Wide‐area measurement system‐based transient excitation boosting control to improve power system transient stability

Abstract

Transient excitation boosting control (TEBC) is a cost-effective emergency control technique to improve the power system transient stability. However, it is found in this study that the conventional TEBCs have some drawbacks and may be ineffective or even worsen the system stability in some cases. To overcome these problems, a novel widearea measurement system (WAMS)-based TEBC (WTEBC) is proposed in this study. The proposed control law is as follows: boosting the excitation of the critical machines (CMs) in the critical swing and stopping their excitation boosting as the rotor angles of the CMs drop below a threshold after the critical swing. The implementations of the above control law in the special protection system are also provided. The simulation results from the 4-machine system and the China Southern power grid prove the superiority of the WTEBC over the conventional TEBCs. Furthermore, it also indicates that the stabilising effect is quite significant as long as the round-trip WAMS delay is <0.3 s, which further confirms the feasibility of the WTEBC in the practical engineering.

Active-Current Control of Large-Scale Wind Turbines for Power System Transient Stability Improvement Based on Perturbation Estimation Approach

“…A transmission system, consisting of a low-speed drive shaft, gearbox, and a high-speed drive shaft, transmits the mechanical power Pm to the wound induction generator, which can be modeled as a two-mass shaft model in (5). A transmission system, consisting of a low-speed drive shaft, gearbox, and a high-speed drive shaft, transmits the mechanical power P m to the wound induction generator, which can be modeled as a two-mass shaft model in (5).…”

“…A transient stability control strategy (TSCS) is essential to prevent a system from losing synchronism. The traditional TSCS includes generator tripping [2], load shedding [3,4], and excitation boosting control [5], etc. However, the improvement provided by the excitation boosting control is limited due to the restriction of maximum exciting current.…”

Wide‐area measurement system‐based model‐free approach of post‐fault rotor angle trajectory prediction for on‐line transient instability detection

“…The model can be represented by a set of non-linear differential and algebraic equations. For the multi-machine power systems, the motion equations of generator i can be expressed as (1), where δ i is the angle of generator i; ω i is the angular velocity with respect to a synchronous frame of the generator i; M i is the inertia constant of generator i; P mi and P ei are the mechanical power input and electric power output of generator i; G ii is the self-conductance of generator i; G ij is the transfer conductance between generator i and generator j; B ij is the transfer susceptance between generator i and generator j; E i is the constant voltage of generator i; δ ij is the angle differences between generator i and generator j…”

“…In recent years, power systems are confronted with great challenges due to their increasing scale and more complex structure. Since the advancement of wide-area measurement system (WAMS) based on synchronised phasor measurements has made it possible to gain real-time information of transient stability status in power systems [1], the power system transient stability assessment and emergency control have received renewed interests. WAMS has provided key foundation for the development of online transient stability analysis based on the real-time response data [2].…”

Modeling, Sizing, and Control of an Excitation Booster for Enhancement of Synchronous Generators Fault Ride-Through Capability: Experimental Validation

“…The second group adds a signal to the reference voltage of the excitation system. This signal either depends on the rotor speed deviation that is locally measured [5], on a decaying pulse triggered by a remote signal [12] or on a decision algorithm based in a Wide Area Measurement System (WAMS) and a fast simulator [13].…”