This paper mainly studies the main circuit topology, the working principle, modulation technique and control strategy of the STATCOM based on H-bridge. The STATCOM direct power control algorithm based on the virtual flux is used to control the AC side reactive power compensation, and in accordance with the principle of conservation of power, the DC side voltage imbalance factors are analyzed, a...

Three-level neutral-point clamped (NPC) inverters are widely used in the new energy power generation, motor drive, and many other occasions. However, voltage imbalance of an NPC inverter will affect output system, control neutral point has become a popular research topic. In this paper, compensation-voltage-injection-based balancing method is proposed. During switching cycle, average value mode...

This article proposed a novel topology of dynamic voltage regulator using transformer and PWM multi-level AC/AC converter. In this paper for finding the best value of duty ratio for switches to minimize the THD, the GA algorithm has been used and THD output voltage is assumed to be fitness function. The proposed voltage regulator employs multi-level AC/AC converter to generate compensation volt...

Radio frequency impairments such as in-phase/quadrature-phase (IQ) imbalances can result in a severe performance degradation in direct-conversion architecture-based communication systems. In this paper, we consider the case of transmitter and receiver IQ imbalance together with frequency selective channel distortion. The proposed training-based schemes can decouple the compensation of transmitt...

This paper presents a low-complexity adaptive feedforward I/Q imbalance compensation algorithm. The feed-forward solution has guaranteed stability. Due to its blind nature the algorithm is easily incorporated into an existing receiver design. The algorithm uses three estimators to obtain the necessary parameters for the I/Q imbalance compensation structure. The algorithm complexity is low due t...

Zero-IF receivers are gaining interest because they enable low-cost WLAN OFDM terminals. However, Zero-IF receivers introduce IQ imbalance which may have a huge impact on the performance. Rather than increasing component cost to decrease the IQ imbalance, an alternative is to tolerate the IQ imbalance and compensate it digitally. Current solutions converge too slow for bursty WLAN communication...

In this paper, a new approach is proposed for voltage and current harmonics compensation in grid-connected microgrids (MGs). If sensitive loads are connected to the point of common coupling (PCC), compensation is carried out in order to reduce PCC voltage harmonics. In absence of sensitive loads at PCC, current harmonics compensation scenario is selected in order to avoid excessive injection of...

electric arc furnace (eaf) is one of the largest loads in electric power systems. it is highly time varying and nonlinear. its reactive power variations cause voltage fluctuations in nearby system which is known as flicker. on the other hand the nonlinear voltage-current characteristic causes strong voltage and current harmonics in eaf. to this end flexible ac transmission systems (facts) techn...

With the development of critical loads, power quality problem has become particularly important and poor power quality will be cause many adverse effects and the cost of many deaths will follow. To improve power quality and protection of sensitive loads against grid disturbances have been used new equipment based on power electronics similar FACTs devices, they are Custom Power. One of the most...

Now-a-days for effective load compensation, a conventional three-level neutral point clamped (CNPC) inverter topology is more preferably used. This compensator, however, faces the problems of additional clamping diodes, which reduces the redundant switching states and improves the problem of capacitor voltage imbalance; further increasing the inverter cost. In this paper, a detailed analysis of...