CN-115378028-B - Subsynchronous resonance suppression method and device for wind-fire bundling serial-fed delivery system

CN115378028BCN 115378028 BCN115378028 BCN 115378028BCN-115378028-B

Abstract

The application provides a sub-synchronous resonance suppression method and device for a wind fire bundling and serial compensation delivery system, wherein dq decoupling control based on stator dynamic flux linkage compensation is adopted to superimpose a doubly-fed fan stator current through a transfer function on a rotor reference voltage of a machine side converter, and integral optimization of damping characteristics of the doubly-fed fan sub-synchronous frequency range is realized by setting phase angle and amplitude characteristics of the transfer function in the sub-synchronous frequency range. According to the application, the impedance characteristic of the sub-synchronous frequency band of the doubly-fed fan is integrally remolded, so that the damping characteristic of the sub-synchronous frequency band of the doubly-fed fan is optimized, and the suppression of the sub-synchronous resonance phenomenon of the wind fire bundling and sending system is realized.

Inventors

YI SHUXIAN
LUO JING
YAN YIAN
LU WENQING
LIANG BEIHUA
XIE HUAN
CAO TIANZHI
XIN HUANHAI
Ma Fuyilong
HUANG TIANXIAO
LI SHANYING
WANG XIAOFEI
HAO JING

Assignees

华北电力科学研究院有限责任公司
国家电网有限公司

Dates

Publication Date: 20260505
Application Date: 20220816

Claims (8)

1. A sub-synchronous resonance suppression method for a wind-fire bundling and serial-fed delivery system is characterized by comprising the following steps of: Acquiring the positive sequence impedance of the doubly-fed fan end; Superposing the doubly-fed fan stator current flow transfer function onto the machine side converter rotor reference voltage; adjusting the damping characteristic of the doubly fed fan end impedance in the sub-synchronous frequency band through a setting transfer function; The method for superposing the transfer function of the doubly-fed fan stator current to the reference voltage of the machine side converter rotor comprises the steps of superposing the d-axis component and the q-axis component of the stator current in a synchronous rotation coordinate system And The feedback is carried out through a transfer function R(s), and then the feedback is superimposed on the components U rd_ref and U rq_ref of the d axis and q axis of the rotor reference voltage of the machine side converter; Setting the control parameter of the transfer function R(s) to enable the phase of the transfer function H'(s) in the sub-synchronous frequency range to be between minus 90 degrees and 0 degrees; Optimizing the damping characteristic of the doubly-fed fan in the sub-synchronous frequency band through a transfer function R(s) so as to improve the sub-synchronous stability of the wind-fire bundling system after series compensation; Said setting of the control parameters of the transfer function R(s) to bring the transfer function H'(s) between [ -90 °,0 ° ] in the subsynchronous frequency band comprises: ; Wherein, let the ; Wherein L s is the inductance of the stator winding, L r is the inductance of the rotor winding, L m is the excitation inductance between the stator winding and the rotor winding, and G i represents the current loop controller gain; Original transfer function Is of the phase of In the original transfer function Introducing a transfer function R(s) such that the sub-synchronous frequency band phase of the transfer function R'(s) is at Between such that The phase is between-90 DEG, 0 DEG in the sub-synchronous frequency band.
2. The method for suppressing sub-synchronous resonance of a wind-fire bundling fed-through series-fed-out system according to claim 1, wherein the step of obtaining the positive sequence impedance of the doubly-fed fan machine end comprises the steps of: The dynamic compensation mode of dq decoupling and stator flux linkage is adopted in the inner ring of the machine side converter to realize dq decoupling control; And after dq decoupling control is realized, transforming the dq impedance matrix under the synchronous rotation coordinate system into a positive and negative sequence impedance matrix under the static coordinate system to obtain the positive sequence impedance of the doubly-fed fan machine end.
3. The method for suppressing sub-synchronous resonance of a wind-fire bundling fed-through series-fed-out system according to claim 1, wherein the adjusting the damping characteristic of the doubly-fed fan-end impedance in the sub-synchronous frequency band by setting the transfer function comprises: introducing additional damping control of the machine side converter based on stator current feedback to obtain new doubly-fed fan machine end impedance characteristics; According to the new impedance characteristic of the machine end, the control parameter of the transfer function R(s) is set, and the phase frequency and amplitude frequency characteristics of the R(s) in the sub-synchronous frequency range are adjusted, so that the damping level of the doubly-fed fan in the sub-synchronous frequency range is optimized.
4. The utility model provides a wind fire bundling is through cluster compensation delivery system subsynchronous resonance suppression device which characterized in that includes: the superposition unit is used for superposing the stator current of the wind-fire bundling through the series compensation delivery system on the reference voltage of the rotor-side converter; The positive sequence impedance acquisition unit is used for acquiring positive sequence impedance of the stator port of the doubly-fed wind turbine; The damping characteristic changing unit is used for obtaining the impedance characteristic of the stator port according to the positive sequence impedance so as to change the damping characteristic of the original doubly-fed fan machine end impedance in the sub-synchronous frequency band; The superimposing unit includes: A component superposition module for superposing d-axis and q-axis components of the stator current in the synchronous rotation coordinate system And The feedback is carried out through a transfer function R(s), and then the feedback is superimposed on the components U rd_ref and U rq_ref of the d axis and q axis of the rotor reference voltage of the machine side converter; The apparatus further comprises: A setting module for setting the control parameter of the transfer function R(s) to make the phase of the transfer function H'(s) in the sub-synchronous frequency range between [ -90 DEG, 0 DEG ]; the stability improving module is used for improving the damping characteristic of the doubly-fed fan in the sub-synchronous frequency band through a transfer function R(s) so as to improve the sub-synchronous stability of the wind fire bundling and delivering system; Wherein, the ; Wherein, the ; Wherein L s is the inductance of the stator winding, L r is the inductance of the rotor winding, L m is the excitation inductance between the stator winding and the rotor winding, and G i represents the current loop controller gain; Original transfer function Is of the phase of In the original transfer function Introducing a transfer function R(s) such that the sub-synchronous frequency band phase of the transfer function R'(s) is at Between such that The phase is between-90 DEG, 0 DEG in the sub-synchronous frequency band.
5. The wind fire bundling and serial feed delivery system subsynchronous resonance suppression device according to claim 4, wherein the positive sequence impedance acquisition unit comprises: the decoupling module is used for realizing dq decoupling control by adopting a dq decoupling compensation and stator flux linkage dynamic compensation mode in the inner ring of the machine side converter; and the matrix transformation module is used for transforming the dq impedance matrix under the synchronous rotation coordinate system into the positive and negative sequence impedance matrix under the static coordinate system to obtain the positive sequence impedance of the doubly-fed fan machine end after the dq decoupling control is realized.
6. The wind-fire bundling and series-fed delivery system subsynchronous resonance suppression device according to claim 4, wherein said damping characteristic changing unit comprises: The new impedance characteristic acquisition module is used for introducing additional damping control of the machine side converter based on stator current feedback to obtain new machine side impedance characteristics on the positive sequence impedance obtained stator port impedance characteristics; And the damping level changing module is used for setting the control parameter of the transfer function R(s) according to the new machine end impedance characteristic so as to change the damping level of the doubly-fed fan in the subsynchronous frequency band.
7. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor performs the steps of the wind fire bundling via serial feed delivery system subsynchronous resonance suppression method of any one of claims 1 to 3 when the program is executed.
8. A computer readable storage medium having stored thereon a computer program, which when executed by a processor, performs the steps of the wind fire bundling via serial feed delivery system subsynchronous resonance suppression method of any one of claims 1 to 3.

Description

Subsynchronous resonance suppression method and device for wind-fire bundling serial-fed delivery system Technical Field The application belongs to the technical field of wind power generation, and particularly relates to a method and a device for restraining subsynchronous resonance of a wind-fire bundling and serial-compensation delivery system. Background When the wind power production base is far away from the electricity load center and long-distance trans-regional power transmission is needed, the mode of bundling wind and fire and serial compensation and external transmission is adopted, and thermal power and wind power are transmitted through the serial compensation-carrying alternating current power transmission line, so that the adjustability of the thermal power can be utilized to stabilize the fluctuation and randomness of wind power output, and the serial compensation-carrying alternating current power transmission line can be utilized to improve the alternating current channel transmission capacity. However, after wind power is connected, subsynchronous interaction among wind power, thermal power and series compensation systems becomes more complex, and the risk of triggering shafting torsional vibration of the thermal power unit and subsynchronous electric resonance of a power grid is increased. The traditional wind turbine generator sub-synchronous resonance mechanism analysis and optimization method based on the Nyquist criterion has strong dependence on the structure and parameters of a power grid system, and can only evaluate stability and reform and optimize aiming at a specific frequency band or a frequency point, so that the impedance characteristic of the wind turbine generator is difficult to integrally optimize in the whole sub-synchronous frequency band. Disclosure of Invention The application provides a method and a device for restraining subsynchronous resonance of a wind-fire bundling and series-fed delivery system, which are used for solving the problems that subsynchronous interaction among wind power, thermal power and series-fed systems becomes more complex after a large-scale wind power base is connected, and the risk of causing shafting torsional vibration of a thermal power unit and subsynchronous electric resonance of a power grid is increased. According to a first aspect of the present application, there is provided a wind-fire bundling and serial-fed delivery system subsynchronous resonance suppression method, comprising: Acquiring the positive sequence impedance of the doubly-fed fan end; Superposing the doubly-fed fan stator current flow transfer function onto the machine side converter rotor reference voltage; and adjusting the damping characteristic of the doubly-fed fan end impedance in the sub-synchronous frequency band through the setting transfer function. In one embodiment, superimposing a wind fire bundle over a stator current of a doubly fed wind turbine in a series fed delivery system via a transfer function onto a machine side converter rotor reference voltage includes: The d-axis and q-axis components i sd and i sq of the doubly-fed fan stator current in the synchronous rotation coordinate system are fed back through a transfer function R(s) and then are superimposed on the d-axis and q-axis components U rd_ref and U rq_ref of the rotor reference voltage of the machine side converter. In an embodiment, the method for suppressing sub-synchronous resonance of the wind-fire bundling via serial-fed delivery system further comprises: Setting the control parameter of the transfer function R(s) to enable the phase of the transfer function H'(s) in the sub-synchronous frequency range to be between minus 90 degrees and 0 degrees; and the damping characteristic of the doubly-fed fan in the sub-synchronous frequency range is optimized through a transfer function R(s), so that the sub-synchronous stability of the wind-fire bundling and delivering system is improved. In one embodiment, obtaining doubly fed fan machine end positive sequence impedance includes: The dq decoupling control is realized in the inner ring of the machine side converter by adopting a dq decoupling and stator flux linkage dynamic compensation mode; After dq decoupling control is realized, the dq impedance matrix under the synchronous rotation coordinate system is transformed to the positive and negative sequence impedance matrix under the static coordinate system, so that the positive sequence impedance of the doubly-fed fan machine end is obtained. In an embodiment, adjusting the damping characteristic of the impedance of the doubly-fed fan at the sub-synchronous frequency band by setting the transfer function includes: introducing additional damping control of a machine side converter based on stator current feedback to obtain new fan end impedance characteristics; And according to the impedance characteristic of the machine end of the new fan, setting the control parameter of the transfer fun