Power transfers in nonlinear frequency converters with three commensurable frequencies

For systems with three arbitrarily assigned commensurable frequencies and nonlinear coupling approximated by a truncated power series, the possibility of power transfers depends on the exponents of the polynomial describing the nonlinearity. The applicability of power-frequency relations, which is uncertain when the frequencies are commensurable, also depends on the form of the polynomial. Pertinent criteria and examples are given.