Figura I ad tres-phase Brushless DC motricium coegi parte schematic
maxime includit praetorium notitia collectio, et secundum foramen, facite correspondentes modulation in modum est pelagus contentus in Bldc est in Motor Imperium est Pelagus in Bldc in Modulation Motors est in Motori et Motor sophisticated, the original common square wave pulse width modulation (PWM) based on 120 degrees, the sine pulse width modulation (变频调速)And space vector pulse width modulation (SVPWM), reduce motor pulse, current waveform distortion is reduced, but the latter two algorithms is more complex, brushless motor, this article will be to introduce three kinds of modulation method one by one to its features, principle et calculata in detail. Various semiconductor lc08000m chip integrated triplici modi mode, idoneam applicationem in Bldc coegi motoribus.
1. 120 degrees square wave pulse width modulation
use value (hallEach electric cycle 6 times change), change the UVW phase current flow, but the same value within current flowing into the same hall, at any time only one phase of the bridge under the bridge and another phase conduction, this control method is simple, but has a maximum torque Angle of 60 degrees, the efficiency is lower, at the same time with the rotation noise.
Brushless DC Motor Pwm initus Frequency Quaestiones
Figura II: De statu contra PWM, tres hall electro vis, correspondentes relatione trium tempus
in diverso ordine ponte PWM Switch potestate in diverso ordine, ut sequi quinquennium modi in ponte pontem PWM ad secundum quod potest facere in his quinque genera, ut non possumus facere in his quinque genera, ut non possumus facere in his quinque genera in modum copia.
LC08000M ut redigendum commutatione torque lacum studuit et adoptavit PWM valorem transitus, hoc processus potest efficaciter reducere gyrationis sonitus.
Brushless DC motor Pwm input frequency problems
Figura III, LC08000M Square-unda CXX & Deg; Pulse width modulation PWM hall in relation to the corresponding figure
2. Sine pulse width modulation (变频调速)
superposition in MOS tube into an equivalent dc voltage can be controlled by PWM switch to sine voltage, due to the neutral point is zero, so also for sinusoidal phase voltage of the motor, so as to make the motor into the phase line current is sinusoidal variation rule, Excluditur torque lacum. Secundum ad aream de aequivalence principium, sine fluctus potest esse equivalent in PWM fluctus. Ut ostensum est in Figura V, per viam, ut assidue adjust in PWM officium ratios sine fluctus intentione effectus.
Brushless DC Motor Pwm input Frequency Quaestiones
Figura IV: De equivalent figure of Sine unda et PWM unda
Sine Pulsus Widavia Modulation): Nescio & Omega; T values in detail, et non solum potest legere from $ aula elementum ad LX & deg; CXX ° CLXXX ° CCCLX ° CCCLX ° Sex Generalis Location Information, sic opus paucis temporibus praeteritis praetorium valores mutare intervallum calculata intra LX gradus angle. In stabilis incipiens casus, non possumus rationem anguli de notitia, ita satus causa, ut utor CXX gradus quadratum undam pulsum latitudine modulatum modus ad sinus, sed adepto a stabulo, vos can in sibilum modum.
Calculate angulum modum, ut ostensum est in Figura VI -1 primum computare inter LX & deg; Opus tempus, divisa a PWM exolvuntur tempus potest esse ratione & LX g; Numerus PWM, unde in LX & Deg; In omni crescere in PWM cum valore angulo incremento, plus valorem correspondentes ad magnum angulus per praetorium ad current angle; Cum CXX UVW tres-Phase differences & deg; Phase.
