EP0333054A1
Expired / Lapsed
EP
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Control system for controlling revolution speed of electric motor
Assignee: Meidensha Corp
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Filing: 1989-03-10
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Granted: —
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Expires: 2009-03-10
Abstract
Abstract A motor speed control system controls torque current and exitation current for vector controlling an induction motor. The control system takes a core loss as one of parameter for deriving torque current and excitation current for precise control of the induction mode.
Inventors
- 👤 Takayuki Mizuno
- 👤 Tadashi Ichioka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 07:43
CPC Classifications
H; H02; H02P; H02P5/00; H02P21/00; H02P21/14; H02P21/16; H02P2207/00; H02P2207/01
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
160 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -{(Rm² + ω²ML₂)/(Rm² + ω²M²)} x I T * - {ωMRm/(Rm² + ω²M²)} x I o * Il q = {ω²M²/(Rm² +ω²M²)} x I o * + {(Rmω(M - L₂)/(Rm² + ω²M²)} x I T * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
Claim 2
Dependent Claim
160 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -{(Rm² + ω²ML₂)/(Rm² + ω²M²)} x I T * - {ωMRm/(Rm² + ω²M²)} x I o * Il q = {ω²M²/(Rm² +ω²M²)} x I o * + {(Rmω(M - L₂)/(Rm² + ω²M²)} x I T * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
Claim 3
Dependent Claim
148 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -(L₂/M) x I T * - {ωMRm/(Rm² + ω²M²) x I o * Il q = - {ω²M²/(Rm² + ω²M²)} x I o * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
Claim 4
Dependent Claim
148 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -(L₂/M) x I T * - {ωMRm/(Rm² + ω²M²) x I o * Il q = - {ω²M²/(Rm² + ω²M²)} x I o * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
Claim 5
Dependent Claim
143 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -(L₂/M) x I T * - {ωMRm/(Rm² + ω²M²) x I o * Il q = I o * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
Claim 6
Dependent Claim
143 words
A motor speed control system for an induction motor, comprising: said induction motor; a motor driving circuit for applying power to drive the motor, a sensor means associated with said indication motor, for monitoring a revolution speed thereof and producing a motor speed indicative signal; and a vector controlling means for controlling a flux-axis primary current Il q , a torque-axis primary current Il d and slip frequency ωs to establish the following condition: Il d = -(L₂/M) x I T * - {ωMRm/(Rm² + ω²M²) x I o * Il q = I o * ωs = (R₂/M) x (I T */I o *) where I T * is torque current command; I o * is exitation current command; M is a relative inductance; L₂ is a secondary inductance; R₂ is a secondary resistance; and ω is a power source angular frequency.
References Cited (Backward Citations)
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