DFIG virtual synchronous machine low voltage ride through method and device, electronic equipment and medium

Abstract

The invention discloses a DFIG virtual synchronous machine low voltage ride through control method and device, electronic equipment and a medium. According to the method, a DFIG virtual synchronous machine control method and model predictive control are combined to achieve direct control over the DFIG rotor current, the multivariable control characteristic of a model predictive control cost function is utilized, and meanwhile control over the DFIG transient flux linkage is achieved. The method is simultaneously suitable for power grid voltage symmetric and asymmetric drop faults. When the power grid voltage drops symmetrically, rotor overcurrent can be prevented, attenuation of rotor transient flux linkage is accelerated, and reactive power support is provided by changing a power referencevalue. When the power grid voltage drops asymmetrically, the method can further prevent a rotor from overcurrent, and balance and sine of the rotor current are maintained by eliminating transient andnegative sequence components in the rotor current reference value. The control system disclosed by the invention is extremely simple to implement, does not need a phase-locked loop to monitor the frequency of the power grid voltage in real time, and does not need to add an additional control loop.

Description

technical field [0001] The invention belongs to the technical field of motor control, and in particular relates to a low-voltage ride-through control method, device, electronic equipment and medium of a DFIG virtual synchronous machine based on model predictive control. Background technique [0002] With the rapid development of the field of renewable energy power generation, the proportion of renewable energy power generation systems dominated by wind power and photovoltaics in the power system is also increasing. In the modern wind power generation system, the doubly-fed induction generator (DFIG) is the most widely used and the most mature technology, which is the current mainstream model. The structure of DFIG control system is as follows: figure 1 As shown, the variable speed and constant frequency control of DFIG can be realized by controlling the generator-side converter and the grid-side converter. Traditional synchronous generators have a huge moment of inertia an...

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Problems solved by technology

[0007] The purpose of the embodiment of the present invention is to provide a DFIG virtual synchronous machine low-voltage ride-through control method, device, electronic equipment and medium based on model predi

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