The present disclosure relates to a reactive power compensation system including a reactive power compensation unit for measuring compensate reactive power, an impedance measurement unit for measuring an impedance value of each of a plurality of loads, and a learning control unit for controlling the reactive power compensation unit based on the measured impedance value.

A system and method are provided for managing flicker generated by a wind farm. Accordingly, the farm controller detects at least one parameter of the wind farm indicative of an output flicker resulting from a synchronized flicker of at least two turbines of the plurality of wind turbines. Upon detecting the parameter, the farm controller generates a command offset for at least one wind turbine of the at least two wind turbines. An operating parameter of the at least one wind turbine is changed based on the command offset so as to de-synchronize the synchronized flicker in the output signals of the at least two wind turbines.

A power quality compensator device and a control method thereof are provided. The power quality compensator device is electrically connected to a power grid and a nonlinear load, and includes a current controller, a converter, a ripple predictor, a processing unit and a voltage controller. The current controller is configured to receive an instruction current and output a switch control signal. The converter is configured to output an output current and an actual DC bus voltage according to the switch control signal. The ripple predictor is configured to receive an intermediate voltage and a first current and output a predicted ripple voltage. The processing unit is configured to output a processing result according to the actual DC bus voltage, the predicted ripple voltage and a reference DC bus voltage. The voltage controller is configured to receive the processing result and output a voltage control signal to the current controller.

A frequency detector detects a system frequency from an AC voltage on an AC power line to which a power conditioner performing system interconnection of a distributed power supply is connected. A power converter is configured to inject lead reactive power or delay reactive power into the AC power line. A controller controls reactive power output from the power converter to output the lead reactive power in response to an increase in the system frequency while outputting the delay reactive power in response to a decrease in the system frequency.

An apparatus for controlling one or more switched high power loads (or heating elements). The apparatus including: one or more switched high power loads (or heating elements), each high power load being powered from a common alternating current power source, and wherein each load is independently switched using a switching signal for zero crossing switching to achieve a desired average power output; the switching signal is generated that comprises a repeated switching sequence; the switching sequence indicates a respective selecting activation for each of the switched high power load over a sequence of half or full cycles.

The disclosure provides a grid-tied power generation system and a grid-tied power fluctuation suppression device and method thereof. The system includes a first direct current source, an inverter, and a power grid. The device includes a second direct current source, connected to a direct current side of the inverter; and a power allocation unit, respectively connected to the second direct current source and the inverter. The power allocation unit obtains a power reference value of the first direct current source and a power feedback value of the first direct current source, calculates an alternating current power reference value and a power reference value of the second direct current source according to the power reference value and the power feedback value, and controls the inverter through the alternating current power reference value and controls the second direct current source through the power reference value of the second direct current source.

A system and method are provided for managing flicker generated by a wind farm. Accordingly, the farm controller detects at least one parameter of the wind farm indicative of an output flicker resulting from a synchronized flicker of at least two turbines of the plurality of wind turbines. Upon detecting the parameter, the farm controller generates a command offset for at least one wind turbine of the at least two wind turbines. An operating parameter of the at least one wind turbine is changed based on the command offset so as to de-synchronize the synchronized flicker in the output signals of the at least two wind turbines.

A power control device for use in an AC power grid for regulating an electrical power a load that is supplied by the AC power grid consumes. The power control device has a frequency sensing functional block for detecting a deviation of the grid frequency from a nominal grid frequency and a logic functional block for performing a load adjustment process during which the power the load consumption is reduced. The load adjustment process is based at least in part on the variation of the frequency of the AC power grid. The load adjustment process is design such that for a plurality of power control devices the individual response produce a grid-wide effect that compensates imbalance between power generation and load in fashion that may reduce unwanted distortion in the AC power grid, such as flicker.

A method estimates a grid state of an electrical power distribution grid having a multiplicity of network sections, in which a central computer arrangement is used to receive measured values from measuring devices. A state estimation device is used to make a prediction of a future grid state, wherein a voltage and a phase angle are respectively ascertained for each network section, and in that a naive Bayes method is used for the prediction.

This disclosure provides a method to limit the post-disturbance node maximum RoCoF by optimizing UC decisions. The node initial RoCoF expressions under common disturbance types, including the load, the line switching, and the generator turbine disturbances, are derived. Then, the piecewise linear relationship between the node initial RoCoF and UC decision variables are obtained. To avoid numerical simulation of the node maximum RoCoF, two analytical constraints, i.e., the node initial RoCoF constraint and the COI maximum RoCoF constraint, are formulated in the UC model.