Patent ID: 7078830

Claim:
A connecting circuit for connecting to an electricity grid an electric generator generating electrical energy, comprising: (a) a current measuring circuit for measuring the current through the connecting circuit; (b) a storage element for storing charge supplied by the generator for at least some period of time; (c) a charge measuring circuit for measuring the amount of stored charge, which circuit is connected to the storage element; (d) a first controllable switch having an open position for disconnecting the electric generator from the electricity grid and a closed position for connecting the electric generator to the electricity grid in accordance with measured current intensity and measured stored charge; (e) a dissipative element; and (f) a second controllable switch connected in parallel with the storage element; wherein: (i) mutual synchronization of the phase of the current generated by the electric generator in the connecting circuit and the phase of the voltage of the electricity grid is created by: (1) the storing of charge supplied by the electric generator in the storage element when the second switch is in the open position; or (2) dissipating charge from the storage element via the dissipative element when the second switch is in the closed position; and (ii) mutual synchronization of the phase of the current generated by the electric generator in the connecting circuit and the phase of the voltage of the electricity grid causes the first switch to close and the second switch to open and exceptional operating conditions in the electricity grid cause the first switch to open and the second switch to close.