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Summary: Classic control methods commonly used for a unified power quality conditioner (UPQC) include the following: proportional integral (PI) control, proportional resonance (PR) control, and repetitive control. Generally, the main weaknesses of these control methods are poor compensation accuracy and low response speed. In this article, in order to enhance the overall performance of the system, we introduce an innovative nonlinear control strategy based on the Lyapunov function for the three‐phase three‐wire neutral‐point clamp (NPC) type three‐level UPQC. We first develop the mathematical UPQC model, then obtain from the model the control law which we use to construct the switching function by creating the Lyapunov function, thus avoiding the introduction of closed‐loop feedback. The suggested strategy also achieves system stability and dynamic performance by selecting appropriate parameters, after which a carrier‐based pulse width modulation control method based on the injected zero‐sequence component is applied to maintain the stability and balance of the DC‐side capacitor voltage. In addition, both numerical simulation and comparison of experimental results using traditional PI control, passivity‐based control methods, and sliding mode control shows that the proposed nonlinear control strategy for three‐phase three‐wire NPC type three‐level UPQC has an excellent response speed and compensation efficiency. [ABSTRACT FROM AUTHOR]

Corin is a serine protease that activates atrial natriuretic peptide (ANP). CORIN gene variants have been reported in patients with hypertension. To date, however, the prevalence of CORIN variants in hypertensive patients remains unknown. To understand the prevalence and functional significance of CORIN variants in hypertension, we sequenced CORIN exons in 300 normal and 401 hypertensive individuals in a Chinese population and identified nine nonsynonymous variants, of which eight were not characterized previously. Among them, variants c.131A > G (p.Tyr13Cys), c.376G > T (p.Asp95Tyr), c.1094T > G (p.Leu334Trp), and c.1667G > A (p.Arg525His) occurred similarly in both normal and hypertensive individuals. Variants c1139G > A (p.Arg349His), c.2689C > T (p.Pro866Ser), and c.2864C > T (p.Thr924Met) were found once each in hypertensive individuals. Variant c.1683G > T (p.Arg530Ser) occurred preferentially in hypertensive individuals [10/401 (2.5%) vs. 1/300 (0.3%) in normal individuals; P = 0.023], which was confirmed in another independent cohort [9/368 (2.44%) in hypertensive and 2/377 (0.53%) in normal individuals; P = 0.033]. In biochemical and cell-based functional studies, variants p.Arg530Ser and p.Thr924Met, but not p.Tyr13Cys, p.Asp95Tyr, p.Leu334Trp, p.Arg349His, p.Arg525His, and p.Pro866Ser, exhibited reduced pro-ANP processing activity, which was caused by endoplasmic reticulum retention and poor zymogen activation, respectively. These results indicate that genetic variants impairing corin function are not uncommon in general populations and that such variants may be an important contributing factor in hypertension. [ABSTRACT FROM AUTHOR]