Abstract: A method, an apparatus, and a system for monitoring an islanding electricity generation unit are provided. The method includes determining an islanding electricity generation unit in a renewable energy station on the basis of collected electrical capacity at critical electrical nodes of the renewable energy station, and controlling a switch device corresponding to the determined islanding electricity generation unit to sever connection between the electricity generation unit and a collector line. The critical electrical nodes include nodes that have a collecting effect on grid-connected current of the electricity generation units of the renewable energy station, and each collector line being constructed to collect grid-connected current from at least one electricity generation unit and input same into a main transformer of the renewable energy station.

Abstract: The present disclosure provides an in-situ observation system for a bottom boundary layer (BBL) over a shallow-water cohesive seabed and an arrangement method thereof. It establishes a low-cost and easy-operation hydraulic pile foundation system (2), which can ensure the piling depth to achieve the anti-settling and stability. The stainless-steel sticks are assembled freely to construct the interference-free observation unit (1). As the porous discs are used between the feet of the observation unit (1) and the top of the bottom piles, the observation system can be accurately fixed to the pile foundation. It is thus not limited by the self-weight and can integrate various instruments upon requirement. The components in this system can be easily obtained and conveniently maintained. The present disclosure has the advantages of low-cost and stability, can be widely used for long-term in-situ observation of the BBL.

Abstract: A method, an apparatus, and a system for monitoring an islanding electricity generation unit are provided. The method includes determining an islanding electricity generation unit in a renewable energy station on the basis of collected electrical capacity at critical electrical nodes of the renewable energy station, and controlling a switch device corresponding to the determined islanding electricity generation unit to sever connection between the electricity generation unit and a collector line. The critical electrical nodes include nodes that have a collecting effect on grid-connected current of the electricity generation units of the renewable energy station, and each collector line being constructed to collect grid-connected current from at least one electricity generation unit and input same into a main transformer of the renewable energy station.

Abstract: A photovoltaic power plant and a secondary frequency modulation control method therefor are disclosed. The photovoltaic power plant includes a photovoltaic power station and an active power control system, wherein the photovoltaic power station includes a photovoltaic array and a photovoltaic inverter, the photovoltaic inverter being used for converting direct-current electric energy generated by the photovoltaic array into alternating-current electric energy; and the active power control system is used for performing power allocation on the photovoltaic inverter based on a power control AGC instruction value when running data of the photovoltaic power plant meets a pre-set secondary frequency modulation condition, and adjusting an active power output from the photovoltaic inverter based on an AGC instruction value of the photovoltaic inverter subjected to power allocation. The photovoltaic power station can improve the accuracy of power control and the stability of a power system.

Abstract: Methods and apparatuses for controlling reactive power of a wind turbine, and a wind farm are provided. An exemplary method includes: obtaining operation data of single wind turbines in a wind turbine group at the current time point; determining the total maximum capacitive reactive capacity and total minimum inductive reactive capacity, satisfying a safety constraint condition at the next time point, of the wind turbine group; calculating a deviation value of a wind turbine group reactive instruction at the current time point; and updating the wind turbine group reactive instruction on the basis of the acquired, determined, and calculated data so as to perform reactive power control.

Abstract: The present disclosure provides an in-situ observation system for a bottom boundary layer (BBL) over a shallow-water cohesive seabed and an arrangement method thereof. It establishes a low-cost and easy-operation hydraulic pile foundation system (2), which can ensure the piling depth to achieve the anti-settling and stability. The stainless-steel sticks are assembled freely to construct the interference-free observation unit (1). As the porous discs are used between the feet of the observation unit (1) and the top of the bottom piles, the observation system can be accurately fixed to the pile foundation. It is thus not limited by the self-weight and can integrate various instruments upon requirement. The components in this system can be easily obtained and conveniently maintained. The present disclosure has the advantages of low-cost and stability, can be widely used for long-term in-situ observation of the BBL.

Abstract: A method and a control device for adjusting active power of a wind farm, and a controller of a wind farm are provided. The method includes: acquiring an active power increment to be adjusted in the wind farm; determining an active power adjustable amount of the wind farm based on active power adjustable amounts of wind turbines in the wind farm; and determining an active power adjustment amount of each of the wind turbines based on the active power increment to be adjusted in the wind farm and the active power adjustable amount of the wind farm, to adjust active power of each of the wind turbines.

Abstract: The present invention provides a power control method, device and system for a wind power station. The power control method comprises: obtaining running state data of the wind power station and a grid connection point in real time; determining whether the state of the grid connection point meets conditions of secondary frequency modulation according to the running state data; if it is determined that the state of the grid connection point meets the conditions of secondary frequency modulation, determining a limited power instruction value according to a pre-obtained theoretical power value of the wind power station, a given value of automatic power generation control, and a standby active power value reserved for primary frequency modulation; and generating and sending an instruction used for controlling the active power of the wind generating set of the wind power station according to the limited power instruction value.

Abstract: Disclosed are a photovoltaic power plant and a primary frequency modulation control method therefor. The photovoltaic power plant comprises a photovoltaic power plant and an active power control system. The photovoltaic power plant comprises a photovoltaic array and a photovoltaic inverter, the photovoltaic inverter converting direct current electric energy generated by the photovoltaic array into alternating current electric energy. The active power control system is used for determining the variable quantity of active power of a single machine according to an operating state of the photovoltaic inverter when frequency values of grid connection points of the photovoltaic power plant meet a pre-set primary frequency modulation triggering condition, and regulating the active power output by the photovoltaic inverter. According to the disclosed photovoltaic power, the response speed and accuracy of primary frequency modulation of a generator set can be improved.

Abstract: The present invention provides a power control method, device and system for a wind power station. The power control method comprises: obtaining running state data of the wind power station and a grid connection point in real time; determining whether the state of the grid connection point meets conditions of secondary frequency modulation according to the running state data; if it is determined that the state of the grid connection point meets the conditions of secondary frequency modulation, determining a limited power instruction value according to a pre-obtained theoretical power value of the wind power station, a given value of automatic power generation control, and a standby active power value reserved for primary frequency modulation; and generating and sending an instruction used for controlling the active power of the wind generating set of the wind power station according to the limited power instruction value.

Abstract: A photovoltaic power plant and a secondary frequency modulation control method therefor are disclosed. The photovoltaic power plant includes a photovoltaic power station and an active power control system, wherein the photovoltaic power station includes a photovoltaic array and a photovoltaic inverter, the photovoltaic inverter being used for converting direct-current electric energy generated by the photovoltaic array into alternating-current electric energy; and the active power control system is used for performing power allocation on the photovoltaic inverter based on a power control AGC instruction value when running data of the photovoltaic power plant meets a pre-set secondary frequency modulation condition, and adjusting an active power output from the photovoltaic inverter based on an AGC instruction value of the photovoltaic inverter subjected to power allocation. The photovoltaic power station can improve the accuracy of power control and the stability of a power system.

Abstract: Disclosed are a photovoltaic power plant and a primary frequency modulation control method therefor. The photovoltaic power plant comprises a photovoltaic power plant and an active power control system. The photovoltaic power plant comprises a photovoltaic array and a photovoltaic inverter, the photovoltaic inverter converting direct current electric energy generated by the photovoltaic array into alternating current electric energy. The active power control system is used for determining the variable quantity of active power of a single machine according to an operating state of the photovoltaic inverter when frequency values of grid connection points of the photovoltaic power plant meet a pre-set primary frequency modulation triggering condition, and regulating the active power output by the photovoltaic inverter. According to the disclosed photovoltaic power, the response speed and accuracy of primary frequency modulation of a generator set can be improved.