A variable speed pumping system includes a generator motor including a frequency converter, in which the variable speed pumping system, in the pumping mode, supply a power command to the generator motor to perform power control, and the power control correction signal generator adds a value obtained by multiplying a signal based on a difference between the power input command and an actual power input measured by a power detector in the pumping mode by a constant gain to a signal based on the deviation and inputs the added value to an integration control element to generate the power control correction signal based on an output signal of the integration control element.

A fluid apparatus includes a hydraulic machine, a rotary electric machine connected to the hydraulic machine, and a power conversion controller that converts power from the rotary electric machine. A non-normal operation is performed in a warning state that differs from a normal state in which a normal operation is continued and an anomalous state in which operation is stopped to continue a stopped condition.

A method of controlling an induction generator is provided connected to a utility grid, the method including: receiving an actual grid frequency; and controlling rotor windings of the generator by a rotor control signal having a rotor winding reference frequency being set in dependence of the actual grid frequency.

A downhole power generation system is disclosed, which includes a turbine generator system. The turbine generator system includes a turbine, a generator coupled with the turbine and having an AC-DC rectifier, and an optimized power control unit. The turbine is driven by flow of a downhole fluid to rotate. The generator converts rotational energy from the turbine to electrical energy and outputting a direct current voltage. The turbine generator system is coupled to a load via the optimized power control unit. The optimized power control unit controls to regulate an output voltage of the generator and provides a regulated output voltage to the load so that the turbine generator system has an optimized power output. An optimized power control method for a downhole power generation system is also disclosed.

This method for stabilizing the rotation speed of a hydraulic machine having S-characteristic and comprising a distributor (9) is adapted to modify a water flow, so that the machine can be coupled to a grid. The method comprises the steps of calculating an orientation of the distributor (9); and orienting the distributor according to the calculated orientation. The method further comprises the steps of providing an electric torque to the machine so as to reach a target speed.

A hydroelectric power generation system includes: a generator driven by the hydraulic turbine; a head adjuster adjusting an effective head of the hydraulic turbine; and a controller cooperatively executing: flow rate control for controlling the generator such that a flow rate in the hydraulic turbine is brought close to a target flow rate; and head adjusting control for adjusting the effective head of the hydraulic turbine using the head adjuster such that the effective head of the hydraulic turbine falls within a first range.

A method of controlling a power generation apparatus and a pumped storage power generation apparatus including a motor directly connected to a rotor of a generator or generator motor, the method performing speed control by providing a guide vane opening degree command to the motor, the guide vane opening degree command being calculated by a rotational speed controller including a proportional control element, an integral control element, and a differential control element, in which a first upper limit limiting function is multiplied by a second upper limit limiting function, the first upper limit limiting function being included in an output runaway prevention circuit of an integral control function provided in the integral control element and being defined according to an output signal of a load limiter.

Systems, methods, and non-transitory computer readable media including instructions for a dual-channel fluid turbine controller. A dual-channel fluid turbine controller includes at least one processor configured to: receive, via an AC channel coupled to an AC output of a fluid turbine, first signals indicating fluctuations in power generated by the fluid turbine operating beneath a grid power supply threshold; access an MPPT protocol; determine a correspondence between the first signals and a portion of the MPPT protocol; apply the portion of the MPPT protocol to a generator of the fluid turbine to generate greater power than would be generated in an absence of the MPPT protocol, wherein the generated power is stored as energy in a capacitor associated with the generator; receive, via a DC channel, second signals indicating a level of energy stored in the capacitor; and use the second signals to determine when to release the stored energy.

Systems, methods, and non-transitory computer readable media including instructions for an aggregated voltage controller for a cluster of fluid turbines. An aggregated voltage controller includes at least one processor configured to: receive a target voltage for the cluster; receive via a plurality of rectifiers, each associated with a different turbine, an indication of a DC voltage associated with each turbine, wherein the DC voltage associated with at least one of the turbines is below the target voltage; and based on the received indications of the DC voltage signals associated with each turbine in the cluster, output a control signal to each of a plurality of DC-DC converters associated with the plurality of rectifiers, each control signal configured to regulate each DC-DC converter to produce a DC output at the target voltage such that combining each DC output in parallel produces an aggregated DC voltage conforming to the target voltage.

This disclosure describes many innovations including but not limited to systems, methods, and non-transitory computer readable media containing instructions for controlling an energy generator. A system for controlling an energy generator includes a detector for sensing an indicator of electrical energy generated by the generator; an energy storage component configured, in a first mode of operation, to store energy generated during operation at a sub-threshold level insufficient for real-time supply to an electrical energy sink; an energy converter configured, in a second mode of operation, to provide energy generated during operation above the threshold level for real-time supply of energy to the electrical energy sink; and a controllable switch, electrically associated with the detector, and configured to alternately toggle between the first mode of operation and the second mode of operation based on the indicator to thereby permit energy generated at the sub-threshold level to be collected and intermittently used.