TECO L510S Series - Page 123

4-78
11 Performance control functions
11- 00 Prevention of Reverse operation
Range
【0】:Reverse command is valid
【1】:Reverse command is invalid
11- 01 Carrier Frequency
Range 【1~16】KHz
11- 02 Carrier mode selection
Range
【0】:Carrier mode0 3-phase PWM modulation
【1】:Carrier mode1 2-phase PWM modulation
【2】:Carrier mode2 random PWM modulation
The function can be used for audible noise reduction from a motor. It can be used in cases
where the 100% torque from motor is not critical but it is necessary to reduce the audible
noise.

 Mode 0: 3‐phasePWMModulation.ThreeOutputtransistorsareONatthesametime
(FullDuty).Carrier frequency is set according to Parameter 11-01
 Mode 1:
2‐phasePWMModulation.TwooutputtransistorsareONatthesametime(2/3Duty).
ThismodeissuitableforvariabletorqueapplicationssuchasFan&pump.Itreducesthe
outputtransistorswitchinglosses.Carrierfrequencywillbeaccordingtoparameter11‐01
withtheexceptionnoted below:
Note:
If11‐01>2KHzand11‐03=0(Autocarrierfrequencychangeisdisa bled)andthelisted
conditionsbelowapplythen2‐phasePWMwillautomaticallychangeto3‐phasePWM
with
Thecarrierfrequency=2/3*(11‐01) 

Conditions:
 DuringAccelerationIfOutputfrequencyis<0.7*Fmax.
 DuringDecelerationwhenoutputfrequencyis<0.6*Fmax
 Fmax=(01‐02)InV/fcontrolmode(00‐00)=0
 Fmax=(02‐06)InSLVmode(00‐00)
=1


Mode 2:Mode2:2‐phasesoftPWMmodulation(RandomPWMModulation).
Thismodulationmethodwilluse3‐phasePWMand2‐phasePWMmodulationina
randomcombination.Carrierfrequencywillbeaccordingtoparameter11‐01

PWMmodeselectionconsiderations:
Modes Name IGBT Duty
Heat
Losses
Torque
Performance
Waveform
Distortion
Motor
Noise
0 3-Phase PWM 100% High High Low Low
1 2-Phase PWM 66.6% Low Low High High
2
2-Phase Random
PWM
66.6% Low Low High Mid