초록 ▼

A sensorless control method for a motor performed by a sensorless controller including a back electromotive force (EMF) observer and a phase locked loop (PLL) controller, includes: estimating a back EMF of the motor using the back EMF observer; calculating an electrical angle error in accordance wit

A sensorless control method for a motor performed by a sensorless controller including a back electromotive force (EMF) observer and a phase locked loop (PLL) controller, includes: estimating a back EMF of the motor using the back EMF observer; calculating an electrical angle error in accordance with iron loss of the motor based on the estimated back EMF; and compensating for the calculated electrical angle error, inputting the compensated electrical angle error into the PLL controller to estimate an actual angle, and controlling the motor based on the estimated actual angle.

대표청구항 ▼

1. A sensorless control method for a motor performed by a sensorless controller including a back electromotive force (EMF) observer and a phase locked loop (PLL) controller, comprising: estimating a back EMF of the motor using the back EMF observer;calculating an electrical angle error in accordance

1. A sensorless control method for a motor performed by a sensorless controller including a back electromotive force (EMF) observer and a phase locked loop (PLL) controller, comprising: estimating a back EMF of the motor using the back EMF observer;calculating an electrical angle error in accordance with iron loss of the motor based on the estimated back EMF;compensating for the calculated electrical angle error;inputting the compensated electrical angle error into the PLL controller to estimate an actual angle; andcontrolling the motor based on the estimated actual angle. 2. The sensorless control method of claim 1, wherein voltages (vγ, vδ) of the motor based on the iron loss are calculated using the following equation: [vγvδ]=[Rs+ωe2⁢Ld⁢LqRi+pLd-ωe⁢Lq+p⁢⁢ωe⁢Ld⁢LqRiωe⁢Lq-p⁢⁢ωc⁢Ld⁢LqRiRs+ωe2⁢Ld⁢LqRi+pLd]⁢ [iγiδ]+⁢⁢[ωe2⁢Ld⁢ψ⁢mRi⁢cos⁢⁢Δθ+Eex⁢sin⁢⁢Δθ-ωe2⁢Lq⁢ψ⁢mRi⁢sin⁢⁢Δθ+Eex⁢cos⁢⁢Δθ]=eγδ′⁢⁢⁢Eex=ωe⁢{(Ld-Lq)⁢id+ψm}-(Ld-Lq)⁢(piq)d, q: accurate d, q-axisωe: electric angular velocity of motorid: d-axis currentiq: q-axis currentidi: d-axis iron loss currentiqi: q-axis iron loss currentidm: d-axis magnetizing currentiqm: q-axis magnetizing currentvd: d-axis voltagevq: q-axis voltageRs: stator phase resistanceRi: Iron loss equivalent resistanceLd: d-axis inductanceLq: q-axis inductanceψm: permanent magnet flux constantPiron: Iron lossPh: hysteresis lossPed: eddy-current losseγ: estimated d-axis extended EMFeδ: estimated q-axis extended EMFe′γ: estimated d-axis extended EMF considering iron losse′δ: estimated q-axis extended EMF considering iron loss. 3. The sensorless control method of claim 1, wherein the back EMF observer estimates voltages (vγ, vδ) of the motor using the following equation: [vγvδ]=[Rs+ωe2⁢Ld⁢LqRi+pLd-ωe⁢Lq+p⁢⁢ωe⁢Ld⁢LqRiωe⁢Lq-p⁢⁢ωc⁢Ld⁢LqRiRs+ωe2⁢Ld⁢LqRi+pLd]⁢ [iγiδ]+[eγ′eδ′]. 4. The sensorless control method of claim 1, wherein the electrical angle error (Δθ+α) is calculated using the following equation: eγ′=ωe2⁢Ld⁢ψ⁢mRi⁢cos⁢⁢Δθ+Eex⁢sin⁢⁢Δθ=(ωe2⁢Lq⁢ψmRi)2+Eex2⁢sin⁡(Δθ+α)eδ′=-ωe2⁢Lq⁢ψ⁢mRi⁢sin⁢⁢Δθ+Eex⁢cos⁢⁢Δθ=(ωe2⁢Lq⁢ψmRi)2+Eex2⁢cos⁡(Δθ+α)⁢Δθ+α=tan-1⁡(eγ′eδ′)⁢⁢α=tan-1(we2⁢Lq⁢ψmRi⁢Eex). 5. The sensorless control method of claim 1, wherein the inputting of the compensated electrical angle error into the PLL controller to estimate the actual angle comprises reducing the electrical angle error based on the iron loss. 6. A sensorless control system controlling a motor including a permanent magnet motor, comprising: a back EMF observer configured to estimate a back EMF of the motor;an angle error calculator configured to calculate an electrical angle error in accordance with iron loss of the motor based on the estimated back EMF;an angle error compensator configured to compensate for the calculated electrical angle error; anda PLL controller configured to: i) receive the compensated electrical angle error, ii) estimate an actual angle, and iii) control the motor based on the estimated actual angle. 7. The sensorless control system of claim 6, wherein voltages (vγ, vδ) of the motor based on the iron loss are calculated by the following equation: [vγvδ]=[Rs+ωe2⁢Ld⁢LqRi+pLd-ωe⁢Lq+p⁢⁢ωe⁢Ld⁢LqRiωe⁢Lq-p⁢⁢ωc⁢Ld⁢LqRiRs+ωe2⁢Ld⁢LqRi+pLd]⁢ [iγiδ]+⁢⁢[ωe2⁢Ld⁢ψ⁢mRi⁢cos⁢⁢Δθ+Eex⁢sin⁢⁢Δθ-ωe2⁢Lq⁢ψ⁢mRi⁢sin⁢⁢Δθ+Eex⁢cos⁢⁢Δθ]=eγδ′⁢⁢⁢Eex=ωe⁢{(Ld-Lq)⁢id+ψm}-(Ld-Lq)⁢(piq)d, q: accurate d, q-axisωe: electric angular velocity of motorid: d-axis currentiq: q-axis currentidi: d-axis iron loss currentiqi: q-axis iron loss currentidm: d-axis magnetizing currentiqm: q-axis magnetizing currentvd: d-axis voltagevq: q-axis voltageRs: stator phase resistanceRi: Iron loss equivalent resistanceLd: d-axis inductanceLq: q-axis inductanceψm: permanent magnet flux constantPiron: Iron lossPh: hysteresis lossPed: eddy-current losseγ: estimated d-axis extended EMFeδ: estimated q-axis extended EMFe′γ: estimated d-axis extended EMF considering iron losse′δ: estimated q-axis extended EMF considering iron loss. 8. The sensorless control system of claim 6, wherein the back EMF observer is further configured to estimate voltages (vγ, vδ) using the following equation: [vγvδ]=[Rs+ωe2⁢Ld⁢LqRi+pLd-ωe⁢Lq+p⁢⁢ωe⁢Ld⁢LqRiωe⁢Lq-p⁢⁢ωc⁢Ld⁢LqRiRs+ωe2⁢Ld⁢LqRi+pLd]⁢ [iγiδ]+[eγ′eδ′]. 9. The sensorless control system of claim 6, wherein the angle error calculator is further configured to calculate the electrical angle error (Δθ+α) using the following equation: eγ′=ωe2⁢Ld⁢ψ⁢mRi⁢cos⁢⁢Δθ+Eex⁢sin⁢⁢Δθ=(ωe2⁢Lq⁢ψmRi)2+Eex2⁢sin⁡(Δθ+α)eδ′=-ωe2⁢Lq⁢ψ⁢mRi⁢sin⁢⁢Δθ+Eex⁢cos⁢⁢Δθ=(ωe2⁢Lq⁢ψmRi)2+Eex2⁢cos⁡(Δθ+α)⁢Δθ+α=tan-1⁡(eγ′eδ′)⁢⁢α=tan-1(ωe2⁢Lq⁢ψmRi⁢Eex). 10. The sensorless control system of claim 6, wherein the PLL controller is further configured to estimate the actual angle by reducing the electrical angle error based on the iron loss.