FIELD OF THE INVENTION
[0001] Embodiments herein relate to the field of transformers. In particular, the embodiments
herein relate to handling transportation and assembling of a single phase transformer.
BACKGROUND
[0002] A power transformer is equipment used in an electric grid of a power system. Power
transformers transform voltage and current in order to transport and distribute electric
energy. Power transformers are in some cases very large and may not be possible to
transport to some locations. Because of this, it is useful if the size of the largest
transportable part of the transformer is reduced.
[0003] One way of solving this problem is that the transformer is disassembled at a factory
and transported to a site in pieces. The transformer is then assembled at the site.
This has the disadvantage that it needs, e.g. requires, facilities and resources on
site to carry out the assembly. It is also challenging to ensure the quality as it
is difficult to perform high voltage testing on site. High voltage testing after assembly
on site is normally not carried out with this technology.
[0004] Another way of solving the problem is to use parallel units. The power rating required
is divided in sever smaller units and each unit is shipped to the site. One disadvantage
of this is that each transformer requires its own installation on site, including
e.g. foundation, fire walls, and electrical connections, including bushings on the
transformers. This will drive both cost and footprint for transformers and for the
site.
[0005] Yet another approach to solve the problem for three-phase transformers is by using
a special three phase arrangement. A three phase unit is divided into three single
phase active parts, each transported to site in a separate tank. The three tanks are
located together on the same foundation at site and are normally connected together
with leads in oil ducts. The disadvantage of this solution is that it is does not
sufficiently reduce the transport size of the single phase tank, which may be too
large to transport. Also, if spare units are required, the full three phase transformer,
i.e., three single phase tanks, are normally needed for the spare units.
[0006] The present disclosure presents an improved viable solution of a method and transformer
arrangement.
SUMMARY
[0007] It is an object of embodiments herein to enhance transportation and assembling of
a single phase transformer.
[0008] According to an aspect the above-mentioned object is achieved by providing a method
performed by a transformer arrangement for handling transportation and assembling
of a single phase transformer. The single phase transformer is divided into two or
more active parts. The two or more active parts are transported to a site in at least
two separate tanks. The single phase transformer is then assembled by connecting the
tanks together electrically at the site, wherein the tanks are connected electrically
by one or more leads.
[0009] According to some embodiments, the tanks may be located on a same foundation at the
site.
[0010] According to some embodiments, at least two of the tanks may not be separated by
fire walls.
[0011] According to some embodiments, at least two of the tanks may have different electrical
properties.
[0012] According to some embodiments, at least one of the tanks may comprise a regulating
winding to regulate a voltage and at least one of the tanks does not comprise a regulating
winding.
[0013] According to some embodiments, at least two of the tanks may be connected in series.
[0014] According to some embodiments, at least two of the tanks may be connected in parallel.
[0015] According to some embodiments, the tanks may be connected on a primary side of the
single phase transformer and/or on secondary sides of the single phase transformer.
[0016] According to some embodiments, the tanks may share a same common cooling equipment.
[0017] According to some embodiments, at least two of the tanks may be mechanically connected.
According to some embodiments, the mechanical connection may be performed in such
a way that allows the at least two tanks to be transported in connected state at the
site.
[0018] According to some embodiments, at least one of the tanks may comprise a tertiary
winding and at least one of the tanks may not comprise a tertiary winding.
[0019] According to another aspect the object is also achieved by providing a transformer
arrangement. The transformer arrangement comprises a single phase transformer and
two or more tanks. The transformer arrangement is configured to divide the single
phase transformer into two or more active parts and transport the two or more active
parts to a site in at least two separate tanks. The transformer arrangement is further
configured to assemble the single phase transformer by connecting the tanks together
electrically at the site, wherein the tanks are connected electrically by one or more
leads.
[0020] According to yet another aspect the object is also achieved by providing a single
phase transformer. The single phase transformer is configured to be divided into two
or more active parts, wherein the two or more active parts are transported to a site
in at least two separate tanks. The single phase transformer is further configured
to be assembled by connecting the tanks together at the site, and wherein the tanks
are connected electrically by one or more leads.
[0021] Embodiments herein are based on the realisation that by dividing the single phase
transformer into at least two active parts which are transported to the site in at
least two separate tanks, the transportation size of the single phase transformer
is significantly reduced. Furthermore, as the single phase transformer then can be
assembled by connecting the tanks together electrically at the site the assembly is
handled in a more efficient manner. Thereby the transportation and assembling of a
single phase transformer is enhanced.
BRIEF DESCRIPTION OF THE FIGURES
[0022] Further technical features of the invention will become apparent through the following
description of one or several exemplary embodiments given with reference to the appended
figures, where:
- Fig. 1
- is a schematic overview depicting a transformer arrangement, according to embodiments
herein;
- Fig. 2
- is a flowchart depicting a method according to embodiments herein;
- Fig. 3
- is a schematic overview depicting a transformer arrangement, according to some embodiments
herein; and
- Fig. 4
- is a schematic overview according to some embodiments.
[0023] It should be noted that the drawings have not necessarily been drawn to scale and
that the dimensions of certain elements may have been exaggerated for the sake of
clarity.
DETAILED DESCRIPTION
[0024] A transformer arrangement 20 according to embodiments herein is illustrated in
Fig. 1. The transformer arrangement 20 is configured to divide, e.g. separate, a single phase
transformer into two or more active parts 14. The active part 14 of the single phase
transformer when used herein is the core, the windings, and the electrical insulation
between the windings of the single phase transformer. The two active parts 14 may
be placed in at least two separate tanks 10, e.g. transformer tanks. The at least
two separate tanks 10 are connected electrically by one or more leads and may be mechanically
attached together. The two or more active parts 14 are then transported to a site
in the at least two separate tanks 10. When at the site, the single phase transformer
is assembled by connecting the tanks 10 together electrically. If a voltage regulating
system is used in the transformer arrangement it may be possible to enable it by using
a common On-Load Tap Changer (OLTC) or a common OLTC drive unit. This means that at
least some tanks 10, may be reduced in size and that the number of components can
be reduced. According to some embodiments, a fully assembled spare single phase unit
comprising the at least two separate tanks 10 with the active parts 14, installed
at the site, may be provided at the site as a backup. Access to a fully assembled
spare unit reduces the replacement time in case of a failure in one of the single
phase transformers that are in operation.
[0025] The method actions for handling transportation and assembling of a single phase transformer,
according to embodiments herein, will now be described with reference to a flowchart
depicted in Fig. 2. The actions do not have to be taken in the order stated below
but may be taken in any suitable order.
Action 201.
[0026] To significantly reduce the transportation size of the single phase transformer,
the single phase transformer is first divided into two or more active parts 14. Thereby,
certain transportation modes may be enabled. Accordingly, transportation of the single
phase transformer can be significantly simplified, leading to reduced costs. Furthermore,
in some cases, transport of a full size single phase unit may not be possible at all
and measure to reduce the size is necessary.
Action 202.
[0027] The two or more active parts 14 are then transported to a site in at least two separate
tanks 10. The at least two tanks 10 with the active parts 14 may be seen as a unit
such as a transportation unit and may be referred to as a single phase unit. The tanks
10 may be transported by one or more vehicles, such as lorries.
[0028] According to some embodiments, at least two of the tanks 10 may have different electrical
properties. This is advantageous/useful because it may, under certain conditions,
allow for a decrease in size of the largest transportable part or it may, under certain
conditions, allow for a decrease in total number of active parts and tanks. In some
conditions, it may also reduce the cost of the single phase transformers as the active
parts 14 can be more specialised. Furthermore, the reliability of the single phase
units may be improved because fewer components, for example regulating windings, tertiary
windings and/or tap changers, may be required with less overall risk for failures
as a consequence.
[0029] At least two of the tanks 10 may be mechanically connected. The mechanical connection
may be performed in such a way that allows the at least two tanks 10 to be transported
in connected state at the site, i.e. inside the site. Thus, the at least two of the
tanks 10 may not be connected during transport to the site, but they may be moved
connected within the site. This is a great advantage if needing to replace a unit
in operation with a fully assembled spare unit in short time. This is a great advantage
if needing to replace a unit in operation with a spare unit. The spare unit can in
such case be fully assembled prior to the replacement procedure which will reduce
the time to put the spare unit into operation.
[0030] According to some embodiments, at least one of the tanks 10 may comprise a regulating
winding to regulate a voltage and at least one of the tanks 10 does not comprise a
regulating winding. This is advantageous/useful because it may, under certain conditions,
allow for a decrease in size of the largest transportable part or it may, under certain
conditions, allow for a decrease in total number of active parts and tanks. Furthermore,
the reliability of the single phase units may be improved because fewer components,
such as tap changers and regulating windings, are required. According to some embodiments,
the at least one of the tanks 10 that comprises the regulating winding may not be
connected to a primary side or secondary side of the transformer.
[0031] According to some embodiments, the at least one of the tanks 10 that comprises the
regulating winding may be connected to one of the primary side and the secondary side,
but not connected to both. According to some embodiments, the at least one of the
tanks 10 that comprises the regulating winding may be connected to both the primary
side and the secondary side.
[0032] According to some embodiments, at least two of the tanks 10 may be connected in series.
This is advantageous because it may, under certain conditions, allow for a decrease
in size of the largest transportable part or it may, under certain conditions, allow
for a decrease in total number of active parts and tanks. Furthermore, the reliability
of the single phase units may be improved, and cost may be reduced because some parts
may be exposed to a lower voltage level.
[0033] According to some embodiments, at least two of the tanks 10 may be connected in parallel.
This is advantageous because it allows for less complex design as each part can be
made with the same or similar design. Furthermore, in some implementations the reliability
can be increased as some of the parallel parts may be operated even with failures
on other parallel parts. The at least two of the tanks 10 may be connected both in
parallel and in series.
[0034] According to some embodiments, the tanks 10 may be connected on a primary side, of
the transformer. This is advantageous because it allows for a single connection towards
the external primary voltage system, which may reduce overall size and cost of the
transformer arrangement 20, including size of transformer tanks 10, transformer foundation
and transformer booth. Furthermore it may improve the reliability of the single phase
transformer because fewer components, for example bushings, may be required.
[0035] According to some embodiments, the tanks 10 may be connected on secondary sides of
the transformer. This is advantageous because it allows for a single connection towards
the external secondary voltage system, which may reduce overall size and cost of the
transformer arrangement 20, including size of transformer tanks 10 and transformer
booth. Furthermore it may improve the reliability of the transformer because fewer
components, for example bushings, may be required.
[0036] According to some embodiments, the tanks 10 may be connected on the primary side
and the secondary sides of the transformer. This is advantageous because it allows
for a single connection towards the external primary and secondary voltage system,
which may reduce overall size and cost of the transformer arrangement, including size
of transformer tanks 10 and transformer booth. Furthermore it may improve the reliability
of the transformer because few components, for example bushings, is required.
[0037] Thus, the tanks 10 may be connected on the primary side of the single phase transformer
and/or on secondary sides of the single phase transformer.
[0038] According to some embodiments, at least two of the tanks 10 may comprise a separate
cooling equipment and/or at least two of the tanks 10 may comprise a common cooling
equipment. According to some embodiments, the tanks 10 may share a same common cooling
equipment. This is advantageous because the overall size, cost and complexity of the
transformer arrangement, including cooling control and size of the transformer booth
may be reduced.
[0039] According to some embodiments, at least one of the tanks 10 may comprise a tertiary
winding and at least one of the tanks 10 may not comprise a tertiary winding.
[0040] According to some embodiments, the tanks 10 may be aligned in a row and a three phase
bank may be constructed by aligning the single phase side by side such that the rows
are parallel to each other.
[0041] According to some embodiments, the tanks 10 are aligned side by side with the long
side of the tanks facing each other.
[0042] According to some embodiments, at least one of the tanks 10 may comprise a tertiary
winding and at least one of the tanks 10 may not comprise the tertiary winding.
Action 203.
[0043] The single phase transformer is then assembled by connecting the tanks 10 together
electrically at the site, wherein the tanks 10 are connected electrically by one or
more leads, e.g. in oil or fluid.
[0044] According to some embodiments, the tanks 10 may be located, e.g. connected together
electrically, on a same foundation at the site. This is advantageous because it reduces
the required footprint and cost of civil construction at site. At least two of the
tanks 10 may not be separated by fire walls
[0045] By adopting the embodiments herein as described above, the size and weight of the
single phase transformer to be transported, e.g. each transport unit, can be significantly
reduced.
[0046] Embodiments herein such as mentioned above will now be further described and exemplified.
The text below is applicable to and may be combined with any suitable embodiment described
above.
[0047] A transformer arrangement 20 according to some embodiments is illustrated in
Fig. 3. At least two tanks 10 may be mechanically attached together, are connected electrically
in oil by one or more leads, e.g. in oil or fluid ducts, and are transported to the
site. At least one of the tanks 10 may comprise a regulating winding to regulate a
voltage and at least one of the tanks 10 may not comprise a regulating winding. The
at least one of the tanks 10 may comprise the regulating winding to regulate the voltage
is marked with an X in Fig. 3. Accordingly, at least one tank 10 may contain regulation.
At least one of the tanks 10 may comprise a tertiary winding to supply power to a
separate voltage system and at least one of the tanks 10 may not comprise a tertiary
winding. Providing tertiary windings in less than all tanks may reduce the cost because
less total number of tertiary windings are required, which may also improve the reliability
of the single phase transformer. Fig. 3 shows four tanks 10 connected in parallel,
wherein three of the tanks 10 may be connected in parallel as main single phase transformer,
and wherein all four tanks 10 may be referred to as a single phase unit.
[0048] A transformer arrangement 20 according to some embodiments is illustrated in
Fig. 4. The figure shows an example with three series connected units, e.g. three series
connected tanks 10 comprising the active parts 14 of the single phase transformer.
However, it does not necessarily have to be three unit in series, it may be any number
from two and above. The three tanks 10 may be connected mechanically and have electrical
connection in oil. In some implementations, for example a Y connected transformer,
the series connected units have advancingly lower voltage. According to one implementation,
the tap changer is located in the unit with the lowest voltage.
[0049] It is to be noted that any feature of any of the aspects may be applied to any other
aspect, wherever appropriate. Likewise, any advantage of any of the aspects may apply
to any of the other aspects.
[0050] Generally, all terms used in the claims are to be interpreted according to their
ordinary meaning in the technical field, unless explicitly defined otherwise herein.
All references to "a/an/the element, apparatus, component, means, step, etc." are
to be interpreted openly as referring to at least one instance of the element, apparatus,
component, means, step, etc., unless explicitly stated otherwise. The steps of any
method disclosed herein do not have to be performed in the exact order disclosed,
unless explicitly stated. The use of "first", "second" etc. for different features/components
of the present disclosure are only intended to distinguish the features/components
from other similar features/components and not to impart any order or hierarchy to
the features/components.
[0051] It will be appreciated that the foregoing description and the accompanying drawings
represent non-limiting examples of the method taught herein. As such, techniques taught
herein are not limited by the foregoing description and accompanying drawings. Instead,
the embodiments herein are limited only by the following claims and their legal equivalents.
1. Method for handling transportation and assembling of a single phase transformer, wherein
the method comprises:
dividing (201) the single phase transformer into two or more active parts (14);
transporting (202) the two or more active parts (14) to a site in at least two separate tanks
(10); and
assembling (203) the single phase transformer by connecting the tanks (10) together electrically
at the site, wherein the tanks (10) are connected electrically by one or more leads
2. The method according to claim 1, wherein the tanks (10) are located on a same foundation
at the site.
3. The method according to claim 1 or 2, wherein at least two of the tanks (10) are not
separated by fire walls.
4. The method according to any one of claims 1-3 , wherein at least two of the tanks
(10) have different electrical properties.
5. The method according to any one of claims 1-4, wherein at least one of the tanks (10)
comprises a regulating winding to regulate a voltage and at least one of the tanks
(10) does not comprise a regulating winding.
6. The method according to any one of claims 1-5, wherein at least two of the tanks (10)
are connected in series.
7. The method according to any one of claims 1-5, wherein at least two of the tanks (10)
are connected in parallel.
8. The method according to any one of claims 1-7, wherein the tanks (10) are connected
on a primary side of the single phase transformer and/or on secondary sides of the
single phase transformer.
9. The method according to any one of claims 1-8, wherein at least two of the tanks (10)
comprise a separate cooling equipment and/or at least two of the tanks (10) comprise
a common cooling equipment.
10. The method according to any one of claims 1-9, wherein at least two of the tanks (10)
are mechanically connected.
11. The method according to claim 10, wherein the mechanical connection is performed in
such a way that allows the at least two tanks (10) to be transported in connected
state at the site.
12. The method according to any one of claims 1-11, wherein at least one of the tanks
(10) comprises a tertiary winding and at least one of the tanks (10) does not comprise
a tertiary winding.
13. A transformer arrangement comprising a single phase transformer and two or more tanks
(10), wherein the transformer arrangement is configured to:
divide the single phase transformer into two or more active parts (14);
transport the two or more active parts (14) to a site in at least two separate tanks
(10); and
assemble the single phase transformer by connecting the tanks (10) together electrically
at the site, wherein the tanks (10) are connected electrically by one or more leads.
14. The transformer arrangement according to claim 13, wherein the transformer arrangement
is configured to perform the method according to any one of claims 2-12.
15. A single phase transformer, configured to be divided into two or more active parts
(14), wherein the two or more active parts (14) are transported to a site in at least
two separate tanks (10), and wherein the single phase transformer is assembled by
connecting the tanks (10) together at the site, and wherein the tanks (10) are connected
electrically by one or more leads.