Systems and method to minimize conditions that cause sub-synchronous oscillation (SSOs) associated with series compensated transmission grids. The implementations ensures the correct development of methods and systems that can mitigate sub-synchronous oscillation (SSOs) associated with a series compensated transmission grid and enhance the series compensation efficiency. An example implementation is a network-based SSO mitigation technology, and another example implementation is a generator-based SSO mitigation technology. The discovery and example implementations are applicable to series compensated transmission networks with synchronous generators, induction generators, wind turbines, solar photovoltaic generators, charging stations, battery storage systems, high-voltage DC transmission systems, STATCOMs, inverter-based data centers, and other inverter-based resources.

Methods for detecting power system events in an electrical power system. An example method comprises determining a signal envelope for each of at least first and second power system signals and performing density-based spatial clustering of a series of points formed by combining respective values of the signal envelopes for at least the first and second power system signals. The example method further comprises detecting one or more power system events by identifying outlier points or groups of points in the spatial clustering. Some methods may further comprise automatically classifying power system events by collecting a data set comprising, for each detected power system event, power system signal features corresponding to the detected power system event, and classifying each of the detected power system events using the data set and a machine-learning-based classification algorithm, where said classifying comprises determining a classification label from among two or more predetermined classification labels.

VSG Frequency Control Method, Device and Storage Medium based on Power Correction, belonging to the field of power electronics technology, which addresses the problem of suppressing VSG output power oscillations. The technical solution of the present application corrects the output power P.sub.e(s) and feeds the corrected value back to the control loop to suppress power oscillations. The transfer function of the power correction stage G(s) is flexible and can be configured with appropriate parameters according to the system's inherent phase margin. Additionally, principles for selecting the parameters of the correction coefficients .sub.1 and .sub.2 are also provided. The adjustment coefficients of the power correction stage, the values of .sub.1 and .sub.2 do not affect the effect of the steady-state gain during the transient process. The present application can not only suppress VSG output power oscillations, but also provide a larger inertial support, thereby improving the stability of the VSG system.

A method for performing a start-up of an offshore plant. The offshore plant comprises a power grid, wherein the power grid comprises a power generation source for generating the energy, a load driven by the power generation source and connected to the power grid, a battery energy storage system connected to the power grid and to the load, and a switching and detecting device connected to the power grid. The method comprises the steps of: detecting by the switching and detecting device, a power outage between the load and power grid; and injecting by the battery energy storage system, the energy to the power generation source to start it up, so as to restore the energy conditions on the power grid prior to the power outage. The injecting step provides the re-energization of a busbar connected to the battery energy storage system and a generator connected to a gas turbine.

Detection of sub-synchronous oscillations in an electrical system for identifying, quantifying, and mitigating grid issues associated with large and fast load fluctuations. An Intelligent Electronic Device (IED) of an electrical system detects energy-related signals associated with the electrical system and processes the energy-related data to identify non-harmonic frequencies of interest. Values associated with the identified one or more non-harmonic frequencies of interest are quantified as a function of at least one of power, voltage, and current data. An alert representative of the quantified values exceeding a set of predefined magnitude limits for longer than a threshold duration may be generated.

A grid-connection control method considering the duality of grid-following and grid-forming in renewable energy transmission during seasonal transitions includes: obtaining the short-circuit ratio (SCR) at the renewable energy grid connection point; when the SCR is greater than a preset SCR threshold, invoking a grid-following variable coefficient additional frequency control strategy to modulate the PWM inverter for renewable energy grid connection; and when the SCR is less than the preset SCR threshold, invoking a grid-forming variable coefficient virtual synchronous generator (VSG) control strategy to modulate the PWM inverter. The aim is to address the issue of how to combine grid-following and grid-forming control strategies to adapt to changes in grid strength due to seasonal transitions.

A model predictive virtual synchronous generator inverter control method considering a frequency-movement direction includes: obtaining a current frequency absolute value based on fundamental frequency of an inverter and a steady-state absolute value based on the fundamental frequency of the inverter; determining a frequency-movement state by comparing the above two absolute values: in a state of deviating from the fundamental frequency or a state of regressing to the fundamental frequency; setting a corresponding prediction output horizon according to the frequency-movement state, and constructing a cost function considering the frequency-movement state; and calculating an optimal virtual power increment value based on the cost function, then calculating an optimal virtual power, inputting the optimal virtual power to a swing equation of a virtual synchronous generator, and performing frequency adjustment according to an output value.

A microgrid distributed secondary control method and system based on a virtual synchronous machine is applied to the technical field of microgrid control. The microgrid distributed secondary control method includes: designing a microgrid primary control strategy based on the virtual synchronous machine, and establishing a microgrid distributed secondary control model based on the virtual synchronous machine by combining a speed regulator equation of the virtual synchronous machine; considering nonlinear characteristics of the virtual synchronous machine, based on a deterministic equivalence principle, designing a linearized microgrid distributed secondary control strategy based on the virtual synchronous machine; and based on the deterministic equivalence principle and a Lyapunov theory, proving accuracy of frequency recovery of the linearized microgrid distributed secondary control strategy based on the virtual synchronous machine. The method and system provides inertia support, significantly reduces communication and computing resources, and helps the microgrid to operate safely and stably.

Method for controlling at least one power source (1), the at least one power source (1) supplying electrical power to at least one power consumer (3) via an electrical power supply grid (2), wherein the following steps are carried out: measuring and/or determining electrical quantities, preferably a frequency and a power disturbance, of the power supply grid (2) during a time period where the electric power supply grid (2) is excited and/or perturbed, such that there is a frequency deviation from a nominal frequency of the power supply grid, deriving at least one parameter (H,D,K.sub.P,K.sub.I,K.sub.D) of a dynamic grid response model from measured values and/or determined values of the measurement and/or determination of the electrical quantities of the power supply grid (2), and adapting a control algorithm defining a control response of the at least one power source (1) depending on the at least one parameter (H,D,K.sub.P,K.sub.I,K.sub.D) of the dynamic grid response model.

A resilient power router system with simplified connection to various energy sources, including batteries, renewable energy sources, and broader grid power, as well as various loads, including data centers. The multiport power router dynamically adjusts power provided from the various power sources and to the various loads, especially to for medium voltage applications. The multiport design enables scalability to multi-megawatt (MW) and medium voltage levels.