Abstract: An electrical interconnection system (100) comprises a variable frequency rotary transformer (102) and a control system (104). The control system (104) adjusts an angular position of the rotary transformer (102) so that measured power (P1) transferred from a first electrical system (22) to a second electrical system (24) matches an inputted order power (P0). The rotary transformer (102) comprises a rotor assembly (110) and a stator (112), with the control system (104) adjusting a time integral of rotor speed over time. The control system (104) includes a first control unit (107) and a second control unit (108). The first control unit (107) compares the input order power P0 to the measured power P1 to generate a requested angular velocity signal &ohgr;0.

Abstract: An electrical interconnection system (100) comprises a variable frequency rotary transformer (201) and a control system (104). The control system (104) adjusts an angular position of the rotary transformer (102) so that measured power (P1) transferred from a first electrical system (22) to a second electrical system (24) matches an inputted order power signal (P0). The controller limits the power requested by the power order signal based on measured voltages, e.g., the controller has a power-limit function which overrides the order power signal when a measured power exceeds a limit computed from the measured voltages. The limit function is a fraction of maximum theoretical power.

Abstract: A hydroelectric power generation system (20) generates electrical power for an electrical utilization system (72). A controller (42) obtains a requested output electrical power level from a hydro-turbine unit (70) by using a signal indicative of water head (h.sub.meas) to control speed of an asynchronous rotary converter (50) coupled to the hydro-turbine unit and to control gate position of the hydro-turbine unit. The requested output electrical power level is applied from the hydro-turbine unit via the rotary converter to the electrical utilization system. In one embodiment, the controller (42B) accesses an updatable memory wherein Hydraulic Hill Chart information is stored. In another embodiment, the controller (42C) also includes a real-time automatic governor which uses a signal indicative of ac transmission frequency to the electrical utilization system to control the output electrical power level of the rotary converter.