EP0249838A1 - Device for controlling a magnetic installation for self-protection - Google Patents

Abstract

The invention describes a process-controlled magnetic installation for self-protection which has an extensive, triaxial coil system consisting of current-carrying coils in the three orthogonal vessel axes for compensating for the magnetic proper field of the vessel dependent upon the earth's magnetic field at the location of the vessel and the vessel movement (course, rolling, etc.). A process control system is provided which has a digital data processor (9) to which a data bank (8) is allocated in which vessel-specific data from the initial measurement at the measuring point and location-specific data on the conditions of the earth's magnetism in the operational area of the vessel (geomagnetic data) are filed, to which measurement transducers on board the vessel (ship 1) are allocated for coil data, geographical location, course and inherent motion of the vessel, and which, on account of a predetermined sequence control (algorithms), controls the number of ampere turns in the compensation coils in such a way that optimum compensation is guaranteed. <IMAGE>

Description

The invention relates to a device for controlling a magnetic self-protection (MES) system of a vehicle, which has a large-area, three-axis coil system consisting of current-carrying coils in three orthogonal vehicle axes to compensate for the earth's magnetic field at the vehicle location and the vehicle's movement in the earth's magnetic field (course, roll, Etc.). dependent magnetic field of the vehicle.

Ships, boats and other vehicles of the Bundeswehr, but also merchant ships, are directly threatened by mines and torpedoes with magnetic sensors due to their own magnetic field (interference field), which overlaps and distorts the earth's field, or can be tracked down using magnetic sensors. For this reason, the vehicles to be protected are equipped with an MES system, which has the task of reducing the magnetic field and thus the hazard.

The magnetic self-field contains a so-called permanent component and an induced component, which is due to the permanent magnetization of the vehicle when driving in the earth's field, the size of which varies depending on the course and the position of the vehicle axles to the horizon.

Such MES systems are well described in the literature (e.g. Kosack and Wangerin, "Electrical engineering on merchant ships", Springer Verlag 1956, pages 255-257, Fig. 234). They have a large, three-axis coil system consisting of coils through which current flows in three orthogonal axes to compensate for the vehicle's own magnetic field.

Every vehicle equipped with an MES system first experiences a basic setting of the MES system (initial measurement) based on a so-called magnetic measurement, in which an optimal compensation value is achieved by setting suitable winding currents and suitable coil switching states (ampere-turn numbers).

However, the setting changes - apart from long-term changes that require a setting check at certain intervals - while driving. As a result of

- Dependence on latitude of the earth's magnetic field

- Course dependency of the induced portion generated by the horizontal component of the earth's magnetic field

- Dependence of the induced field on the position of the vehicle axles to the horizon

the MES system has a regulating device or a controller which adjusts the currents or, by switching windings, the ampere-turn numbers in the individual coils during driving so that the set compensation of the interference field is retained.

It is known to provide a manual latitude controller and a course compensation controller which can be operated both manually and automatically by the gyrocompass (German mine clearance regulation No. 16 "Magnetic protection of the mine clearance vehicles, 1946 in particular page 14/15).

In practice, however, the Gyro MES system is a manual control. Errors in the operation of the controllers are therefore only recognized by manual control. In addition, the eigenfield changes are not recorded in the known system. The known MES system can therefore no longer meet today's requirements with regard to the increased sensitivity of the detonators.

It is also known to use magnetic sensing elements (sensors) to detect changes in the ship and earth field (Kosack and Wangerin v.g. p.257). These fully automatic, probe-controlled, current-controlled MES systems today usually have a magnetic field probe triplet mounted fixed to the ship to record the earth's field at the ship's location and ship movements in the earth's field (course, lurching, pounding, yawing) (DE-PS 977 846). There is a separate compensation of the permanent, induced and eddy current components of the ship interference field in all three ship axes (vertical, horizontal and transept).

This known MES system has the following disadvantages:
For technical reasons, the probe system, the probe triple, cannot be attached to the vehicle for the cheapest measurement with optimal measuring conditions, but only where it is structurally possible.

The measurement signal of the probes in the earth's field is the sole control signal for the MES system. In the event of total failure of the probes, the system can therefore only be operated by hand, the so-called MES channels being controlled depending on the course. Probe errors are not easily noticed.

If the measurement signal is not generated by the earth's field, but by the ship's field, error detection is even more difficult and leads more to a misinterpretation and thus to an incorrect MES setting.

The further development of sensor technology has created a situation in which insufficient magnetic protection measures on the one hand pretend that the security is deceptive, but on the other hand give the intelligent sensor the opportunity to "hit" more precisely.

It is therefore necessary to adapt the effect of the MES system to the sensor development. This requirement applies both to vehicles in ferromagnetic construction and to vehicles in non-magnetic construction with partially ferromagnetic internals.

The invention is therefore based on the object of developing the device described at the outset in such a way that it provides substantially better and more reliable magnetic compensation for vehicles than the compensation with conventional MES controls. It is important to achieve an optimal magnetic protection state and to limit the measurement and control of the magnetic protection state from the outside to a minimum in order to increase the operational safety of the system at the same time.

The invention is intended to be able to be used on highly protected vehicles with an amagnetic and electrically non-conductive outer skin, on highly protected vehicles with a non-magnetic but electrically conductive outer skin and on vehicles with a ferromagnetic outer skin.

This object is achieved according to the invention in that process control with a digital data processor is provided,

to which a database is assigned in which
- Vehicle-specific data of the first measurement at the measuring location
- Location-dependent data on the geomagnetic conditions in the operating area of the vehicle (geomagnetic data)
are filed,

the on-board sensor for coil data, geomagnetic location, course and vehicle movements are assigned and

which controls the number of ampere turns of the compensation coils based on a predetermined sequence control (algorithms) in such a way that optimal compensation is ensured.

In the device according to the invention of a process-controlled MES system, the magnetic opposing fields to compensate for the magnetic effects occurring on or in the vehicle are controlled as a function of the geographical location, the course and the vehicle's own movement. The heart of the process-controlled MES system is an intelligent control system with a data processor that uses data storage (database).

The data storage contains the parameters that are required to achieve optimal control of the MES system. It is the data for the compensation

- the location-dependent magnetic effects
- The location and course-dependent magnetic effects
- The magnetic effects dependent on the vehicle's own movements in the earth's field
- The magnetic effects depending on operating conditions.

The magnetic fields of ferromagnetic objects such as internals and equipment in vehicles as well as their magnetic reaction in different operating states and when moving in the earth's field can be measured precisely. This also applies to the ferromagnetic or non-magnetic outer skin of the vehicle. With known data transmitters arranged inside the vehicle - without magnetic field probes - it is just as easy to determine the data about the course, location and own movement of the vehicle.

Furthermore, the data for the control of the MES system are stored in exceptional situations, so that the best possible setting is guaranteed even for a faulty system.

In the device designed according to the invention, the data previously obtained via magnetic field probes for the regulation or control of the ampere-turn numbers of the compensation coils are measured using the stored geometric data in conjunction with measured values relating to the geographical location and direct measurement of the vehicle's own movement and the operating states by corresponding sensors inside the vehicle.

The great advantage of the device according to the invention is that there is no need for a magnetic field probe system which is mechanically very easily damaged, as a result of which operational reliability can be increased considerably. The focus is no longer on the measurement and complicated compensation of probe signals, but on the actual regulation / control, with constant digital control. Operating states are taken into account without the detour via the probe reaction. The compensation must therefore be carried out optimally. The process-controlled MES system has particularly good uses or advantages on underwater vehicles, since it is always problematic to attach the gastro-field probes to the outer body of the submarines at an exposed point.

Worldwide use, less susceptibility to malfunction and better protection against magnetic sensors distinguish the vehicles which are equipped with the device according to the invention.

• FIG 1 bis 3 das Spulensystem einer MES-Anlage in einem Schiffskörper,
• FIG 4 bis 6 die magnetischen Schiffseigenfelder (Störfelder) in den drei Schiffskoordinaten,
• FIG 7 bis 9 die Größen der Induziertanteile beim Schlingern des Schiffes,
• FIG 10 ein Blockdiagramm der erfindungsgemäßen prozeß­gesteuerten MES-Anlage,
• FIG 11 bis 14 die schematische Darstellung des Informations­flusses bei der Kompensation mit vier unter­schiedlichen Kompensations-Algorithmen.

The invention is explained in more detail with reference to an embodiment shown in the drawings. Show it:

• 1 to 3 the coil system of an MES system in a hull,
• 4 to 6 show the magnetic fields of the ship (interference fields) in the three ship coordinates,
• 7 to 9 show the sizes of the induced portions when the ship lurches,
• 10 shows a block diagram of the process-controlled MES system according to the invention,
• 11 to 14 the schematic representation of the information flow in the compensation with four different compensation algorithms.

1-3 shows the large-scale, three-axis coil system of an MES system of a ship 1 (as an example of a vehicle as a ferromagnetic interference body). This coil system consists of coils 2, 3, 4 in the three orthogonal axes XYZ. Each coil 2 or 3 or 4 is usually divided into three sub-coils, which are no longer shown. One coil section (additional designation P) is used to compensate for a permanent vehicle-dependent interference field component. A second coil section (additional designation I) is used to compensate for an interference field component induced by the earth field.
Since vortex fields are induced in metallic parts of the system as a result of the ship 1's own movement in the earth's field, it is compensated for with a third coil section (additional designation E).

The magnetic ship fields - which are shown in FIGS. 4-6 - are usually designated as follows according to the ship coordinates:

Longitudinal ship component = X component (FIG 5)
Transept component = Y component (FIG 6)
Vertical component = Z component (FIG 4)

The XYZ coordinate system is assumed to be fixed to the object, ie it is oriented towards the generator of the magnetic interference field - in the exemplary embodiment ship 1.

4 shows the ship with the object-fixed coordinate system. In addition, the isolines 10 of the magnetic field are entered in a schematic form with purely vertical magnetization of the ship 1. A measurement of the vertical field component in the water depth MT would result in the basic course marked 11 below the ship.

FIG. 5 shows the ship 1 and the axes of the coordinate system in the same position as in FIG. 4, but now the isolines 12 of the magnetic field are shown in the case of pure longitudinal magnetization of the ship 1. A measurement of the vertical field component would have the basic course marked with 13 below the ship 1.

6 shows the ship 1 in a front view and correspondingly the y and z axes of the coordinate system. For this purpose, lines 14 of the same field strength are entered schematically with pure transverse magnetization of ship 1. If one measures the vertical component of the magnetic field with such a magnetization in the depth MT, the field course marked with 15 would result.

Under normal circumstances, a ship 1 has both vertical and longitudinal and transverse magnetizations, i.e. in all three coordinate directions.

The Z component of the ship's field created in this way is independent of the heading angle. The X component changes depending on the exchange rate according to a cosine function, which has its maximum value at the north and south rate and is zero at the east and west rate. The Y component also changes depending on the course, but according to a sine function which has its maximum value at the east and west course and is zero at the north and south course. All three components also change their value when the ship lurches and rams. The induced interference field components during lurching are shown in more detail in FIGS. 7-9. In the direction of its total, the earth's magnetic field generates the induced field vector S, which is divided into the components SZI and SYI according to the crossing angle of the ship 1.

The coils are in turn named according to their main magnetic directions of action. The coils 2 according to FIG. 1, which are parallel to the YZ plane, are the L coils (L-MES winding), whose magnetic axes of action lie in the longitudinal direction of the ship (L corresponds to the longitudinal direction).
The coils 3 according to FIG 2 (only one is shown), which are parallel to the XY plane, are the V-coils (V-MES winding) with vertical magnetic axes of action (V corresponds to vertical).
3, which are parallel to or in the XZ plane, are the A-coils (A-MES winding) whose magnetic direction of action lies in the Y-direction (A corresponds to athwort-ship).

Since, as mentioned, each coil 2 or 3 or 4 consists of three sub-coils with the additional ranges P, I, E, an MES system has windings (sub-coils) referred to below:

VI vertically acting induced field winding
VP vertical field permanent winding
VE vertically acting eddy current field winding
LI longitudinal field-acting induced field winding
LP fore and aft permanent field winding
LE longitudinal eddy current field winding
AI Inducted field winding acting across the ship
AP transversal permanent field winding
AE transversal eddy current field winding

The coil windings are fed with direct currents in different directions. The positive current directions result from the positive directions of the X-Y-Z coordinate system shown in FIG.

During the initial setting and during setting checks (magnetic measurement), the currents are set and the windings are switched so that the magnetic field of the hull, the so-called interference field, is optimally compensated for. During operation (travel), a controller or controller ensures that the set compensation is retained.

The basic principle of the device according to the invention is shown schematically in a block diagram in FIG. In this block diagram, 5 corresponds to the coil system consisting of coils 2-4 and 6 represents the vehicle equipped with sensors (ship 1). 7 denotes a measured value memory containing the current measured values and 8 denotes a database in which generally and long-term valid ones Data are stored. In a data processor 9, the measurement value memory 7 and the data 8 supplied to control values for the coil system 5 processed. The measured value memory 7 receives the current measured values from the measured value transmitters of the vehicle 6, whereby these measured value transmitters are not external magnetic field probes, but only transmitters for the detection of movements and the location of the vehicle.

In the process-controlled MES system according to the invention, the hardware core is an intelligent control system, the data processor 9 of which is fed into the coil system 5 of the vehicle by means of an integrated control and regulating method and a database 8 of fixed parameters and measured influencing variables (measured value memory 7) 6 controls based on a predetermined sequence control (control algorithms) so that optimal compensation is guaranteed. The control and regulation procedure is to be used on vehicles with an amagnetic outer skin, on vehicles with a non-magnetic but electrically conductive outer skin and on vehicles with a ferromagnetic outer skin.

All the data that the process-controlled MES system requires for the control to achieve optimal compensation are stored in the database 8 or are determined inside the vehicle 6 by sensors that are not magnetic field probes. The data in the database 8 are subdivided into data that are valid for all vehicles (generally valid data) and data that are typical of the vehicle and that apply for the long term. The geographic data are valid for all vehicles. The specific data of a vehicle are determined during the initial measurement. They show the dependency between the coil system 5 of the vehicle 6 in question and the influences of the earth field components.

The data processor 9 polls the influencing variables with a continuously running measuring program and thus supplies the control algorithms via the measured value memory 7 with the current data which are necessary for determining an optimal MES setting.

The data that the intelligent control system of the process-controlled MES system requires are divided into three groups. Groups 1 and 2 are general and long-term data and are therefore stored in database 8. Group 3 is current measurement data and is therefore supplied to the measured value memory 7.

• 1. Gruppe: Geomagnetische Daten (in Datenbank 8)
  • 1.1 Standortbereich 1 des Fahrzeuges
    • 1.1.1 Horizontales Erdfeld
    • 1.1.2 Vertikales Erdfeld
    • 1.1.3 Inklinationswinkel
  • 1.2 Standortbereich 2 des Fahrzeuges
• 2. Gruppe: Daten die bei der Erstvermessung ermittelt wurden (in Datenbank 8)
  • 2.1 Kompensation des Permanentfeldes
    • 2.1.1 Strom und Schaltung aller LP-Spulen
    • 2.1.2 Strom und Schaltung aller AP-Spulen
    • 2.1.3 Strom und Schaltung aller VP-Spulen
  • 2.2 Kompensation des vertikalen Induziertfeldes IV am Meßort
    • 2.2.1 Strom und Schaltung aller VI-Spulen
  • 2.3 Kompensation des horizontalen Induziertfeldes IH am Meßort auf Nordkurs (N)
    • 2.3.1 Strom und Schaltung aller LI-Spulen
    • 2.3.2 Strom und Schaltung aller AI-Spulen
  • 2.4 Kompensation des horizontalen Induziertfeldes IH am Meßort auf Ostkurs (O)
    • 2.4.1 Strom und Schaltung aller LI-Spulen
    • 2.4.2 Strom und Schaltung aller AI-Spulen
  • 2.5 Kompensation des Wirbelstromfeldes beim Schlingern am Meßort auf Ostkurs
    • 2.5.1 Strom und Schaltung aller AE-Spulen
    • 2.5.2 Strom und Schaltung aller VE-Spulen
  • 2.6 Kompensation des Wirbelstromfeldes beim Stampfen am Meßort auf Nordkurs
    • 2.6.1 Strom und Schaltung aller LE-Spulen
• 3. Gruppe: Daten die an Bord des Fahrzeuges gemessen werden (in Meßwertspeicher 7)
  • 3.1 Kontrolldaten aus der Spulenanlage
    • 3.1.1 Spulenströme
    • 3.1.2 Spulenwärme
    • 3.1.3 Spulenwiderstandswerte
  • 3.2 Bewegungsdaten
    • 3.2.1 Geographischer Standort
    • 3.2.2 Kurs
    • 3.2.3 Schlingerbewegung
    • 3.2.4 Stampfbewegung

Each group in turn contains systematically subdivided data sub-groups. The data groups can therefore be represented as follows:

• 1st group: Geomagnetic data (in database 8)
  • 1.1 Location area 1 of the vehicle
    • 1.1.1 Horizontal earth field
    • 1.1.2 Vertical earth field
    • 1.1.3 Inclination angle
  • 1.2 Location area 2 of the vehicle
• 2nd group: data determined during the first measurement (in database 8)
  • 2.1 Compensation of the permanent field
    • 2.1.1 Current and switching of all LP coils
    • 2.1.2 Current and switching of all AP coils
    • 2.1.3 Current and switching of all VP coils
  • 2.2 Compensation of the vertical induced field IV at the measurement location
    • 2.2.1 Current and switching of all VI coils
  • 2.3 Compensation of the horizontal induced field IH at the measurement location on the north course (N)
    • 2.3.1 Current and switching of all LI coils
    • 2.3.2 Current and switching of all AI coils
  • 2.4 Compensation of the horizontal induced field IH at the measurement location on the east course (O)
    • 2.4.1 Current and switching of all LI coils
    • 2.4.2 Current and switching of all AI coils
  • 2.5 Compensation of the eddy current field when lurching at the measuring location on the east course
    • 2.5.1 Current and switching of all AE coils
    • 2.5.2 Current and switching of all VE coils
  • 2.6 Compensation of the eddy current field when pounding at the measuring location on the north course
    • 2.6.1 Current and switching of all LE coils
• 3rd group: data measured on board the vehicle (in measured value memory 7)
  • 3.1 Control data from the coil system
    • 3.1.1 Coil currents
    • 3.1.2 Coil heat
    • 3.1.3 Coil resistance values
  • 3.2 Movement data
    • 3.2.1 Geographic location
    • 3.2.2 Course
    • 3.2.3 Rolling movement
    • 3.2.4 Pounding motion

A constant measuring program runs in the process control of the intelligent control system, which detects the control data from the coil system 5 and the movement data of the vehicle 6 and feeds them to the measured value memory 7. The movement data have a priority over the control data in triggering a reaction of the process control.

The sequence in the transaction data list is as follows:

- Course
- Swerve
- pounding
- geographical location

In the sequence control of the data processor 9, a reaction to a change in course is immediately reacted to, then to lurching and pounding and only then to another geographic location.

To determine the compensation of the individual magnetic effects, quasi-parallel processes run with different control algorithms, which are shown in FIGS. 11-14.

• 1) Bei der Kompensation der Permanentanteile sind gemäß FIG 11 nur die Daten der Gruppe 2.1 der Erstvermessung maßgebend. Die eingestellte Kompensation gilt weltweit.
  Bei der Kompensation des P-Anteils bleibt für die Regel­anlage des MES die Aufgabe, den eingestellten Spulenstrom und die elektrischen Werte des Spulensystems 5 zur P-Kompen­sation zu kontrollieren. Hierzu enthält der Datenprozessor 9 aus der Datenbank 8 und einem Überwachungssektor 7a des Meß­wertspeichers 7 die entsprechenden Werte. Über seinen Steuerausgang 9a kann der Datenprozessor 9 das Spulensystem bei Abweichungen entsprechend nachsteuern.
• 2) Die erdmagnetischen Einflüsse auf das Fahrzeug 6, das Indu­ziertfeld, muß in seine Komponenten zerlegt werden. Da die vertikale und horizontale Komponente IV und IH des Induziert­feldes unterschiedliche Auswirkungen auf den magnetischen Zustand des Fahrzeuges 6 haben, ist ihre Kompensation völlig getrennt vorzunehmen. Das durch die vertikale Komponente des Erdfeldes im Fahrzeug erzeugte vertikale Induziertfeld IV ist zwar standortabhängig, aber nicht kursabhängig. Das durch die horizontale Komponente des Erdfeldes im Fahrzeug erzeugte horizontale Induziertfeld IH dagegen ist standort- ­und kursabhängig.
  • a) Bei der Kompensation des verikalen Induziertfeldes IV gemäß FIG 12 greift der Regelalgorithmus daher nur ein, wenn eine Veränderung im geographischen Standort gemessen worden ist. Der Datenprozessor 9 erhält die zur Berech­nung eines Korrektursignals notwendigen Werte von der Datenbank 8 und einem die aktuellen Werte des Standortes bzw. der Standortänderung enthaltenden ersten Speicher­sektor 7b des Meßwertspeichers 7. Außerdem werden ihm von dem Überwachungssektor 7a die notwendigen Werte zugeführt. Durch das an seinem Ausgang 9b erscheinende Steuersignal werden die VI-Spulen entsprechend gesteuert.
  • b) Bei der Kompensation des horizontalen Induziertfeldes IH nach FIG 13 dagegen greift der Regelalgorithmus ein, wenn eine Kursänderung und/oder eine Veränderung im geographi­schen Standort gemessen worden ist. Der Datenprozessor 9 erhält hierzu neben den Werten aus der Datenbank 8 und dem Überwachungssektor 7a noch die aktuellen Werte aus dem ersten Speichersektor 7b und einem zweiten Speicher­sektor 7c, der die Meßwerte für den Kurs bzw. die Kurs­änderung enthält, zugeführt. An dem Ausgang 9c erscheinen die zur Steuerung notwendigen Steuersignale. Der Regel­algorithmus für die Horizontalkompensation soll auch das Gieren mit abfangen.
• Zur Ermittlung der gegenmagnetischen Maßnahmen gemäß vor­stehendem Regelalgorithmus benötigt daher die Prozeßsteue­rung der MES-Anlage den Standort und den Kurs des Fahrzeuges. Diese Information erhält die Prozeßsteuerung durch Kopp­lungen an die den Standort bestimmenden Geräte und den Kreiselkompaß oder im Notfall durch eine manuelle Eingabe. Der Inklinationswinkel und die Horizontalintensität des Erd­feldes und damit auch die Vertikalintensität ändern sich auf der Erde von Ort zu Ort. Im Rahmen der zugelassenen Abwei­chung von der Idealkompensation durch das Kompensations­system ist es möglich, die Navigationskarte in Standort­bereiche einzuteilen, wobei Isoklinen und Isodynamen bei der Flächeneinteilung zu berücksichtigen sind.
  
  Für diesen Standortbereich ist ein gültiger Horizontalwert und Verikalwert und der Inklinationswinkel festgelegt. Gleichzeitig sollten auch die geographischen magnetischen Anomalien berücksichtigt werden. Die Standortflächenkarte ist als Datei in der Datenbank 8 des MES-Prozessors abge­legt. Die Standortflächen brauchen nicht gleich groß zu sein, aber rechtwinklig unter Berücksichtigung der Längen- und Breitengrade der Navigationskarte eines bestimmten Maßstabes, um die rechnerische Standortflächenbestimmung zu beschleu­nigen.
  
  Jede Standortfläche mit ihren Eckdaten stellt ein "File" dar. In dieses File werden die Horizontalkomponenten und Vertikalkomponenten des Erdfeldes eingetragen; außerdem die Ströme zur Einspeisung in die Vertikalkompensationsspulen, da die Vertikalkompensation nicht kursabhängig ist.
  
  Für die Horizontalkompensation wird der Strom für eine Nord­kurskompensation und eine Ostkurskompensation eingetragen. Aus diesen Werten kann der Strom für die Horizontalkompen­sation auf jedem Kurswinkel rechnerisch bestimmt werden.
• 3) Die bisher angeführten Kompensationsmaßnahmen gegen das Induziertfeld gelten für ein Fahrzeug, welches sich auf einer Ebene bewegt.
  Bewegt sich das Fahzeug nicht auf ebenem Kiel, sondern macht das Fahrzeug Bewegungen, die bei einem Schiff mit Schlingern, Stampfen und Gieren bezeichnet werden, so muß die MES-Anlage auf diese Bewegung reagieren.

The individual partial windings and their current feeds are then treated according to the following criteria:

• 1) According to FIG. 11, only the data of group 2.1 of the first measurement are decisive for the compensation of the permanent components. The compensation set applies worldwide.
  When compensating for the P component, the task for the control system of the MES is to check the set coil current and the electrical values of the coil system 5 for P compensation. For this purpose, the data processor 9 contains the corresponding values from the database 8 and a monitoring sector 7a of the measured value memory 7. Via its control output 9a, the data processor 9 can readjust the coil system accordingly in the event of deviations.
• 2) The earth's magnetic influences on the vehicle 6, the induced field, must be broken down into its components. Since the vertical and horizontal components IV and IH of the induced field have different effects on the magnetic state of the vehicle 6, their compensation must be carried out completely separately. The vertical induced field IV generated by the vertical component of the earth field in the vehicle is location-dependent, but not course-dependent. The horizontal induced field IH generated by the horizontal component of the earth field in the vehicle, however, depends on the location and the course.
  • a) When compensating for the vertical induced field IV according to FIG. 12, the control algorithm therefore only intervenes if a change in the geographic location has been measured. The data processor 9 receives the values necessary for calculating a correction signal from the database 8 and a first memory sector 7b of the measured value memory 7 which contains the current values of the location or the change of location. In addition, the necessary values are fed to it by the monitoring sector 7a. The VI coils are controlled accordingly by the control signal appearing at its output 9b.
  • b) In contrast, when compensating the horizontal induced field IH according to FIG. 13, the control algorithm intervenes when a course change and / or a change in the geographic location has been measured. For this purpose, the data processor 9 receives, in addition to the values from the database 8 and the monitoring sector 7a, the current values from the first memory sector 7b and a second memory sector 7c, which contains the measured values for the course or the course change. The control signals necessary for control appear at the output 9c. The control algorithm for horizontal compensation is also intended to intercept yaw.
• To determine the counter-magnetic measures according to the above control algorithm, the process control of the MES system therefore requires the location and the course of the vehicle. The process control receives this information by means of couplings to the devices determining the location and the gyrocompass or, in an emergency, by manual input. The angle of inclination and the horizontal intensity of the earth's field and thus also the vertical intensity change from place to place on earth. As part of the permitted deviation from the ideal compensation by the compensation system, it is possible to divide the navigation map into location areas, whereby isoclinics and isody names must be taken into account when allocating the area.
  
  A valid horizontal value and vertical value and the inclination angle are specified for this location area. At the same time, geographic magnetic anomalies should also be considered. The location area map is stored as a file in database 8 of the MES processor. The location areas do not have to be the same size, but at right angles, taking into account the longitudes and latitudes of the navigation map of a certain scale, in order to accelerate the computational location determination.
  
  Each site area with its key data represents a "file". The horizontal components and vertical components of the earth's field are entered in this file; also the currents for feeding into the vertical compensation coils, since the vertical compensation is not price-dependent.
  
  For the horizontal compensation, the current is entered for a north course compensation and an east course compensation. From these values, the current for horizontal compensation can be determined mathematically at every heading angle.
• 3) The above-mentioned compensation measures against the induced field apply to a vehicle that is moving on one level.
  If the vehicle does not move on a flat keel, but the vehicle makes movements that are called rolling, pounding and yawing on a ship, the MES system must react to this movement.

There are two separate responses to movement to consider. To do this, it is necessary to record the vehicle movements. The movements of lurching or pounding can be recorded either by roller ball encoders or gyro encoders. The yaw is detected by a gyro and treated like a course change.

Due to the constantly changing position of the vehicle in the earth's field, the induced field is also constantly changing. This also makes it necessary to change the counter-magnetic measures. The reactions of the vehicle are through electrically simulated movements during the first measurement under the magnetic conditions of the measuring location have been determined. With the help of the determined reaction parameters and the earth field components of the location, the movement-correct magnetic reaction of the induced field MES becomes a linear control problem.

The second reaction to movements such as lurching, pounding and yawing is the generation of swirl fields in vehicles with large internals made of conductive material or vehicles which are made entirely or partially of conductive material. Movement in the earth's field creates induction currents in the conductive materials, so-called eddy currents, which in turn generate magnetic fields. The swirl fields occur almost 90 ° out of phase and are dependent on the roll and pound frequency.

Of the magnetic field components, the subcomponents P = permanent component, IV = the vertical induced field component generated by the vertical earth field component, IHN = the horizontal induced field component generated by the horizontal earth field component on the north course and IHO = the horizontal induced field component generated by the horizontal earth field component on the east course 8th.

In addition to the sub-components P, IV, IHN and IHO, the following information is also required to calculate an interference field of a ferromagnetic object on any course and at any point on earth:

- the course angle FI
- the vertical proportion of the earth's field at the EVM site
- The vertical earth field share at the "computer location" EVR
- The horizontal portion of the earth's field at the EHM site
- The horizontal earth field share at the "computer location" EHR

Here, "measurement location" means the location of the measurement of the vehicle and "computer location" the current location of the vehicle.

The earth field components are to be specified in a uniform unit of measurement. Which unit is used when specifying the earth field components is irrelevant. A vertical factor VF and a horizontal factor HF are determined from the information and this becomes dimensionless. The following applies:

VF = EVR / EVM and
HF = EHR / EHM

The vortex fields require their own compensation program, the reaction parameters of which in turn were determined during the initial measurement with electrically simulated movement. To simplify the swirl field compensation should be operated with a second processor in master-slave mode.

In the compensation of the eddy current fields according to FIG. 14, the control algorithm intervenes when the motion sensor indicates a movement of the vehicle about its longitudinal and transverse axes. In addition to the required values from the database 8, the current values from the first and second memory sectors 7b and 7c, the data processor 9 also receives the current values of the pounding and rolling movements which are contained in a third and fourth memory sectors 7d and 7e. Via its output 9d, the data processor 9 supplies the necessary control signals for the compensation of the control field caused by the corresponding vehicle movements.

The effectiveness of the control algorithm by which the roll movements according to FIGS. 7-9 are included in the process-controlled MES system depends on the quality of the setting data (data subgroups 2.5 and 2.6) determined during the initial measurement.

The following example should show how the control algorithms are derived from a method for calculating the interference field of a ferromagnetic object at any desired course at any point on earth:

In the magnetic measurement of ferromagnetic objects, the components of the self-magnetic field are measured in coordinate directions X, Y and Z and stored. The coordinate system is object-fixed for easier handling. In this fixed coordinate system, the component points in the X direction to the bow of the object and thus to the top edge of the matrix, the component in the Y direction to the right of object and matrix, and the component in the Z direction downwards. When storing data in the computer in the form of matrices for the other main courses, regardless of the type of measured value recording, care must be taken to ensure that the bow of the object, and thus the component in the X direction to the upper edge, is ensured by folding or falling or by reversing the sign of the measured value matrix of the matrix, the component in the Y direction to the right and the component in the Z direction down.

The first step in solving the worldwide interference field calculation of an object is the calculation of the interference field on every course at the measuring location.

The permanent component P, the vertical induced field IV and the horizontal induced field components on the north or east course IHN and IHO are parameters of the calculation. In the calculation, the horizontal induced field portion IHN on the north course behaves like the cos the course angle FI, the horizontal induced field portion IHO on the east course behaves like the sin of the course angle FI.

The interference field HSF for the components in the coordinate directions X, Y and Z is in each case with the formula prepared for programming

HSF = P + IHN × COS FI + IHO × SIN FI + IV

expected.

When calculating an interference field of an object at the measurement location on different courses, the permanent component P and the vertical induced field component IV caused by the vertical earth field component always remain the same. If the interference field of an object is to be calculated for a location with other geomagnetic conditions than at the measurement location, the horizontal factor HF and the vertical factor VF must be inserted in the calculation specification.

Prepared in a form that is favorable for programming, the following calculation rule results for the interference field HST of an object with different geomagnetic conditions than at the measuring location:

HST = P + (IHN × COS FI) × HF + (IHO × SIN FI) × HF + IV × VF

As already indicated, the subcomponents are taken from the database 8.

The earth field values of the horizontal and vertical earth field for the measuring location can be firmly agreed in the computer program. The earth field components of the locations for which the interference field of the object is to be calculated can also be present in the database 8 if used frequently. An entry for nonexistent data should be provided.

Claims (10)

1.Device for controlling a magnetic self-protection (MES) system of a vehicle, which has a large, three-axis coil system consisting of current-carrying coils in the three orthogonal vehicle axes to compensate for the earth's magnetic field at the vehicle location and the vehicle's movement in the earth's magnetic field (course, roll, etc. ) has a dependent magnetic field of the vehicle,
characterized by
that a process control with a digital data processor (9) is provided, to which a database (8) is assigned, in which
- Vehicle-specific data of the first measurement at the measuring location
location-dependent data on the geomagnetic conditions in the operating area of the vehicle (geomagnetic data) are stored,
the on-board vehicle (ship 1) transducer for coil data, geographic location, course and vehicle movements are assigned, and
which controls the ampere turns of the compensation coils based on a given sequence control (algorithms) in such a way that optimal compensation is guaranteed. 2. Device according to claim 1,
characterized by
that the data of the first measurement data for the compensation of the permanent field (P), the vertical induced field (IV) and the horizontal induced field (IHN and IHO) on the north and east course as well as for the compensation of the eddy current field when rolling on the east and when pounding on the north course, each related to the measurement location. 3. Device according to claim 1 or 2,
characterized by
that the data obtained on board the vehicle are control data from the coil system (coil current, heat, resistance values) and movement data (geographical location, course, roll and ramming movements). 4. The device according to claim 3,
characterized by
that the sequence control has a priority circuit, such that when a process control response is triggered, the movement data have priority over the control data and the following order of priority exists within the movement data list:
- Course
- Swerve
- pounding
- geographical location. 5. The device according to claim 1 or one of the following,
characterized by
that in the process control different sequence controls (algorithms) for determining the manipulated variables for setting the ampere turns of the coils for compensation
- the magnetic permanent field (P),
- the horizontal magnetic induced field (IH),
- The vertical magnetic induced field (IV) and
- the magnetic eddy current field
are provided. 6. The device according to claim 5,
characterized by
that the sequence control are designed so that
in the compensation of the permanent field (P), a first algorithm forms the manipulated variable on the basis of the data from the first measurement,
a third control algorithm is provided for the compensation of the vertical induced field component (IV), which causes the compensation when a course change and / or a change in the geographical location is measured,
- A fourth control algorithm is provided for the compensation of the eddy current fields, which forms the manipulated variable for the compensation on the basis of signals associated with motion sensors for movements of the vehicle about its axes. 7. The device according to claim 6,
characterized by
that a second data processor is provided for swirl field compensation, which is connected to the first data processor (9) in master-slave mode. 8. The device according to claim 6 or 7,
characterized by
that the control algorithm for the compensation of the horizontal induced field (IH) is designed so that it also includes the compensation of the vehicle movement "yaw". 9. Device according to one of claims 1 to 7,
characterized by
that the geomagnetic data are related to given rectangular areas of the earth's surface taking geographic magnetic anomalies into account. 10. The device according to one of claims 1 to 9,
characterized by
that rolling ball or gyro sensors are provided to detect the vehicle's own movements (roll, pound, yaw).

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