JPH06141550A - Inverter and motor control system - Google Patents

Abstract

PURPOSE:To allow drive control of a plurality of motors without requiring inverters for individual motors by separating a power converting means from an inverter control means and communicating data between them through a duplex serial communication line. CONSTITUTION:A host controller 8 outputs positional command signals P1a, P1b, P1c, designating target positions of induction motors 1a, 1b, 1c, through a communication interface 75. A position control section 71 outputs speed command signals T1a, T1b, Ti1c depending on the difference between the positional command signals P1a, P1b, P1c and current positional signals Pa, Pb, Pc fed from a positional sensor converting circuit 72. An each shaft inverter control circuit 73 delivers the speed command signals T1a, T1b, T1c and a control signal corresponding to the set value in a parameter setting section 74 through serial communication interfaces 6, 34a, 34b, 34c to inverter circuits 33a, 33b, 33c in power converting means 3a, 3b, 3c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter device for performing variable speed control and positioning control of a motor and a motor control system using the same.

[0002]

2. Description of the Related Art Recently, a motor control system in which an induction motor and an inverter device are combined in a one-to-one relationship has come to be used as a driving means for positioning in an automation system or the like. FIG. 5 is a diagram showing a schematic configuration of a motor control system when positioning control of an induction motor using a conventional inverter device.

The induction motor (IM) 1 is a three-phase drive type motor. A rotary position sensor 2 for detecting the current position of the induction motor 1 is coupled to the rotary shaft of the induction motor 1. The output P0 of the rotational position sensor 2 is taken into the position sensor conversion circuit 62. The position control means 4 is composed of a position control unit 61 and a position sensor conversion circuit 62. The position sensor conversion circuit 62 converts the output P0 of the rotational position sensor 2 into current position data P2 and outputs it to the position control unit 61. The position control unit 61 inputs the position command data P1 indicating the target position of the induction motor 1 from a host controller (not shown), and the current position data P indicating the current position of the induction motor 1.
Enter 2 and. The position control unit 61 uses the position command data P1
Between the current position data P2 and the current position data P2 is obtained, and a speed command signal T1 corresponding to the position deviation is output to the inverter control circuit 34 of the inverter device 3.

The inverter device 3 is roughly divided into a power conversion section for converting a DC drive current into an AC drive current having a predetermined frequency according to a control signal, and a current control section for driving and controlling a power device in the power conversion section. It The power conversion unit includes a converter circuit 31, a voltage control circuit 32, and an inverter circuit 33, and the current control unit includes an inverter control circuit 34.

The converter circuit 31 receives a three-phase AC voltage (R phase, S phase, T phase) from the external power source 5 via the electromagnetic contactor 51.
Phase) and converts it into a predetermined DC drive current.
The voltage control circuit 32 does not extract a part of the DC voltage converted by the converter circuit 31 as a power supply voltage and supplies it to the inverter control circuit 34, or the DC voltage does not exceed a predetermined value due to regenerative energy during braking. Or, it is constantly monitored whether or not the DC voltage falls below a predetermined value due to the voltage drop of the external power supply 5. Then, the voltage control circuit 32
Outputs an overvoltage signal or a voltage drop signal to the inverter control circuit 34 when the DC voltage is equal to or higher than a predetermined value or is equal to or lower than a predetermined value.

The inverter circuit 33 includes a voltage control circuit 32.
DC voltage input via the inverter control circuit 34
It is converted into a three-phase AC voltage (U-phase, V-phase, W-phase) having a frequency in a predetermined range (about 360 Hz) based on the control signal from and is supplied to the induction motor 1. Parameter setter 4
Performs setting of operation / function of the inverter device 3, monitoring of operating status, display of abnormality content, and the like. Parameter setter 4
Inverter control circuit 3 sets various parameters set in
4 is stored in the memory.

The inverter control circuit 34 receives the parameters from the parameter setter 4 and the speed command signal T1 from the position controller 61, outputs control signals corresponding to them to the inverter circuit 33, and outputs the control signal of the induction motor 1. Controls rotation speed, etc. That is, the inverter control circuit 34 is
The power transistor in the inverter circuit 33 is driven by the M signal, and each phase (U phase, V phase, W) of the induction motor 1 is driven.
Phase) by supplying a driving current of a predetermined frequency to
The rotation speed of the induction motor 1 is controlled.

At this time, the current feedback signal T2 detected by the current detection isolator CT is fed back to the inverter control circuit 34. The inverter control circuit 34 monitors, based on the current feedback signal T2, whether or not the overcurrent exceeds the rated output current.
Further, the inverter control circuit 34 includes the converter circuit 31.
When the DC voltage is out of the predetermined range, that is, when an overvoltage signal, a voltage drop signal, or the like is input from the voltage control circuit 32, it operates as a protection circuit for stopping the operation of the inverter device 3.

[0009]

In the motor control system as described above, it is necessary to provide the induction motor 1 with the inverter device 3 corresponding thereto one by one, and when the induction motor 1 is replaced, the inverter device 3 is replaced. The device 3 also had to be replaced with a corresponding one. Further, in general, the inverter device 3 and the position control means 6 are usually provided for each induction motor, so that even when a plurality of shafts (induction motors) are controlled in the same manner, they are controlled separately. Even in this case, the parameter setter 4 had to be connected to the inverter control circuit 34 of each axis to set the parameters. Further, even when controlling a plurality of axes, it is necessary to provide an inverter device for each induction motor of each axis, which is wasteful in terms of cost, and there is a problem that the entire system becomes large.

The present invention has been made in view of the above points, and provides an inverter device and a motor control system capable of drive control even when controlling a motor having a plurality of axes without providing an inverter device for each motor. The purpose is to provide.

[0011]

The inverter device of the present invention has a power conversion means for converting a DC drive current into an AC drive current of a predetermined frequency in accordance with a control signal, a speed command signal, and a parameter set therein. Accordingly, in an inverter device comprising an inverter control means for outputting the control signal to the power conversion means, the power conversion means and the inverter control means are separated into separate units, and data transmission between them is performed. Is performed by a bidirectional serial communication line.

A motor control system of the present invention is provided in each of a plurality of motors and the plurality of motors, and converts a DC drive current into an AC drive current of a predetermined frequency according to a control signal input from the outside. A plurality of power conversion means for supplying to the motor, a position sensor provided in each of the plurality of motors for detecting a signal indicating the current position of the motor, a speed command signal input from the outside and an internal Inverter control means for outputting the control signal to each of the plurality of power conversion means via a bidirectional serial communication line in accordance with the set parameter;
Parameter setting means for changing the setting of the parameters, a position command signal indicating the target position of the motor and a signal indicating the current position of the motor are input, and the speed command signal based on these signals is input to the inverter control means. To a host controller for outputting the position command signal and the parameter for controlling the rotation of the motor, and the position command signal connected to the host controller via a second communication line. To the position control means and communication means for outputting the parameters to the parameter setting means.

[0013]

In the inverter device of the present invention, the power conversion means and the inverter control means are separated and each is constituted by a separate unit, and the data transmission between the two is performed by a bidirectional serial communication line. Therefore, the power conversion means for controlling the high current and high voltage can be arranged close to the motor or the like, while the inverter control means composed of the logic circuit or the like can be installed with a certain distance from the motor or the like. Therefore, the logic circuit in the inverter control means is not affected by the noise generated in the power conversion means, and the malfunction of the logic circuit is reduced. Also, since the power conversion means controls high current and high voltage, there are more failures than the inverter control means, so only the power conversion means needs to be replaced at the time of failure, and the parameters etc. in the inverter control means need to be replaced again. You don't have to set it. Furthermore, since the operating speed of the inverter control means is much higher than that of the power conversion means, one inverter control means can control a plurality of power conversion means.

In the motor control system of the present invention, the power conversion means is provided in each of the plurality of motors,
The plurality of power conversion means are controlled by one inverter control means and one position control means via a bidirectional serial communication line. Further, the host controller controls the rotation speeds of a plurality of motors only by outputting the position command signal and the parameter for controlling the rotation of each motor to the position control means and the parameter setting means by the communication means. You can Also,
Even if the rating of the motor or the power converting means is changed, it is possible to promptly respond to the change of the motor or the like only by changing and setting the parameters according to the changed rating of the motor or the power converting means.

[0015]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing an embodiment of a motor control system according to the present invention. In the present embodiment, the three induction motors 1 using the inverter device according to the present invention are used.
A motor control system for controlling a, 1b and 1c will be described.

The induction motors (IM) 1a, 1b and 1c are, for example, three-phase AC drive type motors. Each induction motor 1
Rotational position sensors 2a, 2b and 2c for absolutely detecting their current positions are coupled to the rotational shafts a, 1b and 1c, respectively. As the rotational position sensors 2a, 2b and 2c, for example, JP-A-57-70 is used.
An inductive type phase shift type position sensor as shown in Japanese Patent No. 406 is used. Rotational position sensors 2a, 2b and 2
The respective outputs Pa, Pb and Pc of c are fetched by the position sensor conversion circuit 72 in the position control means 7.

The position control means 7 is composed of a position control unit 71, a position sensor conversion circuit 72, each axis inverter control circuit 73, a parameter setting unit 74 and communication interfaces 75 and 76. Each axis inverter control circuit 73, the parameter setting unit 74, and the communication interfaces 75 and 76 are a part of the inverter device of the present invention, and the power converter 3
It is an inverter control means mainly composed of a logic circuit, which is separated from each of a, 3b and 3c.

The position sensor conversion circuit 72 converts the respective outputs Pa, Pb and Pc of the rotational position sensors 2a, 2b and 2c into digital position data P2a, P2b and P2c and outputs them to the position controller 71. Communication interface 7
Reference numeral 5 connects the external host controller 8 to the position control unit 71 and the parameter setting unit 74 via a communication line (for example, RS232C, RS422, or PLC link), and transmits / receives data between them.

The position controller 71 inputs position command data P1a, P1b and P1c indicating the target positions of the induction motors 1a, 1b and 1c transmitted from the host controller 8 via the communication interface 75, and guides them. The current position data Pa, Pb and Pc indicating the current positions of the electric motors 1a, 1b and 1c are input. And
The position control unit 71 controls the position command data P1a, P1b and P1.
1c and the current position data Pa, Pb, and Pc are respectively obtained, and the speed command signal T corresponding to the position deviation is obtained.
1a, T1b and T1c are connected to each axis inverter control circuit 73
Output to.

The parameter setting unit 74 stores and sets parameters according to the load and the operating specifications in predetermined locations in each axis inverter control circuit 73. The content of the parameter can be appropriately changed by the external host controller 8 connected via the communication interface 75, or can be directly changed by the operator or switch of the parameter setting unit 74. There is.

Each axis inverter control circuit 73 has parameters set by the parameter setting section 74 and speed command signals T1a, T1b and T1c from the position control section 71.
Is output to the power converters 3a, 3b and 3c to control the rotation speeds of the induction motors 1a, 1b and 1c, respectively. The control signal of each axis inverter control circuit 73 is supplied to the voltage control circuit 3 via the serial communication interface 76 and the serial communication interfaces 34a, 34b and 34c in the power converters 3a, 3b and 3c.
2a, 32b and 32c, and an inverter circuit 33
a, 33b and 33c, respectively. That is, each axis inverter control circuit 73 outputs the PWM signal to the inverter circuits 33a, 33b and 33c via the interfaces 34a, 34b and 34c, drives and controls the respective power transistors, and the induction motors 1a, 1c.
A drive current of a predetermined frequency is supplied to each of the phases b and 1c (U phase, V phase, W phase) to control the rotation speed of the induction motors 1a, 1b and 1c.

The serial communication interface 76 is connected to the host controller 8 via the communication interface 75, and various data from the host controller 8 are transferred to the serial communication interfaces 34a, 34b in the power converters 3a, 3b, 3c. And 34c. Between the serial communication interface 76 and the serial communication interface 34a, between the communication interface 34a and the serial communication interface 34b, and the communication interface 3
4b and the serial communication interface 34c are connected to each other by bidirectional serial communication lines to form a multipoint connection, and various data from the host controller 8 and the power converters 3a, 3b and 3c are generated. Data is exchanged between the two parties.

The power converters 3a, 3b and 3c are converter circuits 31a, 31b and 31c, voltage control circuits 32a, 32b and 32c, and an inverter circuit 33, respectively.
a, 33b and 33c, and serial communication interfaces 34a, 34b and 34c. The converter circuits 31a, 31b and 31c convert the three-phase AC voltage (R phase, S phase, T phase) from the external power source 5 into a DC voltage, and the DC voltage is converted into the voltage control circuits 32a, 32b and 3c.
Inverter circuits 33a, 33b and 33c via 2c
Supply to.

Voltage control circuits 32a, 32b and 32c
Extracts a part of the DC voltage from the converter circuits 31a, 31b and 31c as the power supply voltage of the power converters 3a, 3b and 3c, and the DC voltage becomes a predetermined value or more due to the regenerative energy during braking. Monitor whether the voltage from the power supply 5 drops and drops below a specified value.
When the voltage falls below a predetermined value, the voltage drop signal is sent to the host controller 8 via the serial communication interfaces 76, 34a, 34b and 34c and the communication interface 75.
Send to.

Inverter circuits 33a, 33b and 33c
Is a three-phase AC voltage (U-phase, V-phase) with a DC voltage supplied via the voltage control circuits 32a, 32b, and 32c within a predetermined range (about 360 Hz) based on a control signal from the inverter control circuit 34. , W phase) and applied to the induction motors 1a, 1b and 1c, respectively.

At this time, the current feedback signals T2a and T2b detected by the current detection isolator CT.
And T2c are serial communication interfaces 34a, 34
It is fed back to each axis inverter control circuit 73 via b and 34c. Each axis inverter control circuit 73
This current feedback signal T2a, T2b and T2c
Based on the above, it is monitored whether the overcurrent is more than the rated output current. In addition, each of the axis inverter control circuits 73, when the voltage drop signals are output from the voltage control circuits 32a, 32b and 32c, the corresponding power converters 3a, 3b.
Alternatively, it operates as a protection circuit for stopping the operation of 3c. Then, when such an abnormality occurs, each axis inverter control circuit 73 transmits the state to the host controller 8 via the serial communication interface 76 and the communication interface 75.

In addition, each power converter 3a, 3b and 3c
Serial communication interfaces 34a, 34b and 34
c is an inverter rating code indicating the ratings of the inverter circuits 33a, 33b and 33c, or the induction motors 1a, 1b.
And a data memory storing various data such as a motor rating code indicating the rating of 1c. The host controller 8 reads out the data in the data memory via the communication interface 75 and the serial communication interface 76 as necessary, and sets parameters according to the ratings of the inverter circuit and the induction motor for each axis inverter control circuit. Set to 73. Therefore, even if the induction motor and the power converter are appropriately replaced, the position control means 7 can properly control the replaced induction motor and the power converter.

Next, the operation of this embodiment will be described. First,
In the motor control system as shown in FIG. 1, the host controller 8 includes the power converters 3a, 3b and 3 respectively.
c, and the inverter rating code indicating the rating of the induction motors 1a, 1b and 1c and the motor rating code are read from the data memory in the serial communication interfaces 34a, 34b and 34c via the communication interface 75 and the serial communication interface 76. . Then, the host controller 8 sets the parameters based on the read data to the communication interface 75 and the parameter setting unit 74.
It is set in each axis inverter control circuit 73 via. Thereby, each axis inverter control circuit 73 specifies the ratings of the power converters 3a, 3b and 3c, and the induction motors 1a, 1b and 1c, and functions according to the ratings.

Next, the host controller 8 is the induction motor 1
Position command signal P1 indicating the target positions of a, 1b and 1c
It outputs a, P1b, and P1c to the position control unit 71 via the communication interface 75. The position control unit 71 controls the speed command signals T1a, T1b and T1c based on the position deviation between the position command signals P1a, P1b and P1c and the current position signals Pa, Pb and Pc from the position sensor conversion circuit 72.
Is output to each axis inverter control circuit 73. Each axis inverter control circuit 73 controls the speed command signals T1a, T1b and T1.
1c and control signals according to preset parameters via the serial communication interfaces 76, 34a, 34b and 34c. Inverter circuits 33a, 33b and 3
3c to control the rotation speeds of the induction motors 1a, 1b and 1c, respectively. Induction motors 1a, 1b and 1
The outputs Pa, Pb and Pc of the rotational position sensors 2a, 2b and 2c coupled to c are fed back to the position control means 7, respectively. The motor control system repeats the above operation to control the rotation of the induction motors 1a, 1b and 1c.

In the course of this control, if an abnormality such as a power supply voltage drop, overcurrent, overvoltage, or overheat occurs, data indicating these control states is given to each power converter 3.
a, 3b and 3c serial communication interface 34
a, 34b and 34c, serial communication interface 7
6 and the communication interface 75 to the upper controller 8. Upon receiving these data, the host controller 8 performs processing according to the data.

Next, the structure of the rotational position sensors 2a, 2b and 2c used in this embodiment will be described. FIG. 2 is a diagram showing an absolute type position sensor composed of an inductive type phase shift type position sensor which is an example of the rotational position sensor 2a used in the present embodiment. The details of this position sensor are known in JP-A-57-70406 or JP-A-58-106691, and therefore will be briefly described here.

The rotational position sensor 2a has a stator 21 in which a plurality of poles A to D are provided at predetermined intervals (90 degrees as an example) in the circumferential direction, and a space inside the stator 21 surrounded by the poles A to D. And a rotor 22 inserted in the.
The rotor 22 is coupled to the rotary shaft of the induction motor 1a, and has a shape and a material that changes the reluctance of the poles A to D according to the angle of the rotary shaft, and is, for example, an eccentric cylinder. The primary coils 1A to 1D and the secondary coils 2A to 2D are wound around the respective poles A to D of the stator 21. A first pair of two poles A and C and a second pair of poles B and D, which are opposed to each other in the radial direction, are coiled so as to operate differentially and are differential. It is configured to cause a reluctance change.

The primary coils 1A and 1C wound on the first pole pair A and C are excited by the sinusoidal signal sinωt and the primary coil 1 wound on the second pole pair B and D.
B and 1C are excited by the cosine signal cosωt. As a result, their combined output signal Y is obtained from the secondary coils 2A to 2D. This combined output signal Y is a primary AC signal (excitation signal of the primary coil) sinω that serves as a reference signal.
A signal Y = s obtained by phase-shifting t or cosωt by an electrical phase angle θ corresponding to the rotation angle θ of the rotor 22.
in (ωt−θ).

Therefore, when the induction type phase shift type position detecting means as described above is used, the primary AC signal sin
It is necessary to include a reference signal generator that generates ωt or cosωt and a phase difference detector that measures the electrical phase shift θ of the combined output signal Y and calculates rotor position data. The reference signal generator and the phase difference detector are provided in the position sensor conversion circuit 72.

FIG. 3 is a diagram showing an example of the position sensor conversion circuit 72. In FIG. 3, the position sensor conversion circuit 72 includes a reference signal generator that generates reference AC signals sinωt and cosωt, and a phase difference (a phase shift amount) between the mutual induction voltage of the secondary coils 2A to 2D and the reference AC signal sinωt. )
And a phase difference detection unit for detecting Dθ.

The reference signal generator is composed of a clock oscillator 52, a synchronous counter 53, ROMs 54a and 54b, D / A converters 55a and 55b and amplifiers 56a and 56b, and a phase difference detector is an amplifier 57, a zero cross circuit 58 and a latch circuit. It consists of 59. The clock oscillator 52 generates a high-speed and accurate clock signal, and other circuits operate based on this clock signal. The synchronous counter 53 counts the clock signal of the clock oscillator 52 and outputs the count value as an address signal to the ROM 54a and the latch circuit 59 of the phase difference detector.

The ROMs 54a and 54b store amplitude data corresponding to the reference AC signal, and the synchronous counter 53
Amplitude data of the reference AC signal is generated according to the address signal (count value) from the. ROM 54a is sinωt
, And the ROM 54b stores the amplitude data of cos ωt. Therefore, the ROMs 54a and 54b receive the same address signal from the synchronization counter 53 to generate two types of reference AC signals sinωt and cos.
Output ωt. Even if the ROM of the same amplitude data is read by the address signals having different phases, the same 2
A type of reference AC signal can be obtained.

The D / A converters 55a and 55b are the ROM 5
The digital amplitude data from 4a and 54b is converted into an analog signal and output to the amplifiers 56a and 56b. The amplifiers 56a and 56b amplify the analog signal from the D / A converter and use it to amplify the reference AC signals sinωt and cos.
ωt is applied to each of the primary coils 1A, 1C and 1B to 1D. Assuming that the frequency division number of the synchronous counter 53 is M, the M count is the maximum phase angle 2 of the reference AC signal.
This corresponds to π radian (360 degrees). That is, one count value of the synchronous counter 53 indicates a phase angle of 2π / M radian.

The amplifier 57 amplifies the combined value of the secondary voltage induced in the secondary coils 2A to 2D, and the zero cross circuit 5
Output to 8. The zero cross circuit 58 is the rotational position sensor 2
The zero cross point from the negative voltage to the positive voltage is detected based on the mutual induction voltage (secondary voltage) induced in the secondary coils 2A to 2D of a, and the detection signal is output to the latch circuit 59.

The latch circuit 59 latches the count value of the synchronous counter started by the rising clock signal of the reference AC signal at the output point (zero cross point) of the detection signal of the zero cross circuit 58. Therefore, the value latched by the latch circuit 59 is exactly the phase difference (phase shift amount) Dθ between the reference AC signal and the mutual induction voltage (combined secondary output).

That is, the combined output signal Y = sin (ωt-θ) of the secondary coils 2A to 2D is the zero cross circuit 58.
Given to. The zero-cross circuit 58 outputs the pulse L in synchronization with the timing when the electric phase angle of the combined output signal Y is zero. The pulse L is used as a latch pulse for the latch circuit 59. Therefore, the latch circuit 59 latches the count value of the synchronous counter 53 in response to the rising of the pulse L. The period in which the count value of the synchronous counter 53 makes one cycle is synchronized with one cycle of the sine wave signal sinωt. Then, the latch circuit 59 latches the count value corresponding to the phase difference θ between the reference AC signal sinωt and the combined output signal Y = sin (ωt−θ). Therefore, the latched value is output as digital position data Dθ. The latch pulse L can also be used as a timing pulse as appropriate.

Since the synthetic output signal Y of the phase shift type position detecting means as shown in FIG. 3 outputs the absolute rotational position as a phase difference signal, it has a characteristic that it is hardly influenced by noise. The rotation position detecting means in FIG. 3 detects one rotation range absolutely, but by combining a plurality of such absolute sensors, it is possible to detect the absolute position over multiple rotations.

FIG. 4 is a view showing the external appearance of the motor control system of FIG. 1 stored in a rack. Power supply unit 5
0 accommodates the external power source 5 and the electromagnetic contactor 51 of FIG. 1, and includes a position control unit 7, power conversion units 3a, 3
This is a unit for supplying a three-phase AC voltage (R phase, S phase, T phase) to b and 3c. The position control unit 70 houses the position control means 7 of FIG.
a, 30b and 30c are the power conversion means 3a, 3 of FIG.
It contains b and 3c respectively.

Each unit is stored in the rack 81. Power conversion units 30a, 30b and 30
Since c accommodates the converter circuits 31a, 31b and 31c and the inverter circuits 33a, 33b and 33c, it generates a considerable amount of heat as compared with the power supply unit 50 and the position control unit 70. Therefore, in this embodiment, the power conversion units 30a, 30b and 30c are installed in the rack 81.
They are arranged adjacent to each other inside, and a heat absorbing plate 82 is attached to a rear side surface which is a heat generating portion thereof.

A heat pipe 83 is connected to the heat absorption plate 82, and the power conversion unit 30a,
The heat generated in 30b and 30c is radiated to a heat dissipation portion provided outside the rack 81. That is, in this embodiment, the power conversion unit 3 that generates a large amount of heat
0a, 30b and 30c are arranged adjacent to each other, and the heat generated from each unit is radiated to the outside by the common heat dissipation device (the heat absorbing plate 82 and the heat pipe 83). The heat dissipation plate 82 may have a fin structure so that the heat is directly dissipated into the outside air.

In the prior art of FIG. 5, since the logic circuit was built in the inverter device, the inverter device and the motor could not be arranged close to each other, but in this embodiment, the power conversion of the inverter device is performed. Since the section and the logic section are separately arranged, in the embodiment of FIG. 1, the power conversion means 3a, 3b and 3c are incorporated in the corresponding induction motors 1a, 1b and 1c, and both may be integrated. Good.

Although the induction motor has been described as an example, it may be a synchronous type motor or another type of motor such as a DC type motor, not limited to an AC type motor. Further, the rotational position sensor is not limited to the inductive type phase shift type detecting means, but an optical absolute encoder, an incremental encoder, or another type of sensor may be used to output the absolute position data.

[0048]

According to the inverter device of the present invention, the power conversion means for controlling a high current and a high voltage is arranged in the vicinity of a motor or the like, while the inverter control means constituted by a logic circuit or the like is somewhat similar to the motor or the like. Since it can be installed with a distance of, the logic circuit in the inverter control means is not affected by the noise generated in the power conversion means,
This has the effect of reducing malfunctions of the logic section.

According to the motor control system of the present invention, even when the ratings of the motor and the power conversion means are changed,
There is an effect that it is possible to promptly respond to a change in the motor, etc., only by changing and setting the parameters according to the ratings of the changed motor and the power conversion means.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a motor control system of the present invention.

FIG. 2 is a diagram showing a detailed configuration of an inductive type phase shift type position sensor which is an example of a rotational position sensor used in the embodiment of FIG.

FIG. 3 is a diagram showing an example of a position sensor conversion circuit used in the embodiment of FIG.

FIG. 4 is a diagram showing an appearance when the motor control system of FIG. 1 is stored in a rack.

FIG. 5 is a diagram showing a schematic configuration of a motor control system when positioning control of an induction motor using a conventional inverter device.

[Explanation of symbols]

1a, 1b, 1c ... Induction motor, 2a, 2b, 2c ... Rotational position sensor, 3a, 3b, 3c ... Power conversion means, 3
1a, 31b, 31c ... Converter circuit, 32a, 32
b, 32c ... Voltage control circuit, 33a, 33b, 33c ...
Inverter circuit, 34a, 34b, 34c ... Serial communication interface, 5 ... External power supply, 51 ... Electromagnetic contactor,
7 ... Position control means, 71 ... Position control section, 72 ... Position sensor conversion means, 73 ... Each axis inverter control circuit, 74 ... Parameter setting section, 75 ... Communication interface, 76 ... Serial communication interface, 8 ... Upper controller

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location H02P 5/41 302 Q 9178-5H 7/74 G 9063-5H H04L 12/00 H04Q 9/00 7170 -5K

Claims (7)

[Claims] 1. A power conversion means for converting a DC drive current into an AC drive current of a predetermined frequency according to a control signal, and the control signal to the power conversion means according to a speed command signal and a parameter set inside. In an inverter device including an inverter control unit for outputting, the power conversion unit and the inverter control unit are separated and configured as separate units, and data transmission between them is performed by a bidirectional serial communication line. An inverter device characterized by the above. 2. A parameter setting that is connected to a host controller via a second communication line and that changes the parameter setting according to an instruction from the host controller via the second communication line even while the inverter device is operating. 2. The inverter device according to claim 1, wherein the means is provided in the same unit as the inverter control means. 3. A plurality of power conversion means provided in each of the plurality of motors, for converting a DC drive current into an AC drive current of a predetermined frequency according to a control signal input from the outside and supplying the AC drive current to the motor. An inverter control means for outputting the control signal to each of the plurality of power conversion means via a bidirectional serial communication line according to a speed command signal input from the outside and a parameter set inside, It is connected to the host controller via the communication line of 2.
An inverter device comprising: parameter setting means for changing the setting of the parameter according to an instruction from the host controller via the second communication line even while the inverter control means is in operation. 4. A plurality of motors, each of which is provided in each of the plurality of motors, converts a DC drive current into an AC drive current of a predetermined frequency according to a control signal input from the outside, and supplies the AC drive current to the motor. A plurality of power conversion means, a position sensor provided in each of the plurality of motors for detecting a signal indicating the current position of the motor, a speed command signal input from the outside and a parameter set in the inside. An inverter control means for outputting the control signal to each of the plurality of power conversion means via a bidirectional serial communication line, a parameter setting means for changing the setting of the parameter, and a target position of the motor. A position command signal and a signal indicating the current position of the motor are input and the speed command signal based on these signals is controlled by the inverter. Position control means for outputting to a stage, a host controller for outputting the position command signal and the parameter for controlling the rotation of the motor, and a position command connected to the host controller via a second communication line. A motor control system comprising: a communication unit that outputs a signal to the position control unit and the parameter to the parameter setting unit. 5. The position sensor for detecting the current position of the motor is an absolute type position sensor for detecting the position of the motor as an absolute position, and the winding part and the relative position with respect to the winding part. And a member that changes the magnetic resistance in the winding portion according to the relative position thereof, and the winding portion is excited by a plurality of phase-shifted primary AC signals, and the absolute position of the motor is set. The motor control system according to claim 4, wherein the motor control system comprises a phase shift type position sensor that generates an output AC signal having a corresponding electrical phase shift. 6. The plurality of power converting means are arranged adjacent to each other in a rack, and a heat radiating means is commonly provided for each heat generating section of the power converting means, and heat from the heat generating section is provided via the heat radiating means. The motor control system according to claim 4, wherein the heat is radiated to the outside. 7. The motor control system according to claim 4, wherein the power conversion means is built in the motor, and both are integrated.