JP5910694B2 - AC rotating machine control device - Google Patents

Description

  The present invention relates to a control device for an AC rotating machine, and more particularly to a control device for an AC rotating machine having a communication function with an information device attached with a power conversion device that drives a plurality of AC rotating machines at a predetermined speed.

  A power conversion system that operates a plurality of AC rotating machines with a plurality of inverter devices (power converters) generally instructs the upper speed control device to instruct or monitor the rotational speed of the AC rotating machine as a target value. It can be constructed as a system equipped with a master device. In such a power conversion system for operating an AC rotating machine, if the inverter device of a plurality of AC rotating machines is constructed as an information linkage system connected by a communication line using optical communication etc., the AC rotating machine will be abnormal. Before becoming, appropriate control becomes possible based on the current and the current information detected by the inverter device.

FIG. 6 is a system configuration diagram illustrating an example of a conventional power conversion system.
This power conversion system realizes synchronized operation, ratio operation, and operation / stop control of a plurality of AC rotating machines M1 to M3 by the host controller 10. Here, a PLC (Programmable Logic Controller) or a personal computer is used as a master station. In addition, a plurality of power converters 11 to 13 having the same function for driving the AC rotating machines M1 to M3 are connected to the host controller 10 as slave devices through the same communication line 21.

  Here, for example, an optical fiber or the like is used for the communication line 21, and each of the power conversion devices 11 to 13 is connected to the host control device 10 via a bidirectional module. Further, accessory devices such as the temperature sensor 14 and the pressure sensor 15 are also connected as slave stations, and necessary information can be given to the host control device 10 through the communication line 21.

  In the conventional power conversion system, the host controller 10 centrally manages information from the attached devices such as the power converters 11 to 13 and the temperature sensor 14 via the communication line 21, and a plurality of power converters that are slave devices. Various commands such as an operation / stop command and a speed command were given to 11 to 13 while judging the situation individually. Therefore, in the host control device 10, when a disconnection occurs in the communication line 21 connecting the power conversion devices 11 to 13, it is necessary to perform a protective operation such as stopping the output. Therefore, when communication from the master station becomes impossible due to disconnection of the communication line 21 connecting the master station and the slave station or a failure of the communication control device, it can be automatically restored. It was not possible and the system was not stable.

  In addition, operation commands and speed commands for the power converters 11 to 13 do not pass through a communication line, and are based on an operation command based on an external digital on / off signal or a speed command based on an external analog voltage (current) input command. Sometimes transmitted. Even in such a case, it is necessary to share information for predictive maintenance and the like based on temperature and inverter current information before the machine becomes abnormal.

  As another power conversion system, from a power unit consisting of a power supply unit and a power conversion unit, from an application unit and a motor control unit that can be customized by connecting a combination of multiple execution codes, functions, and blocks built in beforehand with parameters Input / output of a plurality of inverter devices having the same function in an inverter composed of a control unit composed of an execution code unit and a CPU (Central Processing Unit) that executes the execution code, and an external communication interface unit Are connected by communication, and each inverter device is assigned as a master station and a slave station (see Patent Document 1 below).

  Here, one of the plurality of inverter devices having the same function serves as a master station, and writing (Read) data or reading (Read) data is transferred to the remaining inverter devices. Therefore, a small-scale system can be realized without using an expensive PLC or communication control option card.

JP 2008-178236 A

  However, in the device described in Patent Document 1, accessory devices such as temperature sensors other than a plurality of inverter devices cannot be connected to the same communication line. Therefore, a plurality of pieces of information obtained from various accessory devices cannot be used for controlling an AC rotating machine operated by an inverter device as a slave station via a communication line.

  In addition, information from inverter devices having different functions (for example, speed detection, timepiece, etc.) cannot be exchanged with other inverter devices on the same communication through the master station. For this reason, there is a problem that information from other inverter devices cannot be used in common for controlling an AC rotating machine.

  Furthermore, when the inverter device that constitutes the master station becomes unable to communicate due to disconnection of the communication line or failure of the control device, it cannot be automatically restored, and it is not easy to link between the plurality of inverter devices. There was also a problem.

  The present invention has been made in view of the above points, and by sharing information among a plurality of power conversion devices and other accessory devices, and strengthening the drive linkage of the AC rotating machine, the power conversion system It is an object of the present invention to provide a control device for an AC rotating machine that facilitates overall optimization.

  Another object of the present invention is to provide an AC rotating machine control device that can constitute a power conversion system that can be automatically restored even when communication is disabled due to a disconnection or failure of the communication line. It is.

  In order to solve the above problems, the present invention provides a control device for an AC rotating machine having a communication function between a plurality of power conversion devices that drive the AC rotating machine at a predetermined speed and an attached information device. . In the control device for the AC rotating machine, the plurality of power conversion devices have different functions, and the plurality of power conversion devices and the information device are connected to each other. Communication means for maintaining cooperation is provided.

  In the control device for the AC rotating machine, one of the power conversion devices is designated as a master station, and the control state information each of the power conversion devices having different functions and the control state information of the information device have Is shared among all the power converters.

  According to the present invention, when a plurality of power converters are controlled and operated in cooperation, information is shared with a plurality of AC rotating machine driving power converters and other devices through a communication function, thereby strengthening the linkage. Can optimize the entire system.

It is a block diagram which shows the power conversion system which concerns on Embodiment 1 of this invention. It is a time chart which shows the timing of the information transmission between a master apparatus and a slave apparatus. It is a block diagram which shows the power conversion system which concerns on Embodiment 2 of this invention. It is a figure which shows the communication protocol for the information transmission between a master apparatus and a slave apparatus. It is a flowchart which shows an example of the judgment procedure for switching of a master apparatus. It is a system configuration figure showing an example of the conventional power conversion system.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
1 is a block diagram showing a power conversion system according to Embodiment 1 of the present invention.

  The power conversion system includes a host control device 10, a plurality of power conversion devices 11 to 13, and attached information equipment. The host controller 10 gives various commands such as an operation / stop command and a speed command to the power converters 11 to 13 or monitors the states of the power converters 11 to 13 and the AC rotating machines M1 to M3. Do. The power converters 11 to 13 control the speed of the AC rotating machines M1 to M3, respectively. Here, the attached information devices are assumed to be various sensor devices such as a temperature sensor 14 and a pressure sensor 15 provided in a load such as a pump driven by the AC rotating machines M1 to M3. The power conversion devices 11 to 13 have different functions. For example, the power conversion device 12 is equipped with a speed or position detection function, and the power conversion device 13 is equipped with a clock function. .

  The host control device 10 is connected to the power conversion device 11 set as the master station and the power conversion device 12 set as the master station candidate by the first communication line 22, and the host control device 10 and the specific power Signals are exchanged with the converters 11 and 12. Furthermore, the power converters 11 and 12 have two or more communication functions, and the remaining power converter 13, various sensor devices such as the temperature sensor 14 and the pressure sensor 15, and the host controller 10 are not interposed. Connected by the second communication line 23, and exchanges signals between the power converters 11 to 13 and with sensor devices such as the temperature sensor 14 and the pressure sensor 15.

  That is, only the two power converters 11 and 12 connected to the host controller 10 via the first communication line 22 can be master stations. In addition, the second communication line 23 that is different from the first communication line 22 and not including the host controller 10 is used to connect the power converters 12 and 13 constituting the slave stations 1 and 2 to each other and the temperature sensor 14. The pressure sensor 15 is connected to each other and the mutual cooperation is maintained. As a result, distributed control for a plurality of AC rotating machines M1 to M3 is possible, and efficient information transmission between the attached information devices, that is, the temperature sensor 14 and the pressure sensor 15, without passing through the host controller 10 is possible. Become. Furthermore, it is possible to share information such as speed detection values and clocks from the power converters 12 and 13 having different functions (speed detection function, clock function, etc.) among all the power conversion apparatuses 11 to 13. Become.

  In the first embodiment, a power conversion system that does not include information devices such as the temperature sensor 14 and the pressure sensor 15 may be used. For example, only the power converters 11 to 13 having different functions are connected by the second communication line 23, and each information such as a speed detection value and a clock that each of the power converters 11 to 13 has is obtained. The power converters 11 to 13 may be shared.

  Here, the power converters 11 and 12 include communication modules necessary for connection to the first and second communication lines 22 and 23, respectively. Further, the power converters 12 and 13 include a communication module required for connection with the second communication line 23. The first and second communication lines 22 and 23 are both configured by optical cables or the like, and transmit / receive other signals including a control signal in addition to a failure signal.

  In the configuration of the conventional power conversion system shown in FIG. 6, the power conversion devices 11 to 13 and the host control device 10 are connected by only one line 21 having the same communication function, and a plurality of power conversions This is different from the above-described first embodiment in that the devices 11 to 13 all have the same function.

  In the system configuration of the first embodiment described above, a digital interface (DI / DI) for inputting a digital signal from the outside of the power converters 11 to 13 for driving the AC rotating machines M1 to M3 or outputting a digital signal to the outside. DO) or analog interface (AI / AO) for inputting analog signals from outside or outputting analog signals to the outside, and control status information including clock function, speed, position, etc. can be shared Therefore, it is possible to keep the power conversion device that is more functional and expensive than the conventional device to the minimum necessary. In addition, it is possible to optimize the entire system by keeping the communication option card or the like to the minimum necessary. In the power conversion devices 11 to 13, linked operation such as ratio operation that can be adapted for decentralization with the host control device 10. Becomes easier.

  Furthermore, when the power conversion device 11 set as the master station becomes unable to communicate due to disconnection of the first communication line 22 or failure of the communication module, it is designated in advance as a candidate for the next master station. The power converter 12 can be switched to a new master station. Therefore, it is possible to automatically recover without damaging the linked operation of the entire system.

FIG. 2 is a time chart showing the timing of information transmission between the master device and the slave device.
FIG. 2A shows information transmission timing (part 1) between the master station and the slave station. Normally, control signals CT1, CT2, and CT3 are supplied as periodic commands from the master station to the slave station, and response signals CR1, CR2, and CR3 to the master station corresponding to the signals CT1, CT2, and CT3 from the slave station. The necessary data has been sent. The response signals CR1, CR2, and CR3 include data that always needs to be read from the master station, such as speed data and power consumption data. Here, the communication line 23 is assumed to be a half-duplex communication system, but the slave station and the master station may be connected by a full-duplex communication line.

  In addition to the predetermined periodic command, the master station between the power converter 11 serving as a master station, the power converters 12 and 13 serving as slave stations, and the attached information devices (temperature sensor 14 and pressure sensor 15). From the power converter 11, a command corresponding to the interrupt processing by a failure detection signal or the like is sent as a single command to the power converters 12, 13, the temperature sensor 14, and the pressure sensor 15, which are slave stations. Processed as INT. At that time, the slave station returns a response signal ICR to the master station with respect to the operation command, the speed command, and the read / write command for each function.

  FIG. 2B shows information transmission timing (part 2) between the master station and the slave station. Normally, the control signals CT1 to CT4 are supplied as periodic commands from the master station to the slave station, and necessary data are transmitted from the slave station as response signals CR1 to CR4 to the master station corresponding to the signals CT1 to CT4. Has been. The response signals CR1 to CR4 include data that always needs to be read from the master station, such as speed data and power consumption data. Here, the communication line 23 shown in FIG. 1 is assumed as a half-duplex communication system, but the slave station and the master station may be connected by a full-duplex communication line.

  Between the power conversion device 11 and the power conversion device 12, in addition to a predetermined periodic command, an abnormal command corresponding to a failure detection signal or the like is sent as a single command from the power conversion device 11 that is a master station. , It is processed as an interrupt signal INT by the power converter 12 which is a slave station.

  In addition to the predetermined periodic command, the master station between the power converter 11 serving as a master station, the power converters 12 and 13 serving as slave stations, and the attached information devices (temperature sensor 14 and pressure sensor 15). From the power conversion device 11, a command corresponding to the interrupt processing by a failure detection signal or the like is broadcasted as a broadcast signal, and the power conversion devices 12 and 13 that are slave stations and associated information devices (temperature sensor 14, pressure sensor 15). And processed as an interrupt signal INT, and the same data such as an operation command and a speed command from the master station is written to the slave station.

  2B shows that the interrupt signal INT is transmitted simultaneously from the master station by the broadcast method and written to all slave stations, whereas FIG. 2A shows the interrupt signal INT. Based on INT, the master station writes / reads data to / from each slave station.

(Embodiment 2)
FIG. 3 is a block diagram showing a power conversion system according to Embodiment 2 of the present invention.
This power conversion system includes power conversion devices 11 to 13 that control the speeds of the AC rotating machines M1 to M3, and attached information devices. The power conversion devices 11 to 13 have different functions, for example, the power conversion device 12 is equipped with a speed or position detection function, and the power conversion device 13 is equipped with a clock function or the like. Here, the attached information devices are assumed to be various sensor devices such as a temperature sensor 14 and a pressure sensor 15 provided in a load such as a pump driven by the AC rotating machines M1 to M3. The communication line 24 connects the three power converters 11 to 13 and the temperature sensor 14 and the pressure sensor 15 attached to the AC rotating machines M1 to M3 to each other. Mutual cooperation is maintained.

  The power converters 11 to 13, the temperature sensor 14, and the pressure sensor 15 include a communication module required for connection to the communication line 24. Moreover, the power converters 11 and 12 are provided with a communication module. Here, among the power converters 11 to 13, for example, the power converter 11 is designated as a master station, and the remaining power converters 12 and 13, the temperature sensor 14, and the pressure sensor 15 are slave stations. Further, a power conversion device (for example, power conversion device 12) to be a next master station candidate is set in advance from among the power conversion devices 12 and 13 set as slave stations. Thereby, it becomes possible to share necessary operation control information among all the power converters and the temperature sensor 14 and the pressure sensor 15. Furthermore, it is possible to share information such as speed detection values and clocks from the power converters 12 and 13 having different functions (speed detection function, clock function, etc.) among all the power conversion apparatuses 11 to 13. Become.

  In the second embodiment, a system that does not include information devices such as the temperature sensor 14 and the pressure sensor 15 may be used, and only the power converters 11 to 13 having different functions are connected via the communication line 24. Thus, the power detection devices 11 to 13 may share information such as speed detection values and clocks among all the power conversion devices 11 to 13. Here, the communication line 24 is configured by an optical cable or the like, and transmits and receives other signals including a control signal in addition to a failure signal.

  In the system configuration of the second embodiment described above, the digital interface (DI / DO) and analog interface (AI / AO) of the power converters 11 to 13 that drive the AC rotating machines M1 to M3, the clock function, Control state information including speed and position can be shared, and a high-performance and expensive power conversion device can be minimized as compared with the conventional device. Further, by keeping the communication option card or the like to the minimum necessary, the entire system can be optimized, and linked operation such as ratio operation suitable for decentralization can be easily performed among the power conversion devices 11 to 13.

  In addition, when the power conversion device 11 set as the master station becomes unable to communicate with the slave station due to disconnection of the communication line 24 or failure of the communication module, the power specified in advance as a candidate for the master station The conversion device 12 can be switched to a new master station. Therefore, it is possible to automatically recover without damaging the linked operation of the entire system.

Furthermore, the master AC rotating machine driving power converter is automatically recoverable even when communication becomes impossible due to a disconnection or failure of the communication line.
Note that the timing of information transmission between the master device and the slave device is the same as that in FIGS. 2A and 2B described above, and a description thereof will be omitted here.

FIG. 4 is a diagram illustrating a communication protocol for information transmission between the master device and the slave device.
FIG. 2A shows a communication protocol for information transmission from the master station to the slave station, and FIG. 2B shows a communication protocol for information transmission from the slave station to the master station.

  Here, the station number stored in the address 00h (and 00H) is a number for identifying one slave station from a plurality of slave stations (that is, the power converters 11 to 13, the temperature sensor 14, and the pressure sensor 15). It is.

  The FC stored at the address 01h (and 01H) means a function code for identifying various functions on the same communication line 22-24. Thus, even when slave stations that do not have the same function are connected on the same communication lines 22 to 24, application of the function can be identified only between devices having the same function.

The operation commands at addresses 02h and 03h and the frequency settings at addresses 04h and 05h mean operation commands and frequency commands from the master station to the slave stations.
In the address 06h, an address where polling function data is stored, that is, a polling function address is arranged. Here, the polling function refers to various functions that the master station can read from the slave station (Read).

  In the address 07h, an address storing the selecting function data, that is, a selecting function address (08h, 09h) is arranged. Here, the selecting function refers to various functions that the master station can write to the slave station. Therefore, selecting function data is stored at addresses 08h and 09h, respectively.

  In the protocol of FIG. 4B, the operation state monitor of AC rotating machine M2 is stored at addresses 02H and 03H. Further, the operation state monitor of the AC rotating machine M3 is stored at addresses 04H and 05H. Furthermore, output frequency monitors are stored at addresses 06H and 07H. These operation state monitor, output frequency monitor, and the like mean monitor data from the slave station to the master station.

A switching (Chg) signal and an error code are stored at address 08H. These signals are signals that function as a switching command from the slave station to the master station.
At address 09H, an address storing polling function data, that is, polling function addresses (0AH, 0BH) is arranged corresponding to address 06h. Therefore, actual polling function data is stored in addresses 0AH and 0BH, respectively.

FIG. 5 is a flowchart illustrating an example of a determination procedure for switching the master device.
Here, the determination procedure executed in the slave station (power converter 12) in standby as the next master station in the first and second embodiments shown in FIGS. 1 and 3 is shown.

  In step S1, it is determined whether or not the communication state with the master station is normal. That is, if a periodic command is received from the master station (power converter 11) to the power converter 12, it is determined that the communication state with the master station is normal, and the process proceeds to step S5. On the other hand, when the power conversion device 11 as the first master station becomes unable to communicate due to a disconnection of the communication line or a failure of the communication module, the cycle from the master station (power conversion device 11) to the power conversion device 12 is cycled. The command is not received and the process proceeds to the next step S2.

  In step S2, counting is started by the monitoring timer of the slave station, and the process proceeds to next step S3. In step S3, the presence / absence of a command signal from the master station is determined within a predetermined time. If there is no command signal from the power converter 11 as the master station within this fixed time, which is measured by the monitoring timer, it is determined that there is an abnormality, and the process proceeds to step S4. Then, the master station switching process is executed, and the standby slave station (power converter 12) is set as a new master station as the next master station.

  If it is determined in step S1 that the communication state with the master station is normal, and if the master station switching process is executed in step S4, the process proceeds to steps S5 and S6, respectively, and the monitoring timer of the slave station is cleared. Return to step S1.

  If the command signal from the master station is communicated within a certain time measured by the monitoring timer in step S3, the process for the new determination procedure is started as it is (step S1).

  As described above, in the method for operating an AC rotating machine according to the present invention, the standby slave station (power converter 12) can be automatically switched to the master station. As the method, the next master station (power converter 12) always monitors the state of the first master station (power converter 11), and there is no command signal from the master station (power converter 11) for a certain period of time. For example, the next master station (power converter 12) is caused to function as a master station. After that, when avoidance from the communication disabled state is realized in the first master station (power conversion device 11), the power conversion device 11 becomes a slave station, and the master station (power conversion device 12) of the master station (power conversion device 12) only for a certain period of time. The communication state is monitored, and if there is no communication, it is determined that there is no new master station (power converter 12), and the first master station (power converter 11) returns to the master station again.

DESCRIPTION OF SYMBOLS 10 High-order control apparatus 11-13 Power converter 14 Temperature sensor (attached apparatus)
15 Pressure sensor (accessory equipment)
22 First communication line 23 Second communication line 24 Communication line

Claims (3)

In a control device for an AC rotating machine having a communication function between a plurality of power converters that drive the AC rotating machine at a predetermined speed and an attached information device,
The plurality of power conversion devices have different functions,
A communication means for maintaining mutual cooperation by mutually connecting the plurality of power conversion devices and between the information devices and the information devices;
While designating any one of the power converters as a master station, the control state information possessed by the power converters having different functions and the control state information possessed by the information equipment are all between the power converters A control device for an AC rotating machine, which is shared by all. In a controller for an AC rotary machine having a communication function between a plurality of power conversion devices for driving the ac rotating machine at a predetermined speed,
The plurality of power conversion devices have different functions,
Comprising communication means for connecting the plurality of power converters to each other and maintaining mutual cooperation;
An alternating current characterized in that any one of the power conversion devices is designated as a master station, and control state information of each of the power conversion devices having different functions is shared among all the power conversion devices. Control device for rotating machine. A plurality of power conversion devices are specified in advance as candidates for the master station, and the power conversion device designated as the master station communicates with the remaining power conversion devices by the communication means. 3. The control device for an AC rotating machine according to claim 1, wherein when the power conversion device becomes impossible, one of the remaining power conversion devices is switched as a master device. 4.

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