nir-vana innovation network

Control actions in distribution and transmission grids are based on the knowledge of load power response to voltage and frequency variations. These data are available by means of extrapolation of active and reactive power, frequency and voltage measurements. However, long-term historical data or complex mathematical methods are needed for accurate identification of the load. In case of inaccurate or outdated load sensitivity evaluation, which occurs during or after the installation of generation power or now loads, the control actions can be ineffective or even harmful to the grid.

To control such situations more effectively, a German university has developed a method for real-time evaluation of load sensitivity to voltage and frequency variations to enable dynamic control of load consumption in electrical power supply grids.

In this invention, a voltage or frequency perturbation is applied using power electronics and the load sensitivity to voltage or frequency is evaluated in real-time by measuring the power consumption variation of loads. Knowledge of the load sensitivity helps to set a control point, e.g. with a power electronics device, to influence the power consumption by means of frequency or voltage change. The consumption of the grid is shaped by applying such voltage and frequency variations, which in turn influences the power consumption of voltage- and frequency-dependent loads. The control point interacts with the devices in the grid (distributed generation equipped with droop controllers, voltage sensitive loads) and it can vary the power consumption as deemed necessary. If the control point decouples the grid, e.g. for high-voltage direct current systems, smart transformer, back-to-back converters, the frequency variation can be used as well for controlling the load consumption in the grid.

Converter connecting asynchronously grids, e.g. grid-forming converters, can directly change the voltage and frequency in the fed grid and thus interact with the load consumption, while converter connected to the main grid, like grid-feeding or distributed generation converters, can influence the voltage amplitude injecting active or reactive power.

No additional hardware would be required and any power electronics converter can be used for the aforementioned purpose.

Possible applications are in the fields of operation of distribution and transmission grids, more specifically in voltage optimization, power saving, demand response, grid support solutions, load management, or conservation voltage reduction.

The patented technology is offered for license agreements or transfer of rights. This would be suitable, when the industrial partner intends further in-house development of the technology based on the available prototype for its commercialization.

The university involved is open to discuss a research cooperation agreement with industrial partners in order to further develop the prototyped technology together and reach a higher TRL. The goal of such a collaboration could be to generate application specific results based on the available prototype for assessment of the commercial feasibility. The partnering university offers their academic expertise in analysis and control of electrical power supply grids.

Advantages & innovations

The real-time load identification and control offers the following advantages, which are not yet solved or adequately addressed in competing state of the art solutions: - Real-time knowledge of the load sensitivity to voltage and frequency. (State of the art solutions for load voltage and frequency sensitivity identification have long computational times, require historical data, and need assumptions on the load aggregation in the grid.) - Voltage dependent load consumption can be controlled by means of a voltage variation (no communication is needed). - Generator production can be shape by means of controlled frequency variations. Frequency/power droop characteristic are already present in current distributed generator. - The voltage in the grid can be influenced by means of reactive power injection. There is no need for asynchronous connection to achieve the voltage-based load control. - Dynamic control of load consumption is possible without the need for additional hardware, since any power electronics converter can be used.

Stage of development

Prototype available for demonstration

Partner sought

Sought are industrial partners of any size (SME or MNE) involved in the operation of distribution and transmission grids, more specifically in voltage optimization, power saving, demand response, grid support solutions, load management, or conservation voltage reduction for license agreements or research cooperation agreements. The role of the industrial partner for any type of cooperation would be the commercialization of the technology. The patented technology is offered for license agreements (or transfer of rights in case of interest), when an industrial partner intends further in-house development of the technology for its commercialization. The university involved is also open to discuss a research cooperation agreement with industrial partners in order to further develop the prototyped technology together and reach a higher TRL. Research cooperation agreements would usually include an option for the industrial partner to purchase the patent or obtain a license at later stage. The goal of a research cooperation could be to generate application specific results based on the available prototype for assessment of the commercial feasibility. The partnering university offers their academic expertise in analysis and control of electrical power supply grids.