the load power is provided instead of the current detection circuit 51.

  One input terminal of the error amplifier 52 is connected to the current detection circuit 51, and the other input terminal is connected to a reference voltage source 53 that supplies a reference voltage indicating a desired load current. Accordingly, the error amplifier 52 outputs an error signal Ve indicating the difference between the current detection signal Vi and the reference voltage.

  The sawtooth wave generation circuit 54 is connected to the first and second AC input terminals 1a and 1b via lines 56 and 57, and is synchronized with the sine wave AC input voltage Va composed of the first phase voltage shown in FIG. Then, the sawtooth voltage Vt is generated as shown in FIG. 6B with a period of 1/2 (for example, 10 ms). The lines 56 and 57 are connected to the reference sine wave generating means 70 shown in FIG. 4 instead of being connected to the first and second AC input terminals 1a and 1b, and the sawtooth voltage Vt of the sawtooth generating circuit 54 is shown in FIG. It can be formed based on the output of the reference sine wave generating means 70. Further, a triangular wave voltage can be used instead of the sawtooth voltage Vt.

  One output terminal of the comparator 55 is connected to the error amplifier 52, and the other input terminal is connected to the sawtooth wave generation circuit 54. Therefore, the comparator 55 compares the sawtooth voltage Vt and the error signal Ve as shown in FIG. 6B, and forms a phase control signal Vg1 composed of a binary signal shown in FIG. 6C. The phase control signal Vg1 is sent to the gate terminals of the first and second thyristors S1 and S2 of FIG. It is also sent to the circuit 7.

  As shown in detail in FIG. 4, the power conversion control circuit 7 includes a reference sine wave generating means 70, a DC feedback control signal forming circuit 71, and first, second and third phase control circuits 72a, 72b and 72c. . The first, second and third phase control circuits 72a, 72b and 72c are substantially the same except that they operate based on a three-phase reference sine wave having a phase difference of 120 degrees from each other. 4, only the first phase control circuit 72a is shown in detail, and the second and third phase control circuits 72b and 72c are shown as blocks.

  The reference sine wave generating means 70 is connected to the first, second and third AC input terminals 1a, 1b and 1c of FIG. 1 by lines 95, 96 and 97, and the first, second and third AC inputs. First, second and third phase AC input voltages Va, Vb and Vc at terminals 1a, 1b and 1c are detected, and first, second and third phase AC input voltages Va, Vb and Vc corresponding to the first, second and third phase AC input voltages Va, Vb and Vc are detected. 1, 2 and 3 phase reference sine wave voltages Va, Vb, Vc are generated on lines 70a, 70b, 70c. Here, for ease of explanation, the first, second and third phase AC input voltages at the first, second and third AC input terminals 1a, 1b and 1c and the reference sine wave generating means 70 of FIG. Both the output first, second and third phase reference sine wave voltages are denoted by the same Va, Vb and Vc. For example, the first, second and third phase reference sine wave voltages Va, Vb and Vc of 50 Hz have a phase difference of 120 degrees from each other as shown in FIG. It is supplied to the control circuits 72a, 72b, 72c. The first, second and third phase reference sine wave voltages Va, Vb and Vc are used as the first, second and third phase alternating currents at the first, second and third AC input terminals 1a, 1b and 1c. It can also be called a target reference waveform of the input currents Ia, Ib, and Ic.

  The DC feedback control signal forming circuit 71 includes a DC voltage detection circuit 71a connected to the smoothing capacitor 63 of FIG. 1 by lines 98 and 99, a reference voltage source 71b for generating a reference voltage indicating a desired DC voltage, and a DC voltage. It comprises an error amplifier 71c connected to the detection circuit 71a and the reference voltage source 71b, and a proportional integration circuit 71d connected to the error amplifier 71c. A signal indicating the difference between the DC voltage detection signal obtained from the error amplifier 71c and the reference voltage is smoothed by the proportional integration circuit 71d and then sent to the first, second and third phase control circuits 72a, 72b and 72c, Used for reference sine wave correction.

  The correction means 76 of FIG. 4 can also be called a DC voltage correction means or a reference sine wave amplitude modulation means. The DC voltage between the DC side lines 65a and 65b functioning as the DC terminal of the power conversion circuit 62 is predetermined. It has a function for maintaining the value, and is connected to the reference sine wave generating means 70 and the DC feedback control signal forming circuit 71. For example, as shown in FIG. 5, the amplitude of the first phase reference sine wave voltage Va is modulated. It is comprised with the multiplier for doing. Therefore, the correcting means 76 multiplies the first phase reference sine wave voltage Va by the DC feedback control signal V71 and outputs the amplitude-modulated first phase reference sine wave voltage Va '. Since the first-phase reference sine wave voltages Va and Va ′ before and after the correction indicate the target current flowing through the first AC input terminal 1a, these can also be called target current command signals. If correction of the DC voltage is not required, the DC feedback control signal forming circuit 71 and the correction means 76 can be omitted.

  The first phase control circuit 72a outputs the output of the reference sine wave generating means 70, the output of the DC feedback control signal forming circuit 71, the phase signal Vg1 of the line 94, the output Vi of the current detection circuit 51 of the line 51a, and the first of the line 91. Based on the phase alternating current input current Ia, first and second control signals G1 and G2 for supplying a desired compensation current are formed. In FIG. 4, the first phase control circuit 72 a is shown as a load current waveform estimating unit 73, a correcting unit 76, a target compensation current waveform forming unit 77, and a control signal forming unit 78. However, the portion excluding the control signal forming means 78 from the first phase control circuit 72a can also be called target compensation current waveform forming means.

  The load current waveform estimating unit 73 includes an extracting unit 73 ′ and a correcting unit 75. The extracting means 73 'can also be called a load current reference waveform estimating means, and is provided to easily and accurately supply a desired compensation current. The extraction means 73 'is connected to the phase control circuit 5 by a line 94 and to the correction means 76 by a line 74, and the phase control signal Vg1 on the line 94 is connected to the first and second thyristors S1 and S2. The first-phase reference sine wave voltage Va ′ after correction is extracted only during the period indicated by. For example, as shown schematically in FIG. 5, the extraction means 73 ′ connects a signal extraction switch SW composed of a semiconductor switch or the like in series to a line 74, and a line 94 of the phase control signal Vg1 is connected to the control terminal of the extraction switch SW. It can be configured by connecting. The extraction switch SW outputs the phase control signal Vg1 shown in FIG. 6C in the corrected first phase reference sine wave voltage Va ′ having a waveform similar to the first phase reference sine wave voltage Va in FIG. Only the portions of the conduction periods t1 to t2 and t3 to t4 are extracted, and a load current estimation reference waveform signal V73 ′ that can be called a load current theoretical waveform shown in FIG. The load current estimation reference waveform signal V73 'does not necessarily match the actual load current I1 waveform shown in FIG. Although the waveform of the actual load current I1 in FIG. 6D has a delay with respect to the phase control signal Vg1 in FIG. 6C, the load current estimation reference waveform signal V73 ′ in FIG. There is substantially no delay with respect to the phase control signal Vg1. When the target compensation current is determined by using the load current estimation reference waveform signal V73 'having substantially no delay according to this embodiment, the detection response delay of the target compensation current is improved. In FIG. 4, the line 74 is connected to the output terminal of the correcting means 76. Instead, it is connected to the reference sine wave generating means 70 as shown by the dotted line in FIGS. 4 and 5, and the first phase before correction is made. The reference sine wave voltage Va can be sent to the extraction means 73 ′.

  The amplitude of the load current estimation reference waveform signal V73 'obtained from the extraction means 73' is not necessarily accurate. If the load 4 is fixed and the load current I1 is also fixed, the amplitude of the load current estimation reference waveform signal V73 'can be estimated accurately. However, since the load 4 actually fluctuates, in order to execute correction of the load current estimation reference waveform signal V73 ′ with respect to the fluctuation of the load 4, or to adjust the amplitude of the load current estimation reference waveform signal V73 ′ to a desired value. Correction means 75 is connected to extraction means 73 ′. The correcting means 75 includes an amplitude adjustment signal forming circuit 75a and a multiplier 75b.

The amplitude adjustment signal forming circuit 75a is connected to the current detection circuit 51 of FIG. 3 by a line 51a. The amplitude adjustment signal forming circuit 75a outputs an amplitude adjustment value a for correcting the amplitude of the load current estimation reference waveform signal V73 'so as to coincide with the actual amplitude of the load current I1. That is, the amplitude adjustment signal forming circuit 75a determines a coefficient K for correcting the amplitude of the load current estimation reference waveform signal V73 ′ so as to match the amplitude of the target compensation current, and uses this coefficient K as the current detection of the line 51a. The amplitude adjustment value a is determined by multiplying the signal Vi. In this embodiment, the current detection circuit 51 is included in the phase control circuit 5 of FIG. 3. However, as described above, the current detection circuit 51 can be included in the correction means 75, and the current detection circuit 51 and the amplitude adjustment signal are included. Together with the forming circuit 75a, it can also be called current amount detection or calculation means for detecting or calculating a current amount indicating an effective value or an average value of the current flowing through the AC output terminals 2a and 2b. The amplitude adjustment signal forming circuit 75a is connected to the load current detector 8 via the current detection circuit 51. However, when the fluctuation of the load current can be ignored, the load is detected from the circuit constant of the main circuit instead of the load current detector 8. Load current estimation means for estimating the current can be provided, and current amount calculation means for calculating the current amount from the output of the load current estimation means can be provided instead of the current detection circuit 51. Further, the current detection circuit 51 and the amplitude adjustment signal forming circuit 75a can be configured integrally.

  The multiplier 75b multiplies the load current estimation reference waveform signal V73 ′ obtained from the extraction means 73 ′ by the amplitude adjustment value a obtained from the amplitude adjustment signal forming circuit 75a, and the corrected load current consisting of V73 ′ × a. The estimated waveform signal V75 is output as shown in FIG. The corrected load current estimated waveform signal V75 has the same waveform as the estimated waveform signal V73 'before correction shown in FIG.

  The target compensation current waveform forming unit 77 in FIG. 4 is connected to the correction unit 76, the multiplier 75b, and the first phase input current detection line 91, and creates the target compensation current waveform V77 shown in FIG. The target compensation current waveform V77 in FIG. 6 (I) is obtained from the first phase reference sine wave voltage Va ′ after the first phase reference sine wave voltage Va in FIG. This substantially corresponds to the waveform obtained by subtracting the estimated waveform signal V75 obtained by the multiplier 75b.

  The target compensation current waveform forming means 77 of this embodiment comprises first and second subtracters 101 and 102 and a correction circuit 103 as shown in detail in FIG. One input terminal of the first subtractor 101 is connected to the correcting means 76 that outputs the first phase reference sine wave voltage Va ', and the other input terminal is connected to the multiplier 75b for correcting the load current estimation waveform. Yes. If it is not necessary to provide the correcting means 76 and the multiplier 75b, one input terminal of the first subtractor 101 is connected to the reference sine wave generating means 70, and the other input terminal is connected to the extracting means 73 ′. Connecting. The first subtracter 101 uses the corrected first phase reference sine wave voltage Va 'similar to the reference sine wave voltage Va in FIG. 6A to the corrected load current estimation waveform signal V75 in FIG. 6F. Is subtracted to output the target compensation current waveform signal V101 shown in FIG. The target compensation current supply control can be executed only with the target compensation current waveform signal V101. However, in the embodiment of FIG. 5, the second subtractor 102 is provided to further increase the compensation accuracy, and the output of the first subtractor 101 is corrected by this output.

  One input terminal of the second subtractor 102 is connected to the correction means 76, and the other input terminal is connected to the current detector 9 a of FIG. 1 via the first phase AC input current detection line 91, and the correction means 76. An error signal V102 shown in FIG. 6 (H) having a value obtained by subtracting a signal corresponding to the first phase AC input current Ia from the corrected reference sine wave voltage Va 'corresponding to the target AC input current command value obtained from Output.

  The correction circuit 103 is composed of an addition circuit, and has first, second, third and fourth resistors R1, R2, R3, R4 and an operational amplifier A1. The output terminals of the first and second subtracters 101 and 102 are connected to one input terminal of the operational amplifier A1 through first and second resistors R1 and R2, respectively. The third resistor R3 is connected between one input terminal and the output terminal of the operational amplifier A1. The fourth resistor R4 is connected between the other input terminal of the operational amplifier A1 and the ground. The first and second resistors R1 and R2 are adjustable resistors and adjust the mixing ratio between the target compensation current waveform signal V101 and the error signal V102 obtained from the first and second subtracters 101 and 102, respectively. The correction circuit 103 corrects the target compensation current waveform signal V77 after correction shown in FIG. 6 (I) corresponding to the waveform obtained by adding the error signal V102 shown in FIG. 6 (H) to the target compensation current signal V101 shown in FIG. 6 (G). Is output. The corrected target compensation current waveform signal V77 is added to the first-phase load current I1 shown in FIG. 6D to obtain the same sine wave current as the reference sine wave voltage Va shown in FIG. Function as a compensation current command value.

  In the embodiment of FIG. 5, the output of the first subtractor 101 is corrected by the output of the second subtractor 102. However, when the correction by the second subtracter 102 is unnecessary for cost reduction or the like. The second subtracter 102, the correction circuit 103, and the first, second and third current detectors 9a, 9b and 9c can be omitted. When delays in waveform improvement and current balance control do not matter so much, the extraction unit 73 ′, the correction unit 75, the first subtractor 101, and the correction circuit 103 are omitted, and an error obtained from the second subtracter 102 is obtained. The signal V102 can be compensated current feedback control.

  The control signal forming means 78 connected to the target compensation current waveform forming means 77 is a first and second switch for the first and second switches Q1 and Q2 of the first phase of the power conversion circuit 62 shown in FIG. The control signals G1 and G2 are formed by a sawtooth wave generation circuit 104, a comparator 105, and an inverting circuit, that is, a NOT circuit 106. The sawtooth wave generation circuit 104 has a frequency sufficiently higher than the frequency of the AC voltage of the first, second, and third AC input terminals 1a, 1b, and 1c, for example, 50 Hz, for example, 20 to 100 kHz, as shown in FIG. The sawtooth voltage V104 shown in FIG. A comparative wave having periodicity such as a triangular wave can be used in place of the sawtooth voltage V104. One input terminal of the comparator 105 is connected to the correction circuit 103, and the other input terminal is connected to the sawtooth wave generation circuit 104. Therefore, the comparator 105 compares the sawtooth voltage V104 with the target compensation current waveform signal V77 as shown in FIG. 8A, and forms the PWM pulse shown in FIG. 8B as the first control signal G1. This is sent to the gate of the first switch Q1 in FIG. The NOT circuit 106 is connected to the comparator 105 and forms a second control signal G2 composed of an inverted signal of the first control signal G1 in FIG. 8B, and the gate of the second switch Q2 in FIG. Send to.

  The second phase control circuit 72b of FIG. 4 is similar to the first phase control circuit 72a in the third and fourth control signals G3 and G4 for the third and fourth switches Q3 and Q4 of the power conversion circuit 62. Are sent to the gates of the third and fourth switches Q3 and Q4, respectively.

The third phase control circuit 72c forms the fifth and sixth control signals G5 and G6 for the fifth and sixth switches Q5 and Q6 of the power conversion circuit 62 in the same manner as the first phase control circuit 72a. To the gates of the fifth and sixth switches Q5 and Q6, respectively. In the embodiment of FIG. 1, since the load 4 is not connected to the third AC input terminal 1c, the input corresponding to the line 94 to the load current waveform estimation circuit 73 in the first phase control circuit 72a is zero. Yes, the signal corresponding to the corrected estimated waveform signal V75 obtained from the multiplier 75b is also zero. Therefore, what corresponds to the compensation current waveform signal V77 of the first subtractor 101 of FIG. 5 in the third phase control circuit 72c is the reference sine wave corresponding to the corrected reference sine wave voltage Va 'of the output stage of the multiplier 76. It becomes the same as the wave voltage Vc '.
The second and third phase control circuits 72b and 72c also serve as the sawtooth wave generation circuit 104 of the first phase control circuit 72a. However, the second and third phase control circuits 72b and 72c can be independently provided with a circuit corresponding to the sawtooth wave generation circuit 104.

  In the aerial lighting AC power supply apparatus of FIG. 1, when power is supplied to the lamps 42a and 42b included in the load 4, the first and second thyristors S1 and S2 of the power supply controller 3 supply a constant current. In this way, the phase control circuit 5 controls. When the first and second thyristors S1 and S2 are phase-controlled, the load current I1 is turned on during the conduction control periods t1 to t2 and t3 to t4 of the first and second thyristors S1 and S2, as shown in FIG. The flow almost coincides. Therefore, the load current I1 of the first phase and the load current I2 of the second phase include harmonic components. The power conversion circuit 62 adds a compensation current corresponding to the target compensation current waveform signal V77 shown in FIG. 6 (I) to the load current I1 and applies the first phase reference sine wave of FIG. 7 to the first AC input terminal 1a. A sinusoidal AC input current corresponding to the voltage Va is passed, and the second phase load current I2 is compensated, and a sinusoidal wave corresponding to the second phase reference sine wave voltage Vb of FIG. 7 is applied to the second AC input terminal 1b. An AC input current Ib is supplied, and a sine wave AC input current Ic corresponding to the third phase reference sine wave voltage Vc of FIG. 7 is supplied to the third AC input terminal 1c. Thus, the first, second, and third phase AC input currents Ia, Ib, Ic flowing through the first, second, and third AC input terminals 1a, 1b, 1c become sine waves or approximate sine waves, and The first, second and third phase AC input voltages Va, Vb and Vc are in phase or nearly in phase, and the waveform and power factor improvement are achieved.

  The operation of supplying the compensation current by the power conversion circuit 62 in FIG. 2 is well known in the above-mentioned Patent Document 2 and the like, so detailed description will be omitted and only the outline will be described. Since the first to sixth diodes D1 to D6 in FIG. 2 are connected in a three-phase bridge, they function as a three-phase full-wave rectifier circuit. However, when one selected from the first to sixth switches Q1 to Q6 is turned on, a short circuit including the one selected from the first to third inductors L1 to L3 is formed. For example, when the third switch Q3 is turned on while the first diode D1 is forward-biased, the first AC input terminal 1a, the first inductor L1, the first diode D1, the third switch Q3. The current flows through the path of the second inductor L2 and the second AC input terminal 1b, which contributes to the compensation current, that is, the improvement of the waveform and power factor, and the balance of the three-phase current. By controlling the ON time width of the first to sixth switches Q1 to Q6, it becomes possible to flow a compensation current corresponding to the target compensation current waveform signal V77.

  When the first to sixth switches Q1 to Q6 are turned off, the energy stored in the first to third inductors L1 to L3 is released, and the first to third phase AC input terminals 1a to 1c are connected. An output obtained by adding the voltages of the first to third inductors L1 to L3 to the first to third phase AC input voltages Va to Vc is generated, and thereby the smoothing capacitor 63 is charged. Since the voltage of the smoothing capacitor 63 is controlled to a desired value by the DC feedback control signal forming circuit 71 of FIG. 4, it does not become abnormally high but is kept almost constant.

This embodiment has the following effects.
(1) Even if a harmonic component is included in the load current I1 by the phase control of the first and second thyristors S1 and S2 of the power supply controller 3, a compensation current is supplied by the compensation current supply circuit 6; Improvements in current waveform and power factor and noise are achieved.
(2) The single-phase load 4 is connected to the three-phase AC power source, and the first, second and third AC input terminals 1a, 1b and 1c are in spite of being in an unbalanced load state. Since the three-phase compensation current supply circuit 6 is connected, the balance improvement of the three-phase current can be achieved.
(3) Based on the phase control signal Vg1 of the first and second thyristors S1 and S2 of the power supply controller 3 and the reference sine wave voltages Va, Vb and Vc, a load current estimation reference waveform signal V73 'and the like are formed. Target compensation by the difference between the reference sine wave voltages Va, Vb, Vc or the corrected reference sine wave voltages Va ', Vb', Vb 'and the load current estimation reference waveform signal V73' or the corrected waveform signal V75 corrected therefrom. A current waveform signal V101 or V77 is formed and used to control the power conversion circuit 62. That is, the load currents I1, I2, etc. are theoretically estimated and used for controlling the compensation current. Since the theoretically estimated load current waveform has less delay than the actually detected load current, it is possible to reduce the delay in supplying the compensation current and achieve good compensation.
(4) The target compensation current waveform signal V77 is not formed only by the load current estimation reference waveform signal V73 'or the estimated waveform signal V75 obtained by correcting it, and the error signal V102 obtained from the second subtracter 102 shown in FIG. Since the target compensation current waveform signal V77 is formed by applying the correction, the waveform and the power factor can be improved satisfactorily.
(5) Since the load current estimation reference waveform signal V73 ′ is corrected with the amplitude adjustment value a, an accurate load current estimation waveform signal V75 can be obtained.

    Next, an AC power supply apparatus according to the second embodiment will be described with reference to FIG. A modified power conversion control circuit 7a according to the second embodiment shown in FIG. 9 is obtained by modifying a part of the power conversion control circuit 7 of the first embodiment in FIG. The AC power supply device according to the second embodiment is configured in the same manner as in FIGS. 1 to 5 except for the power conversion control circuit 7a. Accordingly, in FIG. 9 and FIG. 10 for explaining this operation, the same parts as those in FIGS. In the description of the second embodiment, FIGS. 1 to 8 are referred to as necessary.

  The modified power conversion control circuit 7a of FIG. 9 omits the extracting means 73 ′ of FIG. 4 and moves the multiplier 75b of the correcting means 75 to the output stage of the correcting means 76 of the reference sine wave voltage Va, and FIG. A compensation component extraction circuit 110 is provided in place of the first subtractor 101, and the other components are substantially the same as those shown in FIGS.

  The multiplier 75b is modulation means for modulating the amplitude of the reference sine wave Va 'so as to correspond to the output of the load current detector 8. One input terminal of the multiplier 75b is connected to the correcting means 76, and the other input terminal is connected to the amplitude adjustment signal forming circuit 75a. Accordingly, the multiplier 75b multiplies the reference sine wave voltage Va 'obtained by correcting the reference sine wave voltage Va with the DC feedback control signal V71 by the amplitude adjustment value a obtained from the amplitude adjustment signal forming circuit 75a to obtain Vx = a. * Va 'is output. The output Vx of the multiplier 75b substantially corresponds to the target current waveform of the first AC input terminal 1a. In the second embodiment shown in FIG. 9, the multiplier 75b is arranged at the output stage of the correcting means 76. Instead, it is arranged between the reference sine wave generating means 70 and the correcting means 76, or the correcting circuit 103. And the control signal forming means 78. In short, the multiplier 75b may be arranged at a place where the amplitude of the target compensation current can be adjusted by some method according to the change of the load current I1, or an amplitude adjusting means having an equivalent function to the multiplier 75b may be provided.

  The target compensation current component extraction circuit 110 is an extraction unit that extracts a portion corresponding to a period in which the phase control signal Vg1 indicates a non-conduction period from the reference sine wave obtained from the reference sine wave generation unit 70. The circuit 111 and the extraction switch 111 are included. The extraction switch 112 is connected between the multiplier 75 b and the correction circuit 103. The NOT circuit 111 is connected between the phase control signal line 94 and the control terminal of the extraction switch 112, and an extraction control signal V111 comprising an inverted signal of the phase control signal Vg1 of FIG. 10C is shown in FIG. Output as follows. The extraction switch 112 extracts the period t0 to t1 and the period t2 to t3 in FIG. 10 of the output Vx of the multiplier 75b in response to the extraction control signal V111 in FIG. The compensation current signal V110 is sent to the correction circuit 103. The target compensation current signal V110 in FIG. 10 (G) is substantially the same as the target compensation current signal V101 in FIG. 6 (G). The correction circuit 103 in FIG. 9 has the same configuration as that indicated by the same reference numerals in FIGS.

  FIG. 10 shows the state of each part of FIGS. 3 and 9 in the same manner as FIG. (A) to (D), (H), and (I) in FIG. 10 are the same as (A) to (D), (H), and (I) in FIG.

  Also in the power conversion control circuit 7a of FIG. 9, since the target compensation current signal V77 is formed using the phase control signal Vg1, it is possible to supply a compensation current with little delay with a relatively simple circuit. In addition, the same effect as that of the first embodiment can be obtained by the second embodiment.

  FIG. 11 shows a main circuit portion of the AC power supply device according to the third embodiment. In the AC power supply apparatus according to the third embodiment, the first load 4a is connected between the first and second AC input terminals 1a and 1b via the first power supply controller 3a, and the second and third AC input devices are connected. A second load 4b is connected between the input terminals 1b and 1c via the second power supply controller 3b, and between the first and third AC input terminals 1a and 1c via the third power supply controller 3c. A third load 4c is connected. A three-phase compensation current supply circuit 6 is provided between the first, second and third AC input terminals 1a, 1b and 1c and the first, second and third power supply controllers 3a, 3b and 3c. A branch circuit is connected to the power supply line. That is, the first, second and third power supply controllers 3a, 3b and 3c and the three-phase compensation current supply circuit 6 are connected in parallel.

  The first, second and third power supply controllers 3a, 3b and 3c are composed of an antiparallel circuit of two thyristors, similar to the power supply controller 3 of FIG. The first, second, and third loads 4a, 4b, and 4c include an aerial lighting lamp as in the load 4 of FIG. 1, and have the same or different impedance. The phase control circuit for the first, second, and third power supply controllers 3a, 3b, and 3c in FIG. 11, the power conversion control circuit for the compensation current supply circuit 6, and the voltage and current detection means associated therewith. Is substantially the same as that shown in FIGS. Therefore, the same effect as that of the first embodiment can be obtained by the third embodiment of FIG.

The present invention is not limited to the above-described embodiments, and for example, the following modifications are possible.
(1) Instead of configuring the power supply controllers 3, 3 a, 3 b, and 3 c with thyristor antiparallel circuits, a triac, an IGBT antiparallel circuit, a transistor or FET antiparallel circuit, or a combination of a phase controllable switch and a diode It can be replaced by a known AC switch such as a circuit.
(2) The configuration is such that power is supplied to the single-phase load 4 from the single-phase AC input terminal corresponding to the configuration in which the third AC input terminal 3c in FIG. 1 is omitted, and the compensation current supply circuit 6 is also single-phase. Can be configured in a circuit.
(3) In FIG. 11, the third power supply controller 3c and the third load 4c can be omitted.
(4) Instead of using the power supply controllers 3, 3a, 3b, and 3c as current controllers, they can be used as voltage controllers or current and voltage controllers or power controllers. In the case of the voltage controller, an output voltage detection circuit for detecting the voltage between the first and second AC output terminals 2a and 2b or the voltage of the load 4 is provided, and the voltage feedback signal is based on the output of the output voltage detection circuit. And the phase control circuit 5 is modified to make the output voltage constant by using this voltage feedback signal. In the case of a current and voltage controller, the voltage control function is added to the current control phase control circuit 5. Further, in the case of a power controller, a load power feedback signal is formed, and the phase control circuit 5 is modified so that the load power is constant by using this load power feedback signal.
(5) The output transformer 40 of the load 4 is a step-down transformer, or is configured to obtain a voltage slightly higher than or equal to the voltage of the primary winding N1, or the same voltage from the secondary winding N2. In addition, a constant output voltage identical to the AC input voltage between the second AC input terminals 1a and 1b can be obtained, or the output transformer 40 can be omitted.
(6) The AC side line 64a of the power conversion circuit 62 is an insulating transformer or an autotransformer for lowering the voltage of the first, second and third AC input terminals 1a, 1b and 1c and supplying the voltage to the power conversion circuit 62 , 64b, 64c.

  The AC power supply apparatus of the present invention can be used for a constant current power supply for aeronautical lighting.

It is a circuit diagram which shows the alternating current power supply apparatus of Example 1 of this invention. It is a circuit diagram which shows in detail the power converter circuit of FIG. FIG. 2 is a block diagram showing in detail the phase control circuit of FIG. 1. It is a block diagram which shows the power conversion control circuit of FIG. 1 in detail. FIG. 5 is a block diagram showing in detail the first phase control circuit of FIG. 4. It is a wave form diagram which shows the state of each part of FIG.3 and FIG.4. It is a wave form diagram which shows the output of the reference | standard sine wave generation means of FIG. It is a wave form diagram which shows the input and output of the comparator of FIG. FIG. 5 is a block diagram illustrating a power conversion control circuit according to a second embodiment as in FIG. 4. It is a wave form diagram which shows the state of each part of FIG.3 and FIG.9. FIG. 6 is a circuit diagram illustrating a main circuit portion of an AC power supply device according to a third embodiment.

Explanation of symbols

1a, 1b, 1c 1st, 2nd and 3rd AC input terminals 2a, 2b 1st and 2nd AC output terminal 3 Feed controller 4 Load 5 Phase control circuit 6 Compensation current supply circuit 7 Power conversion control circuit 42a 42b Aviation lighting lamp 62 Power conversion circuit 63 Smoothing capacitor

Claims (13)

AC input terminal,
An AC output terminal to which a load is connected;
A power feeding controller including a phase-controllable semiconductor control element connected between the AC input terminal and the AC output terminal and controlling a current or voltage of the AC output terminal or both;
A phase control circuit that forms a phase control signal of the semiconductor control element and sends it to the semiconductor control element;
A pulse width modulation type for supplying a compensation current for improving distortion of a current waveform caused by phase control of the semiconductor control element, connected to the AC input terminal and supplying a compensation current A compensation current supply circuit including a power conversion circuit of
An AC power supply apparatus comprising: power conversion control means for performing on / off control of a switch included in the power conversion circuit. The power conversion control means includes
Load state detecting means for detecting the current or voltage at the AC output terminal or both, and
A reference sine wave generating means for generating a reference sine wave synchronized with the AC voltage at the AC input end;
Connected to the phase control circuit, the load state detection means, and the reference sine wave generation means, and forms a target compensation current waveform based on the phase control signal, the output of the load state detection means, and the reference sine wave. Target compensation current waveform forming means;
A switch that is connected to the target compensation current waveform forming means, forms a switch on / off control signal for supplying a compensation current corresponding to the target compensation current waveform, and controls the switch by the switch on / off control signal 2. The AC power supply apparatus according to claim 1, comprising control signal forming means. The target compensation current waveform forming means includes:
An estimated current waveform is output by theoretically estimating the waveform of the current flowing through the AC output terminal based on the phase control signal and the output of the load condition detecting means, connected to the phase control circuit and the load condition detecting means. Current waveform estimating means for
And subtracting means for forming a target compensation current waveform corresponding to a difference between the reference sine wave obtained from the reference sine wave generating means and the estimated current waveform obtained from the current waveform estimating means. The AC power supply device according to claim 2 The current waveform estimation means includes
An extraction means connected to a phase control circuit and the reference sine wave generating means, and extracting a portion corresponding to a conduction period of the phase control signal of the reference sine wave;
A load amount detecting or calculating means connected to the load state detecting means for detecting or calculating a load amount indicating an effective value or an average value of the current or voltage or power of the AC output terminal;
And a correction means for correcting the amplitude of the waveform extracted by the extraction means with a signal indicating the load quantity obtained from the load quantity detection or calculation means and outputting an estimated current waveform. Item 4. The AC power supply device according to Item 3. The target compensation current waveform forming means includes:
Extraction means for extracting a portion corresponding to a period in which the phase control signal indicates a non-conduction period from the reference sine wave obtained from the reference sine wave generation means;
Correction means for correcting the amplitude of the reference sine wave before or after extraction of the reference sine wave by the extraction means based on the output of the load state detection means so as to correspond to the output of the load state detection means The AC power supply device according to claim 2, comprising:   The phase control circuit includes a reference value generating unit that generates a signal indicating a reference value of the current, voltage, or power of the AC output terminal, and a signal indicating the load state detected by the load state detecting unit as the reference value. 6. The AC power supply apparatus according to claim 1, further comprising phase control signal forming means for forming a phase control signal of the semiconductor control element so as to coincide with each other. The compensation current supply circuit includes:
An AC terminal connected to the AC input for supplying a compensation current;
A pair of DC terminals;
Pulse width modulation type comprising a plurality of semiconductor switches bridge-connected between the AC terminal and the pair of DC terminals, and a plurality of individual or parasitic diodes connected in parallel in the reverse direction to the plurality of semiconductor switches, respectively. Power conversion circuit of
A smoothing capacitor connected between the pair of DC terminals;
An inductor connected in series in a current path between the AC terminal and the power conversion circuit;
The AC power supply according to any one of claims 1 to 6, further comprising a filter capacitor connected between a plurality of current paths between the AC terminal and the power conversion circuit. apparatus. A DC voltage detection circuit for detecting a voltage between the pair of DC terminals;
A reference voltage source for generating a reference voltage indicating a target voltage between the pair of DC terminals;
A DC feedback control signal forming circuit for forming a DC feedback control signal indicating a difference between the output of the DC voltage detection circuit and the reference voltage;
8. The AC power supply apparatus according to claim 2, further comprising a correcting unit that corrects an amplitude of the reference sine wave or the target compensation current waveform by the DC feedback control signal. 9. The target compensation current waveform forming means includes:
First subtracting means for subtracting the estimated current waveform estimated by the current waveform estimating means from the reference sine wave or the reference sine wave corrected with the DC feedback control signal;
Input current detection means for detecting an input current flowing through the AC input end;
Second subtracting means for forming an error signal with the output of the input current detecting means from the reference sine wave or the reference sine wave corrected with the DC feedback control signal;
9. The AC power supply apparatus according to claim 3, further comprising means for correcting an output of the first subtracting means with an error signal obtained from the second subtracting means. The target compensation current waveform forming unit is further configured to detect a load amount connected to the load state detection unit to detect or calculate a load amount indicating an effective value or an average value of the current, voltage, or power of the AC output terminal. Or having computing means,
The correction means is means for modulating the amplitude of the reference sine wave or the reference sine wave corrected by the DC feedback control signal based on the output of the load amount detection or calculation means,
The extraction means is means for extracting a portion corresponding to a period in which the phase control signal indicates non-conduction from the reference sine wave, the corrected reference sine wave, or the modulated reference sine wave.
The target compensation current waveform forming means further includes an input current detection means for detecting an input current flowing through the AC input terminal, the reference sine wave, the corrected reference sine wave, or the modulated reference sine wave. And subtracting means for forming an error signal between the input current detecting means and means for correcting the output of the extracting means with an error signal obtained from the subtracting means. Item 6. The AC power supply device according to Item 5. The load connected to the AC output terminal is a circuit including an aerial lighting lamp,
The semiconductor control element is a thyristor;
11. The AC power supply device according to claim 1, wherein the phase control circuit is a circuit that controls a phase control angle of the thyristor so as to supply a constant current to the load. The AC input terminals are first, second and third AC input terminals for supplying a three-phase AC voltage,
The AC output terminal is for connecting at least one single-phase load;
2. The AC power supply apparatus according to claim 1, wherein the power conversion circuit is a three-phase power conversion circuit. First, second and third AC input terminals for supplying a sinusoidal three-phase AC voltage;
A power supply controller including a phase-controllable semiconductor control element connected between the first and second AC input terminals via a single-phase load circuit and controlling a load current and / or a voltage;
A phase control circuit that forms a phase control signal of the semiconductor control element and sends it to the semiconductor control element;
A compensation current is connected to the first, second and third AC input terminals and for improving the waveform and current balance of the current flowing through the first, second and third AC input terminals. An AC power supply device comprising: a compensation current supply circuit having a three-phase configuration having a function of supplying.

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