无论是哪一种变频器，都大量使用了晶闸管等非线性电力电子元件，不管采用整流方式，变频器从电网中吸取能量的方式都不是连续的正弦波，而是从脉动的断续方式向电网索取电流，这种脉动电流和电网的沿路阻抗共同形成脉动电压降叠加在电网的电压上，使电压发生畸变，经傅立叶原理分析可知，这种非同期正弦波电流是由于频率相同的基波和频率大于基波频率的谐波组成。
TEKTRONIX SPECTRA 2 - VoIP IMS PSTN PROTOCOL ANALYZER
Tektronix TDS540D 4 Channel 500MHz Digital Oscilloscope
Comes with fresh calibration valid through 8/2011
One-day shipping available
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Tektronix SD-48 30GHz O to E Converter 950~1650nm
Tektronix 1405/03 NTSC TV Sideband Adapter
TEKTRONIX TDS640A Oscilloscope, 500 MHz, 4ch, 2 GS/s
Sony Tektronix 3066 3GHz Real Time Spectrum Analyzer
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Tektronix AWG2041 Arbitrary Waveform Generator+opt:0109
One-day shipping available
Tektronix VM700 - Video Measurement Set
Tektronix AWG2021 Arbitrary Waveform Generator
Tektronix TDS 460A TDS460A scope, NIST-calibrated
additional free NIST recalibration within one year
Tektronix OTS91T2 OC192/STM64 Transmitter Optical Test
@For OTS9010 / OTS9040/ OTS9000 MainFrames@30DWarranty@
