Power supply device for immediate electric heating of pipeline system

FIELD: electrical engineering.

SUBSTANCE: power supply device (100) for immediate electric heating of a pipeline system contains basically a three-phase transformer (2), a symmetrisation unit (14), a compensation unit (22). The three-phase transformer (2) is adapted for supporting a single-phase load connected between the first phase (6) and the second phase (8) of the transformer (2). The transformer (2) contains at least one first tap switch (10) on the high-voltage side (12) of the transformer (2). The symmetrisation unit (14) contains the first capacitor means (16) connected between the first phase (6) and the third phase (18) of the transformer and an inductor means (20) connected between the second phase (8) and the third phase (18) of the said transformer (2). The compensation unit (22) contains the second capacitor means (24) connected between the first phase (6) and the second phase (8) of the transformer (2). The first tap switch (10), the first capacitor means (16), the second capacitor means (24) and/or the inductor means (20) are adapted for variation under load.

EFFECT: changing the value of capacity and inductivity of the corresponding capacitive and inductive means under load and optimisation under load on a real time basis.

7 cl, 4 dwg

 

The present invention relates to electric heating systems piping. More specifically, the invention relates to a power supply system for supplying electric power to the pipeline.

The formation of hydrates is a well-known problem in systems for subsea production of oil and gas. There are several solutions to this problem. Traditionally used chemicals. Recently used a more efficient way of direct electrical heating (DEH) for heating the pipe by passing a high electric current through the actual pipeline. Any form of electric heating pipe usually requires a source of electrical power, issuing at least several hundred kilowatts. Often you want to make power in a programmed sequence to achieve the selected operating conditions. The power is converted from three-phase to single-phase, it is often necessary, especially in applications of underwater pipelines, where power is taken from the existing three-phase electrical network. Looking for an efficient universal power supply system that can meet these needs.

The purpose of this invention is the provision of an improved device power supply for direct electric is one heat.

The above objective is achieved by the device power supply for direct electric heating of a pipeline system, containing

three-phase transformer, adapted to support a single-phase load connected between the first and second phases of the transformer, and the said transformer includes at least one switch branches on the high-voltage side of the transformer;

unit balancing, containing the first capacitor means connected between the first phase and the third phase of the transformer, and inductor means connected between the second phase and the third phase of the above mentioned transformer; and

the compensation unit containing a second capacitor means connected between the first phase and the second phase of the transformer,

the first switch branch, the first capacitor means, second capacitor means and inductor means adapted to vary under load.

Single-phase cables are used for heating of the pipeline. The cables are connected to three-phase power source. Single-phase load is converted to three-phase load for three-phase transformer with unit balancing, containing the first capacitor means and inductor means. In addition, the block of the compensation, containing the second capacitor means is used to compensate for low power factor loads. If the load is not compensated and is not symmetrization, balanced load would be very high and would lead to high current reverse order. This would have created problems for reliable operation of the transformer and generators. The heating load for DEH can be selected in the range from minimum to maximum load by changing the voltage applied to three-phase transformer. By changing the voltage level of the power level of heating can vary. This is done using the switch branch under load connected on the side of the high voltage transformer while the transformer and all the DEH system is under stress. This solution allows you to change the values of capacitance and inductance of the respective capacitive and inductive means under load, while the system is powered on. This allows for optimization under load in real time, where the power factor of the transformer will be very close to unity, and the current reverse sequence will be very close to zero.

In a preferred embodiment of the invention the modules within the above-mentioned structure d is further include a control unit, adapted to automatically control the voltage levels mentioned first switch branch, capacity mentioned first capacitor means and said second capacitor means and inductor mentioned inductor means. This allows you to automatically control transformer, capacitor means and inductor means, when the piping system is fully energized. It also provides for automatic control system that can be temporarily disconnected from the supply. The control unit may be a programmable logic controller (PLC), managed on site or from a remote location.

In an alternative embodiment, a three-phase transformer further comprises at least one second switch branch. The second switch branch can act as a switch branch operational (not under load), and through the use of branches operational profile will be extended beyond the commonly proposed range, allowing you to switch to other positions tension.

In another alternative embodiment, the inductance of the inductor means is adapted to change under load with use the of the third switch branches. The inductance of the inductor means you need to change in order to balance the load, that is, to transform single-phase load in a three-phase load. Switch branch contributes to the change in inductance when the piping system is fully powered.

In another alternative embodiment, the automatic capacity management mentioned first capacitor means further comprises the step of switching at least one first additional capacitor using the appropriate vacuum contactor. Automatic capacity management mentioned second capacitor means further comprises the step of switching at least one of the second additional capacitor using the appropriate vacuum contactor. It provides change under load capacity in accordance with the measured parameters of the load and the capacity requirement for the DEH system.

In another alternative embodiment, the transformer, the first capacitor means, second capacitor means, inductor means, first capacitor, second capacitor and the vacuum contactor are the corresponding components of the dry type. The use of the above components is s lowers the potential risks against fire, thereby providing greater security.

The present invention is additionally described below with reference to illustrated embodiments of shown in the drawings, which represent the following:

figure 1 - diagram of the power supply for the pipeline system,

figure 2 - device power supply control unit according to a variant implementation of the present invention,

figure 3 - transformer with switch branch established on the side of the high voltage (HV), and branches not under load-side low voltage (LV) according to a variant implementation of the present invention,

figure 4 - the structure of the system balance the load according to a variant implementation of the present invention.

The invention aims at providing a solution that enables fully automated operation.

This solution provides fully-automatic tuning capacitor and inductor means under load. The voltage transformer is changed using a combination of the switch branch under load and branches not under load. This provides the possibility of continuous operation under load and requires a rare stop DEH system.

Figure 1 shows the diagram of a device 100 source : who and power supply to the piping system. Power can be removed from an existing three-phase network 1 power supply. The device power supply contains a three-phase transformer 2, adapted to support a single-phase load 4 connected between the first phase 6 and the second phase 8 of the transformer 2. The transformer contains side 12 of the high-voltage side 3 low voltage, the first switch 10 branches connected with the side 12 of the high voltage transformer 2. The device includes a block 14 of balancing that contains the first capacitor means 16 connected between the first phase 6 and the third phase 18 of the transformer, and inductor means 20, connected between the second phase 8 and the third phase mentioned 18 of the transformer 2. Single-phase load is transformed into a three-phase load for three-phase transformer using this block. Block 22 compensation is also entered in the device and includes a second capacitor means 24 connected between the first phase 6 and the second phase 8 of the transformer 2. This unit compensates for low power factor loads. Based on this requirement, capacitive and inductive values associated with the blocks of balancing and compensation can vary. The first switch 10 branches, the first capacitor means 16, the second capacitor with adsto 4 and inductor means 20 adapted to vary under load. Switches branches under load enable input voltage, while the DEH system remains under voltage (under load). This allows for optimization under load in real time, where the power factor of the transformer is very close to unity, and the three-phase load on the transformer is very well balanced, i.e. leads to a very low current reverse order.

Figure 2 illustrates the device 200 power supply unit 202 according to a variant implementation of the present invention. The device power supply is shown as containing a control unit 202, which is adapted for automatic control of the said switch 10 branches, the first capacitor means 16, second capacitor means 24 and inductor means 20. Here, the control unit 202 is a programmable logic controller (PLC), managed on site or from a remote location and perform automatic control. The device power supply also contains at least one first block 204 measurement to measure single-phase load and at least one second block 206 measurement for measurement of three-phase loads. The measured parameter is the load may be a power factor of the cable, voltage, current, etc. of the Device power supply could further be controlled from a remote location using panel 208 remote control.

Figure 3 shows a device 300 transformer with switch 302 branches, mounted on the side 12 of the high voltage (HV), and many branches not under load side 3 low voltage (LV) according to a variant implementation of the present invention. Switches branches under load and branch not under load allow you to change the voltage and power for direct electrical heating (DEH), while the transformer and all DEH system remains energized. Transformer, shown here, contains the switch 302 branches under load with nine voltage levels or positions. The drawing also shows two fixed positions of the branches provided at 77% and 60% of normal voltage, in addition to the normal fixed position branch at 100% of normal voltage on the low voltage side. Normal locked position 304 branches shown at 100% of normal voltage to the first fixed position 306 branches at 70% of normal voltage and a second fixed position 308 branches at 60% of normal voltage, Respectively, this device allows you to get 3*9=27 different provisions or voltage levels in the full required range power. For transformers larger size can be selected branches under load with a large number of positions, for example, up to 36 branches under load, to switch without interrupting the load. Similarly you can change the number of branches selected items.

Figure 4 shows the schematic device 400 counterbalance system load according to a variant implementation of the present invention. As shown, the capacitive value of the first capacitor means 410 and the second capacitor means 420 are controlled by switching additional smaller capacitor blocks. Additional capacitors are connected to the circuit using vacuum contactors. The first additional capacitors 412, 414, 416 are connected to the circuit according to the requirement of next to the first capacitor means 410, using the appropriate vacuum contactor, 413, 415, 417. The same is true for the second capacitor means 420. The second additional capacitors 422, 424, 426, 428, 430 are connected to the circuit according to claim next to the second capacitor means 420, using the appropriate vacuum contactor, 423, 425, 427, 429, 431. As pok is connected, the inductance of the inductor means 406 is controlled by the switching branches using switch 408 branches under load. Transformer, a first capacitor means, second capacitor means, inductor means, first capacitor, second capacitor and the vacuum contactor are components of the dry type. The use of the above components reduces the potential risks of fire, thereby providing greater security.

In summary, the present invention relates to a device power supply for supplying electric power to the pipeline. The device 100 power supply for direct electric heating of a pipeline system contains mainly three-phase transformer 2, block 14 balancing and compensation block 22. Three-phase transformer 2 is adapted to support a single-phase load 4 connected between the first phase 6 and the second phase 8 of the transformer 2. The transformer 2 comprises at least one first switch 10 branches on the side 12 of the high voltage transformer 2. Block 14 contains the first balancing capacitor means 16 connected between the first phase 6 and the third phase 18 of the transformer, and inductor means 20, connected between the second phase the second 8 and third phase mentioned 18 of the transformer 2. The compensation block 22 contains three times the condensing means 24 connected between the first phase 6 and the second phase 8 of the transformer 2. The first switch 10 branches, the first capacitor means 16, second condenser means 24 and inductor means 20 adapted to variation under load.

Although the invention is described with reference to specific embodiments of, this description should not be interpreted in a restrictive sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention will be obvious to experts in the art with reference to the description of the invention. Therefore, it is assumed that such modifications can be implemented without deviating from the essence or scope of the present invention.

1. The device (100) power supply for direct electric heating of a pipeline system, comprising:
three-phase transformer (2), adapted to support adenopathy load (4)connected between the first phase (6) and second phase (8) of the transformer (2), and referred to the transformer (2) contains at least one first switch (10) branches on the side (12) of the high voltage transformer (2);
block (14) balancing containing the first capacitor means (16)is connected between the first phase (6) and third phase (18) of the transformer, and inductor means (20)connected between the second phase (8) and third phase (18) mentioned transformer (2); and block (22) compensation containing the second capacitor means (24)connected between the first phase (6) and second phase (8) of the transformer (2),
the first switch (10) branches, the first capacitor means (16), the second capacitor means (24) and/or inductor means (20) adapted for variation under load.

2. The device power supply according to claim 1, additionally containing block (202), the control adapted to automatically control the voltage levels mentioned first switch (10) branches, capacity mentioned first capacitor means (16) and said second capacitor means (24) and mentioned inductance of the inductor means (20).

3. The device power supply according to claim 1, in which a three-phase transformer (2) further comprises at least one second switch (302, 304, 306) branches.

4. The device power supply according to any one of claims 1 to 3, in which the inductance of the inductor means (20) adapted to change under load using the third switch (21) branches.

5. The device power supply according to claim 1, in which automatic control of the capacity mentioned first condenser base is aqueous means (16) further comprises the step of switching at least one first additional capacitor (412, 414, 416), using the corresponding vacuum contactor(413, 415, 417).

6. The device power supply according to claim 1 or 5, in which automatic control of the capacity mentioned second capacitor means (24) further comprises the step of switching at least one of the second additional capacitor(422, 424, 426, 428, 430) using the appropriate vacuum contactor(423, 425, 427, 429, 431).

7. The device power supply according to claim 1, in which the transformer (2), first capacitor means (16), the second capacitor means (24), inductor means (20), the first additional capacitor (412, 414, 416), the second additional capacitor(422, 424, 426, 428, 430) and/or vacuum contactor(413, 415, 417, 423, 425, 427, 429, 431) are the corresponding components of the dry type.



 

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