JP2005333246A - Optical transmission apparatus and power converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly transmit and receive data at each device when a plurality of devices having communication functions are connected via optic fibers and data are successively reproduced and relayed to synchronize control timing based on the received data at each device, and thus to properly control to drive a drive load device in the plurality of devices. <P>SOLUTION: A plurality of power converters 22-1 to 22-4 are connected with an optical transmission path comprising both ways of optic fibers 23 to and from the farthest downstream, and the respective devices 22-1 to 22-4 control the drive load device 14. In this case, if the data comprising optic signals from a controller 21 sequentially received by each converter 22-1 are control data, control based on the control data is applied to the drive load device 14 when a synchronization timing time signal obtained by the power converter from the reception time of the data in the converters 22-1 to 22-4 elapses. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a bidirectional communication between a plurality of power conversion devices that output a voltage or current having a predetermined waveform to a drive load device such as a large-capacity power supply device or a motor drive device, and a control device that controls these power conversion devices. The present invention relates to an optical transmission device and a power conversion device used in an optical transmission system such as a power conversion system that is connected by an optical fiber and sequentially transmits an optical signal from a control device to each power conversion device via the optical fiber.

Conventionally, large-capacity power supply devices and motor drive devices have a power converter having a high-voltage, high-current switching circuit that generates a large current or high voltage waveform, and the current waveform or voltage waveform of the power converter becomes a desired waveform. It is configured to be controlled by both the control device that controls the switching circuit.
Normally, in such a configuration, a plurality of power converters are synchronized in order to adopt a multi-phase configuration for driving a multi-phase motor, a series configuration for high voltage, a parallel configuration for increasing current, and the like. To be controlled. For this reason, a switching command is integrally given as a signal from a single control device to a plurality of power conversion devices. The signal transmission needs to synchronize the timings of a plurality of switchings in a noisy environment due to high voltage switching. For this reason, there are demands for a small transmission delay and reliability with no transmission error.

In addition, the control device and a plurality of power conversion devices are connected by the same transmission cable, and commands from the control device are transmitted to the power conversion devices all at once as electrical signals. For this reason, the power converter connected to the transmission cable can simultaneously receive a command from the control device.
However, since the transmission is based on an electric signal, it is vulnerable to noise, and there is a drawback that the transmission speed cannot be increased because it is necessary to insulate using a pulse transformer or a photocoupler.

  In order to improve the noise resistance so as to eliminate this drawback, it is effective to use an optical fiber. Since an optical fiber cannot connect a plurality of light receiving modules to one optical fiber in a multi-drop manner like an electric cable, each of the optical fiber and the control device 11 is different from the conventional power conversion system 10 shown in FIG. The power converters 12-1 to 12-4 are connected one-to-one by a bidirectional optical fiber 14, and a pulse on / off signal is transmitted. Each of the power conversion devices 12-1 to 12-4 is connected to a drive load device 14 such as a large-capacity power supply device or a motor drive device.

  However, in this system, since it is necessary to route the optical fibers 13 for the number of power conversion devices 12-1 to 12-4 connected from the control device 11, a necessary number of optical transmission modules are mounted on the control device 11. However, the power converters 12-1 to 12-4 that are centrally installed apart from the control device 11 must be wired with many optical fibers 13. For this reason, there exists a fault that wiring space increases.

  In order to solve this disadvantage, it is conceivable to connect the control device and a plurality of power conversion devices in a ring shape with an optical fiber and relay data sequentially. However, if the received transmission signal is transmitted to the next as it is, transmission distortion due to the optical fiber transmission line and optical / electrical / electrical / optical signal conversion means accumulates in the transmission signal and causes a reception error downstream in the transmission line. Become.

  For this reason, the control device and each power conversion device employ a regenerative relay system in which received data is once reconstructed as digital data and then transmitted. In this regenerative relay system, data is transmitted and received by a transmission clock signal generated in each device, and at the timing when the device transmits data by the transmission clock signal, the data to be transmitted next is upstream. It receives from the side device.

As this kind of conventional power converters, there are ones described in Patent Documents 1 and 2, for example.
Japanese Patent No. 2501173 Japanese Patent No. 3227533

  However, in the above-described conventional regenerative relay system, the next data to be transmitted from the upstream device is received at the timing when the own device transmits data due to the difference in the transmission clock signal between the upstream device and the own device. This is not possible, and tooth loss occurs in the transmission data downstream. In this case, for example, “0”, which is different from the original “1”, is inserted into the missing portion, and a group of data including this portion is determined as an error by the error correction processing and discarded as a transmission error. Become.

  In the power conversion system, when the data in which the transmission error has occurred is the control data from the control device, the same control data is received by all the power conversion devices necessary for controlling the drive load device. Therefore, it becomes impossible to synchronize the switching operation between the power converters. In this case, there is a problem that a current or voltage having a predetermined waveform cannot be supplied from each power conversion device, and the drive load device cannot be appropriately controlled.

  The present invention has been made in view of such a problem, and when data is sequentially regenerated and relayed by connecting a plurality of devices having a communication function with optical fibers, each device properly transmits and receives data, To provide an optical transmission device and a power conversion device that can synchronize the control timing based on the received data in each device, and thereby can appropriately drive and control the drive load device with a plurality of devices. It is aimed.

  In order to achieve the above object, an optical transmission apparatus according to claim 1 of the present invention is connected to relay an optical signal to a round-trip optical transmission line that is turned back at the most downstream position, and receives the optical signal that is relayed. In an optical transmission device that regenerates data and then converts it to an optical signal and transmits it while temporarily storing and reading it in the order of reception, the time when the downstream optical signal going downstream is received, and the received optical signal is transmitted. Then, when returning after being returned at the most downstream side, the measuring means for measuring the difference time from the time when the return optical signal was received, and the self-light by dividing the difference time measured by the measuring means by 2 The synchronization time is determined by obtaining the most downstream arrival time from the transmission device to the most downstream optical transmission device, and using either the most downstream arrival time or a time obtained by adding a certain time to the most downstream arrival time as a synchronization timing time. It is characterized in that a ring generator.

  According to this configuration, each optical transmission device that regenerates and repeats an optical signal obtains the most downstream arrival time from the own optical transmission device to the most downstream optical transmission device, and is constant in the most downstream arrival time and the most downstream arrival time. Since either one of the times added to the time is set as the synchronization timing time, in all the optical transmission devices that perform regenerative relay, the time when the synchronization timing time has elapsed from the time when each received the optical signal It can be the same time.

  For example, when the first, second, third, and fourth optical transmission devices are connected in order from upstream to downstream, and the fourth optical transmission device is the most downstream, the most downstream arrival time (= synchronization timing time) However, it is assumed that the first optical transmission device is 5 minutes, the second optical transmission device is 3 minutes, and the third optical transmission device is 1 minute. The citation time is a time for giving priority to easy understanding of the explanation.

  Assuming that the time when the optical signal is received by the first optical transmission device is 1:00, the time when the most downstream arrival time has elapsed from this time 1:00 is 1:05. Since the optical signals are sequentially transmitted downstream, the optical signal reception time is 1:02 in the second optical transmission device, and the time when 3 minutes of the most downstream arrival time has elapsed from this time 1:02 is 1: 2. 05. In the third optical transmission apparatus, the reception time of the optical signal is 1:04, and the time when one minute of the most downstream arrival time has elapsed from this time 1:04 is 1:05. In the most downstream optical transmission apparatus, the reception time is 1:05.

  For this reason, for example, in a system in which a plurality of independent control devices simultaneously control devices to be controlled, each control device includes an optical transmission device, and each control device performs synchronization timing from the reception time of the optical signal in the optical transmission device. If the control based on the data by the received optical signal is executed at the time when the time has elapsed, it becomes possible to control the control target device at the same time.

The power conversion device according to claim 2 of the present invention is a power conversion device that is connected to a plurality of round-trip optical transmission lines that are turned back at the most downstream side and controls the device to be controlled by the plurality of power conversion devices. When the data by the optical signal received by the optical transmission device is control data, the optical transmission device can obtain the control data from the reception time of the control data. The control target device is controlled based on the control data at the time when the synchronization timing time has elapsed.
According to this configuration, the plurality of power conversion devices execute control based on the control data on the control target device at the time when the synchronization timing time has elapsed from the reception time of the control data by the optical signal in the optical transmission device. The control target device can be controlled at the timing when the plurality of power conversion devices are synchronized.

  As described above, according to the present invention, when a plurality of devices having communication functions are connected by optical fibers and data is sequentially regenerated and relayed, each device properly transmits and receives data, and control based on the received data It is possible to synchronize timing with each device, and this has the effect that the drive load device can be appropriately driven and controlled by a plurality of devices.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment)
FIG. 1 is a block diagram showing a configuration of a power conversion system according to an embodiment of the present invention.
In the power conversion system 20 illustrated in FIG. 1, a control device 21 and a plurality of power conversion devices 22-1 to 22-4 are connected by a bidirectional optical fiber 23. In this connection, as shown in FIG. 2, the downstream data D1 transmitted from the upstream device (control device 21) to the optical fiber 23 is sequentially relayed by the power conversion devices 22-1 to 22-3, and the most downstream power is transmitted. When it reaches the conversion device 22-4, it is looped back and relayed as uplink data D2 in the reverse order to the downlink and returned to the control device 21.

  The control apparatus 21 gives the switching command for on / off control of the switching element with which the said power converter device is provided with respect to each power converter device 22-1 to 22-4. In response to this command, a voltage or current having a predetermined waveform is supplied from each of the power conversion devices 22-1 to 22-4 to the drive load device 14 such as a multiphase motor or a power supply system. Here, only one drive load device 14 is described, but a plurality of drive load devices 14 may be provided.

The power converters 22-1 to 22-4 include an optical transmission unit 25, a converter control unit 26, and a converter main circuit unit 27, as representatively shown in FIG. It is prepared for.
The optical transmission unit 25 performs regenerative relay of data using an optical signal via the optical fiber 23 between the control device 21 that is an upstream device and another power conversion device 22-2 that is a downstream device. Among these, the data received from the control device 21 is a command value (also referred to as a drive command value) for driving the power conversion device 22-1 so as to output a voltage or current having a predetermined waveform to the drive load device 14. . The transmission data to the control device 21 is status information inside each power conversion device 22-1 to 22-4.

In addition, the optical transmission unit 25 is a synchronization timing time signal for synchronizing the switching control timing of the converter main circuit unit 27 performed by the converter control unit 26 in all the power conversion devices 22-1 to 22-4. Is generated and output to the converter control unit 26.
As shown in FIG. 4, the configuration of the optical transmission unit 25 includes O / E (optical / electrical) module units 41 and 48, E / O (electrical / optical) module units 42 and 47, and FIFO ( First-In First-Out) memory units 45 and 50, DPLL (Digital Phase-Locked Loop) units 43 and 49, data reception unit 44, transmission time measurement unit 51, data transmission unit 52, and synchronization timing generation And a portion 53. Such components will be described.

The O / E module unit 41 converts the optical signal from the upstream device transmitted through the optical fiber 23 into an electrical signal, and the O / E module unit 48 is transmitted through the optical fiber 23. The optical signal from the downstream device is converted into an electric signal.
The E / O module unit 42 converts an electrical signal into an optical signal and transmits the optical signal to an upstream device via the optical fiber 23. The E / O module unit 47 converts the electrical signal into an optical signal. The optical signal is transmitted to the upstream device via the optical fiber 23.

The DPLL unit 43 or 49 generates a clock signal for data capture timing from the electrical signal converted by the O / E module 41 or 48, and outputs this clock signal and received data synchronized with the clock signal. Is.
The FIFO memory unit 45 or 50 temporarily stores the reception data reproduced by the DPLL unit 43 or 49 in the order of input, and outputs the stored reception data in the order of input. This temporary storage includes the length of the optical fiber 23 between the power converters 22-1 to 22-4 and the transmission clock signal caused by the O / E module units 41 and 48 and the E / O module units 42 and 47. Absorbs the deviation.

  As described in the above-mentioned “Problem to be Solved by the Invention”, this is the timing at which the device transmits data due to a slight shift in the transmission clock signal (shift in the transmission clock signal with the upstream device). This is to prevent a transmission error caused by a state in which data to be transmitted next from the upstream device cannot be received. In other words, the FIFO memory units 45 and 50 perform temporary storage for absorbing and eliminating data transmission / reception timing shifts of all the power conversion devices 22-1 to 22-4 and the control device 21.

  The data receiving unit 44 reads the received data from the DPLL unit 43 according to the clock signal sent together with the received data, and decodes the read data according to the transmission data format shown in FIG. As a result of the decoding, when it is confirmed that there is no transmission error, the command value data from the control device 21 is output to the converter control unit 26.

  Here, the transmission data format is a format of data transmitted to the optical fiber 23 and conforms to a format called HDLC (High-level Data Link Control procedure). As shown by reference numeral 61 in FIG. 5A, a series of data transmitted through the optical fiber 23 can be identified by being sandwiched by a specific pattern called a FLAG (flag) (for example, 01111110 as a bit pattern). It has become.

The transmission data is transmitted by a signal encoding method called NRZI (Non Return to Zero Inversion). NRZI is a method of transmitting by changing the signal according to the rule that it does not change when the data is “0” but changes when it is “1”, and the polarity of the data is reversed at the time of reception. However, there is an advantage that the same information can be obtained.
If five “1” s continue in the data before encoding, then “0” is inserted and data processing is performed so that six or more “1s” do not continue. This process prevents the transmission signal level flowing through the transmission line from being changed regardless of the transmission of any kind of data from continuing for 6 or more sections, and corrects the received signal timing at the signal change point of the DPLL unit 43. It is guaranteed that the operation will be executed at a certain frequency.

Further, by this encoding method, the FLAG pattern 61 in which six “1” s are continuous does not appear in the data, and the first and last data strings can be identified. The address information 62 is information for identifying the device that transmitted the data.
The control drive command / status information number 63 includes first to nth (fourth in this example) drive command values 63-1 to 63-4 from the control device 21 to the power converters 22-1 to 22-4. The status request power conversion number 63-S, which is the identification number of the corresponding power conversion devices 22-1 to 22-4, which is added when the internal status is transmitted after receiving the data sequence at the end of the data sequence. Yes.

  A CRC (Cyclic Redundancy Check) code 64 is a code for detecting a transmission error between the address information 62 and the control drive command / status information 63, and is obtained by performing a specific operation on the data string. . The power converters 22-1 to 22-4 that have received the data obtain a CRC value by performing a CRC operation on the received data string, and confirm that there is no transmission error in the received data by comparison with the received CRC value. It has become.

  Next, the transmission time measuring unit 51 will be described with reference to the flowchart of FIG. When the transmission time measuring unit 51 detects the FLAG pattern 61 of the downlink data D1 from the DPLL unit 43 in step S1, in step S2, the transmission time measuring unit 51 performs a counting operation using a clock signal input together with the downlink data D1 (see FIG. Start counting. In step S3, when the FLAG pattern 61 of the upstream data D2 is detected from the DPLL unit 49, the counting of the counter is stopped in step S4. In step S6, a transmission time corresponding to the count value at the time of the stop is obtained.

  That is, the count value is the same as that when the own power conversion device 22-1 receives the downlink data D1 from the control device 21, and the downlink data D1 is transmitted. As shown in FIG. It is the transmission time Td until it is returned at -4. A half of the transmission time Td is a time (also referred to as a most downstream arrival time) for the downlink data D1 to reach the most downstream power conversion device 22-4 from the own power conversion device 22-1.

  Here, since the transmission time Td is different for each of the power conversion devices 22-1 to 22-4, the transmission time measured by the transmission time measuring unit 51 of the power conversion device 22-1 in order from the upstream side is expressed as Td1. The transmission time measured by the transmission time measurement unit 51 of the power conversion device 22-2 is Td2, and the transmission time measured by the transmission time measurement unit 51 of the power conversion device 22-3 is Td3. Since the power converter 22-4 is the most downstream, the transmission time is 0 (none).

The synchronization timing generation unit 53 obtains the most downstream arrival time Td / 2 by dividing the transmission time Td measured by the transmission time measuring unit 51 by 2, and the most downstream arrival time Td / 2 is measured next. The time Td is held until it is input, and the held most downstream arrival time Td / 2 is supplied to the converter controller 26 as a synchronization timing time signal.
Based on the command value from the data reception unit 44 and the synchronization timing time signal from the synchronization timing generation unit 53, the converter control unit 26 sends a gate signal for turning on / off the switching element to the converter main circuit unit 27. Output. Further, the state of the power conversion device 22-1 is monitored, and status information is transmitted to the optical transmission unit 25 in response to a command from the control device 21.

  Here, the converter main circuit unit 27 will be described. The converter main circuit unit 27 outputs a voltage or current having a predetermined waveform to the drive load device 14 by turning on / off the switching element in accordance with the gate signal from the converter control unit 26. At this time, the operation of the switching element is protected according to the characteristics of the switching element, for example, by giving a certain delay to the on-time or preventing the on-time from becoming smaller than the set minimum time. A configuration example in the case where the converter main circuit unit 27 is a three-phase motor drive control circuit is shown in FIG. 7 and will be described.

The converter main circuit unit 27 includes a diode rectifier 31 that converts a three-phase AC power source into a DC, an inductor 32, a capacitor 33, and IBGT (Insulated Gate Bipolar Transistor) elements 34a and 34b that switch the three-phase DC. And an inverter main circuit 34 composed of 34c, 34d, 34e, and 34f.
A gate signal for controlling switching of the IGBT elements 34a to 34f is supplied as an on / off signal from the converter control unit 26, and a three-phase signal having a predetermined waveform is supplied from an inverter main circuit 34 which performs an on / off operation in response to the supply. A voltage or current signal is output to the drive load device 14.

The on / off operation of the IGBT elements 34a to 34f will be further described with reference to FIG. However, in FIG. 8, a pair of 34a and 34b is representatively shown among the IGBT elements 34a to 34f.
The gates of the IGBT elements 34a to 34f are controlled to be turned on / off by the upper arm gate signal P1 and the lower arm gate signal P2 of the constant converter control cycle C1 generated by the converter control unit 26.

  The drive command value from the control device 21 represents the ratio of the on-pulse section H1 to the converter control cycle C1. For example, when the drive command value is 50, an on-pulse of 50% of the converter control cycle C1 is generated. In addition, a certain time difference is provided so that the ON sections of the upper arm gate signal P1 due to the ON pulse and the lower arm gate signal P2 due to the ON pulse do not overlap, so that a short circuit due to simultaneous ON of the upper and lower arm gate signals P1 and P2 is prevented. It has become.

Further, the converter control unit 26 operates so that the changing point of the converter control cycle C <b> 1 matches the timing according to the synchronization timing time signal from the synchronization timing generation unit 53. That is, if the synchronization timing time signal is a signal indicating the most downstream arrival time Td1 / 2, the converter receives the time when the most downstream arrival time Td / 2 has elapsed from the time when the drive command value is received by the data receiving unit 44. Control is performed so that the changing points of the control cycle C1 are matched.
Thus, in the converter control part 26 of all the power converter devices 22-1 to 22-4, if the change point of the converter control cycle C1 is matched with the instruction | indication timing of a synchronous timing time signal, all the power converter devices 22- It is possible to perform a switching operation in which 1 to 22-4 are synchronized.

The reason for this will be described with reference to FIG. However, the unit of the transmission time Td quoted in this description is for easy understanding of the description, and is different from the actual unit.
Further, the most downstream arrival time Td1 / 2 from the power converter 22-1 is 5 minutes, the most downstream arrival time Td1 / 2 from the power converter 22-2 is 3 minutes, and the most downstream from the power converter 22-3. The arrival time Td1 / 2 is assumed to be 1 minute.
If the command value 63-1 from the control device 21 is received at the time t1 (10:00), the converter control unit 26 of the most upstream power conversion device 22-1 will start from the reception time 1:00. Control is performed so that the changing point of the converter control cycle C1 matches the time 1:05 when 5 minutes of the downstream arrival time has elapsed.

If the command value 63-2 is received at time t2 (1:02), the converter control unit 26 of the power conversion device 22-2 has passed 3 minutes from the reception time 1:02. At time 1:05, control is performed so that the changing point of the converter control cycle C1 is matched.
If the command value 63-3 is received at time t2 (1:04), the converter control unit 26 of the power conversion device 22-3 has passed one minute of the most downstream arrival time from the reception time 1:04. At time 1:05, control is performed so that the changing point of the converter control cycle C1 is matched.

If the command value 63-2 is received at the time t2 (1:05), the converter control unit 26 of the most downstream power converter 22-4 receives the converter control cycle C1 at the reception time 1:05. Control so that the change points of
Thus, since all the power converters 22-1 to 22-4 are controlled so that the changing point of the converter control cycle C1 matches at time 1:05, all the power converters 22-1 to 22-4 are synchronized. Switching operation is performed.

However, instead of the most downstream arrival time Td / 2, a certain time may be added to the most downstream arrival time Td / 2, and the time after this addition may be used.
If the converter control unit 26 determines that there is a request for transmission of status information from the control device 21 to the own device, the converter control unit 26 receives the data from the control device 21 and then ends the transmission switching unit 46. In response to this, a switching signal from the relay operation of received data to the transmission operation of own device data is output. Thereafter, the status information is sent to the data transmission unit 52, converted into an optical signal by the E / O module unit 47, and transmitted to the next power conversion device via the optical fiber 23. However, the converter control unit 26 may be disposed in the optical transmission unit 25.

Control for driving the drive load device 14 in the power conversion system 20 having such a configuration will be described.
First, when control data based on an optical signal from the control device 21 is transmitted to the nearest power conversion device 22-4 via the optical fiber 23, the O / E module unit 41 of the power conversion device 22-1 It is converted into an electric signal and output to the DPLL unit 43. In the DPLL unit, a clock signal for data capture timing is generated from the electrical signal, and this clock signal and control data reproduced in synchronization with the clock signal are transmitted to the FIFO memory unit 45, the data receiving unit 44, and the transmission. It is output to the time measuring unit 51.

  In the FIFO memory unit 45, the reproduced received data is stored in the order of input, and the stored control data is output to the E / O module unit 47 via the transmission switching unit 46 in the order of input. It is converted and transmitted to the next power converter 22-2 via the optical fiber 23. Such optical signal regenerative relay processing is also performed in the other power converters 22-2 to 22-4, and is returned by the most downstream power converter 22-4 and regenerated and relayed as an upstream optical signal in the same way as downstream. Finally, it is transmitted to the control device 21.

  On the other hand, in the process of sequentially reproducing and relaying the optical signal in this way, processing for obtaining and holding the most downstream arrival time Td / 2 is performed. That is, when the transmission time measuring unit 51 detects the FLAG pattern 61 of the downlink control data, the counting operation is started. Thereafter, the control data is turned back at the most downstream power converter 22-4 and returned as uplink control data. When the FLAG pattern 61 is detected, the count operation is stopped, and the count value at the time of the stop is transmitted. The time Td1 is output to the synchronization timing generator 53.

Similarly, the transmission times Td2 and Td3 are measured and output to the synchronization timing generation unit 53 in the power conversion devices 22-2 and 22-3 other than the most downstream power conversion device 22-4.
The synchronization timing generation unit 53 obtains the most downstream arrival time Td / 2 that is ½ of the transmission time Td1, and until the most recently measured transmission time Td1 is input. Retained. The held most downstream arrival time Td / 2 is supplied to the converter control unit 26 as a synchronization timing time signal.

On the other hand, when the data receiving unit 44 confirms that there is no transmission error in the control data from the DPLL unit 43, the command value 63-1 from the control device 21 in the control data is converted to the converter control unit 26. Is output.
The converter control unit 26 generates upper and lower arm gate signals P1 and P2 in synchronization with the converter control cycle C1 based on the command value 63-1. At this time, the changing point of the converter control cycle C1 at which the changing points of the upper and lower arm gate signals P1, P2 are synchronized is controlled based on the synchronization timing time signal.

  That is, at the time (1:05) when the most downstream arrival time Td1 / 2 (= 5) has elapsed from the time (1:00) when the command value 63-1 was received by the data receiving unit 44, the converter control cycle C1. It is controlled so that the change points of Also in this downstream power converter 22-2, converter control is performed at time 1:05 when the most downstream arrival time Td2 / 2 (= 3) has elapsed from time (1:02) when the command value 63-2 is received. Control is performed so that the changing points of the cycle C1 are matched, and the downstream power converter 22-3 also has the most downstream arrival time Td3 / 2 (= 1) from the time (1:04) when the command value 63-3 is received. ) Is controlled so that the changing point of the converter control cycle C1 matches at time 1:05. The most downstream power converter 22-4 is controlled so that the changing point of the converter control cycle C1 matches the time (1:05) when the command value 63-4 is received.

By this control, in all the power converters 22-1 to 22-4, the changing point of the converter control cycle C1 is matched at time 1:05.
As a result, the switching operation of the converter main circuit unit 27 by the gate signal of the converter control unit 26 of the total power conversion devices 22-1 to 22-4 is synchronized, so that a voltage or current having a predetermined waveform is applied to the drive load device 14. Is output.

  As described above, in the power conversion system 20 according to the present embodiment, a plurality of power conversion devices 22-1 to 22-4 are connected to an optical transmission line formed by a round-trip optical fiber 23 that is turned back at the most downstream position. The drive load device 14 is controlled by the power conversion devices 22-1 to 22-4. In this case, when the data by the optical signal from the control device 21 sequentially received by the optical transmission unit 25 of each power conversion device 22-1 is control data, each of the power conversion devices 22-1 to 22-4. The drive load device 14 is controlled based on the control data at the time when the synchronization timing time signal obtained by the optical transmission unit 25 has elapsed from the reception time of the control data in the optical transmission unit 25.

  Accordingly, data is properly transmitted and received by the optical transmission unit 25 of each power conversion device 22-1 to 22-4, and control timing synchronization based on this received data is synchronized by each power conversion device 22-1 to 22-4. Thus, the drive load device can be appropriately driven and controlled by the plurality of power conversion devices 22-1 to 22-4.

It is a block diagram which shows the structure of the power conversion system which concerns on embodiment of this invention. It is a figure for demonstrating the flow of the data to the transmission line connected to the ring shape of the power conversion system which concerns on the said embodiment. It is a block diagram which shows the structure of the power converter device of the power conversion system which concerns on the said embodiment. It is a block diagram which shows the structure of the optical transmission part in the said power converter device. (A) is the transmission data format figure of the data transmitted to the optical fiber of the power conversion system which concerns on the said embodiment, (b) is a figure which shows the structure content of the control drive command / status number information shown to (a). is there. It is a flowchart for demonstrating the measurement process of the transmission time in the transmission time measurement part in the optical transmission part of the said power converter device. It is a figure which shows the structure of the converter main circuit part in the said power converter device. It is a figure for demonstrating the switching operation | movement of the converter main circuit part by the converter control part of the said power converter device. It is a timing chart for demonstrating the synchronization alignment of the switching operation in the said power converter device. It is a block diagram which shows the structure of the conventional power conversion system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 Drive load apparatus 20 Power conversion system 21 Control apparatus 22-1 to 22-4 Power conversion apparatus 23 Bidirectional optical fiber 25 Optical transmission part 26 Converter control part 27 Converter main circuit part 31 Diode rectifier 32 Inductor 33 Capacitor 34a , 34b, 34c, 34d, 34e, 34f IGBT element 41, 48 O / E module section 42, 47 E / O module section 45, 50 FIFO memory section 43, 49 DPLL section 44 Data receiving section 51 Transmission time measuring section 52 Data Transmission unit 53 Synchronization timing generation unit 61 FLAG pattern 62 Address information 63 Control drive command / status information number 63-1 to 63-4 First to fourth drive command values 63-S Status required power conversion number 64 CRC code

Claims (2)

It is connected so as to relay the optical signal to the round-trip optical transmission line that is turned back at the most downstream, receives the relayed optical signal, reproduces the data, and then stores it in the receiving order and converts it into an optical signal while reading it. In an optical transmission device that transmits
Measures the time difference between the time when the downstream optical signal going to the most downstream is received and the time when the received optical signal is sent back after being sent back at the most downstream side. Measuring means to
The difference time measured by the measuring means is divided by two to obtain the most downstream arrival time from the own optical transmission device to the most downstream optical transmission device, and a certain time is set for the most downstream arrival time and the most downstream arrival time. An optical transmission apparatus comprising: synchronization timing generation means that uses any one of the added times as a synchronization timing time. In a power converter that is connected to a plurality of reciprocating optical transmission lines that are turned back at the most downstream side and controls a device to be controlled with the plurality of optical transmission lines,
An optical transmission device according to claim 1,
When the data by the optical signal received by the optical transmission device is control data, the time when the synchronization timing time obtained by the optical transmission device has elapsed from the reception time of the control data by the optical transmission device In addition, a control based on the control data is executed on the control target device.

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