Method for suppressing dc bus volatge resonance caused by film capacitor of permanent magnet synchronous motor

A method for reducing DC bus voltage fluctuations caused by a film capacitor in a permanent magnet synchronous motor, the permanent magnet synchronous motor adopting a (field-oriented control) FOC strategy;

• the method comprising:
• S1. sampling, using a voltage sensing circuit, a total DC bus voltage (Udc) from an inverter in real-time;
• S2. passing the total DC bus voltage (Udc) through a low-pass filter to extract a DC component (Udc0) of the total DC bus voltage;
• S3. obtaining an AC component (Te=P0·ψf×iq - - - (1)) of the total DC bus voltage (Udc) by subtracting the DC component (Udc0) from the total DC bus voltage (Udc):
• ũdc=Udc−Udc0;
• S4. obtaining a reference DC bus voltage (u*dc) by subtracting the AC component (Te=P0·ψf×iq - - - (1)) from the DC component (Udc0):
• u*dc=Udc0−Te=P0·ψf×iq - - - (1);
• and
• S5. passing the reference DC bus voltage (u*dc) to a space vector pulse width modulation (SVPWM) module, thereby performing calculations that generate precise switching signals for the inverter.