Parameter estimation for condition monitoring of PMSM stator winding and rotor permanent magnets

Winding resistance and rotor flux linkage are important to controller design and condition monitoring of a surface-mounted permanent-magnet synchronous machine (PMSM) system. In this paper, an online method for simultaneously estimating the winding resistance and rotor flux linkage of a PMSM is proposed, which is suitable for application under constant load torque. It is based on a proposed full-rank reference/variable model. Under constant load torque, a short pulse of id 0 is transiently injected into the d-axis current, and two sets of machine rotor speeds, currents, and voltages corresponding to id = 0 and id 0 are then measured for estimation. Since the torque is kept almost constant during the transient injection, owing to the moment of system inertia and negligible reluctance torque, the variation of rotor flux linkage due to injected id 0 can be taken into account by using the equation of constant torque without measuring the load torque and is then associated with the two sets of machine equations for simultaneously estimating the winding resistance and rotor flux linkage. Furthermore, the proposed method does not need the values of the $dq$-axis inductances, while the influence from the nonideal voltage measurement, which will cause an ill-conditioned problem in the estimation, has been taken into account and solved by error analysis. This method is finally verified on two prototype PMSMs and shows good performance. © 1982-2012 IEEE

Parameter estimation for condition monitoring of PMSM stator winding and rotor permanent magnets

Winding resistance and rotor flux linkage are important to controller design and condition monitoring of a surface-mounted permanent-magnet synchronous machine (PMSM) system. In this paper, an online method for simultaneously estimating the winding resistance and rotor flux linkage of a PMSM is proposed, which is suitable for application under constant load torque. It is based on a proposed full-rank reference/variable model. Under constant load torque, a short pulse of id 0 is transiently injected into the d-axis current, and two sets of machine rotor speeds, currents, and voltages corresponding to id = 0 and id 0 are then measured for estimation. Since the torque is kept almost constant during the transient injection, owing to the moment of system inertia and negligible reluctance torque, the variation of rotor flux linkage due to injected id 0 can be taken into account by using the equation of constant torque without measuring the load torque and is then associated with the two sets of machine equations for simultaneously estimating the winding resistance and rotor flux linkage. Furthermore, the proposed method does not need the values of the $dq$-axis inductances, while the influence from the nonideal voltage measurement, which will cause an ill-conditioned problem in the estimation, has been taken into account and solved by error analysis. This method is finally verified on two prototype PMSMs and shows good performance. © 1982-2012 IEEE

Synthesis and Properties of a Novel Structural Binder Utilizing the Chemistry of Iron Carbonation

This paper explores, for the first time, the possibility of carbonating waste metallic iron powder to develop sustainable binder systems for concrete. The fundamental premise of this work is that metallic iron will react with aqueous CO₂ under controlled conditions to form complex iron carbonates which have binding capabilities. Chosen additives containing silica and alumina are added to facilitate iron dissolution and to obtain beneficial rheological and later-age properties. Water is generally only a medium for mass transfer in these systems thereby making the common reaction schemes in portland cement concretes inapplicable. The compressive and flexural strengths of the chosen iron-based binder systems increase with carbonation duration and the specimens carbonated for 4 days exhibit mechanical properties that are comparable to those of companion ordinary portland cement systems that are most commonly used as the binder in building and infrastructural construction. The influence of the additives, carbonation duration, and the air curing duration after carbonation are explored in detail. Thermogravimetric analysis demonstrate the presence of an organic carbonate complex (the dissolution agent used to dissolve iron is organic), the amount of which increases with carbonation duration. Thermal analysis also confirms the participation of some amount of limestone powder in the reaction product formation. The viability of this binder type for concrete applications is proved in this study

Heavy Alkali Metal Tris(trimethylsilyl)silanides: A Synthetic and Structural Study

Treatment of lithium tris(trimethylsilyl)silanide, Li(THF)3Si(SiMe3)3, with heavier alkali metal tert-butoxides yielded the alkali metal silanides MSi(SiMe3)3 (M = K, Rb, or Cs) in a simple, high-yielding, one-step procedure. Separation of the two solid reaction products was achieved by addition of crown ether, which also determines the formation of contact or separated ion pairs in the solid state. Here we report the synthesis and structural characterization of the contact ion K(18-crown-6)Si(SiMe3)3, 2, in addition to the separated [K(12-crown-4)2][Si(SiMe3)3], 1, [Rb(15-crown-5)2][Si(SiMe3)3], 3, and [Cs(18-crown-6)2][Si(SiMe3)3], 5. [Rb(18-crown-6)2][Si(SiMe3)3][Rb(18-crown-6)Si(SiMe3)3]2, 4, is a rare example where both contact and separated ions are observed in the solid state. The investigation of synthetic routes toward the target compounds also examined the previously published metalation of Si(SiMe3)4 with potassium tert-butoxide. This route proved to be temperamental:  depending on reaction conditions and solvent systems, either adducts between product and unreacted starting material, namely, [{K(THF)Si(SiMe3)3}{KOtBu}3], 6, or the target compound KSi(SiMe3)3 was isolated. All compounds were characterized by X-ray crystallography and NMR spectroscopy

Using genetic probes to identify gadoid eggs in surveys to monitor the Irish Sea cod stock under the EU recovery program

No abstracts are to be cited without prior reference to the author.Early stage eggs of cod (Gadus morhua L.) are impossible to visually differentiate from those of haddock (Melanogrammus aeglefinus L.) or whiting (Merlangius merlangus L.). This project uses Taqman species specific probes in multiplex real-time PCR chemistry to distinguish between these three species as part of the Irish Sea egg production monitoring which aims to evaluate the status of the Irish Sea cod stock during the EU stock recovery program

Heavy Alkali Metal Tris(trimethylsilyl)silanides: A Synthetic and Structural Study

Treatment of lithium tris(trimethylsilyl)silanide, Li(THF)3Si(SiMe3)3, with heavier alkali metal tert-butoxides yielded the alkali metal silanides MSi(SiMe3)3 (M = K, Rb, or Cs) in a simple, high-yielding, one-step procedure. Separation of the two solid reaction products was achieved by addition of crown ether, which also determines the formation of contact or separated ion pairs in the solid state. Here we report the synthesis and structural characterization of the contact ion K(18-crown-6)Si(SiMe3)3, 2, in addition to the separated [K(12-crown-4)2][Si(SiMe3)3], 1, [Rb(15-crown-5)2][Si(SiMe3)3], 3, and [Cs(18-crown-6)2][Si(SiMe3)3], 5. [Rb(18-crown-6)2][Si(SiMe3)3][Rb(18-crown-6)Si(SiMe3)3]2, 4, is a rare example where both contact and separated ions are observed in the solid state. The investigation of synthetic routes toward the target compounds also examined the previously published metalation of Si(SiMe3)4 with potassium tert-butoxide. This route proved to be temperamental:  depending on reaction conditions and solvent systems, either adducts between product and unreacted starting material, namely, [{K(THF)Si(SiMe3)3}{KOtBu}3], 6, or the target compound KSi(SiMe3)3 was isolated. All compounds were characterized by X-ray crystallography and NMR spectroscopy

Heavy Alkali Metal Tris(trimethylsilyl)silanides: A Synthetic and Structural Study

Treatment of lithium tris(trimethylsilyl)silanide, Li(THF)3Si(SiMe3)3, with heavier alkali metal tert-butoxides yielded the alkali metal silanides MSi(SiMe3)3 (M = K, Rb, or Cs) in a simple, high-yielding, one-step procedure. Separation of the two solid reaction products was achieved by addition of crown ether, which also determines the formation of contact or separated ion pairs in the solid state. Here we report the synthesis and structural characterization of the contact ion K(18-crown-6)Si(SiMe3)3, 2, in addition to the separated [K(12-crown-4)2][Si(SiMe3)3], 1, [Rb(15-crown-5)2][Si(SiMe3)3], 3, and [Cs(18-crown-6)2][Si(SiMe3)3], 5. [Rb(18-crown-6)2][Si(SiMe3)3][Rb(18-crown-6)Si(SiMe3)3]2, 4, is a rare example where both contact and separated ions are observed in the solid state. The investigation of synthetic routes toward the target compounds also examined the previously published metalation of Si(SiMe3)4 with potassium tert-butoxide. This route proved to be temperamental:  depending on reaction conditions and solvent systems, either adducts between product and unreacted starting material, namely, [{K(THF)Si(SiMe3)3}{KOtBu}3], 6, or the target compound KSi(SiMe3)3 was isolated. All compounds were characterized by X-ray crystallography and NMR spectroscopy

Size and Emission Control of Wurtzite InP Nanocrystals Synthesized from Cu_3–<i>x</i>P by Cation Exchange

Phosphide-based nanocrystals (NCs), including InP and Cu3–xP, are relevant for applications in light-emitting devices and catalysis, yet their synthetic design is limited in terms of size range and homogeneity. We report the synthesis of uniform and size-controlled emissive wurtzite-phase InP NCs formed via cation exchange from Cu3–xP. First, size-controlled Cu3–xP NCs are synthesized by the formation of metallic Cu0 NCs and their phosphidation to Cu3–xP. By changing the ligands and precursor concentrations, the NC size is varied between 5 and 13 nm. Using cation exchange, InP NCs are then generated. As the surface of InP NCs is prone to oxidation and defects that decrease their emission, we performed a reaction with NOBF4. This yields InP NCs with resolved absorption features and efficient band-gap emission as a result of impurity removal and surface passivation. The effect of water, acid, and halides on the balance of NC etching and surface passivation is studied. With this approach, high-quality wurtzite InP NCs are obtained while the emission is tuned between 810 and 600 nm. The obtained NCs are potential building blocks for catalytic and optoelectronic applications

Luminescent Anisotropic Wurtzite InP Nanocrystals

Indium phosphide (InP) nanocrystals are emerging as an alternative to heavy metal containing nanocrystals for optoelectronic applications but lag behind in terms of synthetic control. Herein, luminescent wurtzite InP nanocrystals with narrow size distribution were synthesized via a cation exchange reaction from hexagonal Cu3P nanocrystals. A comprehensive surface treatment with NOBF4 was performed, which removes excess copper while generating stoichiometric In/P nanocrystals with fluoride surface passivation. The attained InP nanocrystals manifest a highly resolved absorption spectrum with a narrow emission line of 80 meV, and photoluminescence quantum yield of up to 40%. Optical anisotropy measurements on ensemble and single particle bases show the occurrence of polarized transitions directly mirroring the anisotropic wurtzite lattice, as also manifested from modeling of the quantum confined electronic levels. This shows a green synthesis path for achieving wurtzite InP nanocrystals with desired optoelectronic properties including color purity and light polarization with potential for diverse optoelectronic applications

MOESM2 of Sequencing of animal viruses: quality data assurance for NGS bioinformatics

Additional file 2. Primers used to Sanger sequence the vector containing the VHSV 23/75 full-length cDNA (p23–75). The nucleotide positions refer to the VSHV sequence under the GenBank acc. no. FN665788