摘要:
A superconducting high-field magnet coil system comprising several radially nested main coil sections (1, 2, 3, 4, 5) which are connected to each other in series in such a fashion that currents of the same direction flow through them during operation, wherein a first main coil section (EHS) is disposed radially further inward than a second main coil section (ZHS) and at least one intermediate main coil section (ZW) is disposed radially between the first and the second main coil section (EHS, ZHS), and with a superconducting switch (11) via which all main coil sections (1, 2, 3, 4, 5) can be superconductingly short-circuited in series, is characterized in that the first main coil section (EHS) and the second main coil section (ZHS) are directly successively series-connected and the first main coil section (EHS) and the second main coil section (ZHS) are bridged by a common quench protection element, which does not bridge the at least one intermediate main coil section (ZW). The magnet coil system realizes quench protection for selectively preventing excess currents in magnet coil areas in which the excessive mechanical force load associated with an excess current would damage the superconductor.
摘要:
A superconducting high-field magnet coil system comprising several radially nested main coil sections (1, 2, 3, 4, 5) which are connected to each other in series in such a fashion that currents of the same direction flow through them during operation, wherein a first main coil section (EHS) is disposed radially further inward than a second main coil section (ZHS) and at least one intermediate main coil section (ZW) is disposed radially between the first and the second main coil section (EHS, ZHS), and with a superconducting switch (11) via which all main coil sections (1, 2, 3, 4, 5) can be superconductingly short-circuited in series, is characterized in that the first main coil section (EHS) and the second main coil section (ZHS) are directly successively series-connected and the first main coil section (EHS) and the second main coil section (ZHS) are bridged by a common quench protection element, which does not bridge the at least one intermediate main coil section (ZW). The magnet coil system realizes quench protection for selectively preventing excess currents in magnet coil areas in which the excessive mechanical force load associated with an excess current would damage the superconductor.
摘要:
In an arrangement for adjusting the spatial dependence of a magnetic field in a working volume of a main field magnet (19) by means of ferromagnetic field shaping elements (16), the field shaping elements (16) are formed from foils (1, 5, 7, 8) and/or sheet metals (10) having openings (2, 3) whose shape, position and size are selected such that the shape and the amount of the remaining ferromagnetic material produces a desired spatial dependence of the magnetic field in the working volume of the main field magnet for appropriate positioning of the foils (1, 5, 7, 8) and/or sheet metals (10) relative to the working volume of the main field magnet.
摘要:
A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), a ferromagnetic field formation device (3; 18) and a ferromagnetic shielding body (AK), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1) and the ferromagnetic shielding device (AK) surrounds the main field coil (1) and the shielding coil (2) in a radial and axial direction, the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2) being smaller than the axial extent Lhaupt of the main field coil (1), wherein the axial magnetic field profile (5) generated by the main field coil (1) and the shielding coil (2) during operation has a minimum of the field strength along the axis (z-axis) in the center (4a) and a maximum of the field strength on each side of the center (4a), and wherein the axial magnetic field profile (6) generated by the ferromagnetic field formation device (3; 18) and the ferromagnetic shielding body (AK) during operation has a maximum of the field strength along the axis (z-axis) in the center (4a) and a minimum of the field strength on each side of the center (4a). The magnet configuration in accordance with the invention has a very simple structure.
摘要:
A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), and a ferromagnetic field formation device (3; 18), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1), the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2) being smaller than the axial extent Lhaupt of the main field coil (1), wherein the axial magnetic field profile (5) generated by the main field coil (1) and the shielding coil (2) during operation has a minimum of the field strength along the axis (z-axis) in the center (4a) and a maximum of the field strength on each side of the center (4a), and wherein the axial magnetic field profile (6) generated by the ferromagnetic field formation device (3; 18) during operation has a maximum of the field strength along the axis (z-axis) in the center (4a) and a minimum of the field strength on each side of the center (4a). The magnet configuration in accordance with the invention has a very simple structure.
摘要:
A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), a ferromagnetic field formation device (3; 18) and a ferromagnetic shielding body (AK), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1) and the ferromagnetic shielding device (AK) surrounds the main field coil (1) and the shielding coil (2) in a radial and axial direction, the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2) being smaller than the axial extent Lhaupt of the main field coil (1), wherein the axial magnetic field profile (5) generated by the main field coil (1) and the shielding coil (2) during operation has a minimum of the field strength along the axis (z-axis) in the center (4a) and a maximum of the field strength on each side of the center (4a), and wherein the axial magnetic field profile (6) generated by the ferromagnetic field formation device (3; 18) and the ferromagnetic shielding body (AK) during operation has a maximum of the field strength along the axis (z-axis) in the center (4a) and a minimum of the field strength on each side of the center (4a). The magnet configuration in accordance with the invention has a very simple structure.
摘要:
An actively shielded superconducting magnet configuration (M1; M2; M3; 14) for generating a homogeneous magnetic field B0 in a volume under investigation (4b) has a radially inner superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z axis) and a coaxial radially outer superconducting shielding coil (2) which is operated in an opposite direction. The magnet configuration consists of the main field coil, the shielding coil and a ferromagnetic field-shaping device (3; 18), wherein the ferromagnetic field-shaping device is disposed radially inside the main field coil. The main field coil consists of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are operated in the same direction. An extension Labs of the shielding coil in the axial direction is smaller than the extension Lhaupt of the main field coil in the axial direction. 2 z 2 B H + A ( z ) z = 0 ≤ 0 applies for the axial magnetic field profile BH+A(z) generated by the main field coil and the shielding coil during operation along the z-axis in the center at z=0 and 2 z 2 B F ( z ) z = 0 ≥ 0 applies for the axial magnetic field profile BF(z) generated by the ferromagnetic field-shaping device (3; 18) during operation along the z-axis in the center at z=0, wherein the z-axis is oriented in a positive direction of the B0-field. An actively shielded superconducting magnet configuration of considerably simplified structure is thereby provided with a homogeneous and particularly high magnetic field B0 in the volume under investigation.
摘要:
An actively shielded superconducting magnet configuration (M1; M2; M3; 14) for generating a homogeneous magnetic field B0 in a volume under investigation (4b) has a radially inner superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z axis) and a coaxial radially outer superconducting shielding coil (2) which is operated in an opposite direction. The magnet configuration consists of the main field coil, the shielding coil and a ferromagnetic field-shaping device (3; 18), wherein the ferromagnetic field-shaping device is disposed radially inside the main field coil. The main field coil consists of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are operated in the same direction. An extension Labs of the shielding coil in the axial direction is smaller than the extension Lhaupt of the main field coil in the axial direction. ⅆ 2 ⅆ z 2 B H + A ( z ) ❘ z = 0 ≤ 0 applies for the axial magnetic field profile BH+A(z) generated by the main field coil and the shielding coil during operation along the z-axis in the center at z=0 and ⅆ 2 ⅆ z 2 B F ( z ) ❘ z = 0 ≥ 0 applies for the axial magnetic field profile BF(z) generated by the ferromagnetic field-shaping device (3; 18) during operation along the z-axis in the center at z=0, wherein the z-axis is oriented in a positive direction of the B0-field. An actively shielded superconducting magnet configuration of considerably simplified structure is thereby provided with a homogeneous and particularly high magnetic field B0 in the volume under investigation.
摘要:
A superconducting magnet configuration (4; 14) for generating a homogeneous magnetic field B0 in an examination volume (4b), has an interior radial superconducting main field coil (1) which is disposed rotationally symmetrically about an axis (z-axis) and an oppositely driven coaxial radially exterior superconducting shielding coil (2) is characterized in that the magnet configuration (4; 14) consists of the main field coil (1), the shielding coil (2), and a ferromagnetic field formation device (3; 18), wherein the ferromagnetic field formation device (3; 18) is located at the radially inside of the main field coil (1), the main field coil (1) consisting of an unstructured solenoid coil or of several radially nested unstructured solenoid coils (15, 16) which are driven in the same direction, the axial extent Labs of the shielding coil (2) being smaller than the axial extent Lhaupt of the main field coil (1), wherein the axial magnetic field profile (5) generated by the main field coil (1) and the shielding coil (2) during operation has a minimum of the field strength along the axis (z-axis) in the center (4a) and a maximum of the field strength on each side of the center (4a), and wherein the axial magnetic field profile (6) generated by the ferromagnetic field formation device (3; 18) during operation has a maximum of the field strength along the axis (z-axis) in the center (4a) and a minimum of the field strength on each side of the center (4a). The magnet configuration in accordance with the invention has a very simple structure.
摘要:
A magnet coil arrangement comprising an actively shielded superconducting primary circuit (21) comprising first and second magnet windings (1,2,3 and 4,5), and being wound e.g. in winding chambers (7,8,9 and 10,11) in a supporting body (6a,6b) for generating a strong magnetic field in a working volume with a small magnetic stray field and a short circuited secondary circuit (22) which is inductively coupled with the primary circuit (21) and contains third and fourth magnet windings (13,14,15 and 16,17) is characterized in that the magnet windings (13,14,15 and 16,17) of the secondary circuit (22) form an actively shielded magnet coil. This permits a simple and robust coil protection for actively shielded superconducting magnets during a quench wherein the superconducting magnet windings are reliably relieved and the magnetic stray field of the entire arrangement remains small.