JPH05252688A - Intelligent motor - Google Patents

Abstract

PURPOSE:To realize an intelligent motor suitable for autonomous distribution of system by incorporating a servo drive unit having function for controlling the driving of a servo motor in the housing of the servo motor. CONSTITUTION:An AC servo motor is employed as a servo motor 1 and a permanent magnet 22 generating field flux is fixed, as a rotor, to the shaft 21 of the motor. In particular, a servo drive unit 15 having function for controlling the driving of the servo motor 1 is built in the housing of the servo motor 15. The servo drive unit 15 is connected through a winding/drive circuit connecting cable 31 with three-phase armature windings 24. Consequently, a power supply unit 4 and a controller 5 can be connected directly with the servo motor 1. According to the constitution, wiring between the servo motor 1 and external circuits can be reduced remarkably and autonomous distributed control of the servo motor 1 can be realized in a system constituted of a plurality of servo motors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new intelligent motor suitable for power sources such as NC machine tools and robots.

[0002]

2. Description of the Related Art In NC machine tools and robots, AC servomotors and DC servomotors are used as power sources.

FIG. 4 shows a block diagram of a conventional AC servo motor system. An encoder 2 for performing feedback control is connected to the servo motor 1. A servo drive unit 3 is connected to the servo motor 1 and the encoder 2. The servo drive unit 3 is connected to a power supply unit 4 that supplies power and a controller 5 that controls the servo drive unit 3. A plurality of servo drive units 3, an encoder 2 and a servo motor 1 are connected to the power supply unit 4 and the controller 5.

FIG. 5 is a block diagram of the servo drive unit 3 shown in FIG. In FIG. 5, a motor drive circuit (inverter circuit) 6 is connected to the servomotor 1.
A power supply controller 7 and a current controller 8 for performing PWM control are connected to the motor drive circuit 6. The power supply unit 4 and the protection circuit 11 are connected to the power supply control unit 7. A positioning control unit 9, a speed control unit 10 and a sequence circuit 12 are connected to the current control unit 8. The positioning controller 9 includes an encoder 2, a controller 5, and a speed controller 10.
And the sequence circuit 12 is connected. The controller 5 and the sequence circuit 12 are also connected to the speed control unit 10. A sequence circuit 12 is connected to the protection circuit 11. The controller 5 is provided in the sequence circuit 12.
Is also connected.

FIG. 6 is a block diagram when an AC servomotor is used as the servomotor 1 of FIG. Motor shaft 2
1 is a permanent magnet 22 for generating a field magnetic flux as a rotor.
Is attached. A three-phase armature winding 24 is wound around an iron core 23 as a stator. When a current is applied to the three-phase armature winding 24 in the magnetic field of the permanent magnet 22, the shaft 21 to which the permanent magnet 22 as the rotor is attached is rotated by Fleming's left-hand rule. Here, when a sinusoidal current PWM-controlled according to the rotor position is passed through each winding of the three-phase armature winding 24, torque proportional to the current flowing through each winding is generated, and the rotor shaft 21 Will rotate while being controlled by the electric current. An encoder 2 for feedback control of speed and position is connected to the end of the shaft 21. Servo drive unit 3 is A
C 3-phase armature winding 24 of servomotor 1 and encoder 2
Are connected to each via separate cables. In FIG. 6, the encoder cable is indicated by reference numeral 33. The servo motor unit thus configured is used as a uniaxial power source.

By the way, NC machine tools, robots, etc. require at least 2-3 axes, and many have 6 or more axes.

[0007]

However, according to the conventional configuration, there is a problem that the above-mentioned servo motor unit is required for each axis, and the whole system becomes large and the wiring radiates. .

Further, the trend in the field of control systems is toward autonomous decentralization, and there is a trend toward intelligent units such as sensors and drive sources. This is NC
It is also essential in the fields of machine tools and robots.

The present invention has been made in view of the above problems, and an object thereof is to provide an intelligent motor suitable for autonomous decentralization of a system.

[0010]

An intelligent motor according to the present invention is characterized in that a servo drive unit having a function of driving and controlling the servo motor is incorporated in a housing of the servo motor.

[0011]

Since each servo motor has a built-in servo drive unit having a function of controlling the drive of the servo motor, the power supply unit and the controller can be directly connected to the servo motor.

As a result, the wiring for connecting the servo motor and the outside can be greatly reduced, and the autonomous distributed control of the servo motor can be performed when the system is composed of a plurality of servo motors.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram of an embodiment of the present invention, in which the same parts as those in FIG. 6 are designated by the same reference numerals. 1 is different from FIG. 6 in that a servo drive unit 15 having a function of driving and controlling the servo motor 1 is incorporated in the housing of the servo motor 1. The servo drive unit 15 includes a three-phase armature winding 24 and a winding
It is connected via a drive circuit connection cable 31.

FIG. 2 is a circuit diagram showing the electrical connection relationship of FIG. 1, and the portions common to FIG. 5 are given the same numbers. 1 is different from FIG. 5 in that a CPU 32 is provided instead of the sequence circuit 12, and a communication circuit 13 for performing communication between the CPU 32 and the controller 5 is provided. Further, the CPU 32 is provided with a boot ROM 14 in which a communication program is written.

The operation of such a circuit configuration is as follows. The power supply controller 7 controls the power supplied from the external power supply unit 4 to a desired voltage and outputs it to the motor drive circuit 6. The motor drive circuit 6 generates an AC voltage having a required frequency and supplies a three-phase sine wave current to the armature winding of the servo motor 1. The current control unit 8 sets the motor drive circuit 6 to PW.
M control. The positioning control unit 9 performs position feedback control based on the angle signal output from the encoder 2. The speed control unit 10 obtains a speed deviation from the speed command value from the controller 5 and the speed signal output from the encoder 2 to perform torque control. The CPU 32 controls and calculates each control unit. The communication circuit 13 is an external controller 5 according to a program stored in the ROM 14.
And the CPU 32 communicate with each other.

Here, the servo drive unit 15 is
By integrating the intelligent power IC into a single chip, small size and low price can be realized. By incorporating the servo drive unit 15 having the function of controlling the drive of the servo motor 1 in the housing of the servo motor 1 as described above, the cable connecting the servo motor 1 and the external device has one signal for each servo motor 1. It suffices to prepare one set consisting of a line and a few power lines, and in the case of multi-axis control, only the servo motors 1 for the number of axes need to be added as shown in FIG.

Although the AC servomotor has been described in the above embodiment, the same intelligent operation can be realized by using a DC servomotor, a stepping motor or the like.
Further, although the encoder is used for the angle feedback in the above embodiment, a resolver or the like may be used as long as it is a sensor for detecting the angle.

The servo drive unit 15 may use a substrate circuit instead of the one-chip intelligent power IC.

[0019]

According to the present invention described in detail above, the following effects can be obtained. The system can be simplified by eliminating the external servo drive unit. Since the connection with the encoder is made inside the motor, the connection with the outside consists of one signal line and a few power lines.
Only a set of cables is needed, and wiring for system configuration can be simplified. Since the servo motor has a CPU and a communication circuit, it can be made compatible with various controllers. Since the CPU is built into the servo motor to make it intelligent, the load on the controller can be reduced. Since the CPU is incorporated into the servomotor to make it intelligent, the system can be autonomously decentralized.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an electrical connection relationship of FIG.

FIG. 3 is a configuration diagram of a multi-axis servomotor system according to the present invention.

FIG. 4 is a configuration diagram of a conventional multi-axis servomotor system.

5 is a block diagram of the servo drive unit shown in FIG. 4. FIG.

6 is a configuration diagram when an AC servomotor is used as the servomotor 1 in FIG.

[Explanation of symbols]

 1 Servo Motor 2 Encoder 4 Power Supply Unit 5 Controller 13 Communication Circuit 14 ROM 15 Servo Drive Unit 32 CPU

Claims (1)

[Claims] 1. An intelligent motor characterized in that a servo drive unit having a function of driving and controlling the servo motor is incorporated in a housing of the servo motor.