DE2953100C1 - High voltage transformation and rectifier device - Google Patents

Description

- That the primary windings (1) are designed in the form of rectangular flat coils (11), their vertical parts in pairs along the axis of the common window of each vertical column (7) the cores (9) are arranged,

- That the potential shields (5, 6) in the form of an axially symmetrical system of ring-shaped Sections (20, 6 ') surround the vertical columns (7) of the cores (9) on the outside and inside,

- That each one of the sections (20) of the external potential shield (5) is electrically connected to the star point of the sections (10) of the secondary winding (2),

- That the positive pole (27) of one of the bridge rectifiers (24) is grounded and

- That the vertical columns (7) of the cores (9) and the blocks (3) of the bridge rectifiers (24) in an insulating frame (8) are attached.

2. High-voltage device according to claim 1, characterized by the vertical sections of the In pairs arranged therein coils (U) of the primary winding (1) comprehensive, electrically conductive grounded Umbrellas (12) which are designed as cylinders with cutouts along their generatrix.

3. High-voltage device according to claim 1 or 2, characterized in that the insulating frame (8) for the cores (9) is designed in the shape of a prism with three concave surfaces, which are separated by segment sections (14) dielectric cylinder are formed and have transverse cutouts (15) in which the ring-shaped cores (9) attached to the coils (10) of the secondary winding (2) by means of insulating rods (16) are.

4. High-voltage device according to one of claims 1 to 3, characterized in that the High-voltage output is formed by a cable (19) without braiding and that the sections (6 ') the potential shield (6) for the blocks (3) of the bridge rectifier (24) on the surface of the cable (19) and attached concentrically to it.

The invention relates to a high-voltage transformation and rectifier device of the im

ίο prerequisite for the preamble of claim 1 Kind, as it is known from FR-PS 15 65 646.

A high-voltage transformer and rectifier device assumed to be known is as a coaxial system carried out by an acceleration tube, a subdivided secondary winding, a also subdivided magnetic conductor and a primary winding is formed and one of the elements mentioned has comprehensive common housing. The working magnetic flux generated by the primary winding is partially closed via non-magnetic elements of the device and induced in each section of the secondary winding an alternating voltage, which is converted into a direct voltage with the help of the built-in accelerator tube is converted.

In this transformation and rectification device, however, the magnetizing current has a direct current component on, and the magnetic flux is across the non-ferromagnetic space of the accelerating tube closed.

This leads to an increase in the installed power of the feed system as well as to a lower reliability and working reserve for the accelerator, as the feed system and the electron acceleration path are not decoupled either structurally or in terms of circuitry.

A high-voltage transformation and rectifier device is also known (SU-Urheberschein 5 00 719) intended to feed a direct-acting electron accelerator and similar like that according to the FR-PS 15 65 646 is constructed.

In this known device, however, there are difficult operating conditions for the insulation Sub-optimal structure of the electric field in the work area, with high reactance and a low one Power factor with an output voltage of several hundred kV and taking into account the Voltage between the star point of the secondary winding and the earthed magnetic conductor and twice that the full rectified voltage and thus a low operational reliability of the device in the event of overvoltages in the system and during normal operation of the facility. In addition, the Isolation to a more complicated structure of the electric field in the working space of the facility, and at a breakthrough in a part of the secondary winding results in a state of damage for the entire facility, because the magnetic flux is displaced here from the rod-shaped spatial magnetic conductor that is responsible for all parts is common to the secondary winding.

In this arrangement, the reactance also increases, with the voltage losses also inevitably occurring in the Time intervals of commutation of valves become larger. In practice, the leakage inductance is Transformer 15 to 20%. This results in poorer energetic parameters of the facility, since the outer characteristic curve begins to decrease and the converter consumes considerable power for the valves, what by increasing the commutation

winkcls of the valves is conditional, and a lower reliability with uninterrupted operation of the facility as a whole, since there is no decoupling of the damage states is given in the source of nourishment and in the burden.

On the other hand, from CH-PS 4 71 447 it is known per se for a transformer, the primary windings in the form of rectangular flat coils, the vertical parts of which are each along the axis of the window each vertical column of the magnetic cores are arranged.

Finally, from US-PS 33 98 348 an electrical high-voltage converter device and a pulse transformer known for the potential shields in the form of an axially symmetrical system The vertical columns of the magnetic cores are surrounded by ring-shaped sections on the outside and inside.

The invention is based on the object of a high-voltage transformer and rectifier device to develop a new design that improves the reliability of the Main insulation and a higher specific volume output, better energetic parameters such as reactance and power factor results in a reduction in weight and size and the creation of a compact and reliable high-voltage supply source with a rigid external characteristic.

This object is achieved according to the invention by the features of claim 1.

Advantageous further developments of the invention emerge from the subclaims.

In the drawing, the invention is preferred based on Embodiments illustrated; it shows

Fig. 1 shows a structural design of a high-voltage transformation and rectifier device in a front view partially cut along the axis of symmetry of the magnetic conductor;

2 shows a section through the high-voltage device from Fi g. 1 along line 11-11 in FIG. 1;

F i g. 3 shows a structural part of a high-voltage device in a partially along the axis of symmetry axonometric representation of the magnetic conductor in section; and

F i g. 4 an electrical circuit diagram for the valve blocks of a high-voltage device and the connections the valve blocks to other elements of the facility.

The in F i g. 1 shown high voltage device includes a three-phase step-up transformer with a Spatially distributed magnetic conductor, which consists of a primary winding 1 of the multiple turns Transformer and a subdivided secondary winding 2 carries. At this valve blocks 3 are connected, the form a bridge circuit and are arranged parallel to the axis of symmetry 4 of the magnetic conductor.

The device is with a potential screen 5 for the star point conductor of the secondary winding 2 and with equipped with a potential shield 6 for the blocks 3, which consist of ring-shaped insulated sections 20 and 6 ' exist.

The spatially distributed magnetic conductor is designed in the form of three vertical columns 7 (FIG. 2), each of which de column of mutually insulated and fixed in an insulating frame 8 ring-shaped cores 9 (Fig. 1) exists, which have a common window and toroidal coils (sections) 10 of the secondary winding 2 carry.

The primary winding 1 consists of three rectangular flat coils II (FIG. 3), the vertical legs of which are in pairs along the axis of the common window of each vertical column 7 of the cores 9 are arranged.

The vertical legs of each pair of flat coils 11 the primary winding 1 are in their own electrically conductive and grounded electrostatic screen 12 built in, which is designed as a cylinder with cutouts along its generatrix and the vertical legs the flat coils 11 belonging to the primary winding 1.

Each electrostatic screen 12 is insulated by means of a film 13.

The insulating frame 8 (Fig. 2) is prism-shaped with three Executed concave surfaces, which are formed by segment sections 14 of dielectric cylinders and transverse cutouts 15 (F i g. 1) for receiving the cores 9 with the toroidal coils 10 of the secondary winding 2, which are fastened in the transverse cutouts 15 by insulating rods 16 (FIG. 2). The insulating rods 16 are also like the main insulating rods 17 of the device used in profiled insulating plates 18.

A located in the symmetry axis 4 (Fig. 1) of the magnetic conductor is used as the high-voltage output of the device Cable 19 without braiding, the sections 6 'of the potential shield 6 for the blocks 3 on top of one another on the surface of the cable 19 and concentrically therewith along the height of the vertical columns 7 (Fig. 3) are arranged.

The potential shield 5 intended for the star point conductor of the secondary winding 2 consists of ring-shaped ones insulated sections 20 (profiled electrically conductive rings), which along the height of the columns 7 one above the other are arranged and all three pillars 7 comprise.

A hermetically sealed conductive housing 21 (Fig. 1) for containing the entire device has a metal cover 22 with bushings 23 and is covered with a gaseous or liquid insulating material filled, which serves as a cooling medium.

The bridge circuit formed by blocks 3 (Figure 4) consists of individual bridge rectifiers 24 with six branches 25 each.

The connection point 26 of the corresponding branches 25 of a bridge rectifier 24 is at the beginning the corresponding toroidal coil 10 of the secondary winding 2 is connected.

The ends of the three star-connected toroidal coils 10 of the secondary winding 2 are connected to the corresponding Section 20 of the potential shield 5 intended for the star point conductor of the secondary winding 2.

The center connections of the toroidal coils 10 are galvanically connected to the corresponding cores 9.

The positive pole 27 of the first (upper) bridge rectifier 24 is grounded, while the negative pole 28 of the The last (lower) bridge rectifier 24 is electrically connected to the cable 19 via a plug connection 29 is.

The intermediate poles 30 of the bridge circuit are in galvanic connection with the corresponding sections 6 'of the potential shield 6 for the blocks 3, which in turn are electrically connected to the cable 19.

The high-voltage device shown works in the following way:

When the primary winding 1 of the transformer is connected to the network, it flows through the flat coils 11 Current that magnetizes the spatially symmetrical magnetic system. The magnetic flux is here in the individual cores 9 localized and induced a three-phase system of electromotive forces in the Secondary winding 2 toroidal coils 10.

The sections 20 of the potential shield 5, all three

Vertical columns 7 with the cores 9, ensure the compensation of stress gradients that arise between the individual toroidal coils 10 of the secondary winding 2 and between the magnetic conductor and the conductive housing 21 (Fig. 1) result.

In this case, there is a gradual increase in potential on the subdivided potential shield 5 from top to bottom reached below along the vertical columns 7 consisting of the cores 9 (FIG. 3).

The one removed from the connection points 26 (FIG. 4) of the toroidal coils 10 of the secondary winding 2 system three-phase AC voltage is rectified in the cascade bridge circuit, which is carried out by the blocks 3 interconnected to form three-phase bridge rectifiers 24 is formed. The high DC voltage rises along the axis of symmetry 4 (Fig. 1) of the magnetic conductor in stages from the upper bridge rectifier 24 (Fig. 4) with a grounded positive pole 27 to the lower bridge rectifier 24, the negative pole 28 is connected to the cable 19. Here is the line voltage between the elements of the three vertical columns 7 (Fig. 3) of the spatial magnetic conductor structure is not higher than the rectified voltage of a stage which / Is 7 times smaller than the output voltage. Thanks to the localization of the magnetic fluxes in individual cores 9 an inevitable division of the rectified voltage by individual bridge rectifiers occurs in the circuit 24 (Fig. 4). The power output from the facility occurs over the entire length of the Cable 19, which is connected to the lower high-voltage negative pole 28, the system with the Sections 6 'galvanically connected intermediate poles 30 a uniform division of the potential over the insulation surface of the cable 19 guaranteed.

In the nominal operating state, the device has minimal magnetic stray fields, a rigid external characteristic and a low dependence of the DC output voltage on the load current value. The enlarged The surface of the spatially distributed magnetic conductor ensures good heat dissipation from the toroidal coils 10 of the secondary winding 2 and from the cores 9.

In the event of rollover in the load, e.g. B. in an electron gun, provides the grounded screen 12 of the flat coils 11 for a good capacitive decoupling from the circuit of the rapid transitions on the side the secondary winding 2 and thus offers good protection for the primary control part of the device.

If a reversible breakdown occurs in the toroidal coil 10, the high-voltage device delivers furthermore a constant output voltage. Here, the magnetic flux from the cores 9 is only in one Step displaced, the magnetic induction in all other cores 9 increases proportionally. In order to an accidental brief short-circuit of the toroidal coil 10 of the secondary winding 2 does not constitute a damage state for the whole facility.

In various applications, the proposed design of the high-voltage device has the following advantages. The structure of the magnetic conductor sections with ring-shaped cores (toroidal cores) 9 ensures a minimal length of the magnetic lines of force and a minimal strength (less than 5%) of the idle reactive current. Within the limits of each section of the Miignetleilers the magnetic flux is always closed in the direction of rolling of the sheet metal or strip material. The enlarged surface of the insulated cores 9 creates good cooling conditions when operating in a gaseous or liquid insulating medium. Each core 9 is at the potential of the center connection of the corresponding toroidal coil 10, which is why the insulation of the secondary winding 2 from the core 9 is only calculated for half the voltage of a stage, which is η times smaller than the output voltage. An insulating frame 8 (FIG. 2) is used to fasten the cores 9 and consists of segment sections 14 of dielectric cylinders (e.g. made of glass fiber-epoxy composite) with transverse cutouts 15 (FIG. 1). This insulating frame 8 (FIG. 2) is designed as a regular prism with concave surfaces and is used to decouple the mechanical and the insulation structure of the spatially distributed magnetic conductor. Such a Geis substitute 8 takes over the mechanical load and at the same time ensures a maximum cooling surface of the cores 9, which is in contact with the cooling medium (gaseous insulating material or transformer oil).
The main insulation of the spatially distributed magnetic conductor consists of the insulation of the coaxial system, which is formed by the earthed screen 12 (Fig. 3) comprising the vertical legs of the primary frame-shaped flat coils U in pairs and the system of cores 9 with the toroidal coils 10 of the secondary winding 2 . Such an isolation can easily be calculated and z. B. be designed as a paper and film cylinder immersed in a liquid insulating material or as a pure oil channel.
The system of sections 20 of the ring-shaped electrically conductive potential shield 5 concentrically comprises all the vertical columns 7 consisting of the cores 9 and is used to generate a uniform structure for the electric field in the radial direction and for the gradual normalization of the electric field gradient in the axial direction of the high-voltage device. The section with the highest potential is in the lower part of the facility.

Since the toroidal coils 10 of the secondary winding 2 feed the bridge rectifiers 24 (FIG. 4), their branches 25 form the symmetrical spatial structure, this firstly results in an inevitable potential division along the circuit of blocks 3 and secondly, an optimal utilization of the working volume is achieved.

The power decoupling from the device takes place with the help of a high voltage output, the longitudinal the axis of symmetry 4 (Fig. 1) of the spatially distributed magnetic conductor is arranged and a high-voltage cable 19 (Fig. 3) without braiding. This cable 19 is made of electrically conductive rings (sections) 6 'enclosed, which are at the same intervals that the insulating space between the cores 9 correspond.

The homogeneous axial structure of the electric field is retained here.

In contrast to the known solution, in which the axial structure of the electric field comprises the isolation of the star point from the earthed shielded magnetic conductor, the isolation of the magnetic conductor from the high-voltage pole (shield) and the isolation of the pole from the housing, the device shown is in the axial direction only calculated for the inter-pole voltage of blocks 3 (FIG. 4), with a higher reliability of the entire system being achieved.
The geometric arrangement of the primary winding 1 ensures that the magnetic flux is localized within the limits of the ferromagnetic material of the cores 9, the stray field and the stray inductances remaining very small (practically below 3%).

The device has a rigid external characteristic curve with a minimal voltage drop in the time intervals the valve commutation, whereby the consumption of the valve reactive power is also small.

Thanks to the subdivision of the secondary winding 2, the blocks 3 and the potential shields 5, 6, isolation from the full line voltage is not required in the device shown. In practice, the radial insulating distance between the vertical columns 7 (FIG. 3) consisting of the cores 9 with the toroidal coils 10 is determined by the conductor voltage of a stage which is n times smaller than the full conductor voltage of the device.

The invention can be used to power various electrophysical Devices, in particular for feeding technological electron beam systems for electron beam welding, Soldering and cutting of metals, as well as for pumping high power electroionization lasers.

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For this purpose 4 sheets of drawings

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Claims (1)

Patent claims: 1. High voltage transformation and rectifier device with bridge rectifiers and one Three-phase step-up transformer, which transformer has a spatially distributed magnetic conductor contains, which is interspersed with primary windings and a number of superimposed Cores consists, the magnetic conductor is designed in space in the form of three vertical columns, which in of the plane forming the apexes of an equilateral triangle, the secondary windings being made up of sections consist, arranged on each core and connected to the blocks of bridge rectifiers, which are successively connected, one of the poles of the bridge rectifiers being grounded, and the cores with the sections of the secondary windings and the bridge rectifiers with potential shields are equipped, the bridge rectifiers with the sections arranged at the same height the secondary windings are electrically connected to a high-voltage output, which is arranged along the symmetry axis of the transformer, and wherein the blocks of Bridge rectifiers symmetrically along the circumference between the vertical columns of the cores are arranged, characterized in that