An implementation method and system of precise phase-locked starting of a gas engine static frequency converter

Abstract

The application discloses an implementation method of precise phase locking of gas turbine static frequency converter starting, determines that a rotor is in four different frequency bands of static, super-low frequency turning gear, low frequency rotation or high frequency rotation according to the change of rotor position, and measures the rotor position of each frequency band by using different rotor position detection methods according to the different frequency bands of the rotor. The application also discloses an implementation system of precise phase locking of gas turbine static frequency converter starting. The frequency bands of the rotor are divided into the four frequency bands of static, super-low frequency turning gear, low frequency rotation or high frequency rotation. Since the power characteristics of the frequency bands are quite different, the application adopts different rotor position detection methods, can eliminate the different defects of the power of different frequency bands in a targeted manner, and thus precisely measures the rotor position of each frequency band and realizes the precise phase locking in the starting process of the gas turbine static frequency converter.

Description

Technical Field

[0001] This invention relates to the field of current sampling technology, specifically to a method and system for achieving precise phase-locked loop during the start-up of a gas turbine static frequency converter. Background Technology

[0002] Gas turbines have seen rapid development in recent years due to their high thermal efficiency, clean and environmentally friendly operation, and fast load ramp-up, making them an important direction for future peak-shaving heating or main power unit development. Because of the significant technological advantages of static frequency converters (SFCs), large gas turbines often employ SFC starting.

[0003] A static frequency converter (SFD) is a current-source frequency converter. Gas turbine startup often uses 12-6 pulse structure SFDs, such as... Figure 1 As shown, the SFC (Stable Frequency Converter) consists of bridge 1, bridge 2, smoothing reactor, motor bridge, SFC control and protection system, generator / grid side voltage transformers, generator / grid side current transformers, and switching switches. The power devices in bridge 1, bridge 2, and the motor bridge utilize thyristors. The rotor position is primarily obtained through terminal electrical quantities. The static frequency converter operates in two stages during synchronous motor startup: a low-speed stage and a high-speed stage. In the low-speed stage, intermittent commutation is used to drive the rotor to 10% of its rated speed, while in the high-speed stage, natural commutation is used to drive the rotor to 105% of its rated speed. However, the static frequency converter startup process involves multiple frequency bands with significant differences in electrical characteristics, and the unit speed changes rapidly. Traditional constant-frequency phase-locked loop (SCLL) algorithms cannot meet the requirements.

[0004] Utility model patent application CN204290788U discloses a static inverter starting control device. This application generates control signals according to a certain control strategy based on the rotor's actual position and speed, controlling the frequency, amplitude, and phase of the inverter's output three-phase current (voltage) to achieve motor speed tracking of rotor speed, while reducing the requirements on components such as thyristors and filters. However, it cannot solve the aforementioned problems. Summary of the Invention

[0005] The technical problem to be solved by this invention is to solve the problem that existing static frequency converters cannot accurately lock phase when the rotor is in different frequency bands during startup.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A method for achieving precise phase-locked starting of a gas turbine static frequency converter is proposed. Based on the change in rotor position, the rotor is determined to be in one of four different frequency bands: stationary, ultra-low frequency turning, low frequency rotation, or high frequency rotation. Different rotor position detection methods are used to measure the rotor position in each frequency band according to the different frequency bands in which the rotor is located.

[0008] Advantages: This invention divides the rotor frequency band into four bands: stationary, ultra-low frequency turning, low frequency rotation, and high frequency rotation. Since the electrical characteristics of these frequency bands are quite different, this invention uses different rotor position detection methods to specifically eliminate the different shortcomings of electrical characteristics in different frequency bands, thereby accurately measuring the rotor position of each frequency band and achieving precise phase locking during the start-up process of the gas turbine stationary inverter.

[0009] Preferably, when the rotor is stationary, the following steps are included:

[0010] S1. The motor stator bridge voltage is transformed by Park, then processed by a second-order bandpass filter, and then amplitude and phase compensation is performed to obtain the unit potential. The unit potential is integrated within the pulse width time, and then the initial rotor position is calculated by arctangent calculation.

[0011] Preferably, when the rotor is in ultra-low frequency turning, the following steps are included:

[0012] S2. The motor stator bridge voltage is transformed by Park, then processed by a second-order bandpass filter, and then amplitude and phase compensation is performed to obtain the unit electromotive force. Finally, the rotor position is calculated by arctangent calculation.

[0013] Preferably, when the rotor is rotating at a low frequency, the following steps are included:

[0014] S3. Perform Park transformation on the bridge voltage of the motor stator, obtain the terminal potential through the first machine side voltage equation, process it through a second-order bandpass filter, perform amplitude and phase compensation to obtain the unit flux linkage, and then perform arctangent calculation to obtain the rotor position at this time.

[0015] The calculation formula for the voltage equation on the first machine side is as follows:

[0016]

[0017] In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current.

[0018] Preferably, when the rotor is rotating at a high frequency, the following steps are included:

[0019] S4. Perform Park transformation on the bridge voltage of the motor stator, obtain the terminal potential through the second side voltage equation, smooth the obtained curve, apply a second-order bandpass filter, and then perform amplitude and phase compensation to obtain the unit flux linkage; finally, calculate the rotor position using arctangent calculation.

[0020] The calculation formula for the second machine-side voltage equation is as follows:

[0021]

[0022] In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current.

[0023] Preferably, it also includes a phase-locked loop anomaly detection process:

[0024] S5. Based on the rotor position measured in steps S1-S4, determine the theoretically conducting thyristor THY. SEL_X ;

[0025] S6. Based on the bridge current, determine the actual conducting thyristor THY. X ;

[0026] S7, if the THY in step S5 SEL_X With step S6, THY X If they are different, and the changes in rotor position are considered, a phase-locked loop anomaly can be determined.

[0027] This invention also discloses a system for achieving precise phase-locked loop during the start-up of a gas turbine static frequency converter, comprising:

[0028] Judgment module: used to determine whether the rotor is in one of four different frequency bands: stationary, ultra-low frequency turning, low frequency rotation, or high frequency rotation, based on changes in rotor position;

[0029] Processing module: Used to measure the rotor position of each frequency band by using different rotor position detection methods according to the different frequency bands in which the rotor is located.

[0030] Preferably, the processing module includes a static processing unit, which includes:

[0031] Static conversion unit; used to perform Park conversion on the bridge voltage of the motor stator.

[0032] The static filtering unit processes the transformed bridge voltage through a second-order bandpass filter.

[0033] The static compensation unit is used to perform amplitude and phase compensation to obtain the unit's electromotive force.

[0034] The static integrator unit is used to integrate the potential of the above-mentioned units separately within the pulse width time.

[0035] The static arctangent unit is used to perform arctangent calculations on the integrated unit electromotive force to obtain the initial rotor position.

[0036] Preferably, the processing module includes an ultra-low frequency processing unit, which includes:

[0037] The ultra-low frequency converter unit is used to perform Park conversion on the bridge voltage of the motor stator.

[0038] The ultra-low frequency filtering unit processes the transformed bridge voltage through a second-order bandpass filter.

[0039] The ultra-low frequency compensation unit is used to perform amplitude and phase compensation to obtain the unit's electromotive force;

[0040] The ultra-low frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

[0041] Preferably, the processing module includes a low-frequency processing unit, which includes:

[0042] The low-frequency conversion unit is used to perform Park conversion on the bridge voltage of the motor stator.

[0043] The first machine-side unit is used to obtain the terminal potential through the first machine-side voltage equation;

[0044] The low-frequency filtering unit is used to process the terminal potential through a second-order bandpass filter.

[0045] The low-frequency compensation unit is used to compensate the amplitude and phase of the generator terminal potential to obtain the generator flux linkage;

[0046] The low-frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

[0047] Compared with the prior art, the beneficial effects of the present invention are:

[0048] (1) The present invention divides the frequency band of the rotor into four frequency bands: stationary, ultra-low frequency turning, low frequency rotation, or high frequency rotation. Since the electrical characteristics of these frequency bands are quite different, the present invention adopts different rotor position detection methods, which can specifically eliminate the different defects of electrical quantities in different frequency bands, thereby accurately measuring the rotor position of each frequency band and realizing accurate phase locking during the start-up process of the gas turbine stationary frequency converter.

[0049] (2) The present invention uses a second-order bandpass filter to more effectively filter out low-frequency DC offset components and high-frequency harmonic components.

[0050] (3) When the rotor is rotating at high frequency, the present invention uses the least squares method to smooth the terminal potential, bridge the commutation voltage gap, and improve the accuracy of measuring the rotor position. Attached Figure Description

[0051] Figure 1 A schematic diagram for starting a synchronous motor using an existing gas turbine static inverter.

[0052] Figure 2 This is a schematic diagram illustrating the rotor position detection principle of Embodiment 1 of the present invention;

[0053] Figure 3 This is a waveform diagram of the magnetic flux linkage when the rotor is stationary according to Embodiment 1 of the present invention;

[0054] Figure 4 This is a waveform diagram showing the error between the initial position and the actual position of the rotor when the rotor is stationary, according to Embodiment 1 of the present invention.

[0055] Figure 5 This is a waveform diagram of the magnetic flux linkage of the rotor during ultra-low frequency turning of the rotor according to Embodiment 1 of the present invention;

[0056] Figure 6 This is a waveform diagram of the magnetic flux linkage of the rotor during low-frequency rotation, according to Embodiment 1 of the present invention.

[0057] Figure 7 This is a waveform diagram of the generator potential during high-frequency rotation of the rotor according to Embodiment 1 of the present invention;

[0058] Figure 8 This is a schematic diagram illustrating the phase-locked loop abnormal state identification principle of Embodiment 1 of the present invention. Detailed Implementation

[0059] To facilitate understanding of the technical solution of the present invention by those skilled in the art, the technical solution of the present invention will now be further described in conjunction with the accompanying drawings.

[0060] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0061] Example 1

[0062] See Figure 2This embodiment discloses a method for achieving precise phase-locked loop during the start-up of a gas turbine static inverter. Based on four different frequency bands—stationary, ultra-low frequency turning, low frequency rotation, and high frequency rotation—different rotor position detection methods are used to measure the rotor position in each frequency band. Specifically, the frequency range for ultra-low frequency turning is 0 < f ≤ 0.5 Hz; the frequency range for low frequency rotation is 0.5 < f ≤ 5 Hz; and the frequency range for high frequency rotation is f > 5 Hz.

[0063] S1. When the rotor is stationary, a step excitation current I is applied to the rotor. EXC (Approximately no-load rated voltage), the motor stator will generate an induced electromotive force; the bridge voltage U A_MB U B_MB U C_MB First, perform the Park transformation to transform it into U. α_MB U β_MB Then, a second-order bandpass filter (parameter 1) is used to filter out the low-frequency DC offset component and the high-frequency harmonic component; then amplitude and phase compensation is performed to obtain the unit potential ψ. α_MB ψ β_MB Within the pulse width time (approximately 0.1 s), the unit potential is integrated, and then the initial rotor position θ is calculated using arctangent calculation. ROT_INIT The transfer function of a second-order bandpass filter is as follows:

[0064]

[0065] Where K is the filter gain, ξ is the damping coefficient, and ω0 is the center frequency of the second-order bandpass filter.

[0066] The method described above was verified on a combustion engine simulation test platform, and the results are as follows: Figure 3 and Figure 4 As shown, Figure 3 The waveform of the magnetic flux linkage (excitation step current) when the rotor is stationary is shown. Curves 1, 2, and 3 represent the bridge ψ values ​​when the rotor is stationary. α Bridge ψ β and excitation current, Figure 4 The figure shows the error waveform between the initial position and the actual position of the rotor. As can be seen from the figure, the error in the detection of the initial position of the rotor is within 1°, indicating that the detection method of the present invention for the initial position of the rotor when the rotor is stationary has high accuracy.

[0067] S2. When the rotor is in ultra-low frequency turning, the bridge voltage U α_MB U β_MB The amplitude is weak and the high-frequency harmonic components are high. A second-order bandpass filter (parameter 1) is used to filter out the high-frequency harmonic components of the bridge voltage and effectively improve the judgment amplitude. Then, amplitude and phase compensation are performed to obtain the unit's flux linkage ψ. α_MB ψ β_MBThen, the rotor position θ is calculated using arctangent calculation. ROT . Figure 5 This is the magnetic flux waveform of the unit during ultra-low frequency rotor turning. Curves 4 and 5 are the bridge ψ during ultra-low frequency turning, respectively. α and bridge ψ β Both amplitudes exceed 0.4 pu and there is no high-frequency interference, effectively improving measurement accuracy.

[0068] S3. When the rotor is rotating at a low frequency.

[0069] When the rotor rotates at a low frequency (0.5 < f ≤ 5 Hz), the bridge voltage U α_MB U β_MB The amplitude is weak and greatly affected by the machine-side resistance; the terminal potential E is first obtained through the first machine-side voltage equation. α_MB E β_MB The influence of the generator-side resistance is eliminated; then, a second-order bandpass filter (parameter 1) is used to filter out the high-frequency harmonic components of the generator terminal potential and effectively improve the judgment amplitude; finally, amplitude and phase compensation are performed to obtain the unit flux linkage ψ. α_MB ψ β_MB Then, the rotor position θ is calculated using arctangent calculation. ROT .

[0070] The calculation formula for the voltage equation on the first machine side is as follows:

[0071]

[0072] In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB R is the bridge voltage, R is the machine-side resistance, and I is the bridge voltage. α_MB I β_MB It is the bridge current.

[0073] Figure 6 This is the magnetic flux waveform of the unit when the rotor is rotating at low frequency. Curves 6 and 7 are the bridge ψ during low-frequency rotation, respectively. α and bridge ψ β By filtering out the influence of the generator side resistance, the change in the unit's magnetic flux can be accurately obtained, thereby obtaining the rotor position of the unit.

[0074] S4. When the rotor is rotating at high frequency, the bridge voltage U α_MB U β_MB The commutation voltage gap is relatively large; the terminal potential E is first obtained through the second-side voltage equation. α_MB E β_MB The curve is smoothed using the least squares method; then, a second-order bandpass filter (parameter 2) is used to filter out the high-frequency harmonic components of the generator terminal potential; finally, amplitude and phase compensation are performed to obtain the unit flux linkage ψ.α_MB ψ β_MB Then, the rotor position θ is calculated using arctangent calculation. ROT .

[0075] The calculation formula for the second machine-side voltage equation is as follows:

[0076]

[0077] In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current.

[0078] Figure 7 This is the electromotive force waveform of the unit when the rotor is rotating at high frequency. Curves 8 and 9 are the bridge ψ during high-frequency rotation, respectively. α and bridge ψ β By repairing the commutation voltage gap, the change in the unit's magnetic flux can be accurately obtained, thereby determining the rotor position of the unit.

[0079] It should be noted that the parameter settings of the second-order bandpass filter in step S4 of this embodiment are different from those in steps S1-S3, which can more effectively filter out harmonic components other than the required frequency.

[0080] See Figure 8 The present invention also includes a detection process for phase-locked loop anomalies:

[0081] S5. The rotor position detection module determines the theoretically conducting thyristor THY based on the rotor position measured in steps S1-S4. SEL_X .

[0082] S6. Based on the bridge current, the pulse trigger identification module determines the actual conducting thyristor THY. X .

[0083] S7, if the THY in step S5 SEL_X With step S6, THY X If they are different, and the changes in rotor position are considered, a phase-locked loop abnormality can be determined.

[0084] This invention divides the rotor frequency band into four bands: stationary, ultra-low frequency turning, low frequency rotation, and high frequency rotation. Because the electrical characteristics of these bands differ significantly, this invention employs different rotor position detection methods to specifically eliminate the different electrical characteristics of each band, thereby accurately measuring the rotor position in each band and achieving precise phase-locking during the startup process of the gas turbine stationary inverter. Simultaneously, a second-order bandpass filter is used to more effectively filter out low-frequency DC offset components and high-frequency harmonic components; and when the rotor is rotating at high frequency, the least squares method is used to smooth the terminal potential, bridging the commutation voltage gap and improving the accuracy of rotor position measurement.

[0085] Example 2

[0086] This embodiment discloses a system for achieving precise phase-locked loop (PLL) during the start-up of a gas turbine static inverter, comprising:

[0087] Judgment module: used to determine whether the rotor is in one of four different frequency bands: stationary, ultra-low frequency turning, low frequency rotation, or high frequency rotation, based on the change in rotor position.

[0088] Processing module: Used to measure the rotor position of each frequency band by using different rotor position detection methods according to the different frequency bands in which the rotor is located.

[0089] The processing module includes a static processing unit, an ultra-low frequency processing unit, a low frequency processing unit, and a high frequency processing unit.

[0090] The static processing unit includes:

[0091] Static converter unit; used to convert the bridge voltage U of the motor stator A_MB U B_MB U C_MB Perform the Park transformation to become U α_MB U β_MB .

[0092] The static filtering unit processes U through a second-order bandpass filter. α_MB U β_MB .

[0093] The static compensation unit is used to process the U... α_MB U β_MB Amplitude and phase compensation are performed to obtain the unit's electromotive force Ψ. α_MB Ψ β_MB .

[0094] The static integrator unit is used to integrate the potential of the above-mentioned unit separately within the pulse width time.

[0095] The static arctangent unit is used to perform arctangent calculations on the integrated unit electromotive force to obtain the initial rotor position.

[0096] The ultra-low frequency processing unit includes:

[0097] The ultra-low frequency converter unit is used to convert the bridge voltage U of the motor stator. A_MB U B_MB U C_MB Perform the Park transformation to become U α_MB U β_MB .

[0098] The ultra-low frequency filtering unit processes U through a second-order bandpass filter. α_MB U β_MB .

[0099] Ultra-low frequency compensation unit, used for processing U α_MB U β_MB Amplitude and phase compensation are performed to obtain the unit's electromotive force Ψ. α_MB Ψ β_MB .

[0100] The ultra-low frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

[0101] The low-frequency processing unit includes:

[0102] The low-frequency conversion unit is used to convert the bridge voltage U of the motor stator. A_MB U B_MB U C_MB Perform the Park transformation to become U α_MB U β_MB .

[0103] The first machine-side unit is used to obtain the terminal potential E through the first machine-side voltage equation. α_MB E β_MB .

[0104] The low-frequency filtering unit is used to process the terminal potential E through a second-order bandpass filter. α_MB E β_MB .

[0105] Low-frequency compensation unit, used to adjust the terminal potential E α_MB E β_MB Amplitude and phase compensation are performed to obtain the unit's magnetic flux Ψ α_MB Ψ β_MB .

[0106] The low-frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

[0107] The high-frequency processing unit includes:

[0108] The high-frequency conversion unit is used to convert the bridge voltage U of the motor stator. A_MB U B_MB UC_MB Perform the Park transformation to become U α_MB U β_MB .

[0109] The second machine-side unit is used to obtain the terminal potential E through the second machine-side voltage equation. α_MB E β_MB .

[0110] The high-frequency smoothing unit uses the least squares method to smooth the curve.

[0111] The high-frequency filtering unit is used to process the terminal potential E through a second-order bandpass filter. α_MB E β_MB .

[0112] High-frequency compensation unit, used to adjust the terminal potential E α_MB E β_MB Amplitude and phase compensation are performed to obtain the unit's magnetic flux Ψ α_MB Ψ β_MB .

[0113] The high-frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

[0114] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0115] The above embodiments are merely examples of implementation methods of the invention. The scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for achieving precise phase-locked loop during startup of a gas turbine static frequency converter, characterized in that: Based on the changes in rotor position, the rotor is determined to be in one of four different frequency bands: stationary, ultra-low frequency turning, low frequency rotation, or high frequency rotation. The frequency range of ultra-low frequency turning is 0 < f ≤ 0.5 Hz, the frequency range of low frequency rotation is 0.5 < f ≤ 5 Hz, and the frequency range of high frequency rotation is f > 5 Hz. Different rotor position detection methods are used to measure the rotor position in each frequency band according to the different frequency bands in which the rotor is located. When the rotor is rotating at a low frequency, the process includes the following steps: S3. Perform Park transformation on the bridge voltage of the motor stator, obtain the terminal potential through the first machine side voltage equation, process it through a second-order bandpass filter, perform amplitude and phase compensation to obtain the unit flux linkage, and then perform arctangent calculation to obtain the rotor position at this time. The calculation formula for the voltage equation on the first machine side is as follows: In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current; When the rotor is rotating at a high frequency, the following steps are included: S4. Perform Park transformation on the bridge voltage of the motor stator, obtain the terminal potential through the second side voltage equation, smooth the obtained curve, apply a second-order bandpass filter, and then perform amplitude and phase compensation to obtain the unit flux linkage; finally, calculate the rotor position using arctangent calculation. The calculation formula for the voltage equation on the second machine side is as follows: In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current.

2. The method for achieving precise phase-locked starting of a gas turbine static frequency converter according to claim 1, characterized in that: When the rotor is stationary, the following steps are included: S1. The motor stator bridge voltage is transformed by Park, then processed by a second-order bandpass filter, and then amplitude and phase compensation is performed to obtain the unit potential. The unit potential is integrated within the pulse width time, and then the initial rotor position is calculated by arctangent calculation.

3. The method for achieving precise phase-locked starting of a gas turbine static frequency converter according to claim 1, characterized in that: When the rotor is in ultra-low frequency turning, the following steps are included: S2. The motor stator bridge voltage is transformed by Park, then processed by a second-order bandpass filter, and then amplitude and phase compensation is performed to obtain the unit electromotive force. Finally, the rotor position is calculated by arctangent calculation.

4. The method for achieving precise phase-locked starting of a gas turbine static frequency converter according to any one of claims 1-3, characterized in that: It also includes the detection process for phase-locked loop anomalies: S5. Based on the rotor position measured by the method described above, determine the theoretically conducting thyristor THY. SEL_X ; S6. Based on the bridge current, determine the actual conducting thyristor THY. X ; S7, if the THY in step S5 SEL_X With step S6, THY X If they are different, and the changes in rotor position are considered, a phase-locked loop anomaly can be determined.

5. A system for achieving precise phase-locked loop starting of a gas turbine static frequency converter, characterized in that: include: Judgment module: It is used to determine whether the rotor is stationary, in ultra-low frequency turning, in low frequency rotation or in high frequency rotation based on the change of rotor position. The frequency range of ultra-low frequency turning is 0 < f ≤ 0.5 Hz, the frequency range of low frequency rotation is 0.5 < f ≤ 5 Hz, and the frequency range of high frequency rotation is f > 5 Hz. Processing module: Used to measure the rotor position in each frequency band by employing different rotor position detection methods according to the different frequency bands in which the rotor is located; The processing module includes a low-frequency processing unit, which includes: The low-frequency conversion unit is used to perform Park conversion on the bridge voltage of the motor stator. The first machine-side unit is used to obtain the terminal potential through the first machine-side voltage equation; The calculation formula for the voltage equation on the first machine side is as follows: In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current; The low-frequency filtering unit is used to process the terminal potential through a second-order bandpass filter. The low-frequency compensation unit is used to compensate the amplitude and phase of the generator terminal potential to obtain the generator flux linkage; The low-frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time; Includes a high-frequency processing unit, which includes: The high-frequency conversion unit is used to convert the bridge voltage of the motor stator into a Parker voltage. The second machine-side unit is used to obtain the terminal potential through the second machine-side voltage equation; The calculation formula for the voltage equation on the second machine side is as follows: In the formula, E α_MB E β_MB It is the terminal potential, U α_MB U β_MB This is the bridge voltage, R is the machine-side resistance, L is the machine-side inductance, and I... α_MB I β_MB It is the bridge current; The high-frequency smoothing unit uses the least squares method to smooth the curve. The high-frequency filtering unit is used to process the terminal potential through a second-order bandpass filter. The high-frequency compensation unit is used to compensate the amplitude and phase of the terminal potential to obtain the unit's magnetic flux. The high-frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

6. The system for achieving precise phase-locked starting of a gas turbine static frequency converter according to claim 5, characterized in that: The processing module includes a static processing unit, which includes: Static conversion unit; used to perform Park conversion on the bridge voltage of the motor stator. The static filtering unit processes the transformed bridge voltage through a second-order bandpass filter. The static compensation unit is used to perform amplitude and phase compensation to obtain the unit's electromotive force. The static integrator unit is used to integrate the potential of the above-mentioned units separately within the pulse width time. The static arctangent unit is used to perform arctangent calculations on the integrated unit electromotive force to obtain the initial rotor position.

7. The system for achieving precise phase-locked starting of a gas turbine static frequency converter according to claim 5, characterized in that: The processing module includes an ultra-low frequency processing unit, which includes: The ultra-low frequency converter unit is used to perform Park conversion on the bridge voltage of the motor stator. The ultra-low frequency filtering unit processes the transformed bridge voltage through a second-order bandpass filter. The ultra-low frequency compensation unit is used to perform amplitude and phase compensation to obtain the unit's electromotive force; The ultra-low frequency arctangent unit is used to perform arctangent calculations to determine the rotor position at this time.

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