JPS589579A - Circuit for controlling reversible power conversion - Google Patents

Abstract

PURPOSE:To obtain highly reliable control operation by connecting gates which are opened and closed in response to the respective output signals of multiplexed detecting circuit in series, and performing switching based on the conditions that all gates are opened or closed. CONSTITUTION:A reversible power converter TH is provided between an AC bus line AL and the reversible input and output of the power, and selectively operates either of a thyristor circuit THF or THR based on the transmitting direction of the power. The transmitting direction of the multiplexed power is detected by power transmitting direction detecting circuits DCD1 and DCD2. The zero current state of the DC bus line of the thyristor circuits detected by zero current detecting circuit ZCD1 and ZCD2. A flip flop circuit is operated by both detector circuits, and a plurality of the gates B1-B4 are opened and closed by the outputs. Only when it is detected that the gates B1 and B2 and B3 and B4, which are connected in series, are all opened or closed by a detector DET, the outputs which supply the gate signals are generated.

Description

[Detailed Description of the Invention] The invention includes an AC bus and reversible input/output of power to the AC bus! As soon as it is inserted between the Ri position 1
The present invention also relates to a reversible power conversion control circuit that selectively operates the second thyristor circuit in accordance with one of the power transfer directions.

Conventionally, this type of □ circuit was shown in FIG. 1. In FIG. 1, the reversible power converter TH includes a three-phase AC bus ALK transformer TR' and a first thyristor circuit THF that is connected via an intermediary and transfers power from the AC bus AL to the DC machine M; has a second thyristor circuit THR that transfers power in the reverse direction, and is used so that the gate signals GF and GR are supplied from the gate distribution circuit CD. A voltage sensor tvS that detects the voltage between 7 is connected between the DC buses P and N of the reversible converter @TH, and a reactor L and a current sensor fsH are connected in parallel with this voltage sensor S. 1st class machine M is connected via 'i 1t1z
There is. The current sensor SH is the kth one that detects the current flowing through it. The zero current detection circuit ZCD detects the DC bus # by the output signals of the gate pulse generation circuit GPG, the voltage sensor vS, and the current sensor SI.
P.

Detects the presence of NK current. DCD is a circuit that detects the direction of power transfer.

FIG. 2 shows a detailed diagram of the gate signal distribution circuit GD.

This circuit detects current and force transfer detection circuit DCD on the condition that the output of zero current detection circuit ZCD is at rlJ level.
In response to the output of , the 91st woman connects a D-flip-flop that outputs Q, and in response to this output, gate No. 48 GP is connected to GF'.
! The hole is constituted by AND circuits C and D which output as GR. Figure 3 shows the operating waveforms of each part of the circuits in Figures 1 and 2. Figure 3 (a) is the output waveform of the voltage sensor vS, and (b) is the output waveform of the gate pulse ordering circuit GP.
(e) is the output waveform of current sensor SH, (
d) is the output waveform of the power transfer direction detection circuit DCD, (,)
is the output waveform of the zero current detection circuit ZCD, (f) is the Q output waveform of the D-7 lip-flop, and (2)) is the gate signal GF.
and (Xun shows the waveform 17 of Gutoi September GR. As can be seen from this waveform, the gate signal GPt
j, depending on the output of the power transfer direction detection circuit DCD, on the condition that the output of the zero current detection circuit ZCD is rlJ,
The thyristor circuit THF is supplied with THRl/(.This operation results in switching between the thyristor circuits THF and THR without circulating current.

However, in the conventional circuit as described above, the zero current detection circuit MZ
If the CD output changes significantly due to a failure or the like, or if AND circuits C and D in Figure 2 fail and work so that both Q and Q outputs are judged as "1", the main circuit current (Nevertheless, there are major drawbacks such as the gate signal switching not being executed and the gate signal being supplied to both the iris register circuit THF and THR.)

This invention eliminates the drawbacks of the conventional circuit as described above, and is designed to provide a multiplexed t'I six-detection six-output circuit when switching between thyristor circuits of a reversible power converter. Highly reliable control operation can be obtained by connecting gates that open and close in series with each output signal, and switching between each gate depending on whether it is closed or open. The object of the present invention is to provide a high-power reversible conversion control circuit M in this manner.

An embodiment of the present invention will be described below with reference to FIG.

In this example, the case where the signal is doubled and large is shown, or the case where the signal is tripled or multiplexed to a large extent is also shown. Figure 4 Kl
In addition, ZCD1 and ZCD2 are mutually independent six-zero electric perspiration detection circuits having the same functions as the one shown in FIG. 2 KZCD, and DCDI and DCD2 are power transfer direction detection ports having the same functions as the DCD in FIG. 121 respectively. Madai B1. B2゜B3. B4 is the signal line BIG, B2G, B
3G.

The gates R1-R6 are fixed-leg resistors that are opened (conductive) when the rlJ signal is supplied through B2O. Resistors R1 to R4ti are connected in parallel to gates B1 to B4, one large resistor R5Fi is connected to resistor R1゜R2, and resistor R6 is connected to resistors R3 and R4 in series t'L, respectively, to form a resistor circuit 12I. and each resistor circuit has a bias circuit BIAS.
The voltage of the foot is applied. The big nE'rt
This is a potential detection circuit that detects the potential between i-numbered lines GF and GR.

The zero potential detection circuits ZCD1, ZCD2, power transfer detection circuits NDCD1, DCD2, and two sets of D-flip-flops operate normally, and the signal -1' on the signal line BaO is
! If Q is "l", the signal on the old lines BIG and B4C will be "0", the signal on the Shingetsu line BJG will be rlJ,
Gates B3 and B4 open as the holes open. For this reason 2
Assuming that no voltage is applied between the ends of the resistor R6 from the 477 circuit BIAS, and the potential is zero, which is the potential on the line GP,
The potential on the signal line GF is zero potential. On the other hand, Goo) B1
, B2 is closed and 69, and the output voltage of the bias circuit 12iBIAs is -EB, a potential expressed as follows appears on the signal line GR. That is, when the control circuit is operating normally, the potential of one of the signal lines GF and GR is zero (zero), and the potential of the other one is the sum of the two.

On the other hand, some kind of failure occurs in the circuit described above, and only one of the two gates connected in series opens (1
(For example, game)
If we consider the case where B3 is open and gate B4 is closed, we have two holes:
When comparing the potential of the signal line GF with the potential in a normal case, the relationship is as follows. In other words, when the above-mentioned failure occurs, the potential of the signal line CF becomes higher than when it is normal.

The detection circuit DET detects the potentials of the signals iGF$> and GR, and generates an output signal when the value of β is within the range determined by . If the value of β is within the above range, it means that the gates connected to each other in Km columns are not in the open state (closed), so by detecting the value of β, , Good Toy September distribution circuit G D K 48 months provided! It is possible to detect malfunctions in a range that includes circuits. The output signal of the detection circuit DET is sent to the signal line GSK and is used to immediately stop the gate pulse generation circuit GPG.

As described above, in the present invention, an independent πD flip-flop circuit is provided, which is independently driven by the outputs of the zero current detection circuit and the current transfer direction detection circuit, and is connected in series with each other. 1172: A plurality of darts are inverted and supplied in accordance with the relationship between the Q output of each D-flip-flop circuit and the Q output 'ft. The relationship between the main gate and the output of each D-flip-flop is that during normal operation, they are connected in series and all the large gates are open and the first hole is closed, but when an abnormality occurs, some of the large gates are open and the first hole is closed. , the rest are set up so that the opposite situation occurs. The open/close state of this gate is detected by a detection circuit, and a gate pulse is supplied to the selected thyristor circuit on the tπ side only when the gate is in a normal state. Even if only a part of the multiplexed Fiff circuit malfunctions, the supply of the gate signal to the thyristor circuit is immediately stopped, resulting in highly reliable control.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional power reversible conversion control circuit, FIG. 2 is a block diagram of its gate signal distribution circuit, FIG. 3 is a diagram of operation waveforms, and FIG. 4 is a power supply according to an embodiment of the present invention. FIG. 3 is a block diagram of a gate signal distribution circuit of the reversible conversion control circuit. TH...Power converter circuit, THF, THR...
Cyrisk circuit, AL...AC bus, TR...transformer, M...DC machine, ■S...voltage sensor, SH-...
・Current sensor, GD...Gate signal distribution circuit, P, N
...DC bus, ZCD...zero current detection circuit, GPG
...Gate pulse generation circuit, DCD...Power transfer method detection circuit. 〇Representative: Haku Kuzuno (and 1 other person) Written amendment to procedures for Figures 1≦3 (voluntary) December 16, 1982 2, Name of the invention: Reversible power conversion control circuit 3. Relationship with the person making the amendment: Patent applicant representative Kata Yuhito Department 4: Agent ('+) 5. Detailed description of the invention in the specification to be amended Column 6, Contents of correction (1) In the second line of page 6 of the specification, the phrase "zero potential detection circuit" is corrected to "zero current detection circuit." (2) On page 6, line 10 of the specification, the statement "assuming the potential on GP is zero potential" is corrected to "assuming the potential on GP is positive potential". (3) In the 11th line of page 6 of the specification, the statement "The potential is zero potential" is corrected to "The potential is positive potential." (4) On page 6, line 14 of the specification. (5) On the last line of page 6 of the specification. (6) On page 7, line 5 of the specification, “Game) B3 is open, Game)
The phrase "B4 is closed" is corrected to "[game] B4 is open and gate B3 is closed." (7) In the specification, page 7, line 7, (8) Ming11iBtIIk, page 7, line 9 is corrected. (9) The statement on page 7, line 14 of the specification is amended as follows.

Claims (1)

[Claims] 1 is inserted between the AC bus and a device that performs reversible input/output of power to the AC bus, and one of the first and second thyristor circuits is selected depending on the direction of power transfer. a power transfer direction detection circuit that is multiplexed and detects the direction of transfer of high power, and a zero current detection circuit that detects the zero current state of the DC bus of the thyristor circuit; A flip 7μ tube circuit driven by the output of the power transfer direction detection circuit and zero current detection circuit, and a plurality of gates that are opened and closed by the output of the 7 flip-flop circuit are connected in series with each other so that all six gates are open or closed. and a detection circuit that generates an output for supplying a gate signal -@ to one of the thyristor circuits only while detecting that the thyristor circuit is in the thyristor circuit.