JP2002345256A - Servo control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a servo control device capable of reducing the cost of the device more without using any unnecessary circuit device at the time of accommodating networks and constituting a network drive. SOLUTION: In constituting a digital input servo which receives a digital command by connecting with a host controller by one to one with a main circuit module 100 and a device net interface module 200, a CPU 102 and a drive circuit (ASIC) 103 are provided in the main circuit module 100 as a circuit part for performing servo computation and generating a gate drive signal GD, and data such as a phase command and control information are received and sent between the main circuit module 100 and the device net interface module 200 through a serial interface 106, a serial signal line cable 150, and a serial interface 204 by means of high-speed serial transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo control device which comprises an inverter in which upper and lower semiconductor switches of each phase are bridge-connected, and controls the speed or position of a motor to be controlled by opening and closing each semiconductor switch of the inverter. In particular, the present invention relates to a servo control device that can construct a system without having unnecessary circuit elements when supporting a device net or configuring a network drive, and further reduces the device cost.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram of a conventional servo control device for device nets (first conventional example). Referring to FIG. 4, the servo control device of the first conventional example includes a main circuit module 500, an optional device network interface module 600, and a control circuit module 700, and controls the speed and position of a motor 511 to be controlled. The control is performed. Each module is configured as a substrate. The motor 511 driven at a variable speed is additionally provided with an encoder 512 as means for detecting a rotation speed and a position.
The main circuit module 500 includes a converter 501 and a CPU.
502, three-phase inverter 504, interface 506
And a current detection resistor 507.
Also, the device net interface module 600
Are the device net interface unit 601, the CPU 6
02 and a two-port RAM 603. Further, the control circuit module 700 includes an AD converter 701, a CPU 702, and a control circuit (ASIC) 70.
3, a parameter switch and an LED 704, and an interface 705. First, considering a configuration including only the main circuit module 500 and the control circuit module 700 (in the configuration, the device net interface module 600 is not connected), in this case, an analog speed command is given to the control circuit module 700, and the AD converter After being converted into a digital speed command by 701, the digital speed command is read by the CPU 702, and a calculation result by a predetermined calculation is supplied to the control circuit (ASIC) 703, and each of the U-phase, V-phase, and W-phase of the three-phase inverter 504 is A gate drive signal GD for on / off control of the upper and lower power transistors is generated. Gate drive signal G generated by control circuit (ASIC) 703
D is supplied to the three-phase inverter 504 of the main circuit module 500 via the isolator of the interfaces 705 and 506. The current, voltage, and the like detected by the current detection resistor 507 and the like of the main circuit module 500 are taken into the CPU 502 and reflected in current control and the like. However, the CPU 502 and the CPU 702 are connected by a serial interface. Information such as current and voltage is input to the CPU 702 of the control circuit module 700 via the isolators of the interfaces 506 and 705, and is reflected in speed control, vector control, and the like. The speed or position detection information from the encoder 512 attached to the motor 511 is input to the control circuit (ASIC) 703 of the control circuit module 700, and is provided for feedback control. In addition, regarding the parameter setting of the motor control performed in the control circuit module 700, input and output (confirmation) are performed by the parameter switch and the LED 704, and the control circuit (ASI
C) An analog monitor output can be obtained from 703. Next, a configuration in which an optional device net interface module 600 is added will be considered. In the device network interface module 600, when a digital speed command is read by the CPU 602 via the device network interface unit 601, a calculation result of a predetermined calculation is written to the two-port RAM 603. On the other hand, the CPU 702 of the control circuit module 700 can access the two-port RAM 603 via a signal line (including a data bus, an address bus, and a control signal group) 650, and the two CPUs 602 and 702 are connected by the two-port RAM 603. Configuration. next,
FIG. 5 shows a configuration diagram of a conventional servo control device having a network drive configuration (second conventional example). In FIG. 5, the second
The conventional servo control device includes a main circuit module 500
And the mechatronic link interface module 800
And a control circuit module 700. The main circuit module 500, the control circuit module 700, the motor 511 and the encoder 512 to be controlled are the same as those in the first conventional example (see FIG. 4). In the network drive configuration, when the mechatronic link interface module 800 is one slave station and the upper controller is the master station, the master station and N (N is a positive integer) slave stations are connected in a multi-drop connection in a 1: N relationship. Is done. In this case, each lower-level controller, which is a slave station,
The operation of the master station (upper controller) is controlled by the data transmitted from the upper controller as the master station. The master station (upper controller) sends a control command to each slave station (lower controller) via the network transmission line 850,
Request the required data. The mechatronic link interface module 800 includes a mechatronic link interface unit 801, a CPU 802, and a two-port RAM 803. In the mechatronic link interface module 800, when a speed command from the network 850 is read into the CPU 802 via the mechatronic link interface unit 801, a calculation result by a predetermined calculation is written to the two-port RAM 803. On the other hand, the CPU 702 of the control circuit module 700 includes a signal line (including a data bus, an address bus, and a control signal group) 75
0 can access the 2-port RAM 603, and the two CPUs 602 and 702
This is a configuration connected by M603.

[0003]

However, in the above-described conventional servo control device, the configuration of the main circuit module 500 and the control circuit module 700 is originally
Since it is configured to accept analog commands from the outside with an analog interface as standard, it is connected to a host controller in a one-to-one manner to receive digital commands, and a network drive connected in a one-to-N multidrop connection. In order to achieve this, an optional module is added, and when the optional module is mounted, a circuit portion for an analog interface has a useless configuration. Further, in the conventional servo controller, as the interfaces 506 and 705 between the main circuit module 500 and the control circuit module 700, there are a gate drive signal GD, a detected current, a voltage, and the like. Therefore, an isolator for insulation is required for the number of signals. The present invention has been made in view of the above-mentioned conventional circumstances, and has a configuration in which a digital command is received in a one-to-one connection with a higher-level controller.
Even in the case of a network drive configuration with multi-drop connection to the N, a servo controller with excellent cost performance by minimizing signal isolation isolators by using a serial interface without wasteful circuit parts. It is intended to provide.

[0004]

According to a first aspect of the present invention, there is provided a servo control apparatus comprising: an inverter in which upper and lower semiconductor switches of each phase are bridge-connected; A drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter is generated based on an internal phase command based on a position feedback from the detecting means or a current feedback from the current detecting means, or based on an external phase command. A main circuit module comprising: a drive signal generation unit; a first interface unit for performing serial transmission of the phase command or control information in the main circuit module with another module via a serial transmission path; Second interface means for receiving a speed command, and the main circuit module based on the speed command. Control means for determining a phase command for the module, and third interface means for performing serial transmission of the phase command or control information in the main circuit module with the main circuit module via the serial transmission path. And a circuit module. According to a second aspect of the present invention, in the servo controller according to the first aspect, the second interface means converts a speed command from a higher-order controller into a digital signal. According to a third aspect of the present invention, in the servo controller according to the first or second aspect, the control circuit module is installed in a higher-level control unit together with another control circuit module. Furthermore, the servo control device according to claim 4 is an inverter in which upper and lower semiconductor switches of each phase are bridge-connected, and an internal motor based on position feedback from position detection means attached to the motor or current feedback from current detection means. A drive signal generating means for generating a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter based on a phase command or an external speed command; and the speed command or control information in the main circuit module. , A first interface means for performing serial transmission with another module via a serial transmission path;
Is a positive integer), and the N main circuit modules are 1
The main control modules are connected in a one-to-N multidrop connection.

[0005] In the servo control device according to the first and third aspects of the present invention, the main circuit module includes an inverter, a drive signal generating means and a first interface means, and the control circuit module includes a second interface means and a control means. And a third interface means, respectively, and when a speed command is received from a higher-level controller via the second interface means in the control circuit module,
The control means determines a phase command for the main circuit module based on the speed command, and the drive signal generation means in the main circuit module determines the phase command based on the position feedback from the position detection means attached to the motor or the current feedback from the current detection means. Based on an internal phase command or an external phase command, a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter is generated. Thus, even when the digital controller is configured to receive a digital command by being connected to the host controller in a one-to-one manner, there is no needless circuit portion unlike the related art. Further, since the first and third interface means transmit the phase command from the outside or the control information in the main circuit module to the control circuit module via the serial transmission line, the signal insulation isolators can be reduced as much as possible. Thus, a servo control device excellent in cost performance can be realized. In the servo control device according to claims 2 and 3 of the present invention,
The main circuit module includes an inverter, a drive signal generating unit, and a first interface unit. The control circuit module includes a second interface unit, a control unit, and a third interface unit. (2) When a speed command from the host controller is received via the interface means and converted into a digital signal, the control means determines a phase command for the main circuit module based on the speed command, and the drive signal generation means in the main circuit module determines the phase command. Controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter based on an internal phase command based on a position feedback from a position detecting means attached to the motor or a current feedback from a current detecting means, or based on an external phase command. Generate a drive signal. Accordingly, in a case where a one-to-one connection with an upper-level controller is made to receive an analog command, the first and third interface means transmit a phase command from the outside or control information in the main circuit module to a serial transmission path. Since the serial transmission with the control circuit module is performed via the control circuit, a servo control device excellent in cost performance can be realized by minimizing the signal isolation isolator. Further, in the servo control device according to claim 4, the main circuit module is provided with an inverter, a drive signal generating means, and a first interface means, and the N main circuit modules are composed of one main control module and one main control module. In the configuration of the network drive multi-drop-connected to the N, an internal phase command based on the position feedback from the position detection means attached to the motor or the current feedback from the current detection means by the drive signal generation means in the main circuit module, Alternatively, based on an external speed command,
A drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter is generated. As a result, even in the case of a configuration of a network drive connected in a one-to-N multi-drop connection, there is no needless circuit portion unlike the related art. In addition, since the first interface means performs serial transmission of a speed command from the outside or control information in the main circuit module with the main control module via a network, the signal insulation isolators are reduced as much as possible and the cost performance is excellent. Servo control device can be realized.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a servo control device according to the present invention will be described with reference to the drawings in the order of [first embodiment], [second embodiment], and [third embodiment]. And will be described in detail. [First Embodiment] FIG. 1 is a block diagram of a servo control device according to a first embodiment of the present invention. In FIG. 1, a servo control device according to the present embodiment includes a main circuit module 100
And a device net interface module 200 for controlling the speed and position of the motor 111 to be controlled. Each module is configured as a substrate. The motor 111 driven at a variable speed is additionally provided with an encoder 112 as a means (position detecting means) for detecting a rotational speed and a position. The main circuit module 100 includes a converter 101, a CPU 102, and a drive circuit (ASIC).
103, a three-phase inverter 104, a serial interface 106, and a current detection resistor 107. The device net interface module 200 includes a device net interface unit 201,
It comprises a CPU 202, a control circuit (ASIC) 203, and a serial interface 204. Here, the CPU 102 and the drive circuit (ASIC) 1
03 is an internal phase command based on position feedback from an encoder 112 attached to the motor 111 or current feedback from a current detection resistor 107, or
Based on the phase command from the device network interface module 200, the U-phase and V-phase of the three-phase inverter 104
It corresponds to a drive signal generating means for generating a gate drive signal GD for controlling on / off of the upper and lower power transistors of each phase of the phase and the W phase. Also, serial interface 1
06 is the device net interface module 20
The phase command from 0 or the control information in the main circuit module 100 corresponds to first interface means for performing high-speed serial transmission via the serial signal line cable 150. Also, the device net interface unit 2
01 corresponds to a second interface unit that receives a speed command from a host controller, and the CPU 202 and the control circuit (ASIC) 203 correspond to a control unit that determines a phase command to the main circuit module 100 based on the speed command. The serial interface 204 receives a phase command or control information in the main circuit module 100,
This corresponds to third interface means for performing high-speed serial transmission via the serial signal line cable 150. The serial interface 106 and the serial interface 204 are isolated by a pulse transformer or the like. The servo control device according to the present embodiment converts the output of the commercial power supply into DC by the converter 101, converts the DC voltage into three-phase AC of U-phase, V-phase and W-phase by the three-phase inverter 104, The speed control or the position control of the motor 111 to be controlled is performed by driving using a so-called inverter control method that generates a driving voltage. As the inverter control method, a voltage control type inverter or a PWM control type inverter is applicable. Three-phase inverter 104
Has a configuration in which power transistors are respectively provided as upper and lower semiconductor switches in each of the U-phase, V-phase, and W-phases, and these are bridge-connected. The three-phase inverter 104
Since the output voltage is a rectangular wave, a feedback diode for processing regenerative energy or reactive power is added to each power transistor. The semiconductor switches that constitute the three-phase inverter 104 include a bipolar power transistor and a GTO (Gate Turn Off Thyr).
istor), IGBT (Insuated Gate Bipolar Transisto)
r), Power MOSFET (PowerMetal Oxide Semicond)
uctor Field Effect Transistor) can be applied. The servo control device according to the present embodiment is configured to receive a digital command by being connected to a higher-level controller on a one-to-one basis. First, when a digital speed command is given to the device net interface module 200, the servo control device is connected via the device net interface unit 201. A digital speed command is read by the CPU 202, and a phase command for the main circuit module 100 is determined by the CPU 202 and the control circuit (ASIC) 203 based on the digital speed command, and the serial interface 204, the serial signal line cable 150 and the serial interface 106 are determined. Is supplied to the drive circuit (ASIC) 103 via the.
In the CPU 102 and the drive circuit (ASIC) 103, the gate drive signal GD based on the internal phase command based on the position feedback from the encoder 112 or the current feedback from the current detection resistor 107 or the phase command from the device net interface module 200. And supplies the gate drive signal GD to the three-phase inverter 104 to turn on / off the upper and lower power transistors of each of the U, V, and W phases.
As described above, in the servo control device of the present embodiment, when the main circuit module 100 and the device net interface module 200 have a digital input servo configuration that is connected to the host controller in a one-to-one manner and receives a digital command, the first Unlike the conventional example (see FIG. 4), there is no needless circuit portion such as an analog command input system. Further, as a circuit part for performing a servo operation and generating a gate drive signal GD, a CPU 102 and a drive circuit (ASI
C) The high-speed serial transmission and reception of data such as phase commands and control information between the main circuit module 100 and the device net interface module 200 via the serial interface 106, the serial signal line cable 150, and the serial interface 204. Therefore, as compared with the first conventional example (see FIG. 4), the isolation of signal insulation can be reduced to one portion of the communication portion, the number of circuit components can be reduced, and the cost performance is excellent. A servo control device can be realized.

[Second Embodiment] FIG. 2 is a configuration diagram of a servo control device according to a second embodiment of the present invention. 2, a servo control device according to the present embodiment includes a main circuit module 100 and an analog interface module 30.
The main circuit module 100, the motor 111 to be controlled, and the encoder 112 are the same as those in the first embodiment (see FIG. 1). The analog interface module 300 includes an AD converter 301, a CPU 302, a control circuit (ASIC) 303,
It comprises a parameter switch and LED 304 and a serial interface 305. Here, the AD converter 301 corresponds to a second interface unit that receives a speed command from a higher-order controller and converts it into a digital signal, and the CPU 302 and the control circuit (ASIC) 303 send a command to the main circuit module 100 based on the speed command. The serial interface 305 corresponds to third interface means for performing high-speed serial transmission of the phase command or control information in the main circuit module 100 via the serial signal line cable 150. The servo control device according to the present embodiment is configured to receive an analog command by being connected to a higher-level controller on a one-to-one basis. First, when an analog speed command is given to the analog interface module 300, the analog converter 300 converts the analog speed command into a digital speed command. After being converted, it is read by the CPU 302,
The CPU 302 and the control circuit (ASIC) 303 determine a phase command to the main circuit module 100 based on the speed command, and
The drive circuit (ASIC) 10 via the serial signal line cable 250 and the serial interface 106
3 is supplied. CPU 102 and drive circuit (A
The SIC 103 generates a gate drive signal GD based on an internal phase command based on the position feedback from the encoder 112 or the current feedback from the current detection resistor 107 or a phase command from the analog interface module 300 to generate a three-phase signal. Inverter 1
04 to the U-phase, V
The on / off control of the upper and lower power transistors of each of the phase and the W phase is performed. As described above, in the servo control device of the present embodiment, when the main circuit module 100 and the analog interface module 300 have an analog input servo configuration that is connected to the upper-level controller in a one-to-one manner and receives an analog command, the servo calculation is performed. As a circuit portion for generating the gate drive signal GD, the CPU 102 and the drive circuit (A
(SIC) 103 is mounted, and data transmission such as phase command and control information between the main circuit module 100 and the analog interface module 300 is performed by serial transmission via the serial interface 106, the serial signal line cable 250, and the serial interface 305. Therefore, as compared with the first conventional example (see FIG. 4),
The number of signal isolation isolators can be reduced to one, the number of circuit components can be reduced, and a servo control device excellent in cost performance can be realized.

[Third Embodiment] FIG. 3 is a block diagram of a servo control device according to a third embodiment of the present invention. In FIG. 3, the servo control device of the present embodiment includes a main circuit module 100, and includes a main circuit module 10
The motor 111 and the encoder 112 to be controlled are the same as those in the first embodiment (see FIG. 1).
The servo control device of the present embodiment uses N (N is a positive integer) main circuit modules 100 as slave stations, and one main control module (not shown; corresponds to the above-described upper-level controller) as a master station. In this case, a network drive configuration is formed by multi-drop connection of 1: N. In this case, each main circuit module 100 as a slave station is controlled in operation by data and commands sent from a higher-level controller as a master station. The main control module (master station) sends a control command or the like to each main circuit module 100 via the network transmission line 350 to request necessary data. C in the main circuit module 100
In the PU 102 and the drive circuit (ASIC) 103, an internal phase command based on the position feedback from the encoder 112 or the current feedback from the current detecting resistor 107, or the speed from the main control module received via the serial interface unit 106 A gate drive signal GD is generated based on the command, and the gate drive signal GD is supplied to the three-phase inverter
The on / off control of the upper and lower power transistors of each of the phase, V phase and W phase is performed. As described above, in the servo control device according to the present embodiment, even when the network drive is configured to have a one-to-N multi-drop connection, the mechatronic link interface module 800 and the control unit are controlled as in the second conventional example (see FIG. 5). There is no option module such as the circuit module 700. In addition, the first interface means performs serial transmission of the speed command from the main control module or the control information in the main circuit module 100 with the main control module via the network transmission line 350. ), The number of signal isolation isolators can be reduced to one, the number of circuit components can be reduced, and a servo control device excellent in cost performance can be realized.

[0009]

As described above, according to the servo controller of the present invention, the main circuit module is provided with the inverter, the drive signal generating means and the first interface means,
The control circuit module further includes a second interface unit,
An internal phase command based on a position feedback from a position detector attached to the motor or a current feedback from a current detector by a drive signal generator in the main circuit module. Alternatively, a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter is generated based on an external phase command, so that the digital signal and the analog command are connected one-to-one with the host controller. Even in the case of a configuration for accepting, there is no needless circuit portion unlike the related art, and the first and third circuits are not required.
The interface means performs serial transmission of the external phase command or control information in the main circuit module to the control circuit module via the serial transmission line. A control device can be provided. Further, according to the servo control device of the present invention, the main circuit module is configured to include the inverter, the drive signal generating means, and the first interface means, and the N main circuit modules are connected to one main control module and one main control module. In the configuration of the network drive multi-drop-connected to the N, an internal phase command based on the position feedback from the position detection means attached to the motor or the current feedback from the current detection means by the drive signal generation means in the main circuit module, Alternatively, based on an external speed command,
Since a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter is generated, even in the case of a network drive configuration in which 1-to-N multi-drop connections are made, useless circuit parts as in the related art are eliminated. No serial communication is performed with the main control module via the network for external speed commands or control information in the main circuit module by the first interface means. Thus, a servo control device excellent in cost performance can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a servo control device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a servo control device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a servo control device according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional device-compatible servo control device (first conventional example).

FIG. 5 is a configuration diagram of a conventional network drive configuration servo controller (second conventional example).

[Explanation of symbols]

100, 500 Main circuit module 101, 501 Converter 102, 502 CPU 103 Drive circuit (ASIC) 104, 504 Three-phase inverter 106, 204, 305 Serial interface 506, 705 interface 107, 507 Current detection resistor GD Gate drive signal 111, 511 Motor 112, 512 Encoder 150, 250, 350 Serial signal line cable 200, 600 Device net interface module 201, 601 Device net interface unit 202, 602, 802 CPU 203 Control circuit (ASIC) 603, 803 2-port RAM 650, 750 Signal line 300 analog interface module 700 control circuit module 301, 701 AD converter 302, 02 CPU 303,703 control circuit (ASIC) 304,704 parameter switches and LED 800 Mechatronics link interface module 801 Mechatronics link interface unit 350,850 network transmission path

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H007 AA05 BB06 CA01 CB05 CC23 DA03 DB01 DB07 DC04 DC07 EA08

Claims (4)

[Claims] An inverter in which upper and lower semiconductor switches of each phase are bridge-connected, and an internal phase command based on a position feedback from a position detecting means attached to the motor or a current feedback from a current detecting means, or
A drive signal generating means for generating a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter based on an external phase command; and a serial transmission path for the phase command or control information in the main circuit module. A first interface unit for performing serial transmission with another module via the main circuit module; a second interface unit for receiving a speed command from a higher-level controller; and a phase for the main circuit module based on the speed command. A control circuit module comprising: control means for determining a command; and third interface means for performing serial transmission of the phase command or control information in the main circuit module with the main circuit module via the serial transmission path. And a servo control device. 2. The servo control device according to claim 1, wherein said second interface means converts a speed command from a host controller into a digital signal. 3. The servo control device according to claim 1, wherein the control circuit module is installed in a higher control unit together with another control circuit module. 4. An inverter in which upper and lower semiconductor switches of each phase are bridge-connected, and an internal phase command based on position feedback from position detection means or current feedback from current detection means attached to the motor, or
A drive signal generating means for generating a drive signal for controlling the opening and closing of the upper and lower semiconductor switches of each phase of the inverter based on a speed command from the outside; and a serial transmission path for the speed command or control information in the main circuit module. N (where N is a positive integer) including first interface means for performing serial transmission with another module via N. The N main circuit modules include one main control module and one main control module. A servo control device, which is connected in a one-to-N multi-drop connection.