DK201770860A1 - Monitoring unit for an electric panel of a wind turbine - Google Patents

Abstract

The invention relates to a monitoring unit for monitoring an electric panel of a control system for a wind turbine, the monitoring unit comprises a plurality of sensors, and a first power supply, wherein a first dataset is monitored by a first sensor and a second dataset is monitored by a second sensor of the monitoring unit. The first sensor during the first life state is powered by the first power supply, the capacity of which is larger than the energy consumption required for the first sensor to obtain a plurality of measurements during the first life state, and wherein the second sensor during the second life state is powered by a second power supply which is at least indirectly connected to an energy generating device.

Description

Monitoring unit for an electric panel of a wind turbine

Field of the invention

The invention relates to a method of monitoring and a monitoring unit for monitoring a plurality of datasets of an electric panel of a wind turbine a plurality of times during from when the panel is assembled to when the panel is used in operation.

Background of the invention

Today in the wind turbine industry there is a high focus on cost and reliability of all parts of the wind turbine. Therefore, all parties involved from design and development over assembly to control during operation are doing the best to reduce price and maintain the high availability of the wind turbine. Focus has until now been on optimized control and predictive maintenance which are described in a numerous of patent applications.

Data obtained from such systems can be used to control operation of the wind turbine or environment inside the panel and thereby be useful prolonging the lifetime of the panel and equipment hereof.

Summary of the invention [0001] The present invention solves a problem of linking data obtained during transportation with data obtained during operation. This problem is not addressed in the prior art. One example is when something occurs during transportation of the panel which may influence or be linked to performance of the panel in operation. Another example is mapping the route and environment the panel is exposed to during transportation which again can be linked to performance of the panel in operation.

[0002] Therefore, the invention relates to a method of monitoring a plurality of datasets of an electric panel a plurality of times during a time period between time A and time D, the method comprising the steps of: prior to time A, install at least a first and a second sensor in the electric panel, connect at least the first sensor to an energy storage, the capacity of which is larger than the energy consumption required for the

DK 2017 70860 A1 first sensor to obtain a plurality of measurements in the time period between time A and time B. Between time A and time B, by the first sensor obtain a plurality first datasets. Prior to time C, at least indirectly connect at least the second sensor to an energy generating device, facilitating supplying the second sensor with energy in the time period between time C and D. Between time C and D, by a second sensor obtain a plurality of second datasets.

[0003] The complete life of an electric panel is divided in several so-called life states. In this document, the life states are determined by the status of the electric panel i.e. the electric panel is in one life state during manufacturing, another during transportation to site of the wind turbine and another during operation of the wind turbine. In the different life states, different data is advantages to measure and there is different access to e.g. power supply and data communication network.

[0004] The method described above is advantages in that it has the effect, that it allows to acquire data related to the electric panel during all or at least several of these life states.

[0005] Preferably, the first and second sensors are located in an enclosure having suitable openings for the sensors to acquire the data from the electric panel. Mounting the sensors in the same enclosure is advantages in that it has the effect that a plurality of sensors can be installed in one workflow with common external data communication and power supply.

[0006] During the period between time A and time B measurements of the second sensor may not be applicable and in the same way during the period between time C and time D measurements of the first sensor may not be applicable. As an example of a non-applicable measurement made during time A and time B is an ultrasonic measurement for monitoring a high voltage joint in the electric panel. Such measurement is not applicable in that no high voltage exists in the electric panel in the period between time A and time B. An example of a non-applicable measurement made during time C and time D could be monitoring the position or location of the

DK 2017 70860 A1 electric panel. Such measurement is not applicable in that the electric panel during this period is stationary mounted and in use in the wind turbine.

[0007] According to an embodiment of the invention, the electric panel being assembled prior to time A, between time A and time B being transported from location of assembly to site of use, prior to time C being installed at site of use and between time C and time D used in operation at the site of use. Preferably, the site of use is the site of a wind turbine and accordingly the electric panel is used in operation as part of the control of a wind turbine.

[0008] In this document, a dataset is preferably understood as measured data i.e. a plurality of discrete measurements or continuously measured data obtained by a sensor over a period of time. Dataset may also simply be referred to as data. An example of a dataset could be a plurality of position data measurements obtained between time A and time B i.e. in the period the electrical panel has traveled from assembly location to site. Alternatively, or in addition a dataset may comprise a plurality of measurements acquired from different sensors. An example of such dataset could be position data, temperature and humidity monitored in the period an electric panel travels from assembly location to site of e.g. the wind turbine. A dataset may include a measured data and time when the data was measured. Hence by the term dataset should be understood data obtained by a sensor of the monitoring unit related to the electric panel or components hereof.

[0009] According to an advantageous embodiment of the invention, the method further comprising the steps of transmitting the dataset acquired from the first sensor and / or second sensor in real-time by means of a data communication device associated with first sensor and / or second sensor.

[0010] This is advantageous in that it has the effect that live data is available to the receiver of the transmitted data which can be used for tracking and control e.g. of environment inside of the electric panel.

[0011] Data transmitting means may be implemented as a communication device using Wi-Fi, Bluetooth, mobile data, satellite, etc. for communication of data. The data

DK 2017 70860 A1 communication device is preferably implemented on the same printed circuit board as the first sensor is connected to.

[0012] Live or real-time data is understood as data which is transmitted as they are acquired and prepared for transmission.

[0013] According to an advantageous embodiment of the invention, the method further comprising the steps of temporary storing of the data acquired by the first sensor and / or second sensor in a data storage associated with the first sensor and / or second sensor.

[0014] This is advantages in that it has the effect that during periods of time where no data communication is available acquired data is not lost.

[0015] A data storage may be associated with a sensor e.g. by being part of the same sensor kit i.e. mounted on the same printed circuit board. Alternatively, associated may simply be understood as a data communication link can be established between the sensor and the data storage.

[0016] It should be mentioned, that the second sensor may be associated with the same data storage as the first sensor or it may be associated with a second data storage for storage of data acquired by the second sensor.

[0017] According to an advantageous embodiment of the invention, the method further comprising the steps of configuring the second sensor to be in a non-power consuming mode between time A and time B.

[0018] This is advantages in that it has the effect that only the first sensor is consuming power from the energy source while the energy source is not connected to the energy generating device, leading to a reduce capacity needed by the energy storage and thereby a reduction in cost of the energy storage.

[0019] Preferably, the second sensor is in a non-power consuming mode during the entire period between time A and time B, but the time of non-power consuming mode may also only extent during a part of the time between time A and time B.

DK 2017 70860 A1 [0020] In the same way, the first sensor may be in a non-power consuming mode during part of or through the entire period between time C and time D.

[0021] According to an advantageous embodiment of the invention, the method further comprising the step of measuring at least one dataset both in the period between time A and time B and in the period between time C and time D.

[0022] This is advantages in that it has the effect, that during root cause analysis of a future failure, data acquired between time A and time B e.g. during transportation of the electric panel can be used. An example hereof could be temperature or humidity which has impact on lifetime of the electric components of the electric panel. Accordingly, a future failure of a component may be caused by temperature or humidity during transportation exceeding design limits of the component. This link between failure and environment during transportation is only possible to make if data is acquired during transportation i.e. between time A and time B.

[0023] In the same way temperature or humidity during operation can be used for root cause analysis.

[0024] Preferably, data acquired during both time A and time B and between time C and time D is acquired by the same sensor, however e.g. for design reasons two sensors may be used to measure e.g. one temperature sensor may be used during time A and time B and another temperature sensor may be used during time C and time D.

[0025] According to an advantageous embodiment of the invention, the method further comprising the step of time stamping the data either by a data processor of the monitoring unit or by a data processor of the device receiving the acquired data.

[0026] This is advantages in that correlation of different dataset then becomes possible which has the effect that failures can be linked to the time of an occurrence leading to the dataset. An example could be link between position and temperature data which when correlated can link location of panel e.g. on a harbour waiting to be shipped with temperature of the panel waiting on the harbour. If the temperature is too high or too low the correlation may be used to indicate that climate control of the

DK 2017 70860 A1 panels is needed during the waiting period. Climate control could be electric or mechanical such as isolation or other forms for protection from environment.

[0027] Moreover the invention relates to a monitoring unit for monitoring an electric panel of a control system for a wind turbine, the monitoring unit comprises a plurality of sensors, and a first power supply, wherein a first dataset is monitored by a first sensor of the monitoring unit a plurality of times during a first life state of the electric panel, and wherein a second dataset is monitored by a second sensor of the monitoring unit a plurality of times during a second life state of the electric panel, and wherein the first sensor during the first life state is powered by the first power supply comprising an energy storage, the capacity of which is larger than the energy consumption required for the first sensor to obtain a plurality of measurements during the first life state, and wherein the second sensor during the second life state is powered by a second power supply which is at least indirectly connected to an energy generating device.

[0028] During the lifetime of an electrical panel, the electrical panel enters different life states. One life state could be the assembly, another could be the transportation from where it is assembled to the site, yet another could be onsite waiting time until installation, yet another could be installed onsite prior to commissioning of the wind turbine and yet another could be when the wind turbine is in operation after commissioning.

[0029] The first and second power supply energizing the sensors of the measuring unit may be the same. However due to the different locations of the electric panel during the different life states the first sensors are solely powered by the first power supply at least during one life state of the electric panel An example hereof could be during transportation where at least one first sensor is solely powered by a battery.

[0030] Preferably, the components of the monitoring unit are all located in a monitoring enclosure which is advantages in that it has the effect that it is easy to mount the monitoring unit.

[0031] As mentioned the electric panel has several life states starting from when it is assembled, transported to site, arriving on site to it is installed in the appliance it is

DK 2017 70860 A1 designed to e.g. a wind turbine. Especially during transportation and during operation it is advantages to receive the dataset.

[0032] Receiving data during transportation has the effect that it becomes possible to track the panel on its way from assembly site to site (position sensor) and if the panel has been exposed to bumps, been knocked over, etc. (accelerometer) [0033] Receiving data during operation has the effect that it becomes possible to monitor temperature inside the panel which is important for the lifetime of electric components, (ultrasonic) sound and IR images which over time can indicate if errors are emerging.

[0034] It is advantages to receive data over several of these life states in that knowledge of such data has effect that design choices can be verified, root cause analysis of failures can be found in this data, etc.

[0035] According to an advantageous embodiment of the invention, the energy storage is a battery dedicated to supply the components of the monitoring unit with power for at least the estimated time for the shipment of the electric panel.

[0036] This is advantageous in that it has the effect that this size of battery matches the power consumption of one position sensor, one temperature sensor, one accelerometer and one humidity sensor for a period of at least the shipment. Typically, a shipment from assembly to site last for 2-6 weeks but it could be both quicker or slower. Preferably, if the shipment is estimated to take 5 weeks the capacity matches the consumption of the part of the monitoring unit which is to be used during transportation for more than 5 weeks such as for 7 or 8 weeks. This is to be sure that even though transportation is delayed the monitoring unit continues to acquire data.

[0037] Accordingly, this size of battery enables performing measurements and storing and / or transmitting these during the time period where the electric panel is transported from site of assembly to site of operation of the wind turbine.

DK 2017 70860 A1 [0038] Preferably the battery is of the Li-ion type. Preferably the battery is located within the monitoring unit enclosure. As an example of the capacity of the battery could be at least 200mA [0039] According to an advantageous embodiment of the invention, the energy generating device is selected from the list comprising the wind turbine, a solar panel, utility grid or an energy harvesting device.

[0040] This is advantages in that it has the effect that sensors, data communication devices, data storages and the like needed for the acquiring, communication and storing of data is continuously supplied with power.

[0041] According to an advantageous embodiment of the invention, the second sensor is supplied with power from the energy generating device via the energy storage.

[0042] This is advantages in that it has the effect that during periods of time where the energy generating device is not supplying energy, the second sensor can continue to acquire data and store these in the associated data storage.

[0043] Connection of a sensor to an energy generating device should be understood also to include indirectly connection. Hence by powering a sensor via e.g. an utility grid, the sensor is indirectly connected to the energy generating device suppling energy to the utility grid.

[0044] According to an advantageous embodiment of the invention, at least one of the list comprising vibration, temperature and humidity is comprised by both the first dataset and the second dataset.

[0045] Advantages in that it has the effect that change over time these environmental values are measured which can be used for later analysis of failures related to these environmental values.

DK 2017 70860 A1 [0046] Vibrations should be understood as utilization including horizontal and vertical movements, shock (bump) summing up to picture all movements of the panel in which the monitoring unit is installed.

[0047] According to an advantageous embodiment of the invention, the first and second sensors is configured for communicating with a data storage of the monitoring unit.

[0048] Advantages in that it has the effect that measured data can be stored for later transmittal in case data communication is not possible.

[0049] According to an advantageous embodiment of the invention, the monitoring unit is configured for wirelessly transmitting data of the first dataset from the monitoring unit of the electric panel to a server external to the electric panel a plurality of times during the first life state of the electric panel wherein the first life state includes transportation of the electric panel from site of assembly to site of the wind turbine, and wherein the monitoring unit is configured for wirelessly transmitting data of the second dataset from the monitoring unit of the electric panel to a server external to the wind turbine a plurality of times during the second life stated of the electric panel wherein the second life state includes operation of the wind turbine.

[0050] This is advantages in that it has the effect that data may be acquired during transport from location of assembly to site of use of the electric panel.

[0051] Furthermore, it is advantages in that it has the effect that data may be acquired during the entire life time of the wind turbine. It should however be mentioned, that the second life state may terminate after a period of time counted in years (5, 6, ...10, 11, . years) from when the second life state starts.

[0052] According to an advantageous embodiment of the invention, the sensors are low consuming sensors using below 10uA when measuring.

[0053] This is advantages in that it has the effect that the capacity of the energy storage can be reduced or the period of which the first sensor is able to acquire data is prolonged.

DK 2017 70860 A1 [0054] According to an advantageous embodiment of the invention, the measuring unit facilitates pre-processing of acquired data and storage of the pre-processed data in the data storage.

[0055] This is advantages in that it has the effect that only e.g. averaged valued of a plurality of acquired data needs to be sent. Pre-processing may also include FFT analysis of the acquired data.

[0056] According to an advantageous embodiment of the invention, the sensors can be selected from the list comprising microphone, ultrasonic sensor, position sensor, temperature sensor, accelerometer, humidity sensor, IR temperature sensor, ozon sensor, smoke detector and image recorder.

[0057] According to an advantageous embodiment of the invention, the energy storage of the first power supply is selected from the list comprising, batteries, capacitors, solar cells, utility grid, energy harvesting or any combination hereof.

[0058] Moreover, the invention relates to the use of a dataset obtained by a monitoring unit according to any of the claims 7-17 and / or by a method according to any of the claims 1-6 for root cause analysis of failures indicated by dataset obtained during the second life state.

[0059] This is advantageous in that it has the effect that the reason for a failure indicated e.g. by a thermal image obtained during the second life state can be found by e.g. acceleration data obtained during the first life state. The example could be that during transportation the panel has been exposed to vibrations or shock which has loosened an electrical terminal leading to a heat generation.

[0060] According to an advantageous embodiment of the invention, the first dataset information is used for root cause of failures indicated by second dataset information [0061] This is advantageous in that it has the effect that errors observed during operation but caused during transportation can be found. One example is that if during transportation vibrations caused wire connectors to loosen this error may first be observed when the wires conducts current. The vibrations may be what is referred to

DK 2017 70860 A1 as first dataset obtained by an accelerometer of the monitoring unit. The error caused by the loose conductors may be observed from an IR camera (sensor of the monitoring unit establishing second dataset), and the root cause can then be established by looking at the information from the first dataset.

The drawings [0062] For a more complete understanding of this disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts:

Figure 1 illustrates a panel according to an embodiment of the invention,

Figure 2 illustrates components of a panel according to an embodiment of the invention,

Figure 3 illustrates a monitoring unit according to an embodiment of the invention,

Figure 4 illustrates the life time of a panel according to an embodiment of the invention, and

Figure 5 illustrates discrete measurements obtained from the monitoring unit according to an embodiment of the invention.

Detailed description [0063] The invention will be explained in further detail with reference to the drawings and with reference to various non-limiting examples and embodiments as it will be explained in the following.

[0064] Figure 1 illustrates an example of an electric panel 2 (also simply referred to as panel) according to an embodiment of the invention. The door 12 of the electric panel 2 is opened revealing part of the inside of the panel. The panel may be equipped with terminals 13 to which wires 14 of cables 15 can be mounted. From the terminals

DK 2017 70860 A1

13, wires 14 may be routed to the electric components 16 (also referred to as panel equipment) via wire ducts.

[0065] No cables 15 are illustrated in that the panel 2 illustrated in figure 1 is assembled and ready to be transported to the site where it is intended to be put into operation.

[0066] In the upper right corner, a monitoring unit 9 is illustrated.

[0067] Figure 2 illustrates a panel 2 according to an embodiment of the invention where the panel (without door) is mounted on site and in or ready for operation. It is noted that cables 15 are mounted to the panel 2 and terminals 13. Wires 14 are connecting the terminals 13 with the electric components 16 of the panel 2.

[0068] A monitoring unit 9 is also illustrated as connected to a cable 15 which may be a power cable or a data cable.

[0069] Figure 3 illustrates an example of the monitoring unit 9 illustrated on figure 1 and 2. The monitoring unit 9 at least comprise first and second sensors 3, 4, data communication device / interface 5 and energy storage 11 but preferably also data storage 7.

[0070] The elements of the monitoring unit 9 are preferably all comprised by an enclosure which is easy to mount inside the electric panel 2. It can be mounted e.g. by magnets, screws or on a din rail beside the components of the panel.

[0071] Depending on what to measure the monitoring unit 9 is located in the top, middle or bottom of the panel 2. If temperature is important it is preferred to locate the monitoring unit 9 in the top of the panel or close to the panel equipment 16 expected to heat up in case of failure. If an ultrasonic sound is to be measured it is advantageous to located the monitoring unit 9 close to the panel equipment 16 to be monitored.

[0072] It may be advantages to install more than monitoring unit 9 in a panel 2 to be able to obtain line of sight or should between a component to be measured and the monitoring unit 9.

DK 2017 70860 A1 [0073] Although not impossible, it is generally not desired to install sensors external to the monitoring unit 9 and connecting such sensor with a wire to the monitoring unit

9. This is because of the time this would take to install. However special panel design or measuring requirements may require this.

[0074] It is noted that a second sensor 4 is located outside the monitoring unit 9. It is possible to locate both first and second sensors 3, 4 outside the monitoring unit 9 if something to be measured requires this although it is not preferred. With this said, IR image recorders and ultrasonic sensors is preferably located close to the component to be monitored, preferably in line of sight of the component to facilitate as high-quality measurements as possible.

[0075] The elements of the monitoring unit 9 may communicate with each other in various ways. Preferably, the (one or more first and / or second) sensors are part of a sensor kit including both sensor, data storage 7 and data communication interface 5. In this case, only power supply is needed for starting monitoring. Such sensor kit is sometimes referred to as an internet of things device.

[0076] Additional sensors may also be connected to the monitoring unit 9 / sensor kit. It should be mentioned that preferably the enclosure may allow onboard or external sensors to monitor e.g. temperature and humidity through the enclosure e.g. by suitable holes in the enclosure.

[0077] Preferably, the dataset 1 obtained by the sensors are stored in a data storage 7 comprised by the monitoring unit 9. The data storage 7 may e.g. be a ring buffer where data is overwritten as new dataset 1 are stored.

[0078] Preferably, the dataset 1 is pre-processed by a data processor 8 of the monitoring unit 9. Pre-processing may e.g. include averaging, FFT analysis and the like of the obtained dataset 1.

[0079] Preferably, the dataset 1 is communicated to an external server or the like before overwritten by new acquired or pre-processed dataset 1.

DK 2017 70860 A1 [0080] Preferably, the capacity of the data storage 7 is enough to store dataset 1 received over at least one day. In this way, dataset 1 may only be communicated once per day. This is especially advantages during transportation, where the monitoring unit 9 is powered by a standalone / limited capacity power supply / energy storage 11.

[0081] The power supply or more specific the first power supply supplying power during transportation is preferably an energy storage 11 in the form of a battery of the li-on type, however other types may also be used. The main determining factor for the battery is that its capacity is high enough to supply to sensor / sensor kit with power during transportation. In addition, determining factors for the type of battery is the weight and allowed working environment such as operating temperature range.

[0082] Several alternatives exist to batteries including a capacitor bank, energy harvesting devices (based on vibrations or the like) or energy generating devices 6 such as solar cells.

[0083] The power supply or more specific the second power supply supplying power during operation may by the first power supply i.e. the energy storage 11 explained above. However ever when the energy storage 11 is functioning as second power supply it needs to be recharged during operation. Hence, during operation the energy storage 11 is charged thereby being able to continuously supply the sensor /sensor kit with power. Accordingly, the power supplied by the second power supply is generated outside the monitoring unit 9 and either supplied to the energy storage 11 or supplied directly to the sensor / sensor kit and / or other power consuming elements of the monitoring unit 9.

[0084] Accordingly, during operation (between time C and time D) the energy storage 11 is only used as power back up in case the energy generating device is not working or transit for the power generated by the power generating device 6. Hence, the second power supply may be the generator of the wind turbine of which the electric panel 2 is installed, the grid to which the wind turbine is connected or other power generating elements such as a solar panel.

DK 2017 70860 A1 [0085] The direct connection between the second power supply and the monitoring unit 9 via the first power supply i.e. the energy storage 11 is advantageous in that in times where the second power supply is not generating any power, the monitoring unit is powered by the battery.

[0086] As mentioned, the monitoring unit 9 is communicating with an external server

i.e. dataset 1 acquired from the electric panel 2 by the first and second sensors 3, 4 is transmitted to a location outside the electric panel 2 and preferably outside the wind turbine when the electric panel 2 is installed herein.

[0087] Data may be communicated from the monitoring unit 9 via mobile G3, G4, G5, etc. network, satellite, Bluetooth, Wi-Fi, cable, etc. Preferably one data communication protocol / method is used prior to installation of the panel in the wind turbine such as a mobile data connection and another is used when the electric panel 2 is in installed in the wind turbine such as Wi-Fi.

[0088] Figure 3 illustrates how the monitoring unit 9 can be equipped with a wireless data communication interface 5 and connected to a data cable thereby via the internet 17 communicating with the external server 10.

[0089] Figure 4 illustrates the life states of an electric panel 2. The first life state is defined as the period during which the electric panel 2 is being assembled. Assembly is understood as when the electric components, terminals and wire ducts are installed in the electric panel 2. The fist life state ends when the electric panel 2 is ready for shipment i.e. at time A. It should be noted that to be able to get as much data from the panel as possible the monitoring unit 9 is installed or mounted in the electric panel 2 prior to end of the first life state.

[0090] In an embodiment, the monitoring unit 9 may comprise initial data relating to one or more component of the electric panel 2 from birth i.e. dataset 1 collected or uploaded to the monitoring unit 9 during or after assembly of the electric panel 2. As an example, components may be scanned by a data input device of the monitoring unit 9. Examples of scanning could be bar or QR codes, RFID tags and the like. This is advantages especially if initial data of replacement components installed in the panel

DK 2017 70860 A1 is also provided to the monitoring unit 9. This is because then the monitoring unit 9 functions as an electric panel 2 database comprising data of preferably all components of the electric panel 2.

[0091] Further, it might be advantageous if the electronic diagrams or technical specification, service log, etc. could be retrieved by accessing the monitoring unit 9. This is especially true if the monitoring unit 9 is connected to a central server such diagrams, service log and technical specifications can be synchronized either from a central location or from the service person performing service and maintenance in the electric panel 2.

[0092] At least the monitoring unit 9 should be installed prior to time A to be able to obtain data from the time during time A and time B i.e. when the panel is transported to the site where it is to be installed preferably in a wind turbine. Transport is almost always on a truck trailer from assembly location either directly to site or to a harbor where it is moved to a ship for being moved e.g. from Europe to USA. From the receiving harbor, the final part of transport to site is also almost always on a truck trailer.

[0093] Both transportation by ship and truck exposes the panel to bumps and changing temperature and humidity, the level of which are interesting information acquired by the monitoring unit 9. This data is interesting in that they can be used for later root cause analysis, panel design evaluation, evaluation of securing of panel during transportation, etc. In addition, the location of the panel is interesting information to acquire in that the time of different parts of the transportation can be measured and used e.g. for optimized planning of future transportations of other panels. Location data can be acquired by a GPS.

[0094] Then the panel arrives at the site at time B it is often parked for some days or weeks until foundation and maybe also tower is installed. From time B to time C, the panel is moved into the tower and cables are connected to the panel and the panel is powered up.

DK 2017 70860 A1 [0095] During this period, bumps, temperature and humidity is also interesting to measure. Loose electric connections are detectable either by noise or heat, therefore in addition also sound, ultrasound, and / or IR images are relevant to measure because the panel is powered up in this period. On the contrary when the panel arrives on site, the location data is irrelevant in that from this point in time the panel stays on the same location.

[0096] At time C the wind turbine is commissioned and ready for operation. From this point in time to time D, the wind turbine is available for producing energy. During this period a whole range of data is relevant to acquire. This includes temperature and humidity for the reasons mentioned above. In addition, smoke, ozon, sound and IR measurements are relevant to measure. The latter may be used to detect if components including busbars are overheated.

[0097] Further sound is relevant to measure. Sound may be used to detect loose components or tools in the hub or blade, wear out of fans, etc. In addition, ultra sound is relevant to measure. Ultra sound may be used to detect contactor or relay failures, partial discharge, arcing, etc.

[0098] Especially it is advantages to measure IR images (thermography), sound or ultra sound emitted from a high voltage switch gear, transformers, etc. This is because at these high voltage components the effect of failure is extreme damages and danger for persons in the error. By monitoring preferably targeted monitoring of joints, insolation, curving cables, breaker parts, shutter jam, breaker arm bent, breaker misalignment, etc. it is possible to prevent discharge, partial discharge, deterioration, facility damage / losses, injury, etc.

[0099] It is preferably the resonance of electrical frequencies of e.g. 50Hz or 60Hz or electrical harmonics hereof which are measured. These resonances or harmonics hereof may occur due to mechanical vibrations or looseness in hardware breakers, external factors such as animals, plants or human errors.

[0100] The fifth period is the period after time D where the wind turbine and thereby the panel is taken out of operation. Normally in this period nothing is interesting to

DK 2017 70860 A1 measure except for location and may be temperature and humidity. The latter may be interesting if the panel or parts hereof should be reused in other panels or wind turbines.

[0101] It is noted that dataset 1 (also simply referred to as data) can be referred to as first dataset 1a from prior to time A to after timer D whereas dataset 1b can be referred to as second dataset 1b only from time B preferably from time C and after time D. Whether a dataset 1 is referred to as first or second dataset 1a, 1b is determined by whether it is a first sensor 3 or a second sensor 4 obtaining the dataset 1.

[0102] The definition of a first sensor 3 is that it is supplied by power from the energy storage 11 in the time prior to time C preferably prior to time B. The first sensors 3 may after time B/C be supplied as the second sensors 4 from the energy storage 11, which now indirectly is connected to an energy generating device 6 or power directly from the energy generating device 6. The definition of a second sensor 4 is that it is not powered until after time C preferably after time B. Summing up, sensors powered and measuring during transportation (between time A and time B) are referred to as first sensors 3 and sensors powered and measuring during operation (between time C and time D) are defined as second sensors 4. With this said first sensors 3 may also be powered and measure also during operation.

[0103] From the above it is evident, that monitoring of an electric panel 2 is advantages in that it has the effect that panel design and transport can be evaluated based on dataset 1 acquired from panels in the field i.e. not on manufactures data, simulations, etc.

[0104] Accordingly, in relation to guarantees from a panel manufactures perspective the monitoring of temperature and vibrations during transportation can be used to state that e.g. temperature has been too high and therefore the manufacture cannot guarantee the normal lifetime of the panel.

[0105] Measurements performed by the monitoring unit 9, can be made either continuous or discrete. Typically, discrete measurements i.e. measurements taken with a certain time interval is preferred in that this reduces the energy consumption of the

DK 2017 70860 A1 measuring unit and amount of data to be handled. Discrete measurements are also sometimes referred to as snapshot measurements.

[0106] A plurality of discrete measurements is made e.g. during one second. Then a period of time passes of e.g. one hour before another set of data is obtained and so on. These successively obtained dataset 1 can be used to generate or determine a development in measurements and thereby of the monitored component. One way of analyzing development in measurements is by use of Fast Fourier Transformation of the dataset 1. Naturally, the snap shots can also be used to determine the real time state of health of a component.

[0107] The time interval between two successive measurements may be predetermined to a duration of e.g. between one minute and one hour or more. Alternatively, the time interval can be dynamic so that when measurements do not indicate potential failures the time intervals are longer and if measurements indicates potential failure, the time intervals are shorter.

[0108] In continuation hereof, transmittal of data from the monitoring unit 9 could be based on the measurements, so that if no indication of failure is present, then data is sent with low frequency. Whereas if measurements indicate failure, data is sent with a higher frequency (more often), which also is a way to reduce the amount of data to be processed.

[0109] Measurements obtained by the measuring unit can be used for many purposes. One is as input to monitoring algorithm training when obtained between time C and time D i.e. during operation. If data from the monitoring unit 9 indicates a potential error, this error could also be indicated by a monitoring algorithm and if not, the monitoring algorithm may need an update.

[0110] Further, the measurements may be used for root course analysis, service planning and feedback to panel designers. The latter is useful information of how components perform in the environment of the wind turbine and thereby if higher or lower quality components may be used in future panel designs.

DK 2017 70860 A1 [0111] In the above description, various embodiments of the invention have been described with reference to the drawings, but it is apparent for a person skilled within the art that the invention can be carried out in an infinite number of ways, using e.g. the examples and embodiments disclosed in the description in various combinations, and within a wide range of variations within the scope of the appended claims.

List

1. Dataset (1a, 1b)

2. Electric panel

3. First sensor

4. Second sensor

5. Data communication / interface device

6. Energy generating device

7. Data storage

8. Data processor (8a, 8b)

9. Monitoring unit

10. External device

11. Energy storage

12. Door

13. Terminals

14. Wires

15. Cables

16. Panel equipment

17. Internet

Claims (19)

1. Patent claims

   1. A method of monitoring a plurality of datasets 1 of an electric panel 2 a plurality of times during a time period between time A and time D, the method comprising the steps of:

   - prior to time A o install at least a first and a second sensor (3, 4) in the electric panel 2 o connect at least the first sensor 3 to an energy storage 5, the capacity of which is larger than the energy consumption required for the first sensor (3) to obtain a plurality of measurements in the time period between time A and time B

   - between time A and time B o by the first sensor (3) obtain a plurality first dataset (1a)

   - prior to time C, o at least indirectly connect at least the second sensor (4) to an energy generating device (6), facilitating supplying the second sensor (4) with energy in the time period between time C and D

   - between time C and D o by a second sensor (4) obtain a plurality of second datasets (1b).
2. 2. A method according to claim 1, wherein the method further comprising the steps of transmitting the dataset (1) acquired from the first sensor and / or second sensor (3,4) in real-time by means of a data communication device (5) associated with first sensor and / or second sensor (3,4).
3. 3. A method according to claim 1 or 2, wherein the method further comprising the steps of temporary storing of the data acquired by the first sensor and / or second sensor (3, 4) in a data storage (7) associated with the first sensor and / or second sensor (3,4).
4. 4. A method according to any of the proceeding claims, wherein the method further comprising the steps of configuring the second sensor (4) to be in a non-power consuming mode between time A and time B.

   DK 2017 70860 A1
5. 5. A method according to any of the proceeding claims, wherein the method further comprising the step of measuring at least one dataset (1) both in the period between time A and time B and in the period between time C and time D.
6. 6. A method according to any of the proceeding claims, wherein the method further comprising the step of time stamping the data either by a data processor (8a) comprised by a monitoring unit (9) or by a data processor (8b) of the device receiving the acquired data (10).
7. 7. A monitoring unit (9) for monitoring an electric panel (2) of a control system for a wind turbine, the monitoring unit (9) comprises a plurality of sensors (3, 4), and a first power supply, wherein a first dataset (1a) is monitored by a first sensor (3) of the monitoring unit (9) a plurality of times during a first life state of the electric panel (2), and wherein a second dataset (1b) is monitored by a second sensor (4) of the monitoring unit (9) a plurality of times during a second life state of the electric panel (2), wherein the first sensor (3) during the first life state is powered by the first power supply comprising an energy storage (11), the capacity of which is larger than the energy consumption required for the first sensor (3) to obtain a plurality of measurements during the first life state, and wherein the second sensor (4) during the second life state is powered by a second power supply which is at least indirectly connected to an energy generating device (6).
8. 8. A monitoring unit according to claim 7, wherein the energy storage (11) is a battery dedicated to supply the components of the monitoring unit (9) with power for at least the estimated time for the shipment of the electric panel (2).

   DK 2017 70860 A1
9. 9. A monitoring unit according to claim 7 or 8, wherein the energy generating device (6) is selected from the list comprising the wind turbine, a solar panel, utility grid or an energy harvesting device.
10. 10. A monitoring unit according to any of the claims 7-9, wherein the second sensor (4) is supplied with power from the energy generating device via the energy storage (11).
11. 11. A monitoring unit according to any of the claims 7-10, wherein at least one of the list comprising vibration, temperature and humidity is comprised by both the first dataset (1a) and the second dataset (1b).
12. 12. A monitoring unit according to any of the claims 7-11, wherein the first and second sensors are configured for communicating with a data storage (7) of the monitoring unit (9).
13. 13. A monitoring unit according to any of the claims 6-12, wherein the monitoring unit (9) is configured for wirelessly transmitting data of the first dataset (1a) from the monitoring unit (9) of the electric panel (2) to a server (10) external to the electric panel (9) a plurality of times during the first life state of the electric panel (2) wherein the first life state includes transportation of the electric panel (2) from site of assembly to site of the wind turbine, and wherein the monitoring unit (9) is configured for wirelessly transmitting data of the second dataset (1b) from the monitoring unit (9) of the electric panel (2) to a server (10) external to the wind turbine a plurality of times during the second life stated of the electric panel (2) wherein the second life state includes operation of the wind turbine.
14. 14. A monitoring unit according to any of the claims 6-13, wherein the sensors (3, 4) are low consuming sensors using below 10uA when measuring.

    DK 2017 70860 A1
15. 15. A monitoring unit according to any of the claims 6-14, wherein the measuring unit (9) facilitates pre-processing of acquired data and storage of the pre-processed data in the data storage (7).
16. 16. A monitoring unit according to any of the claims 6-15, wherein the sensors (3, 4) is selected from the list comprising microphone, ultrasonic sensor, position sensor, temperature sensor, accelerometer, humidity sensor, IR temperature sensor, ozon sensor, smoke detector and image recorder.
17. 17. A monitoring unit according to any of the claims 6-16, wherein the energy storage (11) of the first power supply is selected from the list comprising, batteries, capacitors, solar cells, utility grid, energy harvesting or any combination hereof.
18. 18. Use of a dataset (1) obtained by a monitoring unit according to any of the claims 7-17 and / or by a method according to any of the claims 1-6 for root cause analysis of failures indicated by dataset (1) obtained during the second life state.
19. 19. Use of a dataset (1) according to claim 18, wherein first dataset (1a) information is used for root cause of failures indicated by second dataset (1b) information.