Abstract: The present invention discloses a thermal protection and warning method and system based on junction temperature prediction for a power device of an offshore wind power converter. The method includes: calculating a thermal resistance and a thermal capacitance corresponding to each layer inside the power device, and establishing a corresponding Cauer thermal network model; calculating power consumption at n future moments according to state variables at the n future moments corresponding to a minimized cost function, that is, calculating a variation trajectory of a heat flux parameter; calculating a variation trajectory of a junction temperature of the power device according to the Cauer thermal network model and the variation trajectory of the heat flux parameter; and comparing the calculated variation trajectory of the junction temperature with a warning temperature, and determining a current operating state of the power device.

Abstract: A predictive control method of a grid-connected converter based on a structurally adaptive extended state observer (ESO) is provided. The method includes: obtaining data of a grid current and a grid voltage and converting the data to data in a dq coordinate system; calculating a selected voltage vector based on a voltage in the dq coordinate system; adaptively inputting the current in the dq coordinate system to a parallel ESO, a cascade ESO, or a hybrid cascade-parallel ESO, so as to obtain a current predicted current value and estimated total disturbance; carrying out a two-step grid current prediction based on the current predicted current value, the estimated total disturbance and the selected voltage vector; and taking minimizing a cost function as a control target, so as to obtain an optimal voltage vector based on a two-step grid current prediction result, and carrying out switching control of the grid-connected converter.

Abstract: A surface-confined aqueous reversible addition-fragmentation chain transfer (SCARAFT) polymerization method was developed to coat capillaries for use in capillary zone electrophoresis (CZE). This coating produced an electroosmotic an order of magnitude lower than that of commercial linear polyacrylamide (LPA)-coated capillaries. Coated capillaries were evaluated for bottom-up proteomic analysis using CZE. The very low electroosmotic mobility results in a 200 min separation and improved single-shot analysis. Various types of coatings were prepared by simply changing the functional vinyl monomers in the polymerization mixture.

Abstract: The present invention discloses a thermal protection and warning method and system based on junction temperature prediction for a power device of an offshore wind power converter. The method includes: calculating a thermal resistance and a thermal capacitance corresponding to each layer inside the power device, and establishing a corresponding Cauer thermal network model; calculating power consumption at n future moments according to state variables at the n future moments corresponding to a minimized cost function, that is, calculating a variation trajectory of a heat flux parameter; calculating a variation trajectory of a junction temperature of the power device according to the Cauer thermal network model and the variation trajectory of the heat flux parameter; and comparing the calculated variation trajectory of the junction temperature with a warning temperature, and determining a current operating state of the power device.

Abstract: An electrokinetically pumped sheath flow nanospray interface for capillary electrophoresis coupled to negative mode electrospray mass spectrometer is described. At this interface, application of an electric field generates electro-osmotic flow at the interior of a glass emitter having an orifice. Electroosmotic flow pumps liquid around the distal tip of the separation capillary, ensheathing analyte into the electrospray electrolyte. In negative ion mode, negative potential applied to an untreated emitter drives sheath flow away from the emitter orifice, decreasing the stability and efficiency of the spray. In contrast, when the interior of the electrospray emitter is grafted with aminoalkylsilanes, the amines have a positive charge, which reverses electroosmosis and generates stable sheath flow to the emitter orifice under negative potential. Limits of detection were about 150 to 900 attomoles injected.

Abstract: An electrokinetically pumped sheath flow nanospray interface for capillary electrophoresis coupled to negative mode electrospray mass spectrometer is described. At this interface, application of an electric field generates electro-osmotic flow at the interior of a glass emitter having an orifice. Electroosmotic flow pumps liquid around the distal tip of the separation capillary, ensheathing analyte into the electrospray electrolyte. In negative ion mode, negative potential applied to an untreated emitter drives sheath flow away from the emitter orifice, decreasing the stability and efficiency of the spray. In contrast, when the interior of the electrospray emitter is grafted with aminoalkylsilanes, the amines have a positive charge, which reverses electroosmosis and generates stable sheath flow to the emitter orifice under negative potential. Limits of detection were about 150 to 900 attomoles injected.

Abstract: A surface-confined aqueous reversible addition-fragmentation chain transfer (SCARAFT) polymerization method was developed to coat capillaries for use in capillary zone electrophoresis (CZE). This coating produced an electroosmotic an order of magnitude lower than that of commercial linear polyacrylamide (LPA)-coated capillaries. Coated capillaries were evaluated for bottom-up proteomic analysis using CZE. The very low electroosmotic mobility results in a 200 min separation and improved single-shot analysis. Various types of coatings were prepared by simply changing the functional vinyl monomers in the polymerization mixture.