Electric energy quality regulating system based on energy storing of super capacitor

Abstract

The invention relates to an electric energy quality regulating system based on energy storing of a super capacitor, which belongs to the field of electric energy quality regulation technology and is characterized by comprising a three-phase voltage type PWM (Pulse Width Modulation) rectifier 3, a bidirectional DC / DC converter 4 and the super capacitor 5; the system is connected with a power network system 1 in parallel; during normal operation, the three-phase voltage type PWM rectifier 3 is used for stabilizing DC voltage and simultaneously realizing reactive harmonic compensation; the bidirectional DC / DC converter 4 is used for controlling the charging of the super capacitor 5; when the power network system 1 has short-circuit fault, the super capacitor 5 is used for controlling the output of stable DC voltage by the bidirectional DC / DC converter 4; and the three-phase voltage type PWM rectifier 3 is used for sending out reactive power to support the voltage of the power network system 1 and improve the voltage quality. The regulating system has the capabilities of reactive harmonic compensation and low-voltage crossing and reduces equipment redundancy. The super capacitor 5 has longer service life, thereby reducing the operating cost. The system can charge the super capacitor 5, thereby saving extra charging devices.

Description

technical field [0001] The invention belongs to the technical field of power quality regulation. It involves a new type of power quality adjustment system with supercapacitors connected to the grid system in parallel to adjust the power quality of the grid system, especially the three-phase voltage PWM rectifier and the BUCK-BOOST bidirectional DC / DC rectifier in the system. The control design of the DC converter in the normal operation of the grid system and the fault operation of the grid system. Background technique [0002] With the rapid development of the national economy and science and technology, various power electronic devices are widely used, which will inevitably increase the demand for electric energy in all walks of life, and the power sector and users will pay more and more attention to power quality. [0003] Resistive and inductive loads occupy a large proportion of industrial and domestic electricity consumption. Resistive and inductive loads must absorb ...

AI Technical Summary

Problems solved by technology

When a short-circuit fault occurs in the wind power grid-connected system, the grid voltage drops. Practice shows that the voltage loop control fails at this time, resulting in STATCOM being unable to generate a large amount of reactive power to support the grid voltage.

To ensure the normal operation of STATCOM when the power grid fails, it must be provided with a stable DC side voltage, which can be maintained by adding an additional set of power supply devices that have nothing to do with the grid voltage. Will cause redundancy and idleness of equipment

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