Virtual inertia control system and virtual inertia control method for double-fed pumped storage generator set

Abstract

The invention relates to a virtual inertia control system and a virtual inertia control method for a double-fed pumped storage generator set. The virtual inertia control system comprises a Washout filter module, a proportional differential regulator module and a one-order low pass filter module, wherein the Washout filter module is used for blocking a steady state input signal, so that the control process of the control system is not influenced by a steady frequency deviation; the proportional differential regulator module is used for controlling an output power reference value of the double-fed pumped storage generator set through frequency modulation auxiliary power, so that the output power reference value of the double-fed pumped storage generator set is associated with the power grid frequency; when the power grid frequency is changed, the output power reference value of the double-fed pumped storage generator set is correspondingly adjusted so as to realize frequency modulation of the power grid frequency; and the one-order low pass filter module is used for eliminating a high-frequency noise signal so as to reduce the interference of the external signal on the control system. According to the virtual inertia control system and the virtual inertia control method for the double-fed pumped storage generator set provided by the invention, the operating stability of the set and the power grid frequency stability can be improved.

Description

technical field [0001] The invention belongs to the technical field of pumped storage, and relates to a virtual inertia control system and method of a doubly-fed pumped storage unit. Background technique [0002] The doubly fed pumped storage unit (Doubly Fed Pumped Storage Unit, DFPSU) has gradually become one of the mainstream units for newly built pumped storage power plants due to its advantages of adjustable speed. In recent years, with the increasing penetration of renewable energy in the power system, especially in the regional power grid, DFPSU is required not only to participate in the peak regulation of the power grid, but also to have the ability to participate in the frequency regulation of the power grid. However, the existing DFPSU power decoupling control prevents the doubly fed motor (Doubly Fed Induction Machine, DFIM) rotor from responding quickly to changes in frequency, and thus contributes little to the frequency of the entire system. At present, there ...

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Problems solved by technology

However, the existing DFPSU power decoupling control prevents the doubly fed motor (Doubly Fed Induction Machine, DFIM) rotor from responding quickly to changes in frequency, thus making little contribution to the frequency of the entire system

At present, there are no reports on the control methods of DFPSU participating in the frequency regulation of the power grid at home and abroad; although some frequency control methods have been proposed in the field of doubly-fed wind power generation and have achieved certain results, such as rotor kinetic energy control, frequency droop control, and inertial control. The power-frequency droop characteristics and inertial response characteristics of the primary frequency modulation of the generator add an auxiliary frequency control loop to release / absorb the kinetic energy of the rotor, thereby providing short-term power support for the grid; however, the above-mentioned frequency control methods lack the ability to adjust frequency, especially the system frequency In-depth research on the dynamic effect of the lowest point (frequency nadir, FN), highest point (frequency zenith, FZ) and unit speed recovery stability

In addition, in order to better play the important role of the DFPSU as a power grid dispatching tool, it is required to have frequency modulation capabilities in both power generation and electric power conditions; and most of the existing frequency modulation control methods are analyzed for the operating conditions of double-fed units as generators. There is no report on the research on the frequency modulation control method of the electric working condition of the unit; in addition, there is no in-depth research on the analysis of the DFPSU power generation, the electric working condition control parameters and the frequency modulation capability.

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