CN112837890B - Asymmetric ship magnetic field vertical component compensation method - Google Patents

Asymmetric ship magnetic field vertical component compensation method Download PDF

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CN112837890B
CN112837890B CN202011608053.3A CN202011608053A CN112837890B CN 112837890 B CN112837890 B CN 112837890B CN 202011608053 A CN202011608053 A CN 202011608053A CN 112837890 B CN112837890 B CN 112837890B
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宋新昌
孙晓君
张炜
邵成
赵治平
唐宗勇
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710th Research Institute of CSIC
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F13/00—Apparatus or processes for magnetising or demagnetising
    • H01F13/006—Methods and devices for demagnetising of magnetic bodies, e.g. workpieces, sheet material
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract

The invention discloses a method for compensating vertical components of an asymmetric ship magnetic field, which decomposes the vertical magnetic field components of the asymmetric ship sailing in the same latitude area, and overcomes the defects that the decomposition of the traditional 'symmetric ship' hypothesis method causes: 1) Ziy and Zpy under the keel are equal to zero, and Ziy and Zpy under the port and starboard are opposite numbers; 2) The defects that Zpx under a keel and Zpx under a board are opposite in fore and aft and Zix and Zpx under a port and a starboard are equal are overcome, the magnetic field compensation method has the effects of being simple to operate, reasonable and credible in decomposition result, and finally improves the accuracy of magnetic field compensation.

Description

Asymmetric ship magnetic field vertical component compensation method
Technical Field
The invention belongs to the technical field of ship demagnetization, and particularly relates to a method for compensating a vertical component of a magnetic field of an asymmetric ship, which is suitable for decomposing the vertical component of the magnetic field of an unshaped asymmetric ship, a submarine and an underwater vehicle and compensating the magnetic field and has the characteristics of simple calculation and high calculation result precision.
Background
During degaussing, generally speaking, when the vertical component of the magnetic field of the ship is reduced, the horizontal component is correspondingly reduced. At present, in the degaussing service, the horizontal component of ships, submarines and underwater navigation bodies in seawater is difficult to orient and maintain the horizontal component. So there is a greater chance in practical applications to use the concept of vertical component. The perpendicular component of the magnetic field of the ship consists of three parts, namely a vertical component of a longitudinal magnetic field of the ship, a vertical component of a transverse magnetic field of the ship and a vertical component of a vertical magnetic field of the ship, wherein each part is synthesized by a fixed magnetic field and an induction magnetic field, and the vertical component of the magnetic field of the ship is shown in figure 1: the fixed magnetic field is constant and the induced magnetic field varies according to different course and location.
Disclosure of Invention
In view of this, the present invention provides a method for compensating the vertical component of the magnetic field of an asymmetric ship, so as to improve the compensation accuracy.
A method for compensating vertical components of an asymmetric ship magnetic field comprises the following steps:
the method comprises the steps of firstly, measuring to obtain the vertical component of an original magnetic field of a ship, and measuring the original magnetic field of the ship on four main courses of east, south, west and north of the ship under the same water depth; the asymmetric ship magnetic field vertical component Bz is decomposed into three parts on the whole, zp is a fixed magnetic field vertical component, zix is a longitudinal induction magnetic field vertical component, and the north course is Zix and the south course is-Zix; ziy is the vertical component of the transverse induction magnetic field, the east course is Ziy, and the west course is-Ziy;
step two, finding out the vertical components of the original magnetic fields below a port, a keel and a starboard at the same longitudinal distance upwards in the magnetic east navigation direction, respectively arranging the vertical components into a row according to the sequence from the ship bow to the ship stern, and the like:
magnetic east navigation:
Figure BDA0002870744610000011
Figure BDA0002870744610000012
Figure BDA0002870744610000013
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA0002870744610000021
perpendicular component, Z, representing the port magnetic east-navigation field p(z) Vertical component of fixed magnetic field, Z, of port iy(z) Representing a port-side transverse induced magnetic field component;
Figure BDA0002870744610000022
representing the vertical component, Z, of the keel magnetic east-navigation magnetic field p(l) Indication keelFixing the magnetic perpendicular component of the magnetic field, Z iy(l) Representing the transverse induction field component of the keel;
Figure BDA0002870744610000023
represents the vertical component of the starboard magnetic east-navigation field; z p(y) Represents the magnetic vertical component, Z, of the starboard fixed magnetic field iy(y) Representing the starboard transverse induced magnetic field component;
magnetic south course:
Figure BDA0002870744610000024
Figure BDA0002870744610000025
Figure BDA0002870744610000026
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA0002870744610000027
representing the vertical component of the port-side magnetic south course field, Z ix(z) Representing the vertical component of the port side longitudinally induced magnetic field,
Figure BDA00028707446100000219
representing the vertical component, Z, of the keel flux south course field ix(l) Showing the vertical component of the longitudinal induced magnetic field of the keel,
Figure BDA0002870744610000028
representing the vertical component of the starboard magnetic south course field, Z ix(y) Representing the starboard longitudinal induced magnetic field vertical component;
magnetic western navigation direction:
Figure BDA0002870744610000029
Figure BDA00028707446100000210
Figure BDA00028707446100000211
wherein the content of the first and second substances,
Figure BDA00028707446100000212
representing the vertical component of the port magnetic western-course field, Z iy(z) Representing the port side transverse induced magnetic field vertical component,
Figure BDA00028707446100000213
representing the vertical component, Z, of the magnetic field of the keel in the western direction iy(l) Showing the vertical component of the magnetic field induced transversely to the keel,
Figure BDA00028707446100000214
representing the vertical component of the starboard magnetic western-course field, Z iy(y) Representing the starboard transverse induced magnetic field vertical component;
magnetic north heading:
Figure BDA00028707446100000215
Figure BDA00028707446100000216
Figure BDA00028707446100000217
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA00028707446100000218
representing the vertical component, Z, of the port side magneto-north heading magnetic field ix(z) Indicating the longitudinal feeling of the portIn response to the perpendicular component of the magnetic field,
Figure BDA0002870744610000031
representing the vertical component, Z, of the keel flux north heading magnetic field ix(l) Showing the vertical component of the magnetic field induced longitudinally in the keel,
Figure BDA0002870744610000032
representing the vertical component of the starboard magneto-north heading field, Z ix(y) Represents the starboard longitudinal induced magnetic field vertical component;
step three, respectively calculating the vertical components of the fixed magnetic fields below the port, keel and starboard according to the formulas (1) to (12):
Figure BDA0002870744610000033
Figure BDA0002870744610000034
Figure BDA0002870744610000035
step four, solving the vertical components of the longitudinal induction magnetic field below the magnetic north heading port, keel and starboard respectively:
Figure BDA0002870744610000036
Figure BDA0002870744610000037
Figure BDA0002870744610000038
step five, respectively solving the vertical components of the transverse induction magnetic field below the magnetic east-navigation port, keel and starboard:
Figure BDA0002870744610000039
Figure BDA00028707446100000310
Figure BDA00028707446100000311
after the decomposition of the vertical component of the magnetic field of the ship is finished, the vertical component of the fixed magnetic field is compensated by comprehensively considering the X-direction winding, the Y-direction winding and the Z-direction winding in the ampere-turn adjusting process of the degaussing winding, the vertical component of the longitudinal induced magnetic field is compensated by the X-direction winding, and the vertical component of the transverse induced magnetic field is compensated by the Y-direction winding.
The invention has the following beneficial effects:
compared with the prior art, the method firstly decomposes the vertical magnetic field component of the asymmetric ship sailing in the same latitude area, and overcomes the defects that the conventional 'symmetric ship' is supposed to cause decomposition: 1) Ziy and Zpy under the keel are equal to zero, and Ziy and Zpy under the port and starboard are opposite numbers; 2) The defects that Zpx under a keel and Zpx under a board are opposite in fore and aft and Zix and Zpx under a port and a starboard are equal are overcome, the magnetic field compensation method has the effects of being simple to operate, reasonable and credible in decomposition result, and finally improves the accuracy of magnetic field compensation.
Drawings
FIG. 1 is a diagram of the vertical component composition of a magnetic field of a ship;
FIG. 2 is a component diagram of the vertical component of the magnetic field of an asymmetric ship according to an embodiment of the present invention;
FIG. 3 is a flow chart of a method for decomposing the vertical component of an asymmetric ship magnetic field.
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
A method for decomposing and compensating the vertical component of the magnetic field of an asymmetric ship comprises the following basic implementation processes:
the method comprises the steps of firstly, obtaining the vertical component of the original magnetic field of the ship through measurement, and measuring the original magnetic field of the ship on four main courses of east, south, west and north at the same water depth. Decomposing the vertical component Bz of the magnetic field of the asymmetric ship into three parts on the whole, wherein Zp is the vertical component of the fixed magnetic field, and Zix is the vertical component of the longitudinal induction magnetic field, and the north course is Zix and the south course is-Zix; ziy is the vertical component of the transverse induction magnetic field, east course is Ziy, west course is-Ziy, and the magnetization state of the ship can be known.
And step two, finding out the vertical components of the original magnetic fields below the port, the keel and the starboard at the same longitudinal distance in the magnetic east navigation direction, respectively arranging the vertical components into a row according to the sequence from the ship bow to the ship stern, and the like.
The magnetic field of the ship at different courses and different positions consists of four main courses of east, south, west and north (wherein E, S, W and N represent four main courses of east, south, west and north, z represents a port, l represents a keel, y represents a starboard, for example
Figure BDA0002870744610000041
Representing the vertical component, Z, of the port magnetic east-navigation field p(z) The vertical component of the magnetic field is fixed on the port, and the rest are analogized in turn.
Magnetic east navigation:
Figure BDA0002870744610000042
Figure BDA0002870744610000043
Figure BDA0002870744610000044
wherein Z is iy(z) Representing a port side transverse induced magnetic field component;
Figure BDA0002870744610000045
representing the vertical component, Z, of the keel magnetic east-navigation field p(l) Indicating the magnetic vertical component, Z, of the fixed magnetic field of the keel iy(l) Representing the transverse induction magnetic field component of the keel;
Figure BDA0002870744610000046
represents the vertical component of the starboard magnetic east-navigation magnetic field; z p(y) Represents the magnetic vertical component, Z, of the starboard fixed magnetic field iy(y) Representing the starboard transverse induced magnetic field component;
magnetic south course:
Figure BDA0002870744610000051
Figure BDA0002870744610000052
Figure BDA0002870744610000053
wherein the content of the first and second substances,
Figure BDA0002870744610000054
representing the vertical component, Z, of the port-side magnetic south-heading magnetic field ix(z) Representing the vertical component of the port side longitudinally induced magnetic field,
Figure BDA0002870744610000055
represents the vertical component, Z, of the keel magnetic south course magnetic field ix(l) Showing the vertical component of the longitudinal induced magnetic field of the keel,
Figure BDA0002870744610000056
representing the vertical component, Z, of the starboard magnetic south heading magnetic field ix(y) Representing the starboard longitudinal induced magnetic field vertical component;
magnetic western heading:
Figure BDA0002870744610000057
Figure BDA0002870744610000058
Figure BDA0002870744610000059
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA00028707446100000510
representing the vertical component of the port magnetic western-course field, Z iy(z) Representing the port side transverse induced magnetic field vertical component,
Figure BDA00028707446100000511
representing the vertical component, Z, of the keel magnetic west-direction magnetic field iy(l) Showing the vertical component of the magnetic field induced transversely to the keel,
Figure BDA00028707446100000512
representing the vertical component of the starboard magnetic western-course field, Z iy(y) Representing the starboard transverse induced magnetic field vertical component;
magnetic north heading:
Figure BDA00028707446100000513
Figure BDA00028707446100000514
Figure BDA00028707446100000515
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA00028707446100000516
representing the vertical component, Z, of the port side magneto-north heading magnetic field ix(z) Representing the vertical component of the port side longitudinally induced magnetic field,
Figure BDA00028707446100000517
representing the vertical component, Z, of the keel flux north heading magnetic field ix(l) Showing the vertical component of the longitudinal induced magnetic field of the keel,
Figure BDA00028707446100000518
representing the vertical component, Z, of the starboard magneto-north heading magnetic field ix(y) Showing the starboard longitudinal induced magnetic field vertical component.
Step three, respectively calculating the vertical components of the fixed magnetic fields below the port, keel and starboard according to the formulas (1) to (12):
Figure BDA0002870744610000061
Figure BDA0002870744610000062
Figure BDA0002870744610000063
step four, the vertical components of the longitudinal induction magnetic field under the magnetic north heading port, keel and starboard can be respectively obtained through the formulas (16) - (18):
Figure BDA0002870744610000064
Figure BDA0002870744610000065
Figure BDA0002870744610000066
step five, the vertical components of the magnetic transverse induction magnetic field under the port, keel and starboard of the magnetic east navigation direction can be respectively obtained through the formulas (19) to (21):
Figure BDA0002870744610000067
Figure BDA0002870744610000068
Figure BDA0002870744610000069
and step six, after the vertical component of the magnetic field of the ship is decomposed, comprehensively considering X-direction windings, Y-direction windings and Z-direction windings and simultaneously compensating Zp, compensating Zix by the X-direction windings and compensating Ziy by the Y-direction windings in the ampere-turn number adjustment process of the degaussing windings.
Examples
For example, the magnetic field measurement data of a fishing boat in the east, south, west and north main directions are shown in Table 1
TABLE 1 magnetic field measurement data of a fishing vessel in east, south, west and north main courses
Figure BDA00028707446100000610
Figure BDA0002870744610000071
Comparing the measured data of the vertical component Bz under the keels in the east and west shipping directions in the table 1, the values are found to be unequal, that is to say, ziy under the keels is not zero, if a 'symmetrical ship' is used for solving, a system error is introduced, and the optimal demagnetization effect cannot be achieved in the subsequent demagnetization winding ampere-turn number adjustment process. The decomposition results obtained by the method of this patent are shown in Table 2
TABLE 2 data decomposed by asymmetric ship magnetic field vertical component decomposition method for certain fishing vessel
Figure BDA0002870744610000072
Figure BDA0002870744610000081
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (1)

1. A method for compensating the vertical component of the magnetic field of an asymmetric ship is characterized by comprising the following steps:
the method comprises the steps of firstly, measuring to obtain the vertical component of an original magnetic field of a ship, and measuring the original magnetic field of the ship on four main courses of east, south, west and north of the ship under the same water depth; the asymmetric ship magnetic field vertical component Bz is generally decomposed into three parts, zp is a fixed magnetic field vertical component, zix is a longitudinal induction magnetic field vertical component, and the north course is Zix and the south course is-Zix; ziy is the vertical component of the transverse induction magnetic field, the east course is Ziy, and the west course is-Ziy;
step two, finding out the vertical components of the original magnetic fields below a port, a keel and a starboard at the same longitudinal distance upwards in the magnetic east navigation direction, respectively arranging the vertical components into a row according to the sequence from the ship bow to the ship stern, and the like:
in the second step, the method specifically comprises the following steps:
magnetic east navigation:
Figure FDA0003862843930000011
Figure FDA0003862843930000012
Figure FDA0003862843930000013
wherein the content of the first and second substances,
Figure FDA0003862843930000014
perpendicular component, Z, representing the port magnetic east-navigation field p(z) Vertical component of fixed magnetic field, Z, port iy(z) Representing a port side transverse induced magnetic field component;
Figure FDA0003862843930000015
representing the vertical component, Z, of the keel magnetic east-navigation field p(l) Represents the magnetic vertical component of the fixed magnetic field of the keel, Z iy(l) Representing the transverse induction field component of the keel;
Figure FDA0003862843930000016
represents the vertical component of the starboard magnetic east-navigation magnetic field; z p(y) Represents the magnetic vertical component, Z, of the starboard fixed magnetic field iy(y) Representing the starboard transverse induced magnetic field component;
magnetic south course:
Figure FDA0003862843930000017
Figure FDA0003862843930000018
Figure FDA0003862843930000019
wherein the content of the first and second substances,
Figure FDA00038628439300000110
representing the vertical component of the port-side magnetic south course field, Z ix(z) Representing the port side longitudinally induced magnetic field vertical component,
Figure FDA00038628439300000111
represents the vertical component, Z, of the keel magnetic south course magnetic field ix(l) Showing the vertical component of the longitudinal induced magnetic field of the keel,
Figure FDA00038628439300000112
representing the vertical component, Z, of the starboard magnetic south heading magnetic field ix(y) Represents the starboard longitudinal induced magnetic field vertical component;
magnetic western navigation direction:
Figure FDA00038628439300000113
Figure FDA0003862843930000021
Figure FDA0003862843930000022
wherein, the first and the second end of the pipe are connected with each other,
Figure FDA0003862843930000023
representing the vertical component of the port magnetic western-course field, Z iy(z) Representing the port side transverse induced magnetic field vertical component,
Figure FDA0003862843930000024
representing the vertical component, Z, of the keel magnetic west-direction magnetic field iy(l) Showing the vertical component of the magnetic field induced transversely in the keel,
Figure FDA0003862843930000025
representing the vertical component of the starboard magnetic western-course field, Z iy(y) Represents the starboard transverse induced magnetic field vertical component;
magnetic north heading:
Figure FDA0003862843930000026
Figure FDA0003862843930000027
Figure FDA0003862843930000028
wherein the content of the first and second substances,
Figure FDA0003862843930000029
representing the vertical component, Z, of the port side magneto-north heading magnetic field ix(z) Representing the port side longitudinally induced magnetic field vertical component,
Figure FDA00038628439300000210
representing the vertical component, Z, of the keel flux north heading magnetic field ix(l) Showing the vertical component of the longitudinal induced magnetic field of the keel,
Figure FDA00038628439300000211
representing the vertical component, Z, of the starboard magneto-north heading magnetic field ix(y) Represents the starboard longitudinal induced magnetic field vertical component;
step three, respectively calculating the vertical components of the fixed magnetic fields below the port, keel and starboard according to the formulas (1) to (12):
Figure FDA00038628439300000212
Figure FDA00038628439300000213
Figure FDA00038628439300000214
step four, solving the vertical components of the longitudinal induction magnetic field below the magnetic north heading port, keel and starboard respectively:
Figure FDA00038628439300000215
Figure FDA00038628439300000216
Figure FDA00038628439300000217
step five, respectively solving the vertical components of the transverse induction magnetic field below the magnetic east-navigation port, keel and starboard:
Figure FDA0003862843930000031
Figure FDA0003862843930000032
Figure FDA0003862843930000033
after the decomposition of the vertical component of the magnetic field of the ship is finished, the vertical component of the fixed magnetic field is compensated by comprehensively considering the X-direction winding, the Y-direction winding and the Z-direction winding in the ampere-turn adjusting process of the degaussing winding, the vertical component of the longitudinal induced magnetic field is compensated by the X-direction winding, and the vertical component of the transverse induced magnetic field is compensated by the Y-direction winding.
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