Fan electrical wireless WiFi data security transmission method

Abstract

The invention relates to the technical field of data security transmission, and discloses a fan electrical wireless WiFi data security transmission method, which comprises the following steps: step S101, generating a session key; step S102, calculating to obtain a permutation parameter, and rearranging the indexes of the subcarriers; step S103, executing error correction coding and convolutional code coding; step S104, encrypting to obtain a ciphertext frame; step S105, calculating to obtain a frequency hopping index; and S106, the receiving end recovers the sequence of the subcarriers, and decoding and verification are executed. According to the method, the session key is deeply bound with physical characteristics and mechanical states of equipment, subcarrier dynamic replacement and rotor synchronous frequency hopping technologies are combined, the anti-interception capability and anti-electromagnetic interference performance of a link are enhanced, the series design of error correction coding and convolutional code coding can cope with loss of a whole frame and random dislocation at the same time, data integrity is guaranteed, and the method is suitable for large-scale popularization and application. Therefore, high security, strong anti-interference capability and high real-time transmission of wireless WiFi data are realized.

Description

Technical Field

[0001] This invention relates to the field of data security transmission technology, and more specifically, to a wireless WiFi data security transmission method for wind turbine electrical systems. Background Technology

[0002] Wind turbines are mostly deployed in open outdoor areas. The nacelle contains equipment such as motors, frequency converters, and gearboxes, which generate strong electromagnetic interference during operation. This interference exists in the form of broadband noise or narrowband harmonics, which can easily lead to wireless signal distortion. At the same time, the high-speed rotation of the impeller can periodically block the wireless link, causing momentary signal interruptions; severe nacelle vibration can affect the stability of the wireless module and exacerbate signal fluctuations.

[0003] Traditional wireless transmission solutions are ill-suited for this environment. In terms of security, commonly used encryption keys are weakly correlated with the physical state of the device, allowing attackers to infiltrate the link by replaying historical data or cracking fixed keys. In terms of interference resistance, fixed-frequency transmission is susceptible to narrowband interference, and a single error correction mechanism cannot simultaneously handle frame loss (e.g., due to obstruction) and random misalignment (e.g., due to electromagnetic interference). In terms of real-time performance, data transmission latency fluctuates greatly. Especially when a fault occurs, if the alarm information exceeds the response threshold of the protection system due to transmission delay, the best protection opportunity will be missed, potentially leading to equipment damage.

[0004] In addition, the monitoring data and control commands that wind turbines need to transmit have stringent requirements for integrity and real-time performance. Existing solutions suffer from low data transmission reliability due to the above circumstances, making it difficult to meet industrial-grade safety and control requirements. Summary of the Invention

[0005] This invention provides a method for secure wireless WiFi data transmission for wind turbine electrical systems, thereby solving the technical problems mentioned in the background section.

[0006] This invention provides a method for secure wireless WiFi data transmission for wind turbine electrical systems, comprising the following steps: Step S101: Read the SRAM response on the wind turbine nacelle side, synchronously collect the mechanical vector, and obtain the random number at the sending end and the random number at the receiving end respectively, and then generate the session key through the hash key derivation function; The mechanical vector consists of a 128-bit binary vector representing the impeller angular velocity, the tower top yaw angle, and the root mean square of the nacelle vibration. Step S102: For each subcarrier of an orthogonal frequency division multiplexing symbol, the permutation parameters are obtained by discretizing the instantaneous mechanical phase of the rotor, and a permutation function is constructed to rearrange the subcarrier indices accordingly. The substitution parameters consist of the phase amplification factor and the displacement bias; Step S103: First, perform error correction coding on the frame data, and then perform convolutional coding to obtain the overall redundancy rate; Step S104: Generate encrypted random numbers for the current frame's mechanical vector using a hash function, and then perform AES-GCM encryption on the payload using the session key and additional authentication data to obtain a ciphertext frame; Step S105: Within a five-megahertz channel set with a fixed number of channels, calculate the frequency hopping index and ensure that the frequency hopping period is equal to the rotor mechanical cycle, so that the channel is hopped only once per rotor mechanical cycle. Step S106: At the receiving end, the subcarrier order is restored by inverse mapping according to the permutation function, and error correction coding and decoding, AES-GCM tag verification and cyclic redundancy check are performed in sequence to complete one frame data transmission.

[0007] Furthermore, the SRAM response is represented by a 256-bit binary vector; the three components of the mechanical vector are quantized into 64-bit, 32-bit, and 32-bit binary vectors by 16-bit, 12-bit, and 10-bit digital converters, respectively; both the transmitting and receiving random numbers are represented by 128-bit binary vectors; and the session key is represented by a 256-bit binary vector.

[0008] Furthermore, the instantaneous mechanical phase of the rotor is multiplied by the ratio of 255 to 2π, and then the discretized phase value between 0 and 255 is obtained by rounding down. The square roots of the three components of the mechanical vector are obtained by squaring them separately and taking the square root. The discretized phase value is then divided by 31 and the remainder is taken. The remainder is then added to 1 to obtain the phase amplification coefficient between 1 and 31. The mechanical vector L2 norm is multiplied by 10 and then calculated by rounding down. The displacement bias is then calculated by adding the current loop index, where the total number of loop indices is the same as the total number of subcarriers.

[0009] Furthermore, the permutation function is used to calculate the permuted carrier number of each subcarrier, with the cyclic index being the k-carrier number. The calculation formula is as follows: Where 1≤k≤63, Indicates the phase amplification factor. This represents the displacement bias at the loop index k, and mod represents the modulo function.

[0010] Furthermore, the error correction coding function has 8 information symbols and a total of 10 symbols. The input to the error correction coding function is 8 consecutive frames of raw payload data, and the output is 10 frames of error correction code, consisting of 8 raw information frames and 2 parity frames. The 10 frames of error correction code are input into convolutional coding. The convolutional code consists of two coding units. The first coding unit and the second coding unit multiply each input bit by the first convolution polynomial coefficient and the second convolution polynomial coefficient, respectively, and then perform an XOR operation. Then, each bit of data is concatenated in the cyclic order of the first coding unit and the second coding unit to output 10 frames of convolutionally coded frame data. The first convolution polynomial coefficient is represented by octal 133, and the second convolution polynomial coefficient is represented by octal 171. The code rate of the convolutional code is 1 / 2.

[0011] Furthermore, the overall redundancy rate is equal to the ratio between the number of output frames and the number of input frames of the error correction coding function, multiplied by the reciprocal of the code rate of the convolutional code.

[0012] Furthermore, the current frame's mechanical vector and timestamp are hashed using the BLAKE3 hash function to obtain a fixed-length 256-bit encrypted random number. Then, the fractional part of the encrypted random number is extracted, multiplied by 2 to the power of 96, and rounded down to obtain a 96-bit integer random number. This 96-bit integer random number is then used as a counter. The session key is used as the key, and the additional authentication data is used as auxiliary authentication information. The payload is then encrypted using AES-GCM to obtain a ciphertext frame containing ciphertext and a 128-bit authentication tag.

[0013] Furthermore, the vibration offset is obtained by first rounding down the root mean square of the nacelle vibration, then dividing it by the fixed number of channels and taking the remainder. The fixed number of channels is 16. Then, the discretized phase value is multiplied by a constant 7, added to the vibration offset, and then divided by 16 and taking the remainder to obtain the frequency hopping index, which is between 0 and 15. Starting from the reference center frequency, the product of the frequency hopping index and the channel spacing of 5MHz is added to obtain the transmission carrier frequency. Finally, the frequency hopping period is equal to the mechanical cycle of the impeller rotation.

[0014] Furthermore, the inverse mapping of the permutation function involves the receiver calculating the permutation parameters using the same parameters as the transmitter, then solving for the multiplicative inverse of the phase amplification coefficient, and finally restoring the subcarrier order for each received subcarrier index using the inverse permutation formula.

[0015] Furthermore, the sum of encryption time, subcarrier replacement time, frequency hopping synchronization overhead time, total decoding time, and MAC layer confirmation time is calculated, and then added to the private network transmission time as the alarm response time. If the alarm response time is exceeded, the security execution policy is triggered.

[0016] The beneficial effects of this invention are as follows: By integrating the real-time mechanical status of the wind turbine's hardware physical characteristics with multiple encryption coding mechanisms, this invention achieves high security, strong anti-interference capability, and high real-time transmission of wireless WiFi data; the session key is deeply bound to the physical characteristics and mechanical status of the equipment, and combined with unique random numbers generated based on mechanical vectors and AES-GCM encryption, it effectively resists replay attacks and data tampering; subcarrier dynamic permutation and rotor synchronous frequency hopping technology enhance the link's anti-interception capability and anti-electromagnetic interference performance; the cascade error correction design of RS code and convolutional code can simultaneously cope with frame loss and random bit errors, ensuring data integrity; thus meeting the hard real-time requirements of wind turbine electrical protection, the overall invention balances the reliability and efficiency of data transmission through reasonable redundancy. Attached Figure Description

[0017] Figure 1 This is a flowchart of a wireless WiFi data security transmission method for wind turbine electrical systems according to the present invention. Detailed Implementation

[0018] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0019] It should be noted that, unless otherwise defined, the technical or scientific terms used in one or more embodiments of the present invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in one or more embodiments of the present invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" indicate that the element or object preceding the term encompasses the elements or objects listed following the term and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0020] like Figure 1 As shown, a method for secure wireless WiFi data transmission for wind turbine electrical systems includes the following steps: Step S101: Read the SRAM response on the wind turbine nacelle side, synchronously collect the mechanical vector, and obtain the random number at the sending end and the random number at the receiving end respectively, and then generate the session key through the hash key derivation function; The mechanical vector consists of a 128-bit binary vector representing the impeller angular velocity, the tower top yaw angle, and the root mean square of the nacelle vibration. Step S102: For each subcarrier of an orthogonal frequency division multiplexing symbol, the permutation parameters are obtained by discretizing the instantaneous mechanical phase of the rotor, and a permutation function is constructed to rearrange the subcarrier indices accordingly. The substitution parameters consist of the phase amplification factor and the displacement bias; Step S103: First, perform error correction coding on the frame data, and then perform convolutional coding to obtain the overall redundancy rate; Step S104: Generate encrypted random numbers for the current frame's mechanical vector using a hash function, and then perform AES-GCM encryption on the payload using the session key and additional authentication data to obtain a ciphertext frame; Step S105: Within a five-megahertz channel set with a fixed number of channels, calculate the frequency hopping index and ensure that the frequency hopping period is equal to the rotor mechanical cycle, so that the channel is hopped only once per rotor mechanical cycle. Step S106: At the receiving end, the subcarrier order is restored by inverse mapping according to the permutation function, and error correction coding and decoding, AES-GCM tag verification and cyclic redundancy check are performed in sequence to complete one frame data transmission.

[0021] In one embodiment of the present invention, the SRAM response is represented by a 256-bit binary vector; the three components of the mechanical vector are quantized into 64-bit, 32-bit, and 32-bit binary vectors by 16-bit, 12-bit, and 10-bit digital converters, respectively; the sending random number and the receiving random number are both represented by a 128-bit binary vector; and the session key is represented by a 256-bit binary vector.

[0022] It should be noted that the Physically Unclonable Function (PUF) response of the SRAM (Static Random Access Memory) of the embedded chip (such as MCU or PLC) on the wind turbine nacelle side is read, and an uncopyable physical signature code is generated using the random initial state (0 / 1) of the SRAM cell when the chip is powered on. The random numbers at the sending end and the random numbers at the receiving end are generated by hardware random number generators, such as those based on noise diodes, and the two ends exchange random numbers through the initial handshake frame. According to the above, the length of the binary vector input to the hash key derivation function is 256+128+128+128=640. The hash key derivation function is HKDF. First, the pseudo-random key (256 bits) is extracted from the input 640-bit binary vector using the SHA-256 hash function. The salt value here is empty by default. Then, the pseudo-random key is expanded into a session key, and the ASCII-encoded link identifier and the target key length (256 bits) are added here.

[0023] It should be noted that the impeller angular velocity represents the instantaneous angular velocity of the wind turbine impeller rotation, which is usually obtained in real time by photoelectric encoders or Hall sensors installed on the wind turbine main shaft or gearbox output end; the tower top yaw angle represents the angle of rotation of the wind turbine nacelle around the tower axis, which is usually measured by absolute encoders or tilt sensors installed on the tower top or nacelle slewing support; the nacelle vibration root mean square represents the root mean square value of the wind turbine nacelle vibration signal, reflecting the intensity of the nacelle structure vibration, which is usually obtained by collecting the vibration signal by an accelerometer fixed to the nacelle base, filtering and calculating the root mean square; step S101 generates a unique 256-bit session key that is strongly bound to the wind turbine environment by integrating the wind turbine hardware physical characteristics, real-time mechanical state and double-ended random numbers, providing root key protection for subsequent encryption and transmission.

[0024] In one embodiment of the present invention, the instantaneous mechanical phase of the rotor is multiplied by the ratio of 255 to 2π, and then a discretized phase value between 0 and 255 is obtained by rounding down. The three components of the mechanical vector are squared and summed to obtain the square root of the mechanical vector L2 norm. The discretized phase value is then divided by 31 and the remainder is taken. The remainder is then added to 1 to obtain the phase amplification coefficient between 1 and 31. The mechanical vector L2 norm is multiplied by 10 and then calculated by rounding down. The displacement bias is then calculated by adding the current loop index, where the total number of loop indices is the same as the total number of subcarriers.

[0025] It should be noted that the subcarrier representation of the Orthogonal Frequency Division Multiplexing (OFDM) symbol divides the wireless signal into 64 parallel sub-frequency channels, each carrying data, which together form a transmission unit, thereby improving transmission efficiency and anti-interference capability; that is, the total number of subcarriers is 64, and the value of the cyclic subscript is between 0 and 63, that is, the displacement bias changes with the cyclic subscript and mechanical state.

[0026] In one embodiment of the present invention, the permuted carrier number of each subcarrier is obtained by calculating the permutation function, with the cyclic index being the k-carrier number. The calculation formula is as follows: Where 1≤k≤63, Indicates the phase amplification factor. This represents the displacement bias at the loop index k, and mod represents the modulo function.

[0027] It should be noted that the 64 subcarriers of the OFDM symbol are dynamically replaced based on the real-time mechanical state of the wind turbine, giving the physical layer of the wireless signal chaotic characteristics, improving the ability to resist multipath interference, enhancing link security, and at the same time not affecting real-time transmission.

[0028] In one embodiment of the present invention, the error correction coding function has 8 information symbols and a total of 10 symbols. The input of the error correction coding function is 8 consecutive frames of raw payload data, and the output is 10 frames of error correction code, consisting of 8 raw information frames and 2 parity frames. The 10 frames of error correction code are input into convolutional code encoding. The convolutional code consists of two coding units. The first coding unit and the second coding unit perform an XOR operation on each input bit and the first 6 bits by the coefficients of the first and second convolution polynomials, respectively. Then, each bit of data is concatenated in the cyclic order of the first coding unit and the second coding unit to output 10 frames of frame data after convolutional coding. The coefficients of the first convolution polynomial are represented in octal as 133, and the coefficients of the second convolution polynomial are represented in octal as 171. The code rate of the convolutional code is 1 / 2.

[0029] It should be noted that the error correction coding function is the Reed-Solomon coding function (RS code). The number of information symbols represents the number of frame data processed in each encoding step, and the total number of symbols represents the total number of frame data output after encoding, including information frames and parity frames. The coefficients of the first convolution polynomial are represented in binary as 1011011, and the coefficients of the second convolution polynomial are represented in binary as... 1111001, the code rate of the convolutional code is 1 / 2, which means the ratio of the number of input bits to the number of output bits, that is, for every 1 bit of data input, the convolutional code outputs 2 bits of data.

[0030] It should be noted that RS codes are mainly designed to address frame loss or sudden errors in wind turbine environments, such as signal interruption caused by blade obstruction or momentary power failure. Its cross-frame processing feature can correct the loss of any two frames out of ten or a symbol error in one frame, ensuring the integrity of continuous data blocks. Convolutional codes, on the other hand, use a two-way coding unit and a 1 / 2 code rate design to cope with random bit errors caused by electromagnetic interference (EMI) in wind turbine environments. The polynomial coefficients ensure a uniform distribution of coding redundancy, and each input bit generates a 2-bit output (code rate 1 / 2). Error detection capability is enhanced by associating historical bits.

[0031] In one embodiment of the present invention, the overall redundancy rate is equal to the ratio between the number of output frames of the error correction coding function and the number of input frames, multiplied by the reciprocal of the code rate of the convolutional code, that is, the overall redundancy rate is equal to 10 / 8×2=2.5, which means that 2.5 bytes of data need to be sent for every 1 byte of valid data transmitted, thus balancing reliability and transmission efficiency through reasonable redundancy.

[0032] In one embodiment of the present invention, the current frame mechanical vector and the timestamp are hashed using the BLAKE3 hash function to obtain a fixed-length 256-bit encrypted random number. Then, the fractional part of the encrypted random number is extracted, multiplied by 2 to the power of 96, and rounded down to obtain a 96-bit integer random number. This 96-bit integer random number is then used as a counter. The session key is used as the key, and the additional authentication data is used as auxiliary authentication information. The payload is then encrypted using AES-GCM to obtain a ciphertext frame containing ciphertext and a 128-bit authentication tag.

[0033] It should be noted that the additional authentication data refers to a bit string that does not need to be encrypted but must participate in integrity verification. This string is formed by concatenating the sequence number, timestamp, rotor instantaneous mechanical phase, and CRC-32 (32-bit cyclic redundancy check algorithm) in a fixed order in the data frame header before encryption. The payload output by the convolutional code is encrypted with AES and has the same length as the plaintext, ensuring data confidentiality and preventing attackers from directly reading the content. The 128-bit authentication tag is used by the receiving end to verify the integrity (whether it has been tampered with) and authenticity (whether it comes from a legitimate sender). The BLAKE3 hash ensures that the encrypted random number cannot be deduced from the mechanical state and is evenly distributed, effectively preventing attackers from predicting subsequent encrypted random numbers.

[0034] In one embodiment of the present invention, the root mean square of the nacelle vibration is first rounded down, then divided by the fixed number of channels and the remainder is taken to obtain the vibration offset, where the fixed number of channels is 16. Then, the discretized phase value is multiplied by a constant 7, added to the vibration offset, and then divided by 16 and the remainder is taken to obtain the frequency hopping index, which has a value range between 0 and 15. Starting from the reference center frequency, the product of the frequency hopping index and the channel spacing of 5MHz is added to obtain the transmit carrier frequency. Finally, the frequency hopping period is equal to the mechanical cycle of the impeller rotation (i.e., the time for the impeller to rotate one revolution). The reference center frequency is the starting reference frequency of the frequency hopping channel. For example, if the reference center frequency is 2400MHz, then the center frequencies of the 16 channels are 2400MHz, 2405MHz, ..., 2475MHz, which makes it easy for the receiver to quickly locate the current channel according to the frequency hopping index.

[0035] It should be noted that the fixed number of channels and channel spacing are custom parameters. Industrial WiFi commonly uses the 2.4GHz or 5GHz frequency band bandwidth. The total bandwidth of 16 channels with 5MHz intervals is 80MHz. 16 channels are chosen here because they can cover the main interference frequency bands and avoid the cost of the equipment's RF module from soaring due to too many channels. If 32 channels are used, a higher precision DDS frequency synthesizer is required, and vibration in the fan environment may cause phase noise degradation. By driving frequency hopping through mechanical state, the carrier frequency changes dynamically with the impeller movement, and the period is synchronized with the impeller. The transmission and reception are easy to align, which improves anti-interference capability and enhances link security. It is suitable for industrial scenarios with strong electromagnetic interference from fans and the need to prevent interception.

[0036] In one embodiment of the present invention, the inverse mapping of the permutation function is to obtain the permutation parameters by the receiver using the same parameters as the transmitter, and then solve for the multiplicative inverse of the phase amplification coefficient. The subcarrier order is then restored for each received subcarrier index using the inverse permutation formula.

[0037] It should be noted that the inverse permutation formula is to process the difference between the index and the displacement using the multiplicative inverse, and then take the modulus of 64; the error correction coding and decoding consists of deconvolutional coding and RS decoding, where the deconvolutional coding parameters include a constraint length of 7 and a path storage depth of 36, and the input bit stream is restored by backtracking using the Viterbi algorithm; the RS decoding parameters include a code length of 10 and an information bit length of 8, and the original 8 frames of data are restored; the AES-GCM tag verification uses the session key, an integer random number, and additional authentication data to recalculate the authentication tag, and compares it with the received 128-bit authentication tag to verify whether the data has been tampered with or forged; the cyclic redundancy check calculates the 32-bit CRC value of the received data and compares it with the CRC value carried in the additional authentication data to verify the integrity of the data transmission.

[0038] In one embodiment of the present invention, the sum of encryption time, subcarrier permutation time, frequency hopping synchronization overhead time, total decoding time and MAC layer confirmation time is calculated, and then added to the private network transmission time as the alarm response time. If the alarm response time is exceeded, the security execution policy is triggered.

[0039] It should be noted that the frequency hopping synchronization overhead time corresponds to the time consumed in step S105. The private network transmission time can be directly referenced from the longest switching and forwarding delay of the existing network in the site, for example, 4ms. Assuming that the encryption time is about 0.02ms, the subcarrier replacement time is about 0.03ms, the frequency hopping synchronization overhead time is about 0.05ms, the total decoding time is about 0.04ms, and the MAC layer acknowledgment time is about 0.11ms, then the alarm response time is about 4.25ms. The safety execution strategy is that if this time is exceeded, the PLC in the control room will synchronously monitor the fault position. If no ACK is received from the host computer within the preset maximum time, it will also automatically perform safety actions such as shutdown, disconnection, or power reduction, and record the timeout event in the local black box for maintenance and troubleshooting.

[0040] It should be noted that the interval and threshold sizes are set for ease of comparison. The size of the threshold depends on the amount of sample data and the base number set by those skilled in the art for each set of sample data, as long as it does not affect the proportional relationship between the parameter and the quantized value. Furthermore, the above formulas are all dimensionless calculations, and the formulas are derived from software simulations using a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0041] The embodiments of this example have been described above. However, this example is not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of this example, and all of them are within the protection scope of this example.

Claims

1. A method for secure wireless WiFi data transmission for wind turbine electrical systems, characterized in that, Includes the following steps: Step S101: Read the SRAM response on the wind turbine nacelle side, synchronously collect the mechanical vector, and obtain the random number at the sending end and the random number at the receiving end respectively, and then generate the session key through the hash key derivation function; The mechanical vector consists of a 128-bit binary vector representing the impeller angular velocity, the tower top yaw angle, and the root mean square of the nacelle vibration. Step S102: For each subcarrier of an orthogonal frequency division multiplexing symbol, the permutation parameters are obtained by discretizing the instantaneous mechanical phase of the rotor, and a permutation function is constructed to rearrange the subcarrier indices accordingly. The substitution parameters consist of the phase amplification factor and the displacement bias; Step S103: First, perform error correction coding on the frame data, and then perform convolutional coding to obtain the overall redundancy rate; Step S104: Generate encrypted random numbers for the current frame's mechanical vector using a hash function, and then perform AES-GCM encryption on the payload using the session key and additional authentication data to obtain a ciphertext frame; Step S105: Within a five-megahertz channel set with a fixed number of channels, calculate the frequency hopping index and ensure that the frequency hopping period is equal to the rotor mechanical cycle, so that the channel is hopped only once per rotor mechanical cycle. Step S106: At the receiving end, the subcarrier order is restored by inverse mapping according to the permutation function, and error correction coding and decoding, AES-GCM tag verification and cyclic redundancy check are performed in sequence to complete one frame data transmission.

2. The method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, The SRAM response is represented by a 256-bit binary vector; the three components of the mechanical vector are quantized into 64-bit, 32-bit, and 32-bit binary vectors by 16-bit, 12-bit, and 10-bit digital converters, respectively; both the transmitting and receiving random numbers are represented by 128-bit binary vectors; and the session key is represented by a 256-bit binary vector.

3. The method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, Multiply the instantaneous mechanical phase of the rotor by the ratio of 255 to 2π, and then use a floor function to obtain a discretized phase value between 0 and 255. Square the three components of the mechanical vector, add them together and take the square root to obtain the second norm of the mechanical vector. Divide the discretized phase value by 31 and take the remainder. Add 1 to the remainder to obtain the phase amplification factor between 1 and 31. Multiply the second norm of the mechanical vector by 10 and use a floor function to calculate the displacement bias by adding the current loop index. The total number of loop indices is the same as the total number of subcarriers.

4. The method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 3, characterized in that, The permutation function is used to calculate the permuted carrier number of each subcarrier, with the cycle index being the k-carrier number. The calculation formula is as follows: Where 1≤k≤63, Indicates the phase amplification factor. This represents the displacement bias at the loop index k, and mod represents the modulo function.

5. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, The error correction coding function has 8 information symbols and a total of 10 symbols. The input to the error correction coding function is 8 consecutive frames of raw payload data, and the output is 10 frames of error correction code, consisting of 8 raw information frames and 2 parity frames. The 10 frames of error correction code are input into convolutional coding. The convolutional code consists of two coding units. The first coding unit and the second coding unit perform an XOR operation on each input bit and the first 6 bits by the coefficients of the first and second convolution polynomials, respectively. Then, each bit of data is concatenated in the cyclic order of the first coding unit and the second coding unit to output 10 frames of convolutionally coded frame data. The coefficients of the first convolution polynomial are represented in octal as 133, and the coefficients of the second convolution polynomial are represented in octal as 171. The code rate of the convolutional code is 1 / 2.

6. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 5, characterized in that, The overall redundancy rate is equal to the ratio between the number of output frames and the number of input frames of the error correction coding function, multiplied by the reciprocal of the code rate of the convolutional code.

7. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, The current frame's mechanical vector is hashed using the BLAKE3 hash function along with the timestamp to obtain a fixed-length 256-bit encrypted random number. The fractional part of the encrypted random number is then extracted, multiplied by 2 to the power of 96, and rounded down to obtain a 96-bit integer random number. This 96-bit integer random number is then used as a counter. The session key is used as the key, and additional authentication data is added as auxiliary authentication information. The payload is then encrypted using AES-GCM to obtain a ciphertext frame containing ciphertext and a 128-bit authentication tag.

8. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 3, characterized in that, First, the root mean square of the nacelle vibration is rounded down and then divided by the fixed number of channels and the remainder is taken to obtain the vibration offset. The fixed number of channels is 16. Then, the discretized phase value is multiplied by a constant 7, added to the vibration offset, and then divided by 16 and the remainder is taken to obtain the frequency hopping index, which is between 0 and 15. Starting from the reference center frequency, the product of the frequency hopping index and the channel spacing of 5MHz is added to obtain the transmission carrier frequency. Finally, the frequency hopping period is equal to the mechanical cycle of the impeller rotation.

9. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, The inverse mapping of the permutation function involves the receiver calculating the permutation parameters using the same parameters as the transmitter, then solving for the multiplicative inverse of the phase amplification coefficient, and finally restoring the subcarrier order for each received subcarrier index using the inverse permutation formula.

10. A method for secure wireless WiFi data transmission for wind turbine electrical systems according to claim 1, characterized in that, The sum of encryption time, subcarrier replacement time, frequency hopping synchronization overhead time, total decoding time, and MAC layer acknowledgment time is calculated and added to the private network transmission time as the alarm response time. If the alarm response time is exceeded, the security execution policy is triggered.

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