The system control model of double resonance injection hybrid active power filter (DIHAPF) and mathematical model of voltage source inverter with controller is established based on the structure and operating principle of DIHAPF. The injection branch features are analyzed including the static reactive power compensation capability and dividing capability of harmonic voltages. Stability and harmonic suppression capacity of DIHAPF is analyzed simultaneously. The influence of the parallel resonant circuit resonant frequency to system performance is discussed in detail. Furthermore, the method of designing the resonant frequency of parallel resonant circuit is proposed. The simulation model of DIHAPF is established and simulated on PSIM 6.0 taking nonlinear loads as harmonic current sources. A 6 kV DIHAPF experiment prototype controlled by TMS320F28335 is built. Simulation and experimental results prove the validity of the analysis.