Voltage dips at the terminals of wind power installations

Abstract

This article gives an overview of the kind of voltage dips that can be expected at the terminals of a wind power installation.The overview is based on the study of those dips at the terminals of industrial installations and provides a guideline for the testing of wind power installations against voltage dips. For voltage dips due to faults, a classification into different types is presented. Five types appear at the terminals of sensitive equipment and thus have to be included when testing the wind power installation against disturbances coming from the grid. A distinction is made between installations connected at transmission level and those connected at distribution level.For the latter the phase angle jump has to be considered. Dips due to other causes (motor, transformer and capacitor switching) are briefly discussed as well as the voltage recovery after a dip. Finally some thoughts are presented on the way in which voltage tolerance requirements should be part of the design process for wind power installations.

Clustered PV inverters in LV networks: An overview of impacts and comparison of voltage control strategies

“…Short circuits (in HV, MV and LV networks) and high load start-ups are the main reasons of voltage dip. Since short circuit can be occurred in a symmetrical or unsymmetrical manner depending on fault type, voltage dips can also be in various types [34].…”

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“…95 A special concern in this respect is a sudden loss of generation, particularly in scenarios with large DG penetration. For example, at transmission levels, large wind parks may adversely affect the stability of the network in the case of a sudden disconnection due to a network disturbance.…”

Computation of reactive power in the framework of the new Spanish grid code using test fields of wind turbines submitted to voltage dips

“…Low voltage ride through is particularly important to maintain voltage stability, especially in areas with high concentration of wind power generation -wind turbines were disconnected from the grid when the terminal voltage fell below 80% according to the previous practice, [5]-. Premature tripping of wind generators due to power system disturbances may put in risk the stability of the system, wich contributes to the amplification of the disturbance, [6], [7].…”

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