CN-122026755-A - Polymorphic perception PI control method and related device for double-fed pumped storage unit

CN122026755ACN 122026755 ACN122026755 ACN 122026755ACN-122026755-A

Abstract

The invention discloses a polymorphic perception PI control method and a relevant device for a double-fed pumped storage unit, which relate to the technical field of power system control, and the method comprises the steps of calculating a plurality of state variables for reflecting the running state of an alternating current excitation system according to real-time running signals; the method comprises the steps of selecting a state variable to be input into a multi-dimensional fuzzy inference model, enabling the multi-dimensional fuzzy inference model to be mapped into transient severity and steady-state error degree based on a preset typical fuzzy rule, dividing operation working conditions of an alternating-current excitation system according to the transient severity and the steady-state error degree, determining a corresponding preset PI control strategy according to the operation working condition types, and carrying out vector control on a machine side converter in the alternating-current excitation system under a d-q coordinate system according to the PI control strategy, wherein the dividing types comprise steady-state operation, conventional disturbance operation and extreme faults. The invention solves the problems of fixed parameters and poor adaptability of the traditional PI controller in the side control of the double-fed pumped storage unit.

Inventors

ZHONG YILIN
WANG DAMING
HUANG WEIHUANG
ZHOU YUEBIN
WU HAO
HUANG WEN

Assignees

南方电网科学研究院有限责任公司

Dates

Publication Date: 20260512
Application Date: 20251203

Claims (10)

1. A multi-state sensing PI control method for a doubly fed pumped storage unit, comprising: Collecting operation signals of an alternating current excitation system in a double-fed pumped storage unit in real time, and calculating a plurality of state variables for reflecting the operation state of the alternating current excitation system according to the operation signals; Selecting a plurality of state variables to be input into a multidimensional fuzzy inference model, so that the multidimensional fuzzy inference model is mapped into transient severity for reflecting dynamic disturbance intensity and steady error degree for reflecting steady error degree based on a preset typical fuzzy rule; Dividing the operation working conditions of the alternating current excitation system according to the transient severity and the steady-state error degree, wherein the types of division comprise steady-state operation, normal disturbance operation and extreme faults; And determining a corresponding preset PI control strategy according to the operation condition type, and performing vector control on a machine side converter in the alternating current excitation system according to the PI control strategy under a d-q coordinate system.
2. The method of claim 1, wherein the state variables include power deviation rate, rotor current ripple rate, DC bus voltage deviation rate, current distortion rate, power balance index, and transient intensity index.
3. The polymorphic perceptual PI control method for a doubly fed pumped-hydro energy storage unit as defined in claim 2, wherein said selecting a number of said state variables for input to a multidimensional fuzzy inference model such that said multidimensional fuzzy inference model maps to transient severity for reflecting dynamic disturbance intensity and steady state error degree for reflecting steady state bias degree based on preset typical fuzzy rules comprises: selecting a plurality of state variables to carry out fuzzification processing, so that the discourse domain of each state variable is divided into three fuzzy sets of small deviation, medium deviation and large deviation, and calculating membership of each state variable to the corresponding fuzzy set by adopting a triangular membership function, wherein the selected state variables comprise the power deviation rate, the direct current bus voltage deviation rate and the transient strength index; based on the membership degree, activating a corresponding IF-THEN rule in the preset typical fuzzy rule base; and performing defuzzification processing on all activated rule outputs by adopting a Mamdani fuzzy inference algorithm, and obtaining transient severity and steady-state error degree by a weighted average method.
4. The multi-state aware PI control method for a doubly fed pumped-hydro energy storage unit according to claim 1, wherein said dividing operation conditions of said ac excitation system according to said transient severity and said steady state error level includes steady state operation, normal disturbance operation and extreme faults, including: Dividing the operation condition of the alternating current excitation system into the steady-state operation condition when the transient severity and the steady-state error degree are both in a low-level interval in the preset typical fuzzy rule; dividing the operation condition of the alternating current excitation system into conventional disturbance operation conditions which are dominant by the transient error when the transient intensity is in a high-level interval in the preset typical fuzzy rule and the steady-state error degree is in a low or medium-level interval; Dividing the operation condition of the alternating current excitation system into the normal disturbance operation condition dominated by the steady state error when the transient intensity is in a middle level interval and the steady state error is in a middle or high level interval in the preset typical fuzzy rule; and when the transient severity and the steady-state error degree are both in a high-level interval in the preset typical fuzzy rule, dividing the operation working condition of the alternating current excitation system into the extreme fault working condition.
5. The polymorphic-aware PI control method for a doubly-fed pumped-hydro energy storage unit according to claim 1, wherein when the operating condition division is of the steady-state operation type, the determining a corresponding preset PI control strategy according to the operating condition type comprises: and controlling parameters of a PI controller in the alternating current excitation system to be unchanged, so that the alternating current excitation system stably operates, wherein the parameters of the PI controller comprise a proportional coefficient and an integral coefficient.
6. The multi-state aware PI control method for a doubly fed pumped-hydro energy storage unit as defined in claim 5 wherein when said operating condition split is of the type of said regular disturbance operation, said determining a corresponding preset PI control strategy based on operating condition type comprises: dynamically adjusting parameters of a PI controller in the alternating-current excitation system based on an adjusting formula of the self-adaptive PI parameter according to the transient severity and the steady-state error degree; the adjustment formula of the self-adaptive PI parameter is as follows: ; In the formula, As a result of the scaling factor to be achieved, As an original scaling factor, the scaling factor is, To deblur the processed transient severity, As a result of the integration coefficient(s), As the original integral coefficient(s), The steady state error degree after the defuzzification processing is obtained.
7. The multi-state aware PI control method for a doubly fed pumped-hydro energy storage unit as defined in claim 6 wherein when said operating condition classification is of said extreme fault type, said determining a corresponding preset PI control strategy based on operating condition type comprises: Switching a controller of a power outer loop of a machine side converter in the alternating current excitation system into a nonlinear self-adaptive active disturbance rejection proportional-integral controller; the nonlinear adaptive active disturbance rejection proportional-integral controller is configured to: receiving the power set value through a nonlinear tracking differentiator in the power set value, and outputting a corresponding tracking signal and a differentiation signal; And cascading the fal function with the PI controller to form nonlinear proportion and nonlinear integration links, so that the proportion coefficient and the integration coefficient of the PI controller carry out nonlinear self-adaptive change according to the magnitude of the power error.
8. A multi-state aware PI control system for a doubly fed pumped-storage unit comprising: The system comprises an acquisition unit, a control unit and a control unit, wherein the acquisition unit is used for acquiring operation signals of an alternating current excitation system in a doubly-fed pumped storage unit in real time, and calculating a plurality of state variables for reflecting the operation state of the alternating current excitation system according to the operation signals; The mapping unit is used for selecting a plurality of state variables to be input into a multi-dimensional fuzzy inference model, so that the multi-dimensional fuzzy inference model is mapped into transient severity for reflecting dynamic disturbance intensity and steady error degree for reflecting steady error degree based on a preset typical fuzzy rule; The dividing unit is used for dividing the operation condition of the alternating current excitation system according to the transient severity and the steady-state error degree, and the dividing types comprise steady-state operation, normal disturbance operation and extreme faults; And the control unit is used for determining a corresponding preset PI control strategy according to the operation condition type, and carrying out vector control on the machine side converter in the alternating current excitation system under a d-q coordinate system according to the PI control strategy.
9. A multi-state aware PI control device for a doubly fed pumped storage unit, the device comprising a processor and a memory: The memory is used for storing program codes and transmitting the program codes to the processor; the processor is configured to execute the multi-state aware PI control method for a double fed pumped storage unit according to any one of claims 1-7 according to instructions in the program code.
10. A computer readable storage medium for storing program code for performing the polymorphic perceived PI control method for a doubly fed pumped-storage unit according to any of claims 1-7.

Description

Polymorphic perception PI control method and related device for double-fed pumped storage unit Technical Field The invention relates to the technical field of power system control, in particular to a polymorphic perception PI control method and a related device for a double-fed pumped storage unit. Background The double-fed pumped storage unit is one kind of efficient energy storing device for peak regulation, frequency regulation and spare capacity of power system and its operation involves the coordinated control of machine side, network side and DC side. For a doubly fed pumped storage unit, the machine side control is the core of the whole system, and the performance of the machine side control directly influences the running efficiency, the stability and the power grid supporting capacity of the unit. The core goal of the machine side control is to realize accurate decoupling control of the rotor current of the doubly fed motor, the rotor current is decomposed into an active component and a reactive component based on a vector control strategy of stator voltage orientation, and a double closed loop control structure is constructed under a synchronous rotation d-q coordinate system, wherein an outer loop is a power or rotating speed loop, an inner loop current reference value is generated, an inner loop is a current loop, and the current is tracked by adjusting the output voltage of a current transformer. In the process, the PI controller is widely applied to the error adjustment of the inner ring and the outer ring due to the simple structure and easy realization, and aims to eliminate steady-state errors and provide a certain dynamic response. However, conventional PI control has drawbacks in the side application of the double-fed machine set. Firstly, a traditional PI controller depends on an accurate mathematical model, and in a double-fed pumped storage unit, because the operation condition is complex, the load mutation and the power grid disturbance are frequent, the system parameters have strong uncertainty and time variability, the traditional PI parameter setting method is difficult to adapt to dynamic changes, and the overshoot is easy to be excessively large, the adjustment time is excessively long and even the system is unstable. Secondly, the traditional PI controller has limited inhibiting capability on nonlinear factors, and particularly under nonlinear interference such as machine side converter switching action, flux linkage observation errors, power grid voltage distortion and the like, steady state errors and transient oscillations can not be effectively inhibited by simply relying on the quick response of a proportional link and the steady state correction of an integral link, and power fluctuation aggravation or equipment overload can be caused. Furthermore, the bandwidth of the conventional PI controller is limited, and the response speed of the conventional PI controller cannot meet the requirements in a scene where high dynamic performance is required. When the working condition of the unit is greatly switched or severely fails, the running point of the system is changed severely, and the fixed PI parameters are difficult to maintain the optimal performance at all working points, so that the transient process is oversized or the adjusting time is long. Disclosure of Invention The invention provides a polymorphic perception PI control method and a relevant device for a double-fed pumped storage unit, which are used for solving the problems of fixed parameters and poor adaptability of a traditional PI controller in the side control of the double-fed pumped storage unit. In view of this, a first aspect of the present application provides a multi-state aware PI control method for a doubly fed pumped-storage unit, said method comprising: Collecting operation signals of an alternating current excitation system in a double-fed pumped storage unit in real time, and calculating a plurality of state variables for reflecting the operation state of the alternating current excitation system according to the operation signals; Selecting a plurality of state variables to be input into a multidimensional fuzzy inference model, so that the multidimensional fuzzy inference model is mapped into transient severity for reflecting dynamic disturbance intensity and steady error degree for reflecting steady error degree based on a preset typical fuzzy rule; Dividing the operation working conditions of the alternating current excitation system according to the transient severity and the steady-state error degree, wherein the types of division comprise steady-state operation, normal disturbance operation and extreme faults; And determining a corresponding preset PI control strategy according to the operation condition type, and performing vector control on a machine side converter in the alternating current excitation system according to the PI control strategy under a d-q coordinate system. Optionally, t