Patent EP0148269B1 successfully refreshed from Google Patents.
EP0148269B1
Expired / Lapsed
EP
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Servo driving unit
Assignee: Fanuc Corp
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Filing: 1984-03-02
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Granted: 1992-07-29
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Expires: 2004-03-02
Abstract
Abstract A servo driving unit enables the use of hardware in common within various control modes by changing the program controllng a processor in accordance with the control mode. A processor (108a) in an operational control unit (108) selects various control programs from a program memory (108b) in answer to commands from an interface circuit (108d), and prepares an inverter driving command from an armature current detection value input from an AD converter (108f) and a rotational angle detection value input from a counter (108g). The inverter driving command is output to a timer circuit (114) through an input/output port (108e), and controls an inverter (115) so that it varies a current driving a servo motor (101).
Inventors
- 👤 Mitsuo Kurakake
- 👤 Keiji Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 08:56
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B19/237; H; H02; H02P; H02P25/00; H02P25/02; H02P25/022; H02P25/03; G05B2219/00; G05B2219/30; G05B2219/34; G05B2219/34215; G05B2219/34426; G05B2219/35; G05B2219/35252; G05B2219/36; G05B2219/36511; G05B2219/37; G05B2219/37154; G05B2219/41; G05B2219/41248; G05B2219/42; G05B2219/42104
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
283 words
A servomotor drive unit including a voltage supply circuit (115) for supplying an armature voltage to a servomotor (101), a current detector (112) for detecting the armature current in the servomotor (101), a rotational angle detector (102) for detecting the rotational angle of the servomotor (101), and an arithmetic controller (108) having a memory (108b) for storing a motor control program, an interface circuit (108d) for receiving external commands, and a processor (108a) connected to the rotational angle detector (102) and responsive to commands supplied from the said interface circuit (108d) for executing the motor control program to control the current supplied from said voltage supply circuit (115), characterised in that the current detector (112) is likewise connected to the processor (108a) and the arrangement is such that the servomotor drive unit can follow any of a positional command (PCMD), a speed command (VCMD), and a current command (ICMD) received through the said interface circuit (108d), by virtue of a motor control program which is stored in the memory (108b) for carrying out by the processor (108a), the program defining a predetermined series of processor steps which is: such as to enable the servomotor drive unit to follow said positional command (PCMD); such as to enable the servomotor drive unit to follow said speed command (VCMD) if an initial number of the predetermined series of processor steps is omitted; and such as to enable the servomotor drive unit to follow said current command (ICMD) if said initial number, together with more, of the predetermined series of processor steps are omitted; whereby a single motor control program can be modified to provide all of positional command control, speed command control and current command control.
Claim 2
Dependent Claim
417 words
A servomotor drive unit according to claim 1, wherein said predetermined series of processor steps defined by the motor control program is as follows: (1) a first processor step of receiving a positional command PCMD from a numerical control apparatus or the like through the interface circuit (108d); (2) a second processor step of calculating an interval of movement PAD in dependence upon the rotational angle detector (102); (3) a third processor step of calculating a command speed Vc from the expression Vc = Kp (PCMD-PAD) where Kp is a constant positional loop gain; (4) a fourth processor step of calculating an actual speed Va by dividing an interval of movement by a corresponding sampling period T; (5) a fifth processor step of determining an armature current amplitude command Ir from the expression (6) a sixth processor step of generating digital waves from a conversion table in dependence upon the rotational angle ϑ detected in dependence upon the rotational angle detector (102); (7) a seventh processor step of deriving three-phase armature current commands I R , I S , I T employing the current amplitude command I r and said digital sine waves; (8) an eighth processor step of calculating drive signals for the voltage supply circuit (115) in dependence upon the differences between said three-phase armature current commands I R , I S , I T and the actual three-phase armature currents Iav, Iaw, Iau detected by said current detector (112); (9) a ninth processor step of compensating the current loop control by subtracting from said drive signals a speed compensation output VCO obtained by multiplying said actual speed Va by a prescribed coefficient, thereby to avoid a current loop gain reduction which would otherwise be caused by a counterelectromotive force due to the actual speed Va; (10) a tenth processor step of generating pulse-width-modulation commands for the voltage supply circuit (115) from the compensated drive signals; and (11) an eleventh processor step of delivering the pulse-width-modulation commands to the voltage supply circuit (115), and wherein all the eleven processor steps will be executed to enable the servomotor drive unit to follow said positional command (PCMD) received through the said interface circuit (108d); the first three processor steps will be omitted to enable the servomotor drive unit to follow a speed command received through the said interface circuit (108d); and the first five processor steps will be omitted to enable the servomotor drive unit to follow a current command received through the said interface circuit (108d).
References Cited (Backward Citations)
No citation records indexed.
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