A method for low cost operation of an energy system

Abstract

The invention relates to a method for operating an energy system (10), which comprises a transmission system operator (100) that enables the transmission of electricity via a high-voltage line; a distribution system operator (200) that enables the distribution of the electricity to end users; and a microgrid operator (300) that enables the management of the distributed electricity, so as to ensure simultaneous operation at both low costs and with balanced loadings on electrical devices such as transformers.

Description

[0001] A METHOD FOR LOW COST OPERATION OF AN ENERGY SYSTEM

[0002] TECHNICAL FIELD

[0003] The invention relates to a method for low costs operating an energy system.

[0004] PRIOR ART

[0005] Electric grid systems have moved away from their centrally-based structures and have become more dynamic and complex through the use of smart grid technologies and renewable energy sources. The fluctuating generation characteristics of renewable energy sources and rapid changes on the consumer side increase the complexity of the electric grid, leading to power imbalances and voltage problems in transmission and distribution systems.

[0006] Since the current grid infrastructure cannot adequately adapt to this new variability, problems arise in the operation of the grid system and the system capacity is strained. An effective collaboration and coordination need has emerged between the Transmission System Operator (TSO), responsible for energy transmission, and the Distribution System Operator (DSO), responsible for energy distribution. In traditional systems, information sharing between the TSO and DSO is limited. The TSO considers only the constraints of the transmission network, while the DSO makes operational decisions based on the constraints of the distribution network. This situation, especially when combined with the uncertainties of renewable energy sources, reduces system efficiency and leads to additional costs. Furthermore, due to the lack of coordination, the DSO may be forced to take unexpected actions based on the TSO's decisions, such as boundary bus voltage, and may have to implement costly measures such as curtailing the output power of distributed energy resources.

[0007] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result. BRIEF DESCRIPTION OF THE INVENTION

[0008] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.

[0009] An object of the invention is to provide a method that allows reduces energy system costs by increasing data sharing between the transmission system operator, the distribution system operator, and the microgrid operator.

[0010] Another object of the invention is to provide a method that reduces energy supplydemand imbalances.

[0011] To achieve all the objects mentioned above and that will emerge from the following detailed description, a method for low costs operating an energy system, which comprises a transmission system operator that enables the transmission of electricity via a high-voltage line; a distribution system operator that enables the distribution of said electricity to end users; and a microgrid operator that enables the management of the distributed electricity. Accordingly, it comprises the steps of obtaining transmission data comprising a boundary bus active / reactive power value, a boundary bus voltage value, and a locational marginal price value by applying a first mathematical optimization process to the transmission system operator, transmitting the transmission data to a first server for sharing with the distribution system operator, repeating the step of obtaining the transmission data until the transmission data reaches a reference transmission data, obtaining, by the distribution system operator, distribution data comprising an active power demand value and a distribution locational marginal price value as a result of a second mathematical optimization process, transmitting the distribution data to a second server for sharing with the microgrid operator to enable the balancing of a load factor according to a peak power limiting contract, repeating the step of obtaining the distribution data until the distribution data reaches a reference distribution data, obtaining, by the microgrid operator, microgrid data comprising an active power demand value and a distribution locational marginal price value as a result of applying a third mathematical optimization process, transmitting the microgrid data to the second server for sharing with the distribution system operator to enable the balancing of a load factor according to a peak power limiting contract, repeating the step of obtaining the microgrid data until the microgrid data reaches a reference microgrid data. Thus, based on the transmission data, distribution data, and microgrid data, the regulation of power flow and energy market between the transmission system operator, the distribution system operator, and the microgrid operator is ensured, thereby operating the energy system at low costs.

[0012] A possible embodiment of the invention is characterized comprising the steps of a first mathematical optimization process, defining the first mathematical optimization process to the transmission system operator, receiving a transmission network data by the transmission system operator via a meter reading unit, obtaining transmission data by applying the transmission network data to a first mathematical equation in order to perform the first mathematical optimization process.

[0013] Another possible embodiment of the invention is characterized comprising the steps of a second mathematical optimization process, defining the second mathematical optimization process to the distribution system operator, receiving a distribution network data by the distribution system operator via a meter reading unit, obtaining distribution data by applying the distribution network data to a second mathematical equation in order to perform the second mathematical optimization process.

[0014] Another possible embodiment of the invention is characterized comprising the steps of a third mathematical optimization process, defining the third mathematical optimization process to the microgrid operator, receiving a microgrid operator data by the microgrid operator via a meter reading unit, obtaining the microgrid data by applying the microgrid operator data to a third mathematical equation in order to perform the third mathematical optimization process.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 shows a schematic view of the energy system. DETAILED DESCRIPTION OF THE INVENTION

[0017] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

[0018] Referring to Figure 1 , the present invention relates to a method for operating an energy system (10) at low costs, which comprises a transmission system operator (100) (TSO) that enables the transmission of electricity via a high-voltage line; a distribution system operator (200) (DSO) that enables the distribution of the electricity to end users; and a microgrid operator (300) (MGO) that enables the management of the distributed electricity.

[0019] As well known in the art, the transmission system operator (100) enables the transfer of electricity received from energy producers to distribution systems and monitors the energy flow in the system by working in coordination with the distribution system operators during this process. The distribution system operator (200), on the other hand, delivers the energy received from the transmission system to end users at lower voltages and communicates with microgrid operators to ensure integration with local microgrids. Microgrid operators, while connected to the distribution system, meet their energy needs from this system; when operating in islanded mode, they contribute to local energy supply security and support demand management. In addition, microgrid operators can perform energy exchange by transferring surplus generation from renewable energy sources to the distribution system.

[0020] The first mathematical optimization process is applied to the transmission system operator (100). In a possible embodiment of the invention, the first mathematical optimization process may be applied to minimize the unit energy generation cost of the transmission system generators. As well known in the art, the said generators are devices that convert mechanical energy into electrical energy to produce electricity.

[0021] In a possible embodiment of the invention, in the first mathematical optimization process, the first mathematical optimization process is defined to the transmission system operator (100), and a transmission network data is received by the TSO (100) via a meter reading unit. In a possible embodiment of the invention, the transmission network data may comprise active / reactive power profiles, transmission network bus connection matrices, and technical data of transmission lines. The meter reading unit may be a smart meter that enables real-time monitoring of electricity consumption, a SCADA system that collects data from various points of energy transmission and distribution networks, or a power analyzer that enables the measurement of power quality and energy consumption.

[0022] After receiving the transmission network data, the transmission network data is applied to a first mathematical equation in order to perform the first mathematical optimization process, thereby obtaining transmission data. In a possible embodiment of the invention, the first mathematical equation may be a power flow model.

[0023] The transmission data comprises a boundary bus active / reactive power value, a boundary bus voltage value, and a locational marginal price value. The transmission data is transmitted to a first server (110) for sharing with the distribution system operator (200). The steps of obtaining the transmission data are repeated until the transmission data reaches a reference transmission data. In a possible embodiment of the invention, the reference transmission data enables the determination of whether the transmission data has reached a steady point. Thus, convergence is achieved when the differences between the process steps are minimized and the change reaches a negligible level, thereby obtaining optimal results. A second mathematical optimization process is applied to the distribution system operator (200). In a possible embodiment of the invention, the second mathematical optimization process may be applied to minimize the unit energy generation cost of the distribution system generators and the power obtained from the TSO (100).

[0024] In a possible embodiment of the invention, in the second mathematical optimization process, the second mathematical optimization process is defined to the distribution system operator (200), and a distribution network data is received by the DSO (200) via a meter reading unit. In a possible embodiment of the invention, the distribution network data may comprise information such as active / reactive power, voltage information, the amount of power obtained from the TSO (100), total power balance, etc.

[0025] The distribution network data is applied to a second mathematical equation in order to perform the second mathematical optimization process, thereby obtaining distribution data. In a possible embodiment of the invention, the distribution data comprises an active power demand value and a distribution locational marginal price value.

[0026] The distribution data is transmitted to a second server (210) for sharing with the microgrid operator (300) to enable the balancing of a load factor according to a peak power limiting contract. Finally, the step of obtaining the distribution data is repeated until the distribution data reaches a reference distribution data. In a possible embodiment of the invention, the peak power limiting contract ensures the reduction of electricity consumption during periods of highest demand. Accordingly, the load factor is maximized. Thus, the DSO (200) regulates the retail electricity market. The reference distribution data may be a maximum power point.

[0027] A third mathematical optimization process is applied to the microgrid operator (300). In a possible embodiment of the invention, the third mathematical optimization process may be applied to minimize the net power obtained from the DSO (200).

[0028] In a possible embodiment of the invention, in the third mathematical optimization process, the third mathematical optimization process is defined to the microgrid operator (300), and a microgrid operator data is received by the MGO (300) via a meter reading unit. In a possible embodiment of the invention, the microgrid operator data may comprise data such as the net power purchased from / sold to the distribution network, and the power generated by a renewable energy source.

[0029] In a possible embodiment of the invention, the microgrid operator data is applied to a third mathematical equation in order to perform the third mathematical optimization process, thereby obtaining the microgrid data. In a possible embodiment of the invention, the microgrid data may comprise an active power demand value and a distribution locational marginal price value. The microgrid data is transmitted to the second server (210) for sharing with the distribution system operator (200) to enable the balancing of a load factor according to a peak power limiting contract. In a possible embodiment of the invention, the peak power limiting contract ensures the reduction of electricity consumption during periods of highest demand.

[0030] Finally, the step of obtaining the microgrid data is repeated until the microgrid data reaches a reference microgrid data.

[0031] In a possible embodiment of the invention, "positive" and "negative" PLL (Peak Load Limiting) zones may be defined in order to prevent an increase in power demand during periods of intense energy exchange between the DSO (200) and MGOs (300). For this purpose, maximum power points may be determined for both parties. Thus, these values can be used as references in the subsequent process steps. For example, if at a certain moment the power flow to be exchanged is from the DSO (200) to the MGO (300), this zone may be referred to as a "positive PLL" zone, and if the daily maximum power exchange amount exceeds 80%, a joint consumption constraint may be imposed in this zone. Conversely, if the power flow is from the MGO (300) to the DSO (200), this zone may be referred to as a "negative PLL" zone, and similarly, a joint constraint may be imposed for exchange amounts exceeding 80% of the reverse flow.

[0032] The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention. REFERENCE NUMBERS GIVEN IN THE FIGURE

[0033] 10 Energy system

[0034] 100 Transmission system operator

[0035] 110 First server

[0036] 200 Distribution system operator

[0037] 210 Second server

[0038] 300 Microgrid operator

Claims

CLAIMS1. A method for low costs operating an energy system (10), which comprises a transmission system operator (100) that enables the transmission of electricity via a high-voltage line; a distribution system operator (200) that enables the distribution of said electricity to end users; and a microgrid operator (300) that enables the management of the distributed electricity characterized in that it comprises the steps of;- obtaining transmission data comprising a boundary bus active / reactive power value, a boundary bus voltage value, and a locational marginal price value by applying a first mathematical optimization process to the transmission system operator (100),- transmitting the transmission data to a first server (110) for sharing with the distribution system operator (200),- repeating the step of obtaining the transmission data until the transmission data reaches a reference transmission data,- obtaining, by the distribution system operator (200), distribution data comprising an active power demand value and a distribution locational marginal price value as a result of a second mathematical optimization process,- transmitting the distribution data to a second server (210) for sharing with the microgrid operator (300) to enable the balancing of a load factor according to a peak power limiting contract,- repeating the step of obtaining the distribution data until the distribution data reaches a reference distribution data,- obtaining, by the microgrid operator (300), microgrid data comprising an active power demand value and a distribution locational marginal price value as a result of applying a third mathematical optimization process,- transmitting the microgrid data to the second server (210) for sharing with the distribution system operator (200) to enable the balancing of a load factor according to a peak power limiting contract,- repeating the step of obtaining the microgrid data until the microgrid data reaches a reference microgrid data.

2. A method according to claim 1 , characterized in that it comprises the step of a first mathematical optimization process,- defining the first mathematical optimization process to the transmission system operator (100),- receiving a transmission network data by the transmission system operator (100) via a meter reading unit,- obtaining transmission data by applying the transmission network data to a first mathematical equation in order to perform the first mathematical optimization process.

3. A method according to claim 1 , characterized in that it comprises the step of a second mathematical optimization process,- defining the second mathematical optimization process to the distribution system operator (200),- receiving a distribution network data by the distribution system operator (200) via a meter reading unit,- obtaining distribution data by applying the distribution network data to a second mathematical equation in order to perform the second mathematical optimization process.

4. A method according to claim 1 , characterized in that it comprises the step of a third mathematical optimization process,- defining the third mathematical optimization process to the microgrid operator (300),- receiving a microgrid operator data by the microgrid operator (300) via a meter reading unit,- obtaining the microgrid data by applying the microgrid operator data to a third mathematical equation in order to perform the third mathematical optimization process.

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