This paper presents hybrid electric vehicle harmonic analysis for both single and dual traction motor drive systems. First, inverter output and DC-bus harmonics in single sine-triangle pulse width modulated (SPWM) drives are derived analytically, followed by employing both the switching function approach and Simulink simulations. The resulting harmonics are compared for all three approaches to ensure convergence on accurate results. Next, harmonic analysis of space vector modulated (SVM) dual traction motor drive systems is presented, including the effects of switching dead-time. The paper concludes with harmonic mitigation techniques, compared against military standards, and experimental verification.