JPS60106358A - Power converter - Google Patents

Abstract

PURPOSE:To reduce the number of wirings for transmitting a control signal and to improve the noise resistance property of a power converter by feeding the control signal as serial data to a main circuit, synchronizing the data in the main circuit to control a main circuit section. CONSTITUTION:A control signal generated by a control circuit 1 in a control circuit section 10 is converted by phase shifters 3A-3C and a serial transmitter 100 to serial data, converted by an electro-optical converter 102 into an optical signal, and transmitted through an optical fiber 103. The transmitted signal is converted by an optical-electric converter 201 into an electric signal, and received by transceivers 203, 303, 403 of a sequential main circuit section 20. The parallel data received by receivers 203, 303, 403 at every main circuit sections are synchronously latched by circuits 209, 309, 409. Main circuit bridges 5A-5C are controlled on the basis of the data.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a power conversion device, and in particular, a control circuit section and main circuit sections of a number of units controlled by the control circuit section are separated from each other, and the present invention relates to a power conversion device. This relates to a power conversion device in which control information to the main circuit section is transmitted as serial data to control a plurality of main circuit sections.〇 [Technical background of the invention and its problems] In recent years, steel rolling processes, etc. DC Leonard and cycloconverters are used to convert AC input power into DC or AC power is obtained.

These power conversion devices include a control circuit section that handles weak control signals and a main circuit section that handles high power such as a thyristor, so as an integrated structure, they can be used in environments where temperature, humidity, etc. are controlled to constant values. Although it is desirable to install it in a good electrical room, since the installation area becomes large, there is a problem in terms of effective use of the electrical room space, and it is also a factor that increases the construction cost of the electrical room.

In order to make effective use of electrical room space and reduce construction costs of electrical rooms, conventional power converters were divided into two components: a control circuit section that took up a small space but was sensitive to changes in the external environment such as temperature and humidity; The main circuit section is divided into parts that are relatively strong against environmental changes, and only the control circuit section is housed in the electrical room where it is protected from the environment.The main circuit section, which occupies a large space, is installed outside the electrical room, and a large number of controls are installed in between. fljl connected with a line
A '-4 force converter with a section/main circuit section structure type is used in the J-times.

FIG. 1 shows an example of a conventionally used power conversion device of the split structure type described above. FIG. 1 shows a well-known flow Leonard device which is often used in a variable rolling king drive, and the main circuit section has a three-stage cascade structure in order to cope with large fluctuations.

In FIG. 1, 10 is a control circuit section, which is installed in an electrical room with a good environment. This includes control circuit 1
Therein, calculations for speed control of the DC motor 31, which will be described later, are performed, and a voltage command signal S2A is generated.

s2B and s2c are output to lines 2A, 2B, and 2C.

3A, 3B, and 3C phase shifters operate in response to voltage commands and generate firing pulse signals for the main circuit bridge 5A.For example, from 3A, the thyristor firing pulse (k number 4A is generated and the signal line 4A
It is sent to the five main circuit bridges through.

Similarly, the ignition pulse signal emitted from 3B is the signal line 4B.
The ignition pulse signal emitted from 3C is sent to the main circuit bridge 5C through the signal line 4C.

These signal lines 4A, 4B, and 4C are signal lines that transmit electrical signals. Numeral 8 is a pit for storing signal lines dug in an electrical room, etc., and signal lines 4A, 4B, and 4C are laid in this pit 8 and led to the main circuit 20.

Reference numeral 20 denotes the main circuit section, which has a large outer diameter of 1M and is therefore installed in a location away from the electrical room where there is a relatively large amount of space. At this time, the signal line laying pit 8 that connects the control circuit section 10 and the main circuit section 20 is usually long, several hundred meters long. 05A, 5B, and 5C are main circuit bridges; It is housed in the circuit section 20. 3
0 is a rolling machine machine section, which consists of a DC motor 31 and a load 32, and the DC motor is operated by electric power supplied through power supply lines 21+22.

The conventional power converter configured in this way is advantageous in terms of vertical utilization of electric room space and reduction of electric room construction costs, but the signal lines 4A, 4B, and 4C are long, so the signal lines are There is a problem in that noise is added to the control and reduces the reliability of the control. Furthermore, since a large number of signal lines are laid in the pit 8, the external size of the pit becomes large, which increases the cost of constructing the pit and lowers the cost of wiring work.

[Object of the Invention] The present invention provides a power conversion device in which a control circuit section and a plurality of main circuit sections are arranged separately, in which a main circuit section is connected to a main circuit section.
! The purpose of this invention is to provide a highly reliable power conversion device that transmits control signals to two circuit sections as serial data, thereby reducing the number of wiring lines for transmitting control signals and improving noise resistance. .

[Summary of the Invention] The present invention provides a power conversion device in which a control circuit section and a plurality of main circuit sections are arranged separately, and the control circuit section controls the plurality of main circuit sections via a signal transmission path. A serial transmission circuit that converts the signal generated in the main circuit section into serial data and transmits it, a serial transmission line that transmits the serial data, and a serial transmission circuit that receives the transmitted serial data and converts it into parallel data for each main circuit section. It is equipped with a receiving circuit and a latch circuit that synchronizes the parallel data of each main circuit section in accordance with the common control cycle of each main circuit section, thereby controlling the arrangement of the signal transmission path. By reducing the number of transmission pits, construction costs and wiring man-hours for transmission pits are reduced, and electrical noise is also reduced and reliability is improved.

[Embodiments of the invention] An embodiment of the present invention is shown in FIG.

In FIG. 2, for the control circuit section, the control circuit 1
Voltage command SIl'A+ "2B+ "' issued from
The phase shifters 3A, 3B, and 3C operate based on the voltage, and output the ignition pulse control signal No. 8 S4A, +S4B+S4C to the lines 4h, 4B, and 4C.

The control signal S 4 A+ 84 B+ S 4 C is parallelized data consisting of a plurality of logic value signal signals, and is sampled at a constant cycle by the serial transmitting circuit 100, and is sequentially transmitted as a serial data signal S 101 to the signal line 101. is output to.

Reference numeral 102 denotes an electrical/optical converter which converts the serial data signal Sloi, which is an electrical signal, into an optical signal and sends it to the optical fiber transmission line 103. 8 is the power distribution bit where the power cable is laid, and the optical power converter 103 is also laid in bit 8. The power conversion section 200, 300 is divided into three parts.
Installed independently as ゜400.

In the power conversion unit 200, reference numeral 201 is an optical/electrical conversion unit, which converts the optical signal that has entered through the optical fiber 103 into an electrical signal, and outputs it as a serial data signal 5202 to the line 2.
Output to 02.

The serial data signal 5202 is input to the transmitting/receiving circuit 203, and in this circuit, for example, a control signal 84A issued to the signal line 4A in the control circuit section IO is input to the power converter section 203.
If it is assigned to 00, the control signal 84A (signal on line 4A) sent as serial data is sequentially taken in and parallelized data 89f14 is sent to line 204.
Serial data other than that assigned to itself is output to the I signal line 205.

Reference numeral 206 denotes an electrical/optical converter that converts the electrical signal input through the signal line 205 into an optical signal and sends it to the next stage power conversion section 300 via the optical fiber 211.

2071d is a reception completion detection circuit that checks the data on the output signal line 205 of the transmission/reception circuit 203, checks that the transmission/reception circuit 203 has received all the data that the power conversion unit 200 should receive, and sends the reception completion signal 820B to the line 208. Output to.

A first latch circuit 209 captures and holds data on the output line 204 of the transmitter/receiver circuit 203 based on the command of the reception end signal 8208, and the output line 210 receives the control signal in the control circuit section 10 described above. 4 S4A is reproduced.

222 is a delay circuit which is activated at the same time as the reception end signal 8208 is generated, and generates a delayed latch signal S8 on line 223 after a certain period of time.

220 is a second latch circuit, and a delayed latch signal 822
Based on the command No. 8, the output data S1nto of the first latch circuit described above is fetched and held. In this case as well, the output signal 8221 (signal on line 221) reproduces the above-mentioned signal 84.

5 is a main circuit bridge, which controls the firing of the Zyristor using the signal S221 as a command, outputs a DC voltage to the line 21, and supplies it to the DC machine 3.

The same applies to the power conversion units 300 and 400. In other words, the minor sign 201.20.3 in the power conversion unit 200
゜207, 209.220.222.5A and its ship symbol 202.204.205゜208, 210.221.
223 is an element symbol 30.1.223 in the power conversion unit 300.
303.307.309.320.322.5B and its line symbols 302, 304.305.308.310. −
321.323, and the element symbol 401.323 in the power conversion unit 400. , 403.407.409°420
, 422.5C and its line signals 402.4o4, 4o5
．． 408.410° correspond to 421 and 423, respectively.

In addition, the element 206 of the power conversion unit 200 and the optical fiber 21
Number 1 corresponds to 306 and 311 in the power conversion unit 300, respectively.

However, in the power conversion section 200, the control signal S4A for the control circuit section is reproduced at the signal 8 in the whistle and force conversion section 200, and the main circuit bridge 5A is controlled based on it. On the other hand, in the power conversion section 300, the control circuit section 10
The control signal 84B in s4 is assigned, and the control signal s4
B is reproduced at the signal 8821 in the power converter 300, and the main circuit bridge 5B is controlled based on this.

Similarly, in the power conversion unit 400, the control signal s4c in the control circuit unit IO is assigned, and the control signal 84C is reproduced at the signal 8421 in the power conversion unit 400, and based on this, the main circuit bridge 5C is controlled.

Next, the operation shown in FIG. 2 will be explained with reference to the timing diagram shown in FIG. 3.

FIG. 3 shows at what timing the control signals 54AI S4B, S4C generated in the control circuit section 10 in FIG.
, shows whether it is transmitted up to 5C. In other words, the symbol S4A+ ``'4BI S4C in Figure 3 is the second
Phase shifters 3A, 3B, and 3C in the control circuit section 10 shown in the figure
8101 indicates the ignition pulse control signal generated by
shows the order in which the above-mentioned side f wholesale signals S4A, S4B+84C taken into the serial transmitting circuit 100 of FIG. 2 are sent out as serial data.

Further, the symbol 8210.5810+8410 in FIG. 3 indicates at what timing the above control information S4A, 84B, S4C is taken into the first latch circuit 209.309.409, and the parallel symbol 5221+5i321+54
21 indicates at what timing the output of the first latch circuit 209.309.409 is taken into the second latch circuit 220.320.420.

When the serial transmission circuit 100 samples and takes in the control signals S4A, 84B, and s4c at time tll, the data "4Al + "4B1 + 84CI
is sent to the optical fiber 103 as serial data in the l1lff order indicated by symbol 8101.

That is, the control data 54AI between time points ill and tlB
However, between time points t12 and 118, the control data 84Bl is
The control data 54C1 is 111 between time points tlB and tel.
Next sent. Therefore, at time tll-t21, the serial transmitting circuit 100 outputs the control signals 54A1, 84Bl,
This is the sampling period Ts for sampling 84C1.

At time t12, the serial transmitting circuit 100 has finished transmitting the control data 84, and at this point, the transmitting/receiving circuit 203 in the power converter 200 contains the control data 5.
4AI is being sent, and the data is on the output line 204.
appears in At the same time, the reception end detection circuit 207 operates to generate a reception end signal 8208, and the first latch circuit 209 takes in the signal 5204 according to the command of 8208 and outputs it as a signal S210. That is, the signal 521ol:
Control data S 4Al are reproduced at time tHB Fi.

Next, at time tlB, the serial transmission circuit 100 has finished sending out the control data 84Bl, and at this point, the control data 84B, 1 has been sent to the transmission/reception active circuit 303 in the power converter 300. , the data is sent to output line 304. At the same time, the reception end detection circuit 307
operates, a reception end signal 5sos is generated, and the first latch circuit 309 takes in the signal 8804 according to the command 18808 and outputs it as a signal 8810. That is, signal 88
10, at time t113, control j+1. 'll data 84Bl is reproduced.

Next, at time tel, the serial transmitting circuit 100 has finished sending out the control data 54C1, and at this point, the control data 84C1 has been sent to the transmitting/receiving circuit 403 in the power converter 400, and the data is is line 404
appears in [At the time of use, the reception end detection circuit 407 operates and a reception end signal S'408 is generated, and the first latch circuit 409 takes in the signal 8404 according to the command of 8408.
Each issue is output as 8410. That is, at time t21, signal 8410? l+ll 011 data 84c
1 is reproduced.

As can be seen from FIG. 3, in the control circuit section, at time t1. l
The control signals S4A, 84B, and 84c are sampled as data at the same time, and the control signals S4A, 84B, and 84c are sampled as data at the same time.
.

It is transmitted to the main circuit section as 54111.84C1.

The control signal 84Al+ 84Bl+ 84C1 reproduced as the output of the first latch circuit in the main circuit section is 82 in FIG.
10.

8810+ Time of 8410 t1211181 t21
are reproduced with a time lag.

On the other hand, as shown in Figure 2, in a multi-stage gM power converter, it is unstable unless firing pulses are simultaneously introduced into the thyristors of the main circuit bridges 5A, 5B, and 5C, for example, due to intermittent output current. This may cause problems, and in some cases, the device may not be able to start up.

The ignition pulse control signals generated in the control circuit 10 must therefore be applied to the main circuit bridge simultaneously.

In the present invention, the following method is used to ensure the simultaneity of the control signals described above.

In other words, the delay circuit 2 in the power conversion section 200 in FIG.
22 delay time tt+j is %Ts of sampling period Ts
When set to , the signal S 210 is taken into the second latch circuit 220 with a time delay of Ts and output as the signal S Lll. Therefore, the time t1g of the signal 8910 in FIG.
The data bλ1 at is reproduced as Z data 54Al in the signal 8221 at a time point tel delayed by TS.

In addition, the delay circuit 32 in the power conversion section 300 in FIG.
When the delay time of 2 is set to X Ts of the sampling period Ts, the signal 8810 is delayed by the time XTs, is taken into the second latch circuit 320, and is output as the signal 5821.

Therefore, the data 84Bl of the signal 5310 in FIG.
Similarly, in the power converter 400 of FIG. 2, if the delay time of the delay circuit 422 is set to zero (N 5410 is reproduced as data 84Bl in the signal 81321) captured, signal 84C
Output as 1.

Therefore, the data 54C1 at the time tel of the signal 8410 in FIG.
It is played back as C1.

Note that in the power conversion section 400, for convenience of explanation, the second latch circuit 420. Although the delay circuit 422 is installed, this is not necessarily necessary, and the first latch circuit output 841
0 may directly control the main circuit bridge 5C.

If the circuit of FIG. 2 is used as described above, the signal 52 of FIG.
The control data 54A1154BII 54C1 at time tel of 21+5821+5421 maintains simultaneity.

That is, the signal 54A generated simultaneously in the control circuit section 10
I S4B and S4C simultaneously receive data 84 at time tll.
^1 + 84BllS4C1, and at the time tel delayed by the sampling period Ts, the control data S4A], 84Bl, 84C1 are simultaneously reproduced in the signal 8221 + "'821 +8421, and thereby the main circuit bridges 5A, 5B.

Since 5C are controlled at the same time, the unstable phenomenon that occurs when current is interrupted, which is a problem in multi-stage cascaded power converters, does not occur, nor does startup/stop failure occur.

[Effects of the Invention] As explained above, according to the present invention, a control circuit section and a plurality of main circuit sections are arranged separately, and the control circuit section and the main circuit section are connected by a transmission path such as an optical fiber. Since the control signal is sent to the main circuit as a serial data and synchronized with serial data within the main circuit to control the main circuit, the following effects can be obtained: (1) The control circuit and main circuit can be Since it can be divided and placed, only the small control circuit section can be placed in the electrical room with a good environment, and the large circuit section can be installed outside the electrical room where there is plenty of space, making the electrical trap space more efficient. This will increase utilization and reduce building construction costs.

(2) The control circuit section and the main circuit section are connected with an optical fiber, and since the original fiber can be used to transmit a single signal, it is possible to prevent electrical noise by 'B(<, '1m +
It becomes a device with high lj4 characteristics.

(8) In principle, the control circuit section and main circuit section are
Since the ftjlJM information can be transmitted with just a single fiber, there is no need for a special bit for storing the original fiber, and pit construction costs and wiring man-hours can be reduced.

(4) In order to cope with the increase in the capacity of power conversion devices, the main circuit section is often connected in multiple stages, but by using the present invention, the power conversion unit manufactured as a single unit can be changed according to the power situation. Operation is possible by simply adding additional devices as needed and connecting them with optical fibers, which reduces installation costs.

As is clear from the effects listed above, according to the present invention, a low-cost and highly reliable power conversion device can be realized.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an example of a conventional control circuit/royal circuit separated type power converter, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIG. It is a timing diagram showing the occurrence state whale. 1... Control circuit 3A, 3B, 3C... Phase shifter 5A, 5B, 5C... Main circuit bridge 8...
Pit 10... Control circuit section 20... Main circuit section 31
...10 current motor 32...Load 100...serial transmission circuit

Claims (2)

[Claims] (1) In a power conversion device in which a control circuit and multiple main 1!21 circuit sections are arranged separately and the control circuit section controls the multiple main circuit sections via signal transmission paths, the power generated in the control circuit section A serial transmitter circuit that converts a signal into serial data and transmits it; a serial signal transmission line that transmits the serial data; and a receiver that receives the transmitted serial data and converts it into parallel data for each main circuit section. circuit and
A power conversion device characterized by comprising a latch circuit that synchronizes the parallel data of each of the main circuit sections in accordance with a control period of co-tracing the W1 section. (2) The power conversion device according to claim 1, wherein an optical fiber is used as the serial signal transmission path, and an electric-to-optical converter and an optical-to-electrical converter are provided before and after the optical fiber.