Static var generator anti-interference controller and design method thereof

Abstract

The invention discloses a static var generator anti-interference controller and a design method thereof. The controller comprises an input unit, a coordinate transformation unit, a DC voltage adjustment module, a disturbance observation unit 1, a disturbance observation unit 2, a power factor adjustment module, a disturbance observation unit 3 and an SVPWM unit. The disturbance observation units of the invention are used to equivalently regard a difference between the actual object caused by the external disturbance and the change of system parameters and an ideal model as a control input end,equivalent interference is observed, the same amount of compensation is added in the control, and the suppression of the interference is achieved. According to the invention, parameters other than state variables are regarded as uncertainties, and the disturbance observation units are used for estimation. The structural model is simplified, the design idea of the controller is clear, the control method is simplified, and the implementation is easy. The invention adopts the idea of a back step method, a control scheme is gradually designed, and the design process of the controller is structuralized.

Description

technical field [0001] The invention relates to a direct current control method for a static var generator, in particular to a static var generator anti-interference controller and a design method thereof. Background technique [0002] The static var generator is a new type of reactive power compensation device based on a self-commutated converter circuit. The static var generator based on a rectifier (PWM rectifier) ​​topology combined with pulse width modulation technology is connected to the grid through a reactor. The rectifier A capacitor is added on the DC side to stabilize the DC side voltage and exchange energy with the grid. Adopt appropriate control strategies to control the amplitude and phase of the AC side voltage of the rectifier by controlling the on-off of the switch tube, or use direct current control to control the output current of the rectifier so that the static var generator emits or absorbs the grid current. The reactive component realizes the purpose...

AI Technical Summary

Problems solved by technology

However, this method requires a higher switching frequency, so it has higher requirements for switching elements; the hysteresis PWM control method can improve the response speed of the current, and the dynamic tracking effect is good, but it has higher requirements for the grid-side inductance, and the switching loss is also obvious. increase

[0004] In summary, in the research on the control of static var generators, in terms of controller design and control effects, the existing technology has the following deficiencies: First, the existing static var generator control methods are dependent on system parameters Strong, the control effect is obviously affected by the parameters

Second, some existing control methods have high requirements on the switching elements of the static var generator, which greatly increases the cost of reactive power compensation

Third, in order to achieve the ideal control effect, more than two control algorithms are used for composite control, and the designed controller is more complicated, which increases the difficulty of implementation

Images