Internal-model-principle-based specific harmonics repetitive controller for grid-connected PWM inverters (Q1793852)

Summary: This paper analyzes the general properties of IMP-based controller and presents an internal-model-principle-based (IMP-based) specific harmonics repetitive control (SHRC) scheme. The proposed SHRC is effective for specific \(n k \pm m\) order harmonics, with \(n > m \geq 0\) and \(k = 0,1, 2, \ldots\). Using the properties of exponential function, SHRC can also be rewritten into the format of multiple resonant controllers in parallel, where the control gain of SHRC is \(n / 2\) multiple of that of conventional RC (CRC). Therefore, including SHRC in a stable closed-loop feedback control system, asymptotic disturbance eliminating, or reference tracking for any periodic signal only including these specific harmonic components at \(n / 2\) times faster error convergence rate compared with CRC can be achieved. Application examples of SHRC controlled three-phase/single-phase grid-connected PWM inverters demonstrate the effectiveness and advantages of the proposed SHRC scheme.