Distributed multi-energy nanogrid monitoring method and system

Abstract

The present invention discloses a distributed multi-energy nanogrid monitoring method and system, which includes: obtaining the geographical location, energy storage parameters, outdoor temperature and electrolyte temperature of each battery pack of an all-vanadium liquid flow battery energy storage station; searching a preset power generation site management database based on the geographical location to obtain site information of several power generation sites that meet the preset same network relationship; obtaining the load / power consumption information of the local power grid based on the geographical location of the all-vanadium liquid flow battery energy storage station; analyzing the load / power consumption information of the local power grid to obtain 24-hour power consumption change information; analyzing the site information of each power station to obtain 24-hour power generation change and grid connection parameters; obtaining peak power consumption period, low power consumption period and other periods according to the historical 24-hour power consumption change information; each power consumption period performs energy storage and energy storage discharge based on the total power generation and power demand. The present application has the effect of better matching the energy consumption characteristics of the power grid.

Description

Technical Field

[0001] The present application relates to the field of multi-energy nanogrid control technology, and in particular to a distributed multi-energy nanogrid monitoring method and system. Background Art

[0002] It is known that in addition to traditional thermal power and hydropower, electricity also comes from solar power and wind power. Therefore, my country has a great advantage in the diversified utilization of energy. The power generation is relatively abundant and can even be sold to the outside world. However, whether it is solar power generation, hydropower generation, or wind power generation, they are all affected by weather and seasonal factors. The power generation varies throughout the year, the whole month, and even at different times of the same day. During peak power generation, the power grid also needs to store energy through energy storage systems.

[0003] Traditionally, energy storage methods involve pumping water to storage reservoirs high in the mountains and then releasing it back down to generate electricity when needed. This method results in high energy losses and is also subject to large geographical restrictions. Currently, new energy storage technologies have emerged, such as storing energy through all-vanadium liquid flow batteries.

[0004] Compared with energy storage through energy storage reservoirs, the loss of all-vanadium liquid flow batteries is relatively small, relatively unrestricted by geographical location, and is controlled in real time. The time for energy storage and electric energy re-entry into the grid is highly operable, which can better alleviate the pressure on the power grid. Therefore, this application proposes a new technical solution. Summary of the invention

[0005] In order to better match the energy consumption characteristics of the power grid and alleviate the pressure on the power grid, the present application provides a distributed multi-energy nanogrid monitoring method and system.

[0006] In a first aspect, the present application provides a distributed multi-energy nanogrid monitoring method, which adopts the following technical solution:

[0007] A distributed multi-energy nanogrid monitoring method, comprising:

[0008] Obtain the geographical location, energy storage parameters, outdoor temperature, and electrolyte temperature of each battery pack of the all-vanadium liquid flow battery energy storage station;

[0009] Searching a preset power generation site management database based on the geographical location to obtain site information of a number of power generation sites that meet the preset same network relationship; wherein the site information includes identification information, geographical location, power generation parameters and grid connection parameters;

[0010] Obtain load / power consumption information of the local power grid based on the geographical location of the all-vanadium liquid flow battery energy storage station;

[0011] Analyze the load / power consumption information of the local power grid and obtain 24-hour power consumption change information;

[0012] Analyze the site information of each power station to obtain the 24-hour power generation changes and grid-connected parameters;

[0013] According to the historical 24-hour electricity consumption change information, peak electricity consumption period, low electricity consumption period and other periods are obtained;

[0014] During peak electricity demand periods and other times:

[0015] If the total power generation of each power station in the same network relationship is greater than the power demand, a storage reminder will be sent to the operator of the all-vanadium liquid flow battery energy storage station;

[0016] If the total power generation of each power station in the same network relationship is less than the preset low power generation threshold, a network prompt will be sent to the operator of the all-vanadium liquid flow battery energy storage station;

[0017] During low electricity consumption periods:

[0018] If the total power generation of each power station in the same network relationship is greater than the power demand, a preset quota power generation analysis will be performed based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station, and a quota recommendation will be sent to the operator of each power station;

[0019] Based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, temperature compensation correction is performed on the energy nanogrid at each stage.

[0020] Optionally, the temperature compensation correction of the energy nanogrid at each stage is performed based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, which includes:

[0021] The outdoor temperature and the electrolyte temperature are subtracted to obtain the temperature difference;

[0022] If the temperature difference is positive, and the current time is in the transition period between the low power consumption period and the peak power consumption period, or in the transition period between other power consumption periods and the peak power consumption period, the power generation parameters of each power station are called;

[0023] Determine whether to enter the preset high-load power generation state according to the power generation parameters of the power station. If not, it will be regarded as a unit to be increased in power generation quota;

[0024] When the electricity demand reaches the preset power generation increase threshold, a quota increase reminder is sent to the power generation quota unit to be increased.

[0025] Optionally, the temperature compensation correction of the energy nanogrid at each stage is performed based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, which includes:

[0026] If the temperature difference is negative and the next time period matches the peak electricity consumption period, a quota maintenance reminder will be sent to each power station, and during the peak period, the operator of the all-vanadium liquid flow battery energy storage station will be given priority to connect to the grid, until the energy storage parameters reach the preset energy storage lower limit threshold, and then a quota increase reminder will be sent to several power stations.

[0027] Optionally, the site information also includes power generation type;

[0028] If the power generation type of a power station is solar power generation, the sunrise and sunset times are obtained based on the corresponding geographical location and current time;

[0029] According to the sunrise and sunset times and a set of historical grid-connected parameters, the power generation attenuation curve is obtained;

[0030] Based on the preset power supply lower limit threshold and power generation attenuation curve, the efficient power supply period is obtained;

[0031] When the overlap rate between the high-efficiency power supply period and the peak power consumption period is less than the preset staggered time threshold, a high quota prompt will be given to the power station whose power generation type is solar power generation during the non-peak power consumption period.

[0032] Optionally, also include:

[0033] If the power generation type of a power station is solar power generation, real-time weather information is obtained based on the corresponding geographical location;

[0034] In the process of generating the power generation attenuation curve, the weather information corresponding to a set of historical grid-connected parameters is selected to be the same as the current weather information, and the date difference between the two is the smallest.

[0035] Optionally, the preset quota power generation analysis based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station includes:

[0036] If the energy storage parameter indicates that the preset energy storage upper limit warning threshold has been reached, the load rate is sorted based on the power generation parameters of each power station;

[0037] According to the load rate sorting information from high to low, the power generation quota is reduced in sequence and prompts are sent accordingly until the total power generation matches the power demand.

[0038] Optionally, the preset quota power generation analysis based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station includes:

[0039] If the energy storage parameter indicates that it is lower than the preset energy storage upper limit threshold, the duration of the power consumption valley and the current remaining energy storage value are calculated;

[0040] Based on the difference between the total power generation and the power demand in real time, the charging time required to reach the preset energy storage upper limit threshold is calculated in real time;

[0041] If the charging time is greater than the remaining electricity consumption valley time, the power generation quota will be reduced in sequence according to the load rate sorting information from high to low, and prompts will be sent accordingly until the charging time matches the remaining electricity consumption valley time.

[0042] In the second aspect, the present application provides a distributed multi-energy nanogrid monitoring system, which adopts the following technical solutions:

[0043] A distributed multi-energy nano-grid monitoring system comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute any of the above-mentioned distributed multi-energy nano-grid monitoring methods.

[0044] In summary, the present application includes at least one of the following beneficial technical effects:

[0045] 1) During peak hours and other periods of electricity consumption, excess electricity is stored in vanadium liquid flow battery energy storage stations and reconnected to the grid to supplement power supply gaps when necessary;

[0046] 2) During off-peak hours, power generation quotas are allocated in a timely manner, so that each power station reduces its power generation rather than storing and converting excess power output;

[0047] The reason for the above settings is that the electricity consumption is generally low from the late night to the early morning of the next day. If there is a solar power station in the power station during this period, it is relatively unreasonable to store energy;

[0048] 3) Considering the outdoor temperature and the electrolyte temperature of the flow battery, adjust the grid conditions of each power station and the all-vanadium flow battery energy storage station to reduce energy waste;

[0049] In summary, the energy storage monitoring method described in this method can better match the energy consumption characteristics of the power grid and alleviate the pressure on the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a flowchart of this application. DETAILED DESCRIPTION

[0051] The following is combined with Figure 1 This application is described in further detail.

[0052] The embodiment of the present application discloses a distributed multi-energy nanogrid monitoring method.

[0053] Reference Figure 1 ,Distributed multi-energy nanogrid monitoring methods include:

[0054] S1. Obtain the geographical location, energy storage parameters, outdoor temperature, and electrolyte temperature of each battery pack of the all-vanadium liquid flow battery energy storage station.

[0055] Among them, the energy storage parameters in this embodiment mainly include real-time energy storage capacity, maximum energy storage capacity, and energy storage conversion rate.

[0056] The outdoor temperature, taking the box-type energy storage structure as an example, is the temperature outside each energy storage box, which can be obtained by a thermometer. The electrolyte temperature can be obtained by connecting to the flow battery control system.

[0057] It is known that the temperature window of all-vanadium liquid flow batteries is limited, so when the outdoor temperature is too high or too low, active energy consumption and temperature control are required; and the discharge process of liquid flow batteries generates heat; therefore, this method takes it into consideration when building an energy grid, which will be explained in detail later.

[0058] S2. Searching a preset power generation site management database based on the geographical location to obtain site information of a number of power generation sites that meet the preset same network relationship.

[0059] This method aims to optimize the power supply of the power grid, and the all-vanadium liquid flow battery energy storage station is only an energy storage unit. Its more allocation and buffering functions are directly affected by the power station. Therefore, it is necessary to network the various power stations in the area to upload various data to facilitate related work.

[0060] In this embodiment, the data of the power station is uniformly stored in an online power generation site management database. The identification of the same network relationship is exemplified as follows: the power station in City A and the all-vanadium liquid flow battery energy storage station in City A belong to the same network relationship; more specifically, the area to which the electricity produced by a power station is supplied is the same network relationship as the all-vanadium liquid flow battery energy storage station in that area.

[0061] It should be noted that the power stations deployed in this method are secondary power stations, such as solar power stations, small hydro / thermal power stations and other regional small-scale power supply units, rather than core power stations such as the Three Gorges.

[0062] The above-mentioned site information includes identification information (i.e. name, code), geographical location, power generation parameters and grid-connected parameters. The real-time power generation includes the maximum power generation power (amount) and the real-time power generation power (amount). The grid-connected parameters include the grid-connected voltage and other parameters used to calculate the actual output power in addition to the power consumption of the factory.

[0063] S3. Obtain the load / power consumption information of the local power grid based on the geographical location of the all-vanadium liquid flow battery energy storage station. The above data can be obtained by connecting to the backend of the relevant units of the State Grid.

[0064] S4. Analyze the load / power consumption information of the local power grid to obtain 24-hour power consumption change information.

[0065] Analyze the site information of each power station to obtain the 24-hour power generation changes and grid-connected parameters.

[0066] S5. Obtain peak power consumption periods, low power consumption periods and other periods based on the historical 24-hour power consumption change information.

[0067] It is understandable that the determination of peak and valley time periods has corresponding power consumption, and this value can be defined manually.

[0068] S6. Nano-network regulation, specifically:

[0069] During peak electricity demand periods and other times:

[0070] If the total power generation of each power station in the same network relationship is greater than the power demand, a storage reminder will be sent to the operator of the all-vanadium liquid flow battery energy storage station.

[0071] If the total power generation of each power station in the same network relationship is less than the preset low power generation threshold, a network prompt will be sent to the operator of the all-vanadium liquid flow battery energy storage station.

[0072] During low electricity consumption periods:

[0073] If the total power generation of each power station in the same network relationship is greater than the electricity demand, a preset quota power generation analysis will be performed based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station, and a quota recommendation will be sent to the operator of each power station.

[0074] Based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, temperature compensation correction is performed on the energy nanogrid at each stage.

[0075] Based on the above, this method can:

[0076] 1) During peak hours and other periods of electricity consumption, excess electricity is stored in vanadium liquid flow battery energy storage stations and reconnected to the grid to supplement power supply gaps when necessary;

[0077] 2) During off-peak hours, power generation quotas are allocated in a timely manner, so that each power station reduces its power generation rather than storing and converting excess power output;

[0078] The reason for the above settings is that the electricity consumption is generally low from the late night to the early morning of the next day. If there is a solar power station in the power station (detailed description below), it is relatively unreasonable to store energy

[0079] 3) Considering the outdoor temperature and the electrolyte temperature of the flow battery, adjust the grid of each power station and the grid of the all-vanadium flow battery energy storage station to reduce energy waste;

[0080] In summary, the energy storage monitoring method described in this method can better match the energy consumption characteristics of the power grid and alleviate the pressure on the power grid.

[0081] The above-mentioned temperature compensation correction of the energy nanogrid at each stage based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack includes:

[0082] The outdoor temperature and the electrolyte temperature are subtracted to obtain the temperature difference;

[0083] If the temperature difference is positive (e.g., the outdoor temperature is higher than the electrolyte temperature in summer), and the current time is in the transition period between the low-consumption period and the peak-consumption period, or the transition period between other power consumption periods and the peak-consumption period (e.g., the first 30 minutes), the power generation parameters of each power station are called;

[0084] Determine whether to enter the preset high-load power generation state according to the power generation parameters of the power station. If not, it will be regarded as a unit to be increased in power generation quota;

[0085] When the electricity demand reaches the preset threshold for increased power generation, a quota increase reminder will be sent to the units whose power generation quotas are to be increased; the quota amount will be determined by the relevant units of the power grid and all parties involved in the operation based on comprehensive consultation on costs, etc., and will not be elaborated here.

[0086] According to the above settings, when the outdoor temperature is high and the peak of electricity consumption is approaching, each power station can be reminded to increase the power generation in time to reduce the number, duration and power of the all-vanadium liquid flow battery energy storage station being connected to the grid;

[0087] The necessity of the above is because: the all-vanadium liquid flow battery energy storage station generates relatively more heat when it is powered by the nanogrid, and at this time the outdoor temperature is high, so more electricity will be consumed for cooling, resulting in energy waste.

[0088] Furthermore, based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, the energy nanogrid at each stage is temperature compensated and corrected, which also includes:

[0089] If the temperature difference is negative (for example, the outdoor temperature is low in winter, lower than the electrolyte temperature), and the next time period matches the peak electricity consumption period, a quota maintenance reminder will be sent to each power station, and during the peak period, the operator of the all-vanadium liquid flow battery energy storage station will be given priority to connect to the grid, until the energy storage parameters reach the preset energy storage lower limit threshold, and then a quota increase reminder will be sent to several power stations.

[0090] According to the above settings, when the outdoor temperature is low and the peak of electricity consumption is about to begin, the all-vanadium liquid flow battery energy storage station can be used to fill the power supply gap. The advantage of this method is that the all-vanadium liquid flow battery energy storage station generates relatively more heat when supplying power through the nanogrid, which can just supplement the heat of the all-vanadium liquid flow battery energy storage station to maintain the temperature window, thereby reducing the energy consumption loss of the all-vanadium liquid flow battery energy storage station's active heat generation.

[0091] In one embodiment of the method, the site information further includes power generation type.

[0092] If the power generation type of a power station is solar power generation, the sunrise and sunset times are obtained based on the corresponding geographical location and current time. For example, the weather information forecast platform is directly connected;

[0093] According to the sunrise and sunset times and a set of historical grid-connected parameters, the power generation attenuation curve is obtained;

[0094] Based on the preset power supply lower limit threshold and power generation attenuation curve, the efficient power supply period is obtained;

[0095] When the overlap rate between the efficient power supply period and the peak power consumption period is less than the preset time difference threshold (that is, the overlapping part of the two periods accounts for too small a proportion of the total efficient power supply period), a high quota prompt will be given to power stations with solar power generation type during non-peak power consumption periods.

[0096] According to the above configuration, if there is a solar power station in the same network and the local electricity consumption peak is more at night, the solar power station will be prompted to operate at a high load during the day to reduce power generation losses.

[0097] Furthermore, if the power generation type of a power station is solar power generation, real-time weather information is obtained based on the corresponding geographical location;

[0098] In the process of generating the power generation attenuation curve, the weather information corresponding to a set of historical grid-connected parameters is selected to be the same as the current weather information, and the date difference between the two is the smallest.

[0099] Based on the above, it can be seen that a set of historical grid-connected parameters is not randomly selected, but is selected based on the weather, and the data selected is from a recent day with the same weather, thereby reducing interference caused by weather and seasons and improving monitoring accuracy.

[0100] In one embodiment of the method, a preset quota power generation analysis is performed based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station, which includes:

[0101] If the energy storage parameter indicates that the preset energy storage upper limit warning threshold has been reached (i.e., when the energy storage upper limit of the energy storage station is approaching), the load rate is sorted based on the power generation parameters of each power station;

[0102] According to the load rate sorting information from high to low, the power generation quota is reduced in sequence and prompts are sent accordingly until the total power generation matches the power demand.

[0103] According to the above settings, the power generation quota of each power station is relatively reasonable, which helps each power station to reasonably arrange equipment maintenance, retrieval work, etc.

[0104] Furthermore, based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station, a preset quota power generation analysis is performed, which also includes:

[0105] If the energy storage parameter indicates that it is lower than the preset energy storage upper limit threshold, the duration of the power consumption valley and the current remaining energy storage value are calculated;

[0106] Based on the difference between the total power generation and the power demand in real time, the charging time required to reach the preset energy storage upper limit threshold is calculated in real time;

[0107] If the charging time is greater than the remaining electricity consumption valley time, the power generation quota will be reduced in sequence according to the load rate sorting information from high to low, and prompts will be sent accordingly until the charging time matches the remaining electricity consumption valley time.

[0108] According to the above configuration, each power station can supply power at a relatively normal load state and meet the energy storage demand, while reducing overcharging and reducing the loss rate of power station equipment.

[0109] The present application also discloses a distributed multi-energy nanogrid monitoring system.

[0110] A distributed multi-energy nano-grid monitoring system comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute any of the above-mentioned distributed multi-energy nano-grid monitoring methods.

[0111] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A distributed multi-energy nanogrid monitoring method, characterized in that: include: Obtain the geographical location, energy storage parameters, outdoor temperature, and electrolyte temperature of each battery pack of the all-vanadium liquid flow battery energy storage station; Searching a preset power generation site management database based on the geographical location to obtain site information of a number of power generation sites that meet the preset same network relationship; wherein the site information includes identification information, geographical location, power generation parameters and grid connection parameters; Obtain load / power consumption information of the local power grid based on the geographical location of the all-vanadium liquid flow battery energy storage station; Analyze the load / power consumption information of the local power grid and obtain 24-hour power consumption change information; Analyze the site information of each power station to obtain the 24-hour power generation changes and grid-connected parameters; Based on the historical 24-hour electricity consumption change information, we can obtain the peak electricity consumption period, the low electricity consumption period and other periods; During peak electricity demand periods and other times: If the total power generation of each power station in the same network relationship is greater than the power demand, a storage reminder will be sent to the operator of the all-vanadium liquid flow battery energy storage station; If the total power generation of each power station in the same network relationship is less than the preset low power generation threshold, a network prompt will be sent to the operator of the all-vanadium liquid flow battery energy storage station; During low electricity consumption periods: If the total power generation of each power station in the same network relationship is greater than the power demand, a preset quota power generation analysis will be performed based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station, and a quota recommendation will be sent to the operator of each power station; Based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, the energy nanogrid at each stage is temperature compensated and corrected; The temperature compensation correction of the energy nanogrid at each stage is performed based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, which includes: The outdoor temperature and the electrolyte temperature are subtracted to obtain the temperature difference; If the temperature difference is positive, and the current time is in the transition period between the low power consumption period and the peak power consumption period, or in the transition period between other power consumption periods and the peak power consumption period, the power generation parameters of each power station are called; Determine whether to enter the preset high-load power generation state according to the power generation parameters of the power station. If not, it will be regarded as a unit to be increased in power generation quota; When the electricity demand reaches the preset power generation increase threshold, a quota increase reminder is sent to the power generation quota unit to be increased; the energy nanogrid at each stage is temperature compensated and corrected based on the outdoor temperature of the all-vanadium liquid flow battery energy storage station and the electrolyte temperature of each battery pack, which includes: If the temperature difference is negative and the next time period matches the peak electricity consumption period, a quota maintenance reminder will be sent to each power station, and during the peak period, the operator of the all-vanadium liquid flow battery energy storage station will be given priority to connect to the grid, until the energy storage parameters reach the preset energy storage lower limit threshold, and then a quota increase reminder will be sent to several power stations.

2. The distributed multi-energy nanogrid monitoring method according to claim 1 is characterized by: The site information also includes power generation type; If the power generation type of a power station is solar power generation, the sunrise and sunset times are obtained based on the corresponding geographical location and current time; According to the sunrise and sunset times and a set of historical grid-connected parameters, the power generation attenuation curve is obtained; Based on the preset power supply lower limit threshold and power generation attenuation curve, the efficient power supply period is obtained; When the overlap rate between the high-efficiency power supply period and the peak power consumption period is less than the preset staggered time threshold, a high quota prompt will be given to the power station whose power generation type is solar power generation during the non-peak power consumption period.

3. The distributed multi-energy nanogrid monitoring method according to claim 2 is characterized in that: Also includes: If the power generation type of a power station is solar power generation, real-time weather information is obtained based on the corresponding geographical location; In the process of generating the power generation attenuation curve, the weather information corresponding to a set of historical grid-connected parameters is selected to be the same as the current weather information, and the date difference between the two is the smallest.

4. The distributed multi-energy nanogrid monitoring method according to claim 1 is characterized in that: The preset quota power generation analysis based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station includes: If the energy storage parameter indicates that the preset energy storage upper limit warning threshold has been reached, the load rate is sorted based on the power generation parameters of each power station; According to the load rate sorting information from high to low, the power generation quota is reduced in sequence and prompts are sent accordingly until the total power generation matches the power demand.

5. The distributed multi-energy nanogrid monitoring method according to claim 4 is characterized in that: The preset quota power generation analysis based on the energy storage parameters of the all-vanadium liquid flow battery energy storage station and the power generation parameters of each power station includes: If the energy storage parameter indicates that it is lower than the preset energy storage upper limit threshold, the duration of the power consumption valley and the current remaining energy storage value are calculated; Based on the difference between the total power generation and the power demand in real time, the charging time required to reach the preset energy storage upper limit threshold is calculated in real time; If the charging time is greater than the remaining electricity consumption valley time, the power generation quota will be reduced in sequence according to the load rate sorting information from high to low, and prompts will be sent accordingly until the charging time matches the remaining electricity consumption valley time.

6. A distributed multi-energy nanogrid monitoring system, characterized by: The method comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executes a distributed multi-energy nanogrid monitoring method as claimed in any one of claims 1 to 5.

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