PHASE DIFFERENCE DETECTION DEVICE, PHASE DIFFERENCE DETECTION PROGRAM, AND PLASMA PROCESSING SYSTEM USING PHASE DIFFERENCE DETECTION DEVICE

Title:

PHASE DIFFERENCE DETECTION DEVICE, PHASE DIFFERENCE DETECTION PROGRAM, AND PLASMA PROCESSING SYSTEM USING PHASE DIFFERENCE DETECTION DEVICE

Document Type and Number:

Japanese Patent JP2013250231

Kind Code:

A

Abstract:

To quickly and highly accurately detect a phase difference between two AC signals.

A phase difference operation part calculates a phase difference φ_r(=φ₂-φ₁) of two detected voltages v₁(phase angle φ₁), v₂(phase angle φ₂). After operating v_2s=v₂×v_s, v_2c=v₂×v_c, v_1s=v₁×v_s, v_1c=v₁×v_c by using a sine wave v_s and a cosine wave v_c having the same frequency as a basic frequency of the generated voltages v₁,v₂, DC components I₂=(A₂/2)*sin(φ₂), R₂=(A₂/2)*cos(φ₂), I₁=(A₁/2)*sin(φ₁), R₁=(A₁/2)*cos(φ₁) are extracted by a low pass filter. A complex multiplier operates R₃=R₁×R₂+I₁×I₂, calculates R₃=(A₁*A₂/4)*cos(φ_r), operates I₃=R₂×I₁-R₁×I₂, and calculates I₃=(A₁*A₂/4)*sin(φ_r). An inverse tangent computing unit operates φ_r=tan^-1(I₃/R₃) and calculates a phase difference φ_r.

Inventors:

KITANO TOYOKAZU
KASAI YOSHINOBU
YOSHIZAKO YUJI

Application Number:

JP2012127048A

Publication Date:

December 12, 2013

Filing Date:

June 04, 2012

Export Citation:

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Assignee:

DAIHEN CORP

International Classes:

G01R25/00; H01L21/3065; H05H1/46

Domestic Patent References:

JPH04370772A	1992-12-24
JPH10326698A	1998-12-08
JP2002329599A	2002-11-15
JP2008130398A	2008-06-05
JPH09161994A	1997-06-20

Attorney, Agent or Firm:

Minoru Yoshida
Tatsuya Tanaka
Tsukasa Senba
Yasumitsu Suzuki
Nao Usui

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