35results about How to "Improve electromagnetic anti-interference ability" patented technology

The invention discloses a multi-parallel inverter motor speed regulating system and a control method of the multi-parallel inverter motor speed regulating system. The system is formed by connecting multiple inverter modules in parallel. The direct current sides of multiple inverter sub modules are directly connected with a direct current power supply with a direct current bus capacitor in parallel. The alternating current sides of the multiple inverter sub modules are connected with multiple sets of smoothing reactors respectively in series and then directly connected in parallel to drive an alternating current motor. By the adoption of the structure, modularization expansion of the motor speed regulating system is easily conducted, and the fault-tolerance performance of the motor speed regulating system is enhanced. By means of a random SVPWM method based on carrier phase shifting, switching frequency of parallel inverters is equivalently improved, switching subharmonic energy within narrow frequency bands is equalized, the harmonic performance of output currents of the parallel inverters is improved, and electromagnetic interference resistance of the motor speed regulating system is enhanced. By the adoption of a space vector synthetic technology for dynamically allocating SVPWM zero vectors, zero-sequence circulating currents between the parallel inverter modules are effectively eliminated, and normal operation of the system is guaranteed.