A converter system includes a DC bus for each phase of an input AC power signal; a first switching cell for each phase, including first two active switches coupled in series across the DC bus and forming a first switching cell AC pole therebetween, the first switching cell AC pole being coupled to a respective phase; and a second switching cell for each phase, including second two active switches coupled in series across the DC bus and forming a second switching cell AC pole therebetween. The second switching cell AC poles are coupled to each other to form a flying neutral. One of the first switching cell and the second switching cell switches at a frequency at least an order of magnitude greater than the line frequency. The other of the first switching cell and the second switching cell switches at a frequency approximately equal to the line frequency.

An electro-mechanical kinetic energy storage device includes an input port, an output port, and a tertiary port separate from and magnetically coupled to the input port and the output port. The input port is configured to receive a first input electrical energy from a first electrical source for inducing mechanical energy into the electro-mechanical kinetic energy storage device. The output port is configured output a first converted electrical energy to a first load in which the outputted electrical energy is generated from the induced mechanical energy. The tertiary port is configured to receive a second input electrical energy from a second electrical source for inducing the mechanical energy, and output a second converted electrical energy to a second load, the second converted electrical energy generated from the induced mechanical energy.

An electro-mechanical kinetic energy storage device includes an input port, an output port, and a tertiary port separate from and magnetically coupled to the input port and the output port. The input port is configured to receive a first input electrical energy from a first electrical source for inducing mechanical energy into the electro-mechanical kinetic energy storage device. The output port is configured output a first converted electrical energy to a first load in which the outputted electrical energy is generated from the induced mechanical energy. The tertiary port is configured to receive a second input electrical energy from a second electrical source for inducing the mechanical energy, and output a second converted electrical energy to a second load, the second converted electrical energy generated from the induced mechanical energy.

An electro-mechanical kinetic energy storage device includes an input port, an output port, and a tertiary port separate from and magnetically coupled to the input port and the output port. The input port is configured to receive a first input electrical energy from a first electrical source for inducing mechanical energy into the electro-mechanical kinetic energy storage device. The output port is configured output a first converted electrical energy to a first load in which the outputted electrical energy is generated from the induced mechanical energy. The tertiary port is configured to receive a second input electrical energy from a second electrical source for inducing the mechanical energy, and output a second converted electrical energy to a second load, the second converted electrical energy generated from the induced mechanical energy.