A method and system for harmonic suppression of a ship shafting system in cooperation with a battery

Abstract

The application discloses a ship shaft generator system and battery coordination harmonic suppression method and system, and belongs to the technical field of ship power system harmonic suppression; the method comprises the following steps: synchronously collecting three-phase current signals of the shaft generator system and charging and discharging current signals of the battery system, and generating a harmonic characteristic data set; extracting a harmonic phase offset characteristic vector between the shaft generator system and the battery system based on the data set; determining the harmonic phase reversal direction that needs to be compensated by the battery system according to the offset characteristic vector; generating a phase reversal compensation logic matrix based on the harmonic phase reversal direction; generating a dynamic harmonic compensation instruction for driving the battery system according to the matrix; and executing the instruction through a bidirectional converter, so that the battery system outputs an active compensation current opposite to the harmonic phase of the shaft generator system. The system comprises corresponding function modules. The application can track the dynamic drift of the harmonic phase caused by the ship swing in real time, adaptively generate an optimal compensation strategy, and significantly improve the harmonic suppression efficiency and the power grid stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of artificial intelligence, and in particular to a ship shaft generator system and battery collaborative harmonic suppression method and system. BACKGROUND

[0002] In the ship power system, the shaft generator (shaft generator system) is an important power source with energy-saving advantages. However, the shaft generator system inevitably generates current harmonics during operation, which injects into the ship power grid, causing voltage waveform distortion, equipment overheating, relay protection misoperation, communication interference and a series of power quality problems, which seriously threatens the safety and stability of the ship operation. Therefore, effective suppression of shaft generator harmonics is a key technical requirement to improve the quality of the ship power grid.

[0003] The existing harmonic suppression technology, whether it is based on fixed parameters or conventional active compensation strategy (especially passive compensation method relying on preset harmonic model or fixed reference phase), the core control logic usually lacks real-time perception and adaptive adjustment capability for the rapid and large dynamic drift of harmonic phase. When the harmonic phase drift exceeds the phase tracking range or adaptive capacity of the compensation device, there will be a significant phase mismatch between the compensation current and the actual shaft harmonic current. This mismatch not only cannot effectively cancel the target harmonic, but also may produce greater harmonic current or cause system oscillation due to phase superposition, thereby exacerbating the harmonic pollution of the power grid and significantly reducing the efficiency of harmonic suppression and the stability of the system. SUMMARY

[0004] The present application provides a ship shaft generator system and battery collaborative harmonic suppression method and system, which mainly aims to solve the problem of dynamic drift of shaft generator system harmonic phase caused by ship sway, which leads to the failure of traditional passive harmonic suppression method.

[0005] To achieve the above purpose, the present application provides a ship shaft generator system and battery collaborative harmonic suppression method, which comprises:

[0006] Synchronously collecting three-phase current signals output by the shaft generator system and charge-discharge current signals of the battery system to generate a harmonic feature data set;

[0007] Based on the harmonic feature data set, an offset feature vector generated by dynamic coupling between the shaft generator system and the battery system is extracted;

[0008] According to the offset feature vector, the harmonic phase reversal direction that the battery system needs to compensate is determined;

[0009] Based on the harmonic phase reversal direction, a phase reversal compensation logic matrix for canceling the shaft harmonic is generated;

[0010] generate a dynamic harmonic compensation instruction for driving the battery system according to the phase inversion compensation logic matrix;

[0011] execute the dynamic harmonic compensation instruction through a bidirectional converter, so that the battery system outputs an active compensation current opposite to the harmonic phase of the shaft generator system, and realizes harmonic energy offset of the ship power grid.

[0012] To solve the above problems, the application also provides a harmonic suppression system for a ship shaft generator system and a battery, which comprises:

[0013] a current signal acquisition module, configured to synchronously acquire three-phase current signals output by the shaft generator system and charge-discharge current signals of the battery system, and generate a harmonic feature data set;

[0014] an offset feature extraction module, configured to extract an offset feature vector generated by dynamic coupling between the shaft generator system and the battery system based on the harmonic feature data set;

[0015] a compensation direction determination module, configured to determine a harmonic phase inversion compensation direction of the battery system according to the offset feature vector;

[0016] a compensation logic generation module, configured to generate a phase inversion compensation logic matrix for offsetting the shaft generator harmonic based on the harmonic phase inversion compensation direction;

[0017] a driving instruction generation module, configured to generate a dynamic harmonic compensation instruction for driving the battery system according to the phase inversion compensation logic matrix;

[0018] a compensation execution module, configured to execute the dynamic harmonic compensation instruction through a bidirectional converter, so that the battery system outputs an active compensation current opposite to the harmonic phase of the shaft generator system, and realizes harmonic energy offset of the ship power grid.

[0019] Compared with the prior art, the application has the following beneficial effects:

[0020] Firstly, the application synchronously acquires three-phase current signals of the shaft generator system and charge-discharge current signals of the battery system, constructs a harmonic feature data set, and analyzes and extracts a harmonic phase offset feature vector generated by dynamic coupling between the shaft generator system and the battery system due to ship sway, so that the dynamic change rule of the harmonic phase can be captured in real time, and the defect of slow perception of phase drift in the traditional method is overcome.

[0021] Secondly, the application intelligently analyzes the phase shift polarity law based on the extracted offset feature vector, dynamically determines the harmonic phase inversion direction required by the battery system for compensation, and further generates a phase inversion compensation logic matrix that can be adjusted in real time with the phase drift. Finally, through the driving battery system, the active compensation current with accurate phase inversion and amplitude matching is output through the bidirectional converter, which is injected into the ship power grid. The compensation current is opposite in phase to the shaft system harmonic current, directly realizing the dynamic cancellation of harmonic energy, significantly improving the efficiency of harmonic suppression and the adaptability to ship sway conditions. Without presetting fixed parameters, the application can track the phase change in real time, effectively solving the suppression failure problem caused by harmonic phase drift in ship sway conditions, and reducing the ship power grid harmonic distortion rate. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a flowchart of a ship shaft system and battery collaborative harmonic suppression method according to an embodiment of the application.

[0023] Figure 2 FIG. 2 is a functional module diagram of a ship shaft system and battery collaborative harmonic suppression system according to an embodiment of the application.

[0024] The implementation, functional features and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0025] It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application.

[0026] The embodiment of the application provides a ship shaft system and battery collaborative harmonic suppression method. The execution subject of the ship shaft system and battery collaborative harmonic suppression method includes but is not limited to at least one of the electronic devices capable of being configured to execute the method provided by the embodiment of the application, such as a server and a terminal. In other words, the ship shaft system and battery collaborative harmonic suppression method can be executed by software or hardware installed in a terminal device or a server device. The server includes but is not limited to a single server, a server cluster, a cloud server or a cloud server cluster, etc. The server can be a stand-alone server, or a cloud server providing cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content distribution networks, and big data and artificial intelligence platforms, etc. Basic cloud computing services.

[0027] Referring to Figure 1 FIG. 1 is a flowchart of a ship shaft system and battery collaborative harmonic suppression method according to an embodiment of the application. In this embodiment, the ship shaft system and battery collaborative harmonic suppression method includes:

[0028] S1, synchronously collect three-phase current signals output by the shaft power generation system and charge-discharge current signals of the battery system to generate a harmonic feature data set.

[0029] In some embodiments, the step of synchronously collecting three-phase current signals output by the shaft power generation system and charge-discharge current signals of the battery system to generate a harmonic feature data set comprises:

[0030] collecting three-phase current original signals at the generator end of the shaft power generation system through a current sensor;

[0031] collecting charge-discharge current original signals of the direct-current bus of the battery system through a Hall sensor;

[0032] generating a harmonic feature data set according to the three-phase current original signals and the charge-discharge current original signals.

[0033] In the embodiments of the present application, the shaft power generation system is a power supply system composed of a main engine shaft driving a generator in a ship, and the output current thereof contains harmonic components; the three-phase current signals are electrical signals of A, B and C three-phase alternating current output by the generator end of the shaft power generation system.

[0034] In the embodiments of the present application, the battery system is a system for energy storage and charge-discharge operation on a ship, which contains a direct-current bus and a bidirectional converter; the charge-discharge current signals are electrical signals of the current through the direct-current bus during the charge-discharge process of the battery system.

[0035] In the embodiments of the present application, the harmonic feature data set is a data set containing harmonic amplitude, phase and other features extracted after processing the collected three-phase current signals and charge-discharge current signals.

[0036] In the embodiments of the present application, the current sensor is a device capable of detecting the size of three-phase current at the generator end of the shaft power generation system and converting it into a measurable signal; the Hall sensor is a sensor for detecting the charge-discharge current of the direct-current bus of the battery system based on the Hall effect.

[0037] In the embodiments of the present application, the three-phase current original signals are A, B and C three-phase current signals at the generator end of the shaft power generation system collected directly by the current sensor without processing; the charge-discharge current original signals are charge-discharge current signals of the direct-current bus of the battery system collected directly by the Hall sensor without processing.

[0038] In the embodiments of the present application, the step of synchronously collecting three-phase current signals output by the shaft power generation system and charge-discharge current signals of the battery system to generate a harmonic feature data set first needs to complete the collection of two kinds of current signals, and then generate a harmonic feature data set based on the collected original signals, and the specific process is as follows:

[0039] Firstly, the three-phase current original signals of the shaft generator system are collected by the current sensor. The current sensor with the precision level of 0.2 and the measurement range of 0-500 A is installed at the output end of the shaft generator system, and is connected with the A, B and C three-phase lines respectively. The sampling frequency of the sensor is set to 10 kHz to ensure that the high-frequency harmonic components in the current signals can be captured. During the normal navigation of the ship, the current sensor detects the current changes in the three-phase lines in real time, converts the current signals into 4-20 mA standard analog signals, and transmits them to the data acquisition module. For example, when the shaft generator system is in a stable running state, the instantaneous values of the A-phase current original signal, the B-phase current original signal and the C-phase current original signal at a certain moment are 200 A, 195 A and 205 A respectively, which are collected and recorded in real time.

[0040] Then, the charge-discharge current original signals of the battery system DC bus are collected by the Hall sensor. The Hall sensor with the response time less than 1 μs and the measurement range of-200 A to +200 A is connected in series on the DC bus of the battery system. The sampling frequency is also set to 10 kHz, which is consistent with that of the current sensor, to realize the synchronous acquisition of signals. The Hall sensor converts the detected charge-discharge current signals into 0-5 V analog signals, which are transmitted to the same data acquisition module. For example, when the battery system is in a discharging state, the charge-discharge current original signal at a certain moment is-100 A (the negative sign indicates discharging), which is accurately collected and stored at the same time stamp as the three-phase current original signals.

[0041] Finally, the harmonic feature dataset is generated according to the three-phase current original signals and the charge-discharge current original signals. The data acquisition module converts the received analog signals into digital signals, and processes the digital signals by using the fast Fourier transform algorithm. For the three-phase current original signals, the amplitudes and phases of the main harmonics such as 3rd, 5th and 7th harmonics in each phase current are extracted; for the charge-discharge current original signals, the amplitudes and phases of the main harmonics contained therein are also extracted. These extracted harmonic features are sorted in time sequence and phase sequence to form the harmonic feature dataset. For example, after processing, the amplitude of the 3rd harmonic of the A-phase current is 5 A and the phase is 30°, and the amplitude of the 3rd harmonic of the battery system charge-discharge current is 2 A and the phase is 25°, which are orderly included in the dataset.

[0042] In the embodiments of the present application, by synchronously collecting two kinds of current signals and generating a harmonic feature dataset, the dynamic changes of the harmonic phase of the shaft generator system and the response of the battery system under the working conditions such as ship sway can be captured in time, thereby providing data support for solving the problem that the traditional suppression is invalid due to the dynamic drift of the harmonic phase of the ship shaft generator system.

[0043] S2, extract a shift feature vector generated by dynamic coupling between the shaft propulsion system and the battery system based on the harmonic feature data set.

[0044] In some embodiments, the step of extracting the shift feature vector generated by dynamic coupling between the shaft propulsion system and the battery system based on the harmonic feature data set comprises:

[0045] identify a dynamic coupling waveform of the shaft harmonic current and the battery harmonic current under the ship sway working condition based on the harmonic feature data set;

[0046] compare the zero-crossing time difference between the dynamic coupling waveform and the preset reference waveform;

[0047] calculate a real-time phase shift angle of the shaft system harmonic relative to the battery system based on the zero-crossing time difference, and generate a shift feature vector.

[0048] In the embodiments of the present application, the ship sway working condition refers to the running state of the ship in which the ship changes its attitude such as roll and pitch under the action of wind and wave or during turning.

[0049] In the embodiments of the present application, the shaft harmonic current is the current formed by the harmonic component with an integer multiple of the fundamental frequency contained in the output current of the shaft propulsion system; the battery harmonic current is the current containing harmonic component generated in the charging and discharging process of the battery system; and the dynamic coupling waveform is the waveform formed by the superposition of the shaft harmonic current and the battery harmonic current under the ship sway working condition.

[0050] In the embodiments of the present application, the preset reference waveform is a standard waveform formed by the superposition of the shaft harmonic current and the battery harmonic current when the ship is in a stable working condition, which is used as a reference for phase comparison; the zero-crossing time difference is the time difference between the dynamic coupling waveform and the preset reference waveform at the current zero-crossing time; and the real-time phase shift angle is the phase shift angle of the shaft system harmonic relative to the battery system harmonic at a certain time.

[0051] In the embodiments of the present application, the shift feature vector generated by dynamic coupling is a vector used to describe the phase shift between the shaft system harmonic and the battery system harmonic caused by dynamic coupling, which contains information such as the real-time phase shift angle.

[0052] In the embodiments of the present application, the step of extracting the shift feature vector generated by dynamic coupling between the shaft propulsion system and the battery system based on the harmonic feature data set aims to mine the phase shift information caused by the dynamic coupling between the shaft propulsion system and the battery system from the obtained harmonic feature data, which is achieved by identifying the dynamic coupling waveform, calculating the zero-crossing time difference and determining the real-time phase shift angle, and comprises:

[0053] Firstly, based on the harmonic characteristic data set, the dynamic coupling waveform of the shaft harmonic current and the battery harmonic current under the ship sway working condition is identified. This needs to extract the waveform data of the shaft harmonic current and the battery harmonic current at different times from the harmonic characteristic data set, and these data contain the amplitude, phase and frequency information of each harmonic.

[0054] Then, for the ship sway working condition, the shaft harmonic current waveform and the battery harmonic current waveform in the corresponding time period are selected for time-varying waveform superposition effect analysis. For example, 3rd harmonic is selected for analysis, the waveform of the 3rd harmonic current of the shaft at t1 is a sine wave with an amplitude of 5A and a phase of 30°, and the waveform of the 3rd harmonic current of the battery at t1 is a sine wave with an amplitude of 2A and a phase of 25°. The two waveforms are superimposed according to the time axis to obtain the superimposed waveform at t1. By continuously analyzing the superimposed waveforms at multiple times, a dynamic coupling waveform reflecting the phase drift characteristics is extracted. The waveform will show the dynamic offset characteristics of the phase with the change of the shaft speed caused by the ship sway.

[0055] In the embodiment of the present application, the zero-crossing time difference between the dynamic coupling waveform and the preset reference waveform is compared, including: the preset reference waveform is the superimposed waveform of the shaft harmonic current and the battery harmonic current obtained by the same method when the ship sails steadily without obvious sway, and the zero-crossing point position is relatively stable. The identified dynamic coupling waveform and the preset reference waveform are compared in the same time coordinate system to find the zero-crossing points of both (i.e. the time when the current value is zero). For example, the dynamic coupling waveform passes zero at t2, and the preset reference waveform passes zero at t0, so the difference Δt=t2-t0 between the two times is the zero-crossing time difference. When the ship sways, due to the fluctuation of the shaft speed, the zero-crossing point of the dynamic coupling waveform will be advanced or delayed relative to the zero-crossing point of the preset reference waveform. By accurately capturing these times, the zero-crossing time difference at different times can be obtained.

[0056] In the embodiment of the present application, the real-time phase shift angle of the shaft generator system harmonic relative to the battery system is calculated according to the zero-crossing time difference, and a shift feature vector is generated, including: the frequency f of the alternating current is known (the ship power grid is usually 50 Hz), the period T = 1 / f = 0.02 seconds, and the corresponding phase change is 360°. According to the zero-crossing time difference Δt, the real-time phase shift angle can be calculated by the formula "real-time phase shift angle = (Δt / T) x 360°". For example, when the zero-crossing time difference Δt is detected as 0.001 seconds, the real-time phase shift angle can be obtained by substituting the formula as = (0.001 / 0.02) x 360° = 18°. The zero-crossing time differences of multiple consecutive time points are calculated to obtain a series of real-time phase shift angles, which are arranged in time sequence to form a vector, i.e. the shift feature vector. For example, the real-time phase shift angles of three consecutive time points are 18°, 20° and 22° respectively, and the generated shift feature vector is [18°, 20°, 22°].

[0057] In some embodiments, based on the harmonic feature data set, the dynamic coupling waveform of the shaft generator harmonic current and the battery harmonic current under the ship sway working condition is identified, including:

[0058] Based on the shaft generator harmonic current and the battery harmonic current in the harmonic feature data set, time-varying waveform superposition effect analysis is performed on the shaft generator current spectral feature and the battery current spectral feature, and a dynamic coupling waveform representing phase shift characteristics is extracted.

[0059] In the embodiment of the present application, the shaft generator current spectral feature is a collection of frequency, amplitude and phase characteristics of each harmonic in the shaft generator current; and the battery current spectral feature is a collection of frequency, amplitude and phase characteristics of each harmonic in the battery current.

[0060] In the embodiment of the present application, the time-varying waveform superposition effect analysis is an analysis of the effect of the superposition of the shaft generator current waveform and the battery current waveform varying with time, so as to extract the phase shift related features; and the dynamic coupling waveform representing the phase shift characteristics is a superposition waveform that can reflect the phase shift of the shaft generator system harmonic and the battery system harmonic with time.

[0061] In the embodiment of the present application, based on the shaft generator harmonic current and the battery harmonic current in the harmonic feature data set, time-varying waveform superposition effect analysis is performed on the shaft generator current spectral feature and the battery current spectral feature, and a dynamic coupling waveform representing phase shift characteristics is extracted, including:

[0062] First, the shaft generator current spectrum features and the battery current spectrum features are separated from the harmonic feature data set, wherein the shaft generator current spectrum features include the frequency, amplitude and phase of the 3rd, 5th and 7th harmonics, and the battery current spectrum features also include the time-varying data of the corresponding harmonics.

[0063] Then, for each harmonic, the shaft generator harmonic waveform and the battery current harmonic waveform are superimposed according to the time sequence, and the variation law of the amplitude, frequency and phase of the superimposed waveform with time, i.e. the time-varying waveform superposition effect, is analyzed. For example, for the 5th harmonic, the phase of the shaft 5th harmonic is 40° at t3, and the phase of the battery 5th harmonic is 35° at t3, and the phase of the superimposed waveform will be jointly affected by the phase changes of the two. By analyzing the superposition effect, the waveform that can clearly reflect the phase drift between the shaft generator system harmonics and the battery system harmonics, i.e. the dynamic coupling waveform representing the phase drift characteristics, is screened out.

[0064] In the embodiments of the present application, by extracting the offset feature vector, the phase offset of the shaft generator system harmonics relative to the battery system harmonics can be captured in real time, which helps to solve the problem that the traditional suppression method is invalid due to the dynamic phase drift of the shaft generator system harmonics caused by the ship sway.

[0065] S3, determining the harmonic phase reversal direction that the battery system needs to compensate according to the offset feature vector.

[0066] In some embodiments, the determining the harmonic phase reversal direction that the battery system needs to compensate according to the offset feature vector comprises:

[0067] analyzing the polarity distribution law of the phase offset angle in the offset feature vector;

[0068] when the polarity distribution is monotonically increasing in a positive direction, marking that the battery system needs to adopt a positive compensation mode;

[0069] when the polarity distribution is oscillating in a negative direction, triggering the reverse compensation logic of the battery system to generate an instruction.

[0070] In the embodiments of the present application, the harmonic phase reversal direction is the direction opposite to the shaft generator harmonic phase that the battery system needs to maintain when outputting the compensation current to offset the shaft generator system harmonics; and the polarity distribution law is the distribution and change trend of the positive and negative values of the phase offset angle in the offset feature vector in the time sequence.

[0071] In the embodiments of the present application, the monotonically increasing in a positive direction is a state in which the polarity of the phase offset angle is continuously positive and the value is continuously increasing; and the positive compensation mode is a working mode in which the battery system adjusts the phase of the compensation current according to the phase offset that is monotonically increasing in a positive direction.

[0072] In the embodiments of the present application, the negative oscillation is a state in which the polarity of the phase shift angle frequently alternates between positive and negative; and the reverse compensation logic generation instruction is a control instruction triggering the battery system to output a reverse compensation current.

[0073] In some embodiments, the analyzing the polarity distribution rule of the phase shift angle in the offset feature vector comprises:

[0074] The polarity of the phase shift angle in the offset feature vector is converted, and each sampling time angle value is mapped to a discrete positive polarity symbol or a negative polarity symbol to generate an initial polarity symbol sequence;

[0075] The initial polarity symbol sequence is subjected to continuous interval statistics and change trend analysis, and when a monotonous increase in the length of a continuous positive polarity symbol interval is detected, a positive increasing mode is marked, and when a high-frequency alternation of positive polarity symbols and negative polarity symbols is detected, a negative oscillation mode is marked.

[0076] In the embodiments of the present application, the polarity conversion is a process of converting the numerical value of the phase shift angle into a symbol representing positive and negative; and the initial polarity symbol sequence is a sequence composed of continuous symbols obtained by polarity conversion of the phase shift angle.

[0077] In the embodiments of the present application, the continuous interval statistics are statistics on the interval length of the same symbol continuously appearing in the initial polarity symbol sequence; and the change trend analysis is an analysis on the alternation rule of the symbols and the change of the interval length in the initial polarity symbol sequence.

[0078] In the embodiments of the present application, the positive increasing mode is a mode in which the length of the continuous positive polarity symbol interval in the initial polarity symbol sequence is constantly increasing; and the negative oscillation mode is a mode in which the positive and negative symbols appear in high frequency alternation in the initial polarity symbol sequence.

[0079] In some embodiments, when the polarity distribution presents a negative oscillation, the reverse compensation logic generation instruction of the battery system comprises:

[0080] When the mode recognition result of the polarity distribution rule presents a negative oscillation mode, a reverse compensation enable signal of the battery system is generated, and it is marked that the current ship is in a turning or strong wind and wave working condition;

[0081] In response to the reverse compensation enable signal, a reverse compensation instruction frame with a time window identifier is generated as the reverse compensation logic generation instruction of the battery system.

[0082] In the embodiments of the present application, the reverse compensation enable signal is a signal allowing the battery system to start the reverse compensation function; the time window identifier is an identifier marking the valid time range of the reverse compensation instruction; and the reverse compensation instruction frame is an instruction data packet containing reverse compensation parameters and time window information.

[0083] In the embodiments of the present application, determining the harmonic phase inversion direction that the battery system needs to compensate according to the offset feature vector refers to judging the compensation mode that the battery system should adopt by analyzing the polarity change rule of the phase offset angle in the offset feature vector, and then determining the harmonic phase inversion direction. The specific process is as follows:

[0084] First, analyze the polarity distribution rule of the phase offset angle in the offset feature vector. First, perform polarity conversion on each phase offset angle in the offset feature vector. If the angle value is greater than 0, it is mapped to a positive polarity symbol (such as “+”); if the angle value is less than 0, it is mapped to a negative polarity symbol (such as “-”), thereby generating an initial polarity symbol sequence. For example, the offset feature vector is [10°, 15°, -5°, 8°, -3°], and the initial polarity symbol sequence obtained after polarity conversion is [“+”, “+”, “-”, “+”, “-”].

[0085] Next, the sequence is subjected to continuous interval statistics and change trend analysis. The length of the continuous “+” or “-” interval is counted, such as the first continuous “+” interval length of 2, the “-” interval length of 1, the second “+” interval length of 1, and the second “-” interval length of 1 in the above sequence. At the same time, the change trend is analyzed. If the length of the continuous “+” interval increases from 2 to 3, 4, it conforms to the positive increasing mode; if the alternating interval of “+” and “-” is less than 3 sampling periods, it is marked as a negative oscillation mode.

[0086] Then, when the polarity distribution is positively monotonically increasing, mark that the battery system needs to adopt a positive compensation mode. If the initial polarity symbol sequence is [“+”, “+”, “+”, “+”], the length of the continuous positive polarity symbol interval increases from 1 to 4, and it is positively monotonically increasing. At this time, it is judged that the harmonic phase of the shaft generator system is stably positively offset relative to the battery system, and the battery system adopts a positive compensation mode. In this mode, the phase of the compensation current is adjusted synchronously with the positive offset of the shaft generator harmonic phase, ensuring that it always maintains an opposite phase with the shaft generator harmonic. For example, the shaft generator harmonic phase is 30°, the phase offset angle is 10°, and the battery system compensation current phase is set to 30°+180°-10°=200° to achieve phase inversion.

[0087] Finally, when the polarity distribution is negatively oscillating, trigger the reverse compensation logic generation instruction of the battery system. If the initial polarity symbol sequence is [“+”, “-”, “+”, “-”, “+”], the positive and negative symbol alternating interval is 1 sampling period, and it is negatively oscillating. At this time, it is indicated that the ship may be in a severe rolling working condition, and the shaft generator harmonic phase offset is unstable, so the reverse compensation logic generation instruction needs to be triggered.

[0088] In the embodiment of the present application, the polarity distribution rule of the phase shift angle in the offset feature vector is analyzed, including: determining the analysis window length in combination with the sampling frequency (such as 10 kHz) of the ship power grid, and usually taking 100 sampling points as an analysis window. The initial polarity symbol sequence in each window is counted, and the proportion of positive polarity symbols and the maximum length of continuous interval are calculated. If the lengths of the positive polarity continuous intervals of three consecutive windows are 5, 8 and 12 respectively, it is determined as a positive increasing mode; if the number of positive and negative symbol alternations in the same window exceeds 20 times, it is determined as a negative oscillation mode.

[0089] In the embodiment of the present application, when the polarity distribution is in a negative oscillation mode, the reverse compensation logic of the battery system generates an instruction, including: when the mode recognition result is a negative oscillation mode, the control system generates a reverse compensation enable signal, and at the same time, through the feedback information of the ship attitude sensor (such as a gyroscope), it is marked that the current ship is in a turning or strong wind and wave working condition. In response to the enable signal, the system generates a reverse compensation instruction frame with a time window identifier, and the time window identifier is usually set to 500 ms, that is, the instruction is valid within 500 ms. The instruction frame contains the amplitude adjustment coefficient (such as 1.2 times the reference value) of the compensation current and the phase correction parameter, to ensure that the battery system can quickly output the reverse compensation current in a short time. For example, the shaft harmonic phase is 45°, and at this time, the compensation current phase is set to 45°+180°+5°=230° (the additional 5° is a correction value), to offset the phase shift of the high-frequency change.

[0090] In the embodiment of the present application, by accurately identifying the polarity distribution rule of the phase shift, the battery system can dynamically adjust the compensation direction, solve the problem that the traditional passive compensation cannot track the dynamic drift of the shaft harmonic phase, and ensure that the compensation current is always opposite to the shaft harmonic, thereby improving the harmonic suppression effect.

[0091] S4, generating a phase inversion compensation logic matrix for offsetting the shaft harmonic based on the harmonic phase inversion direction.

[0092] In some embodiments, the generating a phase inversion compensation logic matrix for offsetting the shaft harmonic based on the harmonic phase inversion direction includes:

[0093] The harmonic phase inversion direction is mapped to a switching time sequence rule of the bidirectional converter, the duty cycle parameter of the switching time sequence rule is adjusted according to the real-time phase shift angle, and a phase inversion compensation logic matrix containing the switching time sequence rule and the duty cycle parameter is output.

[0094] In the embodiment of the present application, the harmonic phase inversion direction is the direction of the compensation current output by the battery system, which is required to keep opposite to the phase of the shaft generator harmonic to offset the shaft generator harmonic; the phase inversion compensation logic matrix is a matrix for controlling the switching state of the bidirectional converter to realize harmonic phase inversion compensation, which contains switching timing rules and duty cycle parameters.

[0095] In the embodiment of the present application, the bidirectional converter is a power electronic device connecting the battery system and the ship power grid, which can realize bidirectional conversion of electric energy, and the current output is controlled by the on-off of the switching device; the switching timing rules are rules for regulating the on-off sequence and time interval of the switching device in the bidirectional converter.

[0096] In the embodiment of the present application, the real-time phase offset angle is the phase deviation angle of the shaft generator system harmonic relative to the battery system harmonic at the current time; the duty cycle parameter is the ratio of the on-time of the switching device of the bidirectional converter to the total time in a period, which is used to adjust the amplitude of the output current.

[0097] In the embodiment of the present application, based on the harmonic phase inversion direction, the phase inversion compensation logic matrix for offsetting the shaft generator harmonic is to convert the determined harmonic phase inversion direction into specific logic parameters that can control the action of the bidirectional converter, and finally form the phase inversion compensation logic matrix by mapping the switching timing rules and adjusting the duty cycle parameters.

[0098] In the embodiment of the present application, mapping the harmonic phase inversion direction to the switching timing rules of the bidirectional converter includes: the harmonic phase inversion direction determines the phase relationship between the compensation current and the shaft generator harmonic current, which needs to be realized through the switching action of the bidirectional converter. The bidirectional converter contains 6 IGBT switching devices (corresponding to three-phase bridge arms), and the combination of their switching states determines the phase of the output current.

[0099] For example, when the harmonic phase inversion direction requires the phase of the compensation current to be 180° plus the phase of the shaft generator harmonic, for the A-phase current, if the shaft generator harmonic current is in the positive half cycle at a certain time, the compensation current needs to be in the negative half cycle, at this time, the corresponding A-phase upper bridge arm switching device is turned off and the lower bridge arm switching device is turned on, and the on-off sequence is arranged in time sequence, that is, the switching timing rules of the A-phase are formed; similarly, the switching timing rules of the B-phase and the C-phase are generated, and the overall switching timing rules of the bidirectional converter are obtained after combination.

[0100] In the embodiments of the present application, the duty cycle parameter of the switch timing rule is adjusted according to the real-time phase shift angle, which reflects the dynamic change of the shaft harmonic phase, and needs to be adjusted to ensure that the compensation current amplitude matches the shaft harmonic current amplitude to achieve effective cancellation. The initial reference value of the duty cycle parameter is set according to the rated amplitude of the shaft harmonic current, for example, when the reference duty cycle is 0.5, the corresponding compensation current amplitude is 5A. When the real-time phase shift angle is 10° (assuming that the phase shift angle is positively correlated with the harmonic amplitude), the adjusted duty cycle is calculated according to the formula "adjusted duty cycle = reference duty cycle × (1 + real-time phase shift angle / maximum shift angle)", wherein the maximum shift angle is 30°, and then the adjusted duty cycle = 0.5 × (1 + 10° / 30°) ≈ 0.67, at this time the compensation current amplitude is increased accordingly to adapt to the change of the shaft harmonic current amplitude.

[0101] In the embodiments of the present application, outputting the phase inversion compensation logic matrix containing the switch timing rule and the duty cycle parameter, comprises: integrating the generated switch timing rule and the adjusted duty cycle parameter into a matrix form according to a certain format. The rows of the matrix correspond to the switching devices of the three-phase bridge arm, and the columns correspond to the sampling points in the time sequence, and each element contains the conduction and off state of the switching device at that time (represented by "1" for conduction and "0" for off) and the corresponding duty cycle value.

[0102] For example, the element of the A-phase upper arm at t1 in the matrix is "0 (off), 0.67", which means that at this time the switching device is off and the corresponding duty cycle is 0.67. In this way, the switch timing rule and the duty cycle parameter are systematically organized to form a phase inversion compensation logic matrix, providing complete control logic for driving the bidirectional converter.

[0103] In the embodiments of the present application, by generating the phase inversion compensation logic matrix, the abstract harmonic phase inversion direction is converted into specific control parameters executable by the bidirectional converter, ensuring that the compensation current can accurately track the dynamic drift of the shaft harmonic phase, solving the problem of fixed control logic in traditional compensation methods that cannot adapt to phase changes, and improving the accuracy of harmonic suppression.

[0104] S5, generating a dynamic harmonic compensation instruction for driving the battery system according to the phase inversion compensation logic matrix.

[0105] In some embodiments, the generating a dynamic harmonic compensation instruction for driving the battery system according to the phase inversion compensation logic matrix comprises:

[0106] converting the phase inversion compensation logic matrix into a pulse code sequence recognizable by the battery system;

[0107] The current amplitude of the pulse coding sequence is dynamically scaled according to the real-time state of charge of the battery system, and a driving instruction queue with a time stamp is generated as a dynamic harmonic compensation instruction of the battery system.

[0108] In the embodiments of the present application, the dynamic harmonic compensation instruction is an instruction for driving the battery system to output a specific compensation current to offset the shaft harmonic, including current amplitude, phase and time information; the pulse coding sequence is a binary coding sequence converted from the switch timing sequence and duty cycle parameters in the phase inversion compensation logic matrix, which can be recognized by the control module of the battery system.

[0109] In the embodiments of the present application, the real-time state of charge is the proportion of the current remaining capacity to the total capacity of the battery system, used to reflect the available energy state of the battery; the current amplitude is the size of the compensation current, which needs to be dynamically adjusted according to the amplitude of the shaft harmonic; the dynamic scaling is the process of adjusting the current amplitude according to the real-time state of charge of the battery, to ensure that the compensation current is within the safe output range of the battery; the time stamp is a time identifier added to the driving instruction, used to ensure that the instruction is synchronized with the frequency of the ship power grid; the driving instruction queue is a series of driving instructions arranged in chronological order, used to realize continuous dynamic harmonic compensation.

[0110] In the embodiments of the present application, the dynamic harmonic compensation instruction for driving the battery system is generated according to the phase inversion compensation logic matrix, which is converted from the phase inversion compensation logic matrix into an instruction that can be directly executed by the battery system, through encoding conversion and amplitude adjustment, to form continuous driving instructions.

[0111] In the embodiments of the present application, the phase inversion compensation logic matrix is converted into a pulse coding sequence recognizable by the battery system, including: the phase inversion compensation logic matrix contains switch timing rules and duty cycle parameters, which need to be converted into a binary pulse sequence through an encoding algorithm.

[0112] For example, the switch state of the A-phase upper arm in the matrix is "on-off-on", the corresponding time interval is 1ms-2ms-1ms, and the duty cycle is 0.67, which can be converted into the pulse coding sequence "101" (1 represents on, 0 represents off), where the width of each pulse corresponds to the time interval, and the density of the pulse reflects the duty cycle. During the conversion process, it is necessary to ensure that the format of the coding sequence matches the interface protocol of the battery system control module, such as the frame structure specified by the RS485 communication protocol, which includes start bit, data bit and check bit.

[0113] In the embodiments of the present application, the current amplitude of the pulse code sequence is dynamically scaled according to the real-time state of charge of the battery system, including: the real-time state of charge is collected by the battery management system, for example, the current state of charge is 80%. The maximum compensation current amplitude of the battery at full state of charge (100%) is set to 10A, and when the state of charge is lower than 20%, the maximum amplitude is limited to 5A to avoid over-discharge. A linear scaling formula "adjusted current amplitude = reference current amplitude x real-time state of charge" is used, if the reference current amplitude is 8A (determined according to the shaft harmonic amplitude), then the adjusted current amplitude = 8A x 80% = 6.4A. The dynamic adjustment of the current amplitude is realized by modifying the field of the corresponding amplitude in the pulse code sequence.

[0114] In the embodiments of the present application, the drive instruction queue with timestamp markers is generated as the dynamic harmonic compensation instruction of the battery system, including: a 32-bit binary value is assigned to the timestamp marker, accurate to the millisecond level, for example, the current timestamp is "1694567890123". The converted pulse code sequence, the adjusted current amplitude and the timestamp are combined in order to form an instruction frame, each instruction frame corresponds to a compensation task of one sampling period (such as 20ms). A plurality of continuous instruction frames are sorted by timestamp to form a drive instruction queue. For example, the queue contains the instruction frame corresponding to the timestamp "1694567890123" of 6.4A, and the instruction frame corresponding to the timestamp "1694567890143" of 6.3A (the state of charge decreases slightly), to ensure that the battery system outputs compensation current in time sequence, and matches the dynamic change of the shaft harmonic in real time.

[0115] In the embodiments of the present application, by converting the logic matrix into executable instructions and dynamically adjusting the current amplitude, it is ensured that the compensation current output by the battery system can accurately match the phase and amplitude of the shaft harmonic, and can also adapt to the change of the state of charge itself, solving the poor adaptability problem caused by the fixation of traditional compensation instructions, and improving the stability of harmonic suppression.

[0116] S6, execute the dynamic harmonic compensation instruction through the bidirectional converter, so that the battery system outputs active compensation current opposite to the harmonic phase of the shaft system, to realize harmonic energy offset of the ship power grid.

[0117] In some embodiments, the dynamic harmonic compensation instruction is executed through the bidirectional converter, so that the battery system outputs active compensation current opposite to the harmonic phase of the shaft system, to realize harmonic energy offset of the ship power grid.

[0118] The pulse code sequence and the timestamp marker in the dynamic harmonic compensation instruction are parsed;

[0119] generating a power semiconductor drive signal synchronized with the ship power grid frequency based on the pulse code sequence and the timestamp mark;

[0120] outputting a compensation current waveform opposite in phase to the shaft propulsion system harmonic phase to the ship power grid through the bidirectional converter to achieve harmonic energy cancellation of the ship power grid.

[0121] In the embodiments of the present application, the active compensation current is the current output by the battery system under the driving of the dynamic harmonic compensation instruction, which is opposite in phase to the shaft propulsion system harmonic phase and used for canceling harmonic energy; the power semiconductor drive signal is an electrical signal used for controlling the turn-on and turn-off of power semiconductor devices (such as IGBT) in the bidirectional converter, and the frequency thereof is synchronized with the ship power grid frequency.

[0122] In the embodiments of the present application, the compensation current waveform is the form of the active compensation current changing with time, which needs to be opposite in phase and matched in amplitude to the shaft propulsion system harmonic waveform; the harmonic energy cancellation is the process that the active compensation current and the shaft propulsion system harmonic current are superimposed due to the opposite phase, and the harmonic energy is reduced, so as to reduce the harmonic distortion of the ship power grid.

[0123] In the embodiments of the present application, the step of executing the dynamic harmonic compensation instruction through the bidirectional converter to make the battery system output the active compensation current opposite in phase to the shaft propulsion system harmonic phase to achieve the harmonic energy cancellation of the ship power grid is the execution link of the whole harmonic suppression process, and the harmonic energy cancellation is finally completed through the analysis instruction, the generation of the drive signal and the output of the compensation current.

[0124] In the embodiments of the present application, the analysis of the pulse code sequence and the timestamp mark in the dynamic harmonic compensation instruction includes that after the control unit of the bidirectional converter receives the dynamic harmonic compensation instruction, the pulse code sequence and the timestamp mark are extracted through a decoding algorithm.

[0125] For example, the pulse code sequence in the instruction is “10101”, which corresponds to the “turn-on-turn-off-turn-on-turn-off-turn-on” timing of the switching device; the timestamp mark is “1694567890143”, which indicates that the instruction needs to take effect at this time. In the analysis process, the control unit will check the integrity of the code sequence (such as through CRC check) to ensure that the instruction is not disturbed, and at the same time, the timestamp mark is synchronized with the local clock to ensure the time accuracy of the instruction execution.

[0126] In the embodiments of the present application, the power semiconductor drive signal synchronized with the ship power grid frequency is generated based on the pulse code sequence and the timestamp mark, which includes that the ship power grid frequency is 50 Hz (period 20 ms), and the control unit decomposes the switching action into each power grid period according to the timing information in the pulse code sequence.

[0127] For example, the pulse coding sequence requires the action of "turning on for 5 ms - turning off for 5 ms" to be completed within 10 ms, and the control unit generates a square wave driving signal with a duty cycle of 50% accordingly. At the same time, the starting phase of the driving signal is adjusted in combination with the time stamp mark to ensure that the driving signal is synchronized with the zero-crossing point of the grid voltage waveform (e.g., the first on period is started at the zero-crossing of the grid voltage), avoiding additional harmonics generated by switching actions.

[0128] In the embodiments of the present application, through the bidirectional converter, the compensation current waveform opposite in phase to the shaft propulsion system harmonic phase is output to the ship power grid according to the power semiconductor driving signal, realizing the cancellation of the harmonic energy of the ship power grid, including: the IGBT device in the bidirectional converter is sequentially turned on and turned off under the control of the power semiconductor driving signal, converting the direct current of the battery system into alternating current. For example, when the shaft propulsion system A-phase 3rd harmonic current is a sine wave (phase 30°, amplitude 5A), the compensation current waveform output by the bidirectional converter is a sine wave with a phase of 210° (30°+180°) and an amplitude of 5A, and the two are opposite in phase. The compensation current is injected into the ship power grid after filtering out high-frequency noise by a filter circuit (such as an LC filter), and is superimposed with the shaft propulsion system harmonic current. Due to the opposite phases, the amplitude of the superimposed harmonic current is significantly reduced, realizing the cancellation of the harmonic energy. For example, the amplitude of the superimposed A-phase 3rd harmonic current is reduced from 5A to less than 1A, and the harmonic distortion rate of the ship power grid is effectively controlled.

[0129] In the embodiments of the present application, through the precise execution of the bidirectional converter, the active compensation current output by the battery system can track the dynamic phase drift of the shaft propulsion system harmonic in real time, solving the suppression failure problem caused by the inability of traditional passive compensation to adapt to phase changes, effectively reducing the harmonic content of the ship power grid, and improving the stability of the power grid operation.

[0130] As Figure 2 shown, is a functional module diagram of a ship shaft propulsion system and battery collaborative harmonic suppression system provided by an embodiment of the present application.

[0131] The ship shaft propulsion system and battery collaborative harmonic suppression system 100 described in the present application can be installed in an electronic device. According to the functions implemented, the ship shaft propulsion system and battery collaborative harmonic suppression system 100 can include a current signal acquisition module 101, an offset feature extraction module 102, a compensation direction determination module 103, a compensation logic generation module 104, a driving instruction generation module 105, and a compensation execution module 106. The modules described in the present application can also be referred to as units, which refer to a series of computer program segments that can be executed by an electronic device processor and can complete a fixed function, and are stored in the memory of the electronic device.

[0132] In the embodiments, the functions of each module / unit are as follows:

[0133] The current signal acquisition module 101 is configured to synchronously acquire three-phase current signals output by the shaft generator system and charge-discharge current signals of the battery system, and generate a harmonic feature data set;

[0134] The offset feature extraction module 102 is configured to extract an offset feature vector generated by dynamic coupling between the shaft generator system and the battery system based on the harmonic feature data set;

[0135] The compensation direction determination module 103 is configured to determine a harmonic phase inversion direction that needs to be compensated by the battery system according to the offset feature vector;

[0136] The compensation logic generation module 104 is configured to generate a phase inversion compensation logic matrix for offsetting the shaft generator harmonic based on the harmonic phase inversion direction;

[0137] The drive instruction generation module 105 is configured to generate a dynamic harmonic compensation instruction for driving the battery system according to the phase inversion compensation logic matrix;

[0138] The compensation execution module 106 is configured to execute the dynamic harmonic compensation instruction through a bidirectional converter, so that the battery system outputs an active compensation current opposite to the harmonic phase of the shaft generator system, and realizes harmonic energy offset of the ship power grid.

[0139] In several embodiments provided in the present application, it should be understood that the disclosed method and system can be implemented in other ways. For example, the system embodiments described above are only illustrative, for example, the division of the modules is only a logical function division, and another division mode can be used in actual implementation.

[0140] The modules described as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical units, that is, they can be located in one place or distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0141] In addition, each functional module in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of hardware plus software functional modules.

[0142] It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

[0143] The embodiments of the present application can acquire and process related data based on artificial intelligence technology. The artificial intelligence is a theory, method, technology and application system for simulating, extending and expanding human intelligence by using a digital computer or a machine controlled by a digital computer, perceiving an environment, acquiring knowledge and using the knowledge to obtain optimal results.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A harmonic suppression method for a ship's shaft generator system and battery working in tandem, characterized in that, The method includes: The three-phase current signal output by the shaft generator system and the charging and discharging current signal of the battery system are acquired simultaneously to generate a harmonic characteristic dataset. Based on the harmonic feature dataset, the offset feature vector generated by the dynamic coupling between the shaft power system and the battery system is extracted; Determining the harmonic phase reversal direction that the battery system needs to compensate for based on the offset feature vector includes: Analyzing the polarity distribution of the phase offset angle in the offset feature vector includes: The phase offset angle in the offset feature vector is polarity converted, and the angle value at each sampling time is mapped to a discrete positive or negative polarity sign to generate an initial polarity sign sequence. The initial polarity symbol sequence is subjected to continuous interval statistics and trend analysis. When the length of the continuous positive polarity symbol interval is detected to increase monotonically, it is marked as a positive increasing mode. When positive polarity symbols and negative polarity symbols are detected to alternate at high frequency, it is marked as a negative oscillation mode. When the polarity distribution shows a positive monotonically increasing trend, the battery system is indicated to require a positive compensation mode. When the polarity distribution exhibits negative oscillation, the reverse compensation logic of the battery system is triggered to generate instructions, including: When the pattern recognition result of the polarity distribution law is a negative oscillation mode, the reverse compensation enable signal of the battery system is generated, and the current ship is marked as being in a turning or strong wind and wave condition. In response to the reverse compensation enable signal, a reverse compensation instruction frame with a time window identifier is generated as the reverse compensation logic generation instruction of the battery system. Based on the harmonic phase reversal direction, a phase reversal compensation logic matrix for canceling axial harmonics is generated, including: The harmonic phase reversal direction is mapped to the switching timing rule of the bidirectional converter. The duty cycle parameter of the switching timing rule is adjusted according to the real-time phase offset angle. The output is a phase reversal compensation logic matrix containing the switching timing rule and the duty cycle parameter. The dynamic harmonic compensation command for driving the battery system is generated based on the phase reversal compensation logic matrix. The dynamic harmonic compensation command is executed by a bidirectional converter, causing the battery system to output an active compensation current that is opposite in phase to the harmonics of the shaft generator system, thereby achieving harmonic energy cancellation of the ship's power grid.

2. The harmonic suppression method for ship shaft generator system and battery coordination as described in claim 1, characterized in that, The synchronous acquisition of the three-phase current signal output by the shaft generator system and the charging and discharging current signal of the battery system generates a harmonic characteristic dataset, including: The raw three-phase current signal at the generator terminal of the shaft generator system is acquired by a current sensor; The raw charging and discharging current signal of the DC bus of the battery system is acquired using a Hall sensor. A harmonic feature dataset is generated based on the original three-phase current signal and the original charging / discharging current signal.

3. The harmonic suppression method for ship shaft generator system and battery coordination as described in claim 1, characterized in that, The step of extracting the offset feature vector generated by the dynamic coupling between the shaft-driven system and the battery system based on the harmonic feature dataset includes: Based on the harmonic feature dataset, the dynamic coupling waveform of shaft-generated harmonic current and battery harmonic current under ship swaying conditions is identified. Compare the zero-crossing time difference between the dynamically coupled waveform and the preset reference waveform; The real-time phase offset angle of the shaft generator system harmonics relative to the battery system is calculated based on the zero-crossing time difference, and an offset feature vector is generated.

4. The harmonic suppression method for ship shaft generator system and battery coordination as described in claim 1, characterized in that, The step of generating dynamic harmonic compensation instructions to drive the battery system based on the phase reversal compensation logic matrix includes: The phase reversal compensation logic matrix is ​​converted into a pulse code sequence that the battery system can recognize; The current amplitude of the pulse-coded sequence is dynamically scaled according to the real-time state of charge of the battery system to generate a drive instruction queue with timestamps as the dynamic harmonic compensation instruction of the battery system.

5. The harmonic suppression method for ship shaft generator system and battery coordination as described in claim 1, characterized in that, The dynamic harmonic compensation command is executed via a bidirectional converter, causing the battery system to output an active compensation current with a harmonic phase opposite to that of the shaft generator system, thereby achieving harmonic energy cancellation in the ship's electrical grid. Analyze the pulse code sequence and timestamp in the dynamic harmonic compensation command; A power semiconductor drive signal synchronized with the ship's electrical grid frequency is generated based on the pulse-coded sequence and the timestamp mark. By using a bidirectional converter, a compensation current waveform with a phase opposite to the harmonics of the shaft generator system is output to the ship's electrical grid based on the power semiconductor drive signal, thereby achieving harmonic energy cancellation of the ship's electrical grid.

6. A harmonic suppression system for a ship's shaft-mounted generator system and battery in coordination, used to implement the harmonic suppression method for a ship's shaft-mounted generator system and battery in coordination as described in any one of claims 1-5, characterized in that, The system includes: The current signal acquisition module is used to synchronously acquire the three-phase current signal output by the shaft generator system and the charging and discharging current signal of the battery system to generate a harmonic characteristic dataset. The offset feature extraction module is used to extract the offset feature vector generated by the dynamic coupling between the shaft power system and the battery system based on the harmonic feature dataset. The compensation direction determination module is used to determine the harmonic phase reversal direction that the battery system needs to compensate for based on the offset feature vector; The compensation logic generation module is used to generate a phase reversal compensation logic matrix for canceling axial harmonics based on the harmonic phase reversal direction. A drive instruction generation module is used to generate dynamic harmonic compensation instructions for driving the battery system based on the phase reversal compensation logic matrix. The compensation execution module is used to execute the dynamic harmonic compensation command through the bidirectional converter, so that the battery system outputs an active compensation current with the harmonic phase opposite to that of the shaft generator system, thereby realizing the cancellation of harmonic energy in the ship's power grid.

Images