Load Disturbance Compensation for Stand-alone Inverters Using an Inductor Current Observer

  • Received : 2016.04.29
  • Accepted : 2016.12.16
  • Published : 2017.03.20


A control scheme for stand-alone inverters that utilizes an inductor current observer (ICO) is proposed. The proposed method measures disturbance load currents using a current sensor and it estimates the inductor current using the ICO. The filter parameter mismatch effect is analyzed to confirm the ICO's controllability. The ICO and controllers are designed in a continuous-time domain and transferred to a discrete-time domain with a digital delay. Experimental results demonstrate the effectiveness of the ICO using a 5-kVA single-phase stand-alone inverter prototype. The experimental results demonstrate that the observed current matches the actual current and that the proposed method can archive a less than 2.4% total harmonic distortion (THD) sinusoidal output waveform under nonlinear load conditions.


Supported by : Korea Institute of Energy Technology Evaluation and Planning(KETEP)


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