Method for performing start-up of a marine plant without an external energy source - Patents.com

Abstract

A method for performing start-up of an offshore plant, the offshore plant comprising a power grid for supplying and distributing energy, the power grid comprising a power generation source for generating 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 the load, and a transfer detection device connected to the power grid. The method includes the steps of detecting an interruption between the load and the power grid by the transfer detection device, and injecting energy into the power generation source by the battery energy storage system to start the power generation source and restore the energy state of the power grid before the interruption. The injecting step provides re-energization of busbars connected to the battery energy storage system and a generator connected to the gas turbine to start an engine of the gas turbine of the power generation source by power from a battery of the battery energy storage system. The method further includes the step of complementing fluctuations in the power grid through a charging / discharging process of the battery energy storage system.

Description

[Technical field]

[0001] The present disclosure relates to a method for performing start-up of an offshore plant, such as, for example, an isolated power plant, a floating production storage and offloading (FPSO) unit or platform, without an external energy source, and for restoring an initial energy state of the offshore plant after a power outage, i.e., performing a black start of the offshore plant. [Background technology]

[0002] Systems for black-start, islanded power plants are known. In general, an islanded or marine power plant comprises one or more gas turbines (GTs) for supplying electrical energy to the marine plant, a load, such as a generator-driven machine, connected to the gas turbines, and an auxiliary or emergency energy source.

[0003] In particular, an auxiliary energy source such as a diesel generator can act as a power backup for the load and restart the gas turbine in the event of a power outage.

[0004] Thus, if the power supply from the power grid by the gas turbine is interrupted (eg in the case of a power outage), the marine plant uses the energy provided by the diesel generator until energy can be supplied from an external energy source.

[0005] However, in such a system, the energy provided by the diesel generator is less than the energy provided by the power grid under normal operating conditions. Therefore, the energy available for use by the diesel generator to power the loads is limited until the power failure condition is restored. Furthermore, the diesel generator cannot replicate the power conditions of the marine plant before the power failure. Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, to address the above-mentioned problems, an improved method for performing start-up of a marine plant without an external energy source would be welcomed in the art.

[0007] A new method for performing start-up of a marine plant has been discovered and is disclosed herein.

[0008] In one aspect, the subject matter disclosed herein relates to a method for performing start-up of an offshore plant, the offshore plant comprising a power grid for supplying and distributing energy, the power grid comprising a power generation source for generating 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 the load, and a transfer detection device connected to the power grid, the method including detecting an interruption between the load and the power grid by the transfer detection device, and injecting energy into the power generation source by the battery energy storage system to start up the power generation source and restore an energy state of the power grid before the interruption.

[0009] In another aspect, the subject matter disclosed herein relates to the step of powering providing re-energization of bus bars connected to the battery energy storage system and a generator connected to the gas turbine to start an engine of the gas turbine of the power generating source with power from the batteries of the battery energy storage system.

[0010] In another aspect, the method further includes compensating for fluctuations in the power grid through a charging / discharging process of the battery energy storage system.

[0011] In another aspect, the method further comprises a step of comparing the value of each fluctuation in the power network with a predetermined threshold, such that if the value of the fluctuation exceeds the predetermined threshold a detection step is performed or if the value of the fluctuation does not exceed the predetermined threshold a complementation step is performed.

[0012] In another aspect, the subject matter disclosed herein relates to a battery energy storage system comprising a plurality of inverters for converting input direct current to output alternating current, a plurality of filters for reducing disturbances on the supply lines, a connection device, and a plurality of transformers.

[0013] In another aspect, the subject matter disclosed herein is directed to an offshore plant, such as a platform, comprising a power grid for supplying and distributing energy, the power grid comprising a power generation source for generating 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 the load, and a transfer detection device connected to the power grid, the transfer detection device being capable of detecting a power outage between the load and the power grid, and the battery energy storage system being capable of injecting energy into the power generation source to start it up and restore the energy state of the power grid before the power outage.

[0014] In another aspect, the power generation source includes a gas turbine, a generator connected to the gas turbine, and an engine connected to the gas turbine for starting the gas turbine. [Brief description of the drawings]

[0015] A complete understanding of the disclosed embodiments of the present invention and many of the attendant advantages thereof will be readily obtained as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which: [Figure 1] FIG. 1 is a schematic diagram of a battery energy storage system installed in a marine plant according to a first embodiment. [Diagram 2] FIG. 2 illustrates a flow chart of a method for performing start-up of a marine plant using the battery energy storage system of FIG. [Diagram 3] FIG. 3 shows an operational diagram of a battery energy storage system according to the method of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] In the event of a power outage of the marine plant, the power supply from the power grid is cut off. Thus, the marine plant uses energy provided by a diesel generator. The diesel generator operates as a power backup for the marine plant. However, such a diesel generator provides less energy than is required by the power grid in normal operating conditions. According to one aspect of the present invention, a battery energy storage system (BESS) is provided for restoring an initial energy state of the marine plant after a power outage.

[0017] Referring now to the drawings, FIG. 1 shows a schematic diagram of a battery energy storage system or BESS 3 installed on an offshore plant 2, such as an isolated power plant, a floating production storage and offloading (FPSO) unit or platform.

[0018] The marine plant 2 comprises a power grid 20 for supplying and distributing energy to the marine plant 2 , the power grid 20 comprising power generation sources 21 , 22 , 23 for generating energy, and an electrical busbar or busbars 200 .

[0019] According to the present disclosure, there are three power generation sources 21, 22, 23. However, in other embodiments, the marine plant 2 may include a different number of power generation sources 21, 22, 23 and may be located in other locations.

[0020] In particular, each power generation source 21, 22, 23 comprises a power module 211, 221, 231, such as a gas turbine, steam turbine, etc., an engine or gas turbine starter motor 210, 220, 230 connected to the gas turbine 211, 221, 231, and a generator 212, 222, 232 also connected to the gas turbine 211, 221, 231.

[0021] More specifically, each engine 210, 220, 230 is capable of starting an associated gas turbine 211, 221, 231 when powered, while each generator 212, 222, 232 generates electrical energy for any possible need in the marine plant 2.

[0022] The electrical busbar 200 of the power grid 20 comprises a conductor or an assembly of conductors for collecting electrical power from incoming feeders and distributing them to outgoing feeders. In other words, the electrical busbar 200 is a type of electrical junction where all incoming and outgoing currents meet.

[0023] Thus, power distribution in the marine plant 2 is enabled by an electrical busbar 200 connected to each power generation source 21, 22, 23.

[0024] Furthermore, the marine plant 2 further comprises a load 24 connected to the busbar 200 and a battery energy storage system or BESS 3 .

[0025] The load 24 is a generator-driven machine, capable of generating an electric current while being driven, adapted to generate an electric current when activated by the power generation sources 21, 22, 23, for example to supply power to the marine plant 2. In other embodiments, such a load 24 may be a compressor or a pump, as appropriate.

[0026] The battery energy storage system 3 connected to the load 24 and the power grid 20 can restore the energy state of the power grid 20 before a power outage between the load 24 and the power grid 20 .

[0027] An electrical outage (eg, a blackout) involves an interruption or failure of the power supply between loads 24 and power grid 20 .

[0028] In particular, the battery energy storage system 3 comprises a number of rechargeable batteries 30, such as lithium batteries. The batteries 30 of the battery energy storage system 3 make it possible to supply energy to the power generation sources 21, 22, 23, to start them up and to restore the energy state of the power grid 20 before the blackout. In some embodiments, the battery energy storage system 3 can be constituted by several battery packs and batteries interconnected to reach current and voltage target values.

[0029] Additionally, the battery energy storage system 3 further comprises a number of inverters 31 for converting input DC current to output AC current, a number of filters 32 for reducing disturbances on the supply line, a connection device 33 for connecting the battery energy storage system 3 to the engine 201, and a number of transformers 34 connected to the busbar 200. In particular, such components of the battery energy storage system 3 cooperate to convert the electrochemically stored energy of the batteries 30 into a stable AC output at increased voltage required at the interconnection point(s) with the power grid 20.

[0030] Further, as shown in FIG. 1, the battery energy storage system 3 is connected to a busbar 200 of the power grid 20 by a transfer detection device 4 .

[0031] More specifically, the switching detection device 4 includes a detection device (not shown) for detecting a voltage drop on the bus bar 200 due to a power outage occurring between the load 24 and the power grid 20 .

[0032] Furthermore, the switching detection device 4 further comprises an electrical device (not shown), such as a switch, for establishing or interrupting an electrical path between the battery energy storage system 3 and the busbar 200 based on detection by the detection device.

[0033] Thus, when the detection device detects a voltage drop on the busbar 200, the switch establishes an electrical path between the battery energy storage system 3 and the busbar 200 to enable injection of power from the battery storage system 3 into the power grid 20. Alternatively, when the detection device does not detect a voltage drop on the busbar 200, the switch interrupts the electrical path between the battery energy storage system 3 and the busbar 200.

[0034] FIG. 2 illustrates steps of a method 1 for performing a start-up of a marine plant 2 according to the present disclosure.

[0035] 2, in the method 1, a first step 11 is performed in which a power outage occurring between the load 24 and the power grid 20 is detected by the transfer detection device 4. As described above, the transfer detection device 4 can detect any voltage drop on the busbar 200 due to a power outage occurring between the load 24 and the power grid 20.

[0036] Then, a step 12 is carried out to inject energy into the power generation sources 21, 22, 23 and start them up in order to restore the energy state of the power grid 20 before the power outage.

[0037] More specifically, the power-on step 11 provides for re-energization of the busbar 200 connected to the battery energy storage system 3 and the gas turbine generators 212, 222, 232 connected to the gas turbines 211, 221, 231 in order to start the engines 210, 220, 230 of the gas turbines 211, 221, 231 of the power generation sources 21, 22, 23 with power from the battery 30 of the battery energy storage system 3.

[0038] Subsequently, a step 12 is performed of compensating for fluctuations in the power grid 20 during the charging / discharging process of the battery energy storage system 3. The fluctuations in the power grid 20 can be voltage and / or frequency fluctuations.

[0039] Method 1 also includes a step 13 of comparing the value of each fluctuation in power network 20 to a predetermined threshold.

[0040] If the value of the variation exceeds a predefined threshold, a power outage is detected and therefore detection step 10 is performed.

[0041] Alternatively, if the value of the variation does not exceed a predefined threshold, then only a variation or disturbance is detected and the interpolation step 12 is performed.

[0042] FIG. 3 shows an operational diagram of a battery energy storage system 3 according to the method 1 described.

[0043] As mentioned above, on the one hand, the battery energy storage system 3 can compensate 12 for fluctuations in the power grid 20 through the charging / discharging process of its battery 30 .

[0044] On the other hand, the battery energy storage system 3 can input energy to the busbar 200 connected to the gas turbines 211, 221, 231 and the gas turbine generators 212, 222, 232 in order to start the engines 210, 220, 230 of the gas turbines 211, 221, 231 using power from the battery 30.

[0045] An advantage of the present disclosure is that the battery energy storage system restores an initial energy state of a marine plant after a power outage.

[0046] A further advantage of the present disclosure is that it compensates for fluctuations in the power grid throughout the charging / discharging process of the battery energy storage system.

[0047] While aspects of the invention have been described in terms of various specific embodiments, it will be apparent to those skilled in the art that many modifications, changes, and omissions are possible without departing from the spirit and scope of the claims. In addition, unless otherwise specified herein, the order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments.

[0048] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided as an explanation of the present disclosure, not as a limitation of the disclosure. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the scope or spirit of the disclosure. References throughout this specification to "one embodiment" or "an embodiment" or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the disclosed subject matter. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" or "in some embodiments" in various places throughout this specification do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0049] When presenting elements of various embodiments, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be non-exclusive and mean that there may be additional elements other than the listed elements.

Claims

1. 1. A method for performing a start-up of an offshore plant, the offshore plant comprising: - an electric power grid for supplying and distributing energy, the electric power grid comprising a generation source for generating said 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; A switching detection device connected to the power grid, The method further comprising: detecting a power outage between the load and the power grid by the transfer detection device; injecting the energy into the power generation source by the battery energy storage system to start up the power generation source to restore the energy state of the power grid to a state prior to the power outage; the step of turning on provides re-energization of a busbar connected to the battery energy storage system and a generator connected to the gas turbine to start an engine of the gas turbine of the power generation source with the power from the battery of the battery energy storage system; and compensating for fluctuations in the power grid through a charging / discharging process of the battery energy storage system.

2. The method further comprises comparing a value of each of the fluctuations in the power grid to a predetermined threshold, such that: - the detection step is performed if the value of the variance exceeds the predetermined threshold, or The method according to claim 1 , wherein the imputation step is carried out if the value of the variance does not exceed the predetermined threshold.

3. The method of claim 1 , wherein the fluctuations in the power grid are voltage and / or frequency fluctuations.

4. 2. The method of claim 1, wherein the battery energy storage system comprises a plurality of inverters for converting input direct current to output alternating current, a plurality of filters for reducing disturbances on the supply line, a connection device, and a plurality of transformers.

5. An offshore plant such as a platform, - an electric power grid for supplying and distributing energy, the electric power grid comprising a generation source for generating said 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; A switching detection device connected to the power grid, The switching detection device is capable of detecting a power outage between the load and the power grid; The battery energy storage system is capable of injecting the energy into the power generation source to start up the power generation source, thereby restoring the energy state of the power grid to what it was before the power outage.

6. 6. The marine plant of claim 5, wherein the power generation source includes a gas turbine, a generator connected to the gas turbine, and an engine connected to the gas turbine for starting the gas turbine.

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