The waveforms are basically the same as in a DC/AC inverter, means the low-pass filtered output of the H-bridge is a sine voltage, almost equal to the mains voltage. By making the voltage slightly lower than the mains voltage, a sinusoidal current with energy flow towards the AFE is generated. A series inductor is reducing the pwm frequent current, possibly with the help of an additional LC filter.
The H-bridge is usually operated in a 3-level pwm scheme.