Abstract: This grain-oriented electrical steel sheet is characterized in that the base steel sheet has a chemical composition containing, in mass %, Si:2.5-4.5%, Mn:0.01-1.00%, N:?0.01%, C:?0.01%, sol.A1:0.01%, S:?0.01%, Se:?0.01%, P:0.00-0.05%, Sb:0.00-0.50%, Sn:0.00-0.30%, Cr:0.00-0.50%, Cu:0.00-0.50%, Ni:0.00-0.50%, and Bi:0.0000-0.0100%, with the remainder including Fe and impurities, the magnetic flux density B8 in the rolling direction of the sheet is ?1.93 T, a deformed region extending over the entire width of the sheet is periodically formed at an interval L of 3-30 mm, in a direction intersecting the rolling direction, this region has a width W of 0.2-30.6 mm, a protrusion having a maximum height Dprotrusion of 1-5 m is formed on one surface of this region, and a recessed part having a maximum depth Drecess of 1-4 ?m is formed on the opposite surface.

Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When the iron oxide layer is analyzed by a fourier transform infrared spectroscopy, an absorbance A650 at 650 cm?1 and an absorbance A1250 at 1250 cm?1 satisfy 0.2?A650/A1250?5.0. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.

Abstract: The grain-oriented electrical steel sheet is a grain-oriented electrical steel sheet which does not have an inorganic coating containing forsterite as a main component, including a base steel sheet having a predetermined chemical component, a silicon-containing oxide layer provided on the base steel sheet, an iron-based oxide layer provided on the silicon-containing oxide layer, and a tension-insulation coating provided on the iron-based oxide layer, having a thickness of 1 to 3 ?m, and containing phosphate and colloidal silica as main components. When elemental analysis is performed from a surface of the tension-insulation coating in a sheet thickness direction by glow discharge optical emission spectrometry, predetermined requirements are satisfied.

Abstract: A motor control apparatus includes: a motor; an inverter circuit configured to drive the motor; a first wiring connecting the motor and the inverter circuit; a second wiring connecting the motor and the inverter circuit; a first sensor configured to detect a first current flowing through the first wiring; a second sensor configured to detect a second current flowing through the second wiring; and a dynamic braking circuit, and the dynamic braking circuit is connected between the first sensor and the motor and between the second sensor and the inverter circuit.

Abstract: A grain oriented electrical steel sheet includes: by mass %, 0.010% or less of C; 2.50 to 4.00% of Si; 0.010% or less of acid soluble Al; 0.012% or less of N; 1.00% or less of Mn; 0.020% or less of S; and a balance comprising Fe and impurities, and has a tension-insulation coating at steel sheet surface and a SiO2 intermediate oxide film layer with an average thickness of 1.0 nm to 1.0 ?m at an interface between the tension-insulation coating and the steel sheet surface. In the grain oriented electrical steel, when a surface of the intermediate oxide film layer is analyzed by an infrared reflection spectroscopy, a peak intensity IA at 1250 cm?1 and a peak intensity IB at 1200 cm?1 satisfy IB/IA?0.010.

Abstract: Grain-oriented electrical steel sheet excellent in magnetic properties and excellent in adhesion of a primary coating to the steel sheet is provided. The grain-oriented electrical steel sheet is provided with a base steel sheet having a chemical composition containing C: 0.005% or less, Si: 2.5 to 4.5%, Mn: 0.050 to 1.000%, a total of S and Se: 0.005% or less, sol. Al: 0.005% or less, and N: 0.005% or less and having a balance of Fe and impurities and a primary coating having Mg2 SiO4 as a main constituent formed on a surface of the base steel sheet. A peak position of Al emission intensity obtained when conducting elemental analysis by glow discharge spectrometry from a surface of the primary coating in a thickness direction is present in a range of 2.0 to 12.0 ?m from a surface of the primary coating to the thickness direction. A sum of perimeters of the Al oxides at the peak position of Al emission intensity is 0.20 to 1.00 ?m/?m2, and a number density of Al oxides is 0.02 to 0.20/?m2.

Abstract: Grain-oriented electrical steel sheet and its method of manufacture are provided. The method includes a process of heating to 1280° C. or more and hot rolling a slab containing, by mass %, Bi and a predetermined composition of constituents and having a balance of Fe and impurities to obtain hot rolled steel sheet. After hot rolling annealing, the hot rolled steel sheet is cold rolled one time or more with process annealing performed interposed so as to obtain cold rolled steel sheet, followed by a process of rapidly heating then decarburization annealing the steel sheet, a process of coating the surface of the cold rolled steel sheet after decarburization annealing with an annealing separator comprising sulfates or sulfides and having MgO as its main constituent, then performing finish annealing, a process of performing strictly controlled finish annealing, and a process of coating an insulating coating, then performing flattening annealing.

Abstract: A grain-oriented electrical steel sheet comprises a base steel sheet and a glass coating that is formed on the surface of the base steel sheet, and is characterized in that: the base steel sheet contains as chemical components, in mass %, 0.010% or less of C, from 2.00% to 4.00% of Si, from 0.05% to 1.00% of Mn, from 0.010% to 0.065% of Al, 0.004% or less of N and 0.010% or less of S, with the balance of Fe and impurities, wherein the oxygen concentration in the glass coating and the base steel sheet is 2,500 ppm or less; and if IAl_1 is the first peak intensity of Al and IAl_2 is the second peak intensity of Al in the concentration profile of Al, the relationship of mathematical formula (1) IAl_1<IAl_2 is satisfied.

Abstract: An input power monitoring circuit includes a rectifier circuit, a divided voltage generator circuit, a divided voltage comparator circuit, a switching circuit, and a computing device. The divided voltage comparator circuit is configured in such a manner that polarity of an output signal that is outputted from a first comparator upon a first rectified divided voltage exceeding a first comparison voltage is opposite to polarity of an output signal that is outputted from a second comparator upon a second rectified divided voltage exceeding a second comparison voltage. Output terminals of the first and second comparators are connected to each other. A connection point between the output terminals of the first and second comparators is connected to an input terminal of the switching circuit. The computing device measures frequency of a pulse signal outputted from the switching circuit, and determines the voltage state of input power based on the measured frequency.

Abstract: This grain-oriented electrical steel sheet includes: a base steel sheet; and an insulating coating formed on a surface of the base steel sheet, in which the insulating coating includes an intermediate layer formed on a base steel sheet side and containing a crystalline metal phosphate, and a tension coating layer formed on a surface side of the insulating coating, the surface of the base steel sheet has an etch pit structure, an average thickness of the intermediate layer is 0.2 to 10.0 ?m, an average thickness of the insulating coating is 2.0 to 10.0 ?m, the tension coating layer contains a metal phosphate and silica, and an amount of the silica in the tension coating layer is 20 to 60 mass %.

Abstract: This grain-oriented electrical steel sheet includes: a base steel sheet; and an insulating coating formed on a surface of the base steel sheet, in which the insulating coating includes an intermediate layer formed on a base steel sheet side and containing a crystalline metal phosphate, and a tension coating layer formed on a surface side of the insulating coating, an average thickness of the intermediate layer is 0.3 to 10.0 ?m, an average thickness of the insulating coating is 2.0 to 10.0 ?m, the crystalline metal phosphate of the intermediate layer is one or two or more of zinc phosphate, manganese phosphate, iron phosphate, and zinc calcium phosphate, the tension coating layer contains a metal phosphate and silica, and an amount of the silica in the tension coating layer is 20 to 60 mass %.

Abstract: This grain-oriented electrical steel sheet includes a base steel sheet, a glass coating formed on the base steel sheet, and a tension-applied insulation coating formed on the glass coating, in which, in the base steel sheet, a plurality of linear strain regions that extend continuously or intermittently in a direction intersecting with a rolling direction are present, the plurality of linear strain regions are each 210 ?m or less in width in the rolling direction, the plurality of linear strain regions are parallel to each other, intervals of linear strain regions adjacent to each other in the rolling direction are 10 mm or less, and magnetostriction ?0-pb in a unit of ?m/m when the grain-oriented electrical steel sheet is excited up to 1.7 T and magnetostriction ?0-pa in a unit of ?m/m when the grain-oriented electrical steel sheet is heat-treated at 800° C. for 4 hours and then excited up to 1.7 T satisfy 0.02??0-pb??0-pa?0.20.

Abstract: This grain-oriented electrical steel sheet includes a base steel sheet having a predetermined chemical composition, a glass coating formed on the base steel sheet, and a tension-applied insulation coating formed on the glass coating, on a front surface of the base steel sheet, a plurality of linear strains that extend continuously or intermittently in a direction intersecting with a rolling direction are present, intervals p in the rolling direction of the plurality of linear strains adjacent to each other are 3.0 to 9.0 mm, widths of the linear strains are 10 to 250 ?m, and, in an X-ray topographic spectrum in a range of 1.50 mm in the rolling direction that is obtained from an X-ray topographic image of the front surface and includes the linear strain at a center, a full width at half maximum of a peak of the X-ray topographic spectrum including a maximum value of a spectral intensity is 0.02 mm or more and 0.10 mm or less.

Abstract: A grain-oriented electrical steel sheet is a grain-oriented electrical steel sheet which does not have an inorganic coating containing forsterite as a main component and which includes: a base steel sheet containing a prescribed chemical component; a silicon-containing oxide layer provided on the base steel sheet; an iron-based oxide layer provided on the silicon-containing oxide layer; and a tension-insulation coating provided on the iron-based oxide layer, having a thickness of 1 to 3 ?m, and containing phosphate and colloidal silica as main components. When the tension-insulation coating undergoes elemental analysis using a glow discharge optical emission spectrometry in a sheet thickness direction from a surface of the tension-insulation coating, a peak Si emission intensity satisfies a prescribed requirement.

Abstract: This grain-oriented electrical steel sheet includes: a base steel sheet; and an insulating coating formed on a surface of the base steel sheet, in which the base steel sheet includes an iron-based oxide layer containing an iron-based oxide on an insulating coating side, the insulating coating includes an intermediate layer formed on a base steel sheet side and containing a crystalline metal phosphate, and a tension coating layer formed on a surface side of the insulating coating, an average thickness of the iron-based oxide layer is 0.10 to 1.50 ?m, an average thickness of the intermediate layer is 0.3 to 10.0 ?m, an average thickness of the insulating coating is 2.0 to 10.0 ?m, the crystalline metal phosphate of the intermediate layer is one or two or more of zinc phosphate, manganese phosphate, iron phosphate, and zinc calcium phosphate, the tension coating layer contains a metal phosphate and silica, and an amount of the silica in the tension coating layer is 20 to 60 mass %.

Abstract: This grain-oriented electrical steel sheet includes a base steel sheet, a glass coating formed on the base steel sheet, and a tension-applied insulation coating formed on the glass coating, in the base steel sheet, a plurality of linear strains that extend continuously or intermittently in a direction intersecting with a rolling direction are present, and intervals in the rolling direction of the plurality of linear strains adjacent to each other are 10 mm or less, in a region where the strains are present, a closure domain is present, a length d of the closure domain in a sheet thickness direction from a surface of the base steel sheet is 30 to 60 ?m, a length w in the rolling direction is 200 ?m or less, and a ratio mid of a depth m from the surface of the base steel sheet where a compressive strain in the rolling direction present in the closure domain exhibits a maximum value to the length d is in a range of more than 0.30 and less than 0.90.

Abstract: The grain-oriented electrical steel sheet according to the present embodiment is a grain-oriented electrical steel sheet having a base steel sheet (1), an intermediate layer (4) disposed to be in contact with the base steel sheet (1), and an insulation coating (3) disposed to be in contact with the intermediate layer (4). The grain-oriented electrical steel sheet according to the present embodiment includes a surface of the base steel sheet (1) having a strain region (D) which extends in a direction intersecting a rolling direction of the base steel sheet (1), and a crystalline phosphorus oxide M2P4O13 present in the insulation coating (3) on the strain region (D) in a cross-sectional view of a surface parallel to the rolling direction and a sheet thickness direction of the base steel sheet (1). (M means at least one or both of Fe and Cr.

Abstract: A grain oriented electrical steel sheet includes a base steel sheet, a glass film, and a tension-insulation coating. When a glow discharge emission spectroscopy is conducted from a surface of the glass film toward a depth direction, an analysis starting time Ts, a time TAlp at which Al shows a maximum emission intensity, an Al emission intensity F(TAlp) at the TAlp, a time TSip at which Si shows a maximum emission intensity, and an Al emission intensity F(TSip) at the TSip satisfy 0.05?F(TSip)/F(TAlp)?0.50 and 2.0?(TAlp?Ts)/(TSip?Ts)?5.0.

Abstract: A grain oriented electrical steel sheet includes a base steel sheet, an oxide layer, and a tension-insulation coating. When a glow discharge spectroscopy is conducted in a region from a surface of the tension-insulation coating to an inside of the base steel sheet, a sputtering time Fe0.5 at which a Fe emission intensity becomes 0.5 times as compared with a saturation value thereof and a sputtering time Fe0.05 at which a Fe emission intensity becomes 0.05 times as compared with the saturation value satisfy (Fe0.5?Fe0.05)/Fe0.5?0.35. A maximal point of a Cr emission intensity is included between the Fe0.05 and the Fesat. Moreover, a magnetic flux density B8 in a rolling direction of the grain oriented electrical steel sheet is 1.90 T or more.

Abstract: Provided is a production method for a grain-oriented electrical steel sheet that is thin and has excellent magnetic characteristics. An embodiment of the present invention provides a production method that is for a grain-oriented electrical steel sheet and that comprises: a hot rolling step; an optional hot-rolled sheet-annealing step; an acid-washing step; a cold rolling step; a primary recrystallization-annealing step; a finishing-annealing step; and a planarization-annealing step. In the acid-washing step, an acid-washing solution containing 0.0001-5.00 g/L of Cu is used. The thickness of a cold-rolled steel sheet is 0.15-0.23 mm. The average temperature increase rate in the temperature range of 30-400° C. in a temperature increase process in the primary recrystallization step is more than 50° C./sec but not more than 1000° C./sec.