Harmonic Current Reduction Control Based on Model Predictive Direct Current Control of IPMSM and Input Grid Circuit

This paper proposes a new inverter control method to reduce the input current harmonics and switching frequency of electrolytic capacitorless inverters for interior permanent magnet synchronous motor (IPMSM) drives. In an electrolytic capacitorless inverter system, the input current oscillates due to a resonance between the grid inductance and DC-link capacitor. Due to the oscillation in the input current caused by the LC resonance, the regulations for input current harmonics are sometimes not satisfied. The proposed method, which adopts a model predictive direct current control (MPDCC) method, reduces the switching frequency and satisfies the input current harmonics regulations IEC61000-3-2. MPDCC predicts the motor and input currents and evaluates them using a cost function to select a voltage vector. The cost function reduces the number of switching times and results in a current response that follows the current reference. The prediction model for input current is constructed using the state equations of the input LC resonance circuit and IPMSM. The effectiveness of the proposed method is confirmed experimentally. Further, the experimental results confirm that the proposed method satisfies the input current harmonics regulation IEC61000-3-2.