GB2511506A - Cooled flameproof power supply apparatus - Google Patents

Abstract

A cooled flameproof power supply apparatus 10 comprises a flameproof enclosure 12 housing a power unit 14 to provide A power supply to a device external to the enclosure. A cooling liquid conduit 26 is provided adjacent the power unit to remove heat from the unit. A flameproof connector 28 provides communication of cooling liquid through a wall of the enclosure, the flameproof connector communicating with the cooling liquid conduit. In an embodiment input and output cabling is included. In a further embodiment a breather is included which permits pressure equalization. In another embodiment positive pressure is maintained within the enclosure. The power supply may be an electric motor.

Description

I

COOLED FLAMEPROOF POWER SUPPLY APPARATUS

HELD OF THE INVENTION

The present invenfion relates to providing coong for electrical equipment deployed in explosive environments, and in particular, but not exclusively, to c.oong provided for explosionprotected encbsures containing heatgenerating electrical equipment.

BACKGROUND TO THE INVEN1ION

Electric equipment provided wRhin potentiaHy explosive environments, for example, on o or gas platforms or the ke, has the potenti to generete a spark and cause an explosion. Further, excess heat generated by the eectric& equipment can also potenUaHy bigger an explosion.

Accordingly, it is necessary to protect such electrical equipment (usually according to a certified standard), GeneraHy, the more hazardous the environment, the higher level of testing required before the equipment is permitted for use within that environment. For example, in the European Economic Area (EEA) products intended for use in explosive environments should presently compiy with AlEX Directive 94/9/EC. Other standards exist which similarly define safety standards in explosive environments, for example, via the IECEx scheme administered by the International Electrotechnical Commission (lEG).

Presently, several approaches are routinely used for preventing and/or containing flames or explosions caused by electrical equipment. In one approach, electrical equipment can be contained within a flameproof enclosure, GeneraVy, flameproof enclosures are made from materials such as steel or aluminium alloy due to theft high strength. In another approach, electrical equipment can be contained within a pressurised enclosure, wherein pressure is maintained by a constant supply of air which ensures that explosive gases or the like are prevented from entering the enclosure. This requires an air supply which is free from any explosive constituents, which may be practicafly difficult and costly to implement.

Oil and gas rigs often feature reeling equipment for deploying and reeling flexible elongate members. One such reelable member is the TMumbillcaL" used for conducting subsea operations from the surface. A typical umbilical may comprise electric cables, hydrauc hoses and tubes or fibre optics cables. Some reoUng eqthpment is driven by pneumaflc or hydrauUc motors, each requiring a specialised suppiy of compressed air or hydrauUc fluid, respectively. However, there may be difficulty in providing a suitable compressed air or hydraulic fluid supply. Also, these systems may only provide for a Umited level of control in situations where changes of tension in an umbilical are encountered, for example, on a floatIng offshore platform or vessel where changes in sea level cause tension changes in the umbUical.

Usually, a storm loop is provided for deaUng with such tension changes in the umbUical and thus requires a complex umbilical arrangement.

An example of equipment for recUng an umbilical is disclosed in WO 20091131465 Al (Advantec Winch Systems AS), wherein a reel with a rotatable reeUng device and replaceable drum is described.

An electric supply is generaUy more readily available. Electric motors often require a specielised power supply, for example, a variable frequency, voltage or current supply, or the like, such as that provided by a variable frequency drive, variable speed drive, inverter drive or the like. However, as with any electrical equipment, a power unit providing that specialised power supply has a disadvantage in that an electric spark may be generaled. Therefore the power unit must be isoted if it is intended to be used in eKplosive environments. This isolation may be achieved by placing the power unit within a suitable environment, for example, in an area that is not considered to be hazardous by running power cabling from that area to the explosive environment in which the electric motor is located. This option may not be possible if no safe area exists or it is not practicable to proide the necessary power cabng. An alternative option is to contain the power unit wfthin an explosion protected power unit endosure, An example of an exploonproof power supply enclosure is cflaclosed in US 6,900,565 62 (Preston, J.), wherein the apparatus comprises an explosionproof shell, and an electronic motor controer for external motor controL Coong is achieved via sod akiminium plates to conduct heat from the motor controfler to outside the shelL During operaVon, the power unit produces heat which must not exceed a specified value in order to prevent abnormal operation or faUure of the power unit.

Further, if that heat causes the outer surface temperature of the power unit enclosure to exceed a further specified value, there exists a risk of explosion.

The cuter surface temperature of any power unit enclosure varies according to at east the ambient envfronrnental temperature, the rate of heat produced by the power unit and any other equipment contained within the power unit enclosure, and the rate of heat dissipated by the power unit enclosure. Accordingly, tor a given size and configuration of the power unit enclosure, a power unit may be configured to provide ectricS power not exceeding a certain leveL Therefore, power supplied by the power unit is limited by the power unit enclosure size and conUguration.

SUMMARY OF THE iNVENTION

According to a first aspect of the present invention there is prcMded a cooled flameproof power supply apparatus comprising: a flameproof enclosure; a power unit to provide a specialised power suppy to a device external to the enclosure, wherein the enclosure houses the power unit; a cooling quid conduit adjacent the power unit and configured to remove heat therefrom; and a flameproof connector configured to provide communication of coding liquid through a wali of the enclosure, wherein the flameproof connector communicates with the. cooling liquid conduit, In use, the apparatus permits operation of the power unit within an explosive environment, for example, such as on an ofFshore cl and gas patForm, or the like, If the power unit creates a spark, then that spark should be contained within the enclosure, thereby preventing an explosion from spreading outside the enclosure.

Similarly, if any flammable or explosive gases enter the enclosure, any resufting flame and/or explosion should be contained within the enclosure. However, during normal operation the power unit generates heat. The heat generated may cause a rise in temperature which may result in abnormal operation, power unit failure, or if 2.0 an outer surface of the enclosure exceeds safe temperature limits, an explosion may ensue. The apparatus may be confIgured to remove heat from the power unit, thereby preventing a rise in temperature sufficient to cause taflure or an expiosion The apparatus can be configured to be plug and play," wherein the apparatus only requires provision of a standard or nonspscialised electrical power suppy.

$5 Embodiments of the invention may offer increased levels of monitoring and control of motofrdriven devices, for example, reeling equipment.

The connector may provide a communication path between inside and outside the enclosure, The connector may comprise a passageway configured to permit communication of air, gas and/or liquid therethrough. The passageway may permit communication of coong liquid therethrough. The passageway may arrest progression of any flame and/or hot gas therethrough, wherein the passageway may at least partiaUy cool any flame and/or hot gas which may progress therethrough such that sd any flame and/or hot gas may be extinguished and/or cooled by an amount sufficient to prevent ignftion of any explosrve matter situated adjacent the connector, and wherein hot gas may be defined as being sufficiently capable of causing en explosion by v1ue of its temperature.

The enclosure may comprise at least one harrier gland to permit input power cahng and output power cabling to be run through a wall of the enclosure, wherein the input power cabling may be configured to communicate input power from a power source external from the enclosure to power the power unit and the output power cabling may ho configured to communicate the specialised power supply from the power unit to the device, wherein the barrier gland prevents any flame and/or hot gas from progressing therethrough, The at east one barrier gland may permit control cabftng to be run through a wall of the enclosure, wherein the control cabling may be conFigured to control the power unit.

The apparatus may comprise a conduit circuit comprising an inner conduit circuit defined as being part of the conduit circuit inside the enclosure and an outer conduit circuit defined as being part of the conduit circuit outside the enclosure.

The apparatus may comprise an adaptor configured to attach part of the conduit circuit to the connector. The apparatus may comprise a plurality of adaptors for attaching parts of the conduit circuit to the connector.

The apparatus may comprise a plurality of connectors. The apparatus may comprise a first connector and a second connector. The first connector may be configured as an inlet. The second connector may be configured as an outlet. The apparatus may comprise one or more connectors configured as inlets, The apparatus may comprise one or more connectors configured as outlets, Where there are one or more connectors the rate of flow of' liquid may be increased therethrough. At least one junchon, for example, a Thunction may be provided to connect more than one connector to the conduit circuit, The apparatus may be configured to communicate coong liquid from the outer conduit circuit to the inner conduit circuit via the inlet The apparatus may be configured to communicate cooling liquid from the inner conduit circuit to the outer conduit circuit via the outlet.

IC) The enclosure may comprise a further connector provided separately from the conduit circuit. The further connector may be configured to operate as a breather to permit gas/air pressure equalisation between inSe and outside the enclosure, wherein gas/air pressure equaUsation prevents buil&up of pressure within the enclosure, A plurality of further connectors may be provided as breathers.

The further connector may be provided to permit purging of air and/or gas from within the enclosure, wherein the enclosure may be configured to maintain a positive pressure therein, for example, as part of a purging system configured to prevent outside air and/or gases from entering the enclosure.

The further connector may permit drainage of cooling liquid that may have leaked from any part of the apparatus contained within the enclosure.

The apparatus may comprise a heat sink, The heat sink may be in communication with the conduit and be configured to remove heat generated by the power unit, wherein the heat sink may be further configured to transfer that heat into cooling liquid being communicated within the condu adjacent the power unit, wherein the conduit circuit communicates cooling liquid to and from the conduit adjacent the power unit. Heat may be removed from inside the enclosure, wherein cooling liquid may communicate that heat from inside the enclosure to outside the enclosure via the outlet of the conduit circuit, The apparatus may comprise a heat dissipation apparatus, for example, a heat exchanger positioned outside the enclosure, wherein the heat dissipation apparatus may be configured to remove heat from cooling quid and dissipate that heat away from the enclosure.

The enclosure may be dimensioned to prevent an unsafe bu&up of temperature inside the enc4osure and/or on an outer surface of the encbsure, wherein dimensions of the enclosure and other parameters, including any material used to construct the encosure, or the like, may be appropriate to house the power unit, wherein the power unit may be configured to produce an eectrical output power appropriate for any design parameters associated with the enclosure.

The power unit may produce electrical output power in the region of 37 kW, or any other electrical power output of that order of magnitude.

The enclosure may be dimensioned according to the electrical output power, wherein for an electrical output power of 37 kW, the enclosure may have approximate dimensions of ixO7x0.4 metres, wherein the apparatus may he required to maintain the enclosure at a sufficiently low temperature to permit operation of the power urüt and/or prevent an exploon from occurring.

The power unit may be utilised for speciahsed operation of the device, wherein the specialised power suppiy provided by the power unit may be configured to controilably adjust at east one electrical parameter, for example. current, voage, frequency, or any other related electrical parameter.

The power unit may include, for example, a variable frequency drive, variable speed drive, inverter drive, or the ke, The power unit may be configured to be controlled externally by a control unit, for example, by a computer situated external to the enclosure, wherein the control unit communicates with the power unit via, a wired and/or wireless data connection.

The power unit may be configured to be controed automaticay, for example, using commands from the control unit. The power unit may be configured to be controfled manuaily, for example, by a person. The power unit may be configured to be controiled semiautomaticaHy, for example, by a person operating the control unit, wherein the control unit may be configured to assist the person in controlling the power unit.

The device may comprise a component which requires the specialised power supply, wherein the component may be configured to be controlled end/or operated by the speclailsed power supply.

The component may include, kw example, an electric motor. The power unit may be conIiaured to control at least one rotational parameter associated with a rotationai drive movement of the electric motor, including: angular positioning, angular speed, angular acceleration, timing, torque, or the like.

The device may be controed as pad of a feedback loop, wherein the electric motor may be configured to respond to feedback From the device, The component, for example, the electric motor may be configured to drive the device, for example, a reeilng device configured to reel an umbilical.

The reellng device may comprise an umbifical configured to be reeled by the reeling device, wherein the umbilical may be configured to he attached to an object for performing operations either under water or above water. The electric motor may control deployment of the umbilical from the reeilng device. The electric motor may control at east one reeling device parameter associated with the umbiilcal, including: positioning, timing, speed, acceleration, deceleration, umbical tension, dutch control, gearing, or the ike.

The reeng device may be configured in a reeling feedback loop to control parameters associated with reeling the umbfiicaL The reeling device may be configured in the reeling feedback loop to control positioning of the umbilical in a given location and to accurately re*position the umbilical in the given location, The reeling device may be configured as part of a tension feedback loop to compensate for tension changes in the umbilical, In this manner any sensitive equipment provided within the umbilical can be protecLed from adverse changes ri umbliic& tension durftig the course of use.

BRIEF DESCRIP1]ON OF THE DRAWINGS These and other aspects of the present invention will now be described, by way of example oniy, with reference to the accompanying drawings, in which: Figure 1 is a front view of a cooled flameproof power supply apparatus, shown without the enclosure door; and Figure 2 is a first aS secfion through the apparatus of Figure 1 showIng inlet connections; and Figure 3 is a second side section through the apparatus of Figure 1 showing outlet connections; and Figure 4 is a view from below of the apparatus of Figure 1; and Figure 5(&e) are schematic representations of the apparatus as part of a control system, wherein each of Figures 5(ae) connect to each other as indicated by dashed lines: and Figure 8 is a diagrammatic illustration of a section of a flameproof connector; and Fgure 7 is a simplified representation of a reeling apparatus, wherein the reeling apparatus is operated by an electric motor controlled by the apparatus.

DETPJLED DESCRIPTION OTHE DRAWINGS

In Figures 1 to 4 a cooled flameproof power supply apparatus is shown in various views as outlined in the brief description. Figure 5(ae) shows split views of a control system for controliing the apparatus, wherein referenced dotted lines indicate how the split views converge.

In reference to Figures 1-6, an apparatus 10 is shown comprising an enclosure 12 which is fiameproof such that the enclosure 12 is capable of containing any adverse effects of any flame and/or hot gas produced therein without compron1ng the integrity of the enclosure 12, and particularly to prevent the flame and/or hot gas from igniting any explosive gas, vapour or Uquid situated outside the enclosure 12. The enclosure 12 comprises a material of sufficient strength to contain 6 an explosion resulting from ignited gas, vapour and/or iquid; the material including for example, strengthened plastic/polymer or metal including aluminium, steel, metal aoya, or the hke. A skilled person would understand that any suitable material could be used for constructing the enclosure. The enclosure 12 supports a power unit 14 adjacent an enclosure wafi 16 by use of mounts 18 and a support plate 20. The power unit 14 is positioned at an appropriate safe location within the enclosure 12, wherein the safe location can be any position which decreases risk of excess build up of heat and/or an explosion occurring. In this embodiment the mounts 18 and support plate 20 support the power unit 14 such that the power unit 14 is not in abutment with the enclosure wa 1$ to prevent transfer of heat by direct conduction therebetween.

A heatsink 22 removes heat from the power urut 14 by direct conduction. In the described embodiment the heatsink 22 is shown at the base of the power unit 14, however, the heatsink 22 may be placed adjacent and/or within the power unit 14, providing the heatsink 22 serves to remove heat from the power unit 14.

A cooUng apparatus 24 comprises a conduit circuft 26 which permits coong liquid to be communicated therethrough, for example, by being pumped around the conduit circuit 26 using a pump 27 (Figure Sd). coong liquid may include any non flammable, nondamaging Uquid suitable for use in the conduit circuit 26, for example, water, waterglycol solutions, saline water sokitions, or the like. The conduit 26 circuit 26 passes through and/or adjacent the heatsink 22 to permit communication of cooling liquid through and/or adcent the heatsink 22. The Uquid 4'ch passes through and/or adjacent he heatsink 22 removes heat therefrom. ii

The coofing apparatus 24 pumps coollng quid through the conduit circuit 26 from outside the endosure 12 to inside the enclosure 12 via two inlet connectors 28.

Any appropriate number of inlet connectors 28 could be used to provide sufficient rate of communication of coong fluid through the connectors 28, given that indMdual connectors may restrict quid communication therethrough. The cooling apparatus 24 distributes the cooling liquid through the conduit circuit 26 in a first direction indicated by arrow 30 towards the heatsink 22. The cooling apparatus 24 distributes the cooling liquid which has removed heat from the heatsink 22 to outside the enclosure 12 via two outlet connectors 32 in a second direction 34. Any appropriate number of outlet connectors 32 could be used to provide sufficient rate of communication of cooling fluid through the connectors 32, given that the connectors may restrict flow of liquid therethrough, Where there are more than one inlet or outlet connectors,, there is provided at least one Tshaped conduit junction 33 to connect the conduit circuit to the more than one inlet or outlet connectors in order to circulate cooling fluid through ¶5 the conduit circuit, Other unction types are also available for providing the same connectivity as the Tshaped conduit junction 33, The inlet and outlet connectors are configured to be situated n apertures 35 drilled or otherwse formed in the enclosure tde wall 16. The cooling liquid which has removed heat is subsequently directed towards a heat exchanger 3$ for dissipation of the heat in a safe location outside the enclosure 12. The heat exchanger 36 removes heat from the cooling liquid and redistributes the cooling liquid back into the enclosure via the conduit circuit 26 for further cooling of the power unit 14. In this manner, cooling liquid is circulated through the conduit circuit 26.

The conduit circuit 26 comprises at least one inlet connector 28 and at least one outlet connector 32, wherein the inlet and outlet connectors 28 and 32 are typically identical. The inlet and outlet connectors 28 and 32 permit communication of cooling liquid therethrough. The inlet and outlet connectors 28 and 32 prevent progression of any flame and/or hot gas therethrough, instead, cooting said flame and/or hot gas dwing its progression therethrough. in one such type of connector, the inet and outlet connectors 28 and 32 comprise a structure configured to inhibit direct communication al any air, gas and/or liquid between inside and outside the enclosure, The inlet and outlet connectors 28 and 32 can further comprise at least one passageway 38 (Figure 6) configured to permit communication of air, gas and/or liquid therethrough in such a way that said communication is in an indirect manner. In this indirect manner, should any flame and/or hot gas progress through the passageway 38 the flame and/or hot gas shoidd cool down by the time it has passed all the way through the passageway 38. The connectors 28 and 32 are required in order to teed the conduit circuit 26 through the enchaure wall 16. An opening made in the enclosure wa 1$ to accommodate the conduit circuit 26 must be plugged by a connector which permits flow of coong liquid therethrough and arrests progression of any flame and/or gas therethrough. The connectors 28 and 32 are attached to the conduit circuit 26 using adaptors 40 to provide a liquid4ight connection.

A further, third connector 42 may optionay be included as a separate entity from the conduit circuit 26 to act as a breather to equalise any pressure differential between inside and outside the enclosure 12. The third connector may he conflgured act as a drain to permit any liquid which leaks from the conduit circuit 26 to safely exit the enclosure 12.

A power output indicated by lines 46 depicts cabling running from the power unit 14 inside the enclosure 12 to operate any dece located outside the enclosure 12 requiring such power output. Any power cables associated with the power output 46 are run through the enclosure waH 16 via barrier glands 48 located within the enclosure side wail 1$ and are configured to permit cabng to be run through the enclosure waU 16 and are further configured to prevent a flame and/or hot gas from progressing therethrough. The barrier glands 46 are situated within apertures 35 in the enclosure side wall 16. Further, control cabling configured to communicate commands from a control unit and/or responses from the power unit can be run through the enclosure wall 18 via a barrier gland. Nternativeiy, ali cabling could be run through a single hanler gland.

Figures 5(a-e) show split views or a simplified representation of a control system comprising the power unit 14 housed within the enclosure 12. Dashed lines 51(a*-e) indicate how the split views are connected. A conttl unit 52 is configured to control the power unit 14, the cooling apparatus 24 and/or a device 53 which requires a specialised power supply, as provided by the power unit 14. The control unit 52 can be operated in a number of ways to control the power unit 14., the cooling apparatus 24 and/or the device 53. For example, the control unit could he configured to he ID operated autornatioaliy, semiautomaticaHv or rnanuay, wherein a person operating the unit 52 would have different levels of control over different devices by permitting a rnicrocontroer 55 (or the like.) to issue commands to the power unit 14, the cooling apparatus 24 and/or the device 53. This would be useful where the person wishes to assume control over the device 53 but does not wish to be concerned with specific parameters requiring normal operation. The control unit 52 couki be configured to connect to the power unit 14, the cooling apparatus 24 and/or the device 53 using either a wired and/or wireless connection; in Figures 5(ae) wired connecons for providing power and/or commands between the power unit 14, cooling apparatus 24 and device 53 are indicated by lines 57.

Power idr the control unit 52, cooling apparatus 24 and power unit 12 can be obtained from the main power supply 54, wherein the main power supply 54 is passed into the enclosure 12 via harrier glands 48 situated within apertures 35 in the enclosure side wail 18. Flow of the cooling liquid is indicated by arrow 30 from the heat exchanger 36 of the cooling apparatus 24 to the power unit 14. Arrow 34 indicates flow of cooling liquid from the power unit 14 to the heat exchanger 36 of the cooling apparatus 24. As explained previously, heat is removed from the power unit 14 using the cooling liquid and distributed outside the enclosure 12 via the heat exchanger 36.

In the present ernhothment the power unit 14 comprises a variable frequency drive configured to provide the specalised power supply, wherein the voltage and current provided by the power unit 14 may be configured to be varied in at least frequency and amphtude. in same embodiments other tpes of power units may be used to provide the same or similar speciased power supply. In particular, the power unit 14 may be configured to controably adjust at east one elecifical parameter, fOr example, current, voltage, frequency, waveform, and/or any other related electrical parameter.

In providing a speciased power supply, the power unit 14 generates heat depending on the total electrical output power of the power unit 14. As the power urüt 14 is situated inside an endosure, the heat generated may cause a temperature rise in the enclosure 12. Further, if left unchecked such a temperature rise may cause incorrect/poor operation of the power unit 14, or even cause an increase of surface temperature of the endosure 12. Accordingly, any temperature change depends on at east the rate of total electrical output power generated by the power unit 14 and the rate of heat dissipation by the enclosure side wa 16. The temperature change is further affected by the dimensions and material of the enclosure 12, positioning of the power unrt 14 inside the enclosure 12 and the ambient temperature inside and outside the enclosure 12, among other factors. Therefore, the dimensions of the enclosure 12 should be suitably chosen so as to not resuit in a substantial rise of temperature. In prncipie, it is possible to increase the dimensions of any enclosure relative to the power unit 14 such that the rate of heat dissipation by the total surface area of said enclosure is sufficient to maintain a sLrfficently low temperature inside and on the said enclosure, However, this is not a practicable option where space is at a premium, as is often the case for example, on oH and gas offshore platforms.

Therefore, the cooling apparatus 24 has several interThnked purposes. Firstly, the cooling apparatus 24 serves to prevent an undesirable increase in temperature inside the enclosure 12 to permit normal operation of the power unit 14 which would iS otherwise be affected by an unacceptably high operating temperature. Secondly, the coding apparatus 24 serves to prevent a temperature increase on an outer surface of the enclosure wa 18, which would otherwise increase the prohabHity of an explosion within any explosive envimnment, such as those on ed or gas offshore platforms. Thirdly, the cooling apparatus 24 serves to permit use of a smaHer dimensioned enclosure 12, than would otherwise be the case, hence permitting use of the power unit 14 in places where there is Urnited space available, such as the case on oil or gas offshore platforms. For the present embodiment, a typical total electrical output power of around 37 kW would be permitted in an enclosure of dimensions lxO,YxO,4 metres, Such a combination of outptrt power and dimensions would not normay provide the advantages offered by the present invention.

However, a skilled person would understand that the invention has utiUty in other combinations of electrica output power and dimensions.

Figure $ shows an expanded representative view of one of the connectors in Figures ito 5 with fluid flowing in a direction 49. In addition to the features already described, further features are described which are useful to the operation of any connector 28, 32 or 42 in the present embodiment. The connector comprises bulkheads 50, which are configured to prevent direct communication of air, gas and/or liquid through the connector. The bulkheads 50 are further configured to permit indirect or restricted communcaton of air, gas and/or liquid through the connector 28 via passageways 38. The passageways 38 are configured such that any flame and/or hot gas generated adiacent one side of the connector which progresses through the passegeways 38 is cooled down to such an extent that upon exiting the passageways 38, said flame and/or hot gas cannot cause a fire and/or explosion on the other side of the connector, In particular. any flame and/or hot gas generated inside the enclosure 12 is prevented from causing a Fire rd/or explosion outside the enclosure 12. The passageways 38 may be configured in a number of ways in order to cool down any flame andior hot gas which progresses therethrough.

Typicay the passageways 38 are particularly narrow. In one example, the passageways 36 are substantiay longer then the longitudinal length of the connector 28 such that the length of the passageways 38 provides sufficient time for any progressing flame and/or hot gas to cool down during progression through the -5 passageways 38, wherein the passageways 38 are configured, for example, in a loop, spiral, serpentine pattern, labyrinth or the te. Altemabvely, and/or in addition to increasing the length of the p-assageways 38, the passageways 38 may comprise an increased surface area therethrough such that heat from any flame and/or hot gas can be more efficiently removed from said flame and/or hot gas by conduction of that heat by the Increased surface area the said flame and/or hot gas is exposed to.

The device 53 comprises an electric motor 56. The electric motor 56 is controlled by the power unif 14 -according to commands provided by the control unit 52. Typicay, the foUowing rotationS parameters associated with the electric motor 56 can be controfled by the power unit 14, including: angular positioning, angular speed, angular acceleration, timing, torque, or the like. y controWng these rotational parameters, the electric motor 56 can be used to provide a rotational drive movement t.,,-3-,4,-, -&s, ka, k n4r,sr3 *r nwd, ,Aker4 4t 2 Aj-s,q,s w' w w t, l.q c part of a feedback loop, wherein the &eotric motor 56 could be adjusted to respond to commands issued by the control unit 52 in response to said feedback.

The apparatus is typicafly configured to be operated at an ambient operational temperature of between 20t and +5OC, Further, the apparatus is l)'picaUy configured for use in Zone 1, gas group IIB, temperature class T4 environments (as defined in the ATEX guidelines). A person skilled in the act would appreciate that different temperature ranges and certification regimes could be accommodated and/or adhered to.

In reference to Figure 7, the electric motor 56 is configured to drive a reeling device 56 via rotational drive movement of rotor drive 60. The reeling device 58 is configured to reel an umbilicS 62 which is configured to prode operations for object 64. The reeng device may hpicay be positioned on a ptfonii 66 positioned above a sea level depicted by dashed Hoe 68, wherein the object is shown to be below the sea level 68, hut may also be above the sea level 68 and/Or on top the platform $6.

The abihty to use the electric motor 56 to drive the reellng device 58 provides significant advantages that are technically difficult to achieve otheSse. In pathcular, the rotafional drive parameters referred to above in reference to Figure 5 can he adapted for advantageous operation of the reellng device 58. in particular, the electric motor 56 can be used to control at least one of the following reellng parameters associated with the umbifical $2 of the reehog device 58, indudhig: positioning, timing, speed, acceleration, deceleration, tension, dutch control, gearing, or the hke, Further, feedback from the reeng device 58 can he used to form a reehng feedback loop to control parameters associated with umbillcal reeling operations. For example, the reeling feedback loop could be used to control positioning of the umbilical 62 in a given location and to subsequently accurately reposition the umbllical 62 in the given location, or at an accurately specified location relative to the given location. In another example, the reellng device 58 can he configured as part of a tension feedback loop to compensate for tension changes in the umbilical 62, for example, due to wave movement.

It should be understood that the embodiment depicted in Figures 1 to 7 principally outlines a synergistic effect between the apparatus, power unit, enclosure and electric motor, thus providing the interUnking features and advantages of the present embothment, wherein the electric motor is provided to drive the reeling device. However the reeling device is one example of a device requiring a specialised power supply. Instead, the reeling device could be replaced by any other device requiring rotational drive movement. A skilled person would understand that the present invention could be used in any situation requiring a specialised power supply in an explosive environment, for example, in providing a winching apparatus or a pump. 1$

Claims (25)

1. CLAiMS 1. A cooled flameproof power supply apparatus comprising: a flameproof enclosure; a power unit to provide a specialked power supply to a devke extern& to the enclosure, wherein the enclosure houses the power unit; a cooUng quid conduit adjacent the power unit and configured to remove heat therefrom; and a flameprooF connector configured to provide communication of coohng liqiüd through a wa of the enclosure, wherein the flameproof connector communcates with the cooUng Uquid conduit.
2. 2. The apparatus according to claim 1, wherein the connector defines a passageway configured to at least partially cod any flame or hot gas which progresses therethrough such that said any flame or hot gas is exfinguished or cooled by an amount sufficient to prevent ignition of any explosive matter situated adjacent the connector.
3. 3. The apparatus according to any preceding cm, wherein the enclosure comprises at east one harder gland to permit at least one ot input cabng and output cabhng to be run through a wa of the enclosure.
4. 4. The apparatus according to claim 3, wherein the input cabng is configured to communicate input power from a power source external from the enclosure to the power unit and the output cabhng is configured to communicate the speciabsed power supply from the power unit to the device.
5. 5. The apparatus according to any of claims 3 or 4, wherein the barrier gland is configured to prevent any flame or hot gas from progressing therethrough.
6. 6. The apparatus according to any of claims 3 to 5, wherein the at least one harrier gland permits contro' cabng to be run through a waH of the enclosure wherein the contra! cabUng is configured to control the power unit.
7. 7. The apparatus according to any preceding claim, wher&n the apparatus comprises a conduit circuit comprising an inner conduit circuit including the coofing liquid conduit inside the enclosure and an outer conduit circuit outside the enclosure,
8. 8. The apparatus according to any preceding claim, wherein the apparatus comprises a plurafity of connectors, at east one connector being configured as an inlet and at east one connector configured as an ouflet.
9. 9. The apparatus according to any preceding claim, wherein the apparatus comprises two or more connectors configured as inlets.
10. 10, The apparatus according to any preceding c!aim, wherein the apparatus comprises two or more connectors configured as outlets.
11. 11. The apparatus according to any preceding claim, wherein at least one junction is provided to connect two or more connectors to en inner or outer conduit circuit.
12. 12. The apparatus according to any preceding claim, wherein the enclosure comprises at least one further connector provided separatey from a coofing quid circuit.
13. 13. The apparalus according to claim 12, wherein the further connector is configured to operate as a breather to permit gas/air pressure equasation between inside and outside the enclosures.
14. 14. The apparatus according to any of Sims 11 b 13, wherein the further connector is configured to permit purging of Sr and/or gas from within the enclosure,
15. 15. The apparatus according to any of claims 1 1 to 14, wher&n the further connector permits drainage of liquid from the enclosure.
16. 16. The apparatus according to any preceding claim, wherein the enclosure is configured to maintain a positive pressure therein.
17. 17. The apparatus according to any preceding claim, wherein the apparatus comprises a heat sink.
18. 18. The apparatus according to claim 17, wherein the heat sink is in communication wllh the coohng liquid conduit and is configured to receive heat generated by the power unit.
19. 19. The apparatus according to any of claims 17 or 18, wherein the heat sink is configured to transfer heat to cooUng flquid being communicated within the conduit.
20. 20. The apparatus according to any preceding claim, wherein the apparatus comprises a heat dissipation apparatus positioned outside the enclosure.
21. 21. The apparatus according to any preceding claim, wherein the power unit produces electricS output power of more than 30 KW.
22. 22. The apparatus according to any preceding claim, wherein the specialised power supply provided by the power unit is configured to controably adjust at east one electrical parameter, wherein the at east one electrical parameter is one or more of current, voltage and frequency.
23. 23. The apparatus according to any of claim 22, wherein the. power unit includes a variable frequency drive, variable speed drive or inverter drive.
24. 24. The apparatus according to any of claims 22 to 23, wherein the power unit is configured to be conLroUed externaUy by a control unit situated external to the enclosure.
25. 25. The apparatus according to any preceding claim, wherein the device comprises a component which requires the spedaUsed power supply.28. The apparatus according to claim 25, wherein the component includes an electric motor.27. The apparatus according to any preceding claim, wherein the power unit is configured to control at least one rotational parameter associated with a rotational drive movement of an electric motor, including at least one of angular positioning, angular speed, angular acceleration, timing or torque.28. The apparatus acoording to any preceding claim, wherein the device is controlled as part of a feedback loop.29. The apparatus according to clam 28, wher&n an Sectric motor is configured to respond to feedback from the device.30. The apparatus according to any preceding claim, wherein the device a a reeng device.31. The apparatus according to claim 30, wherein the reeling device comprises an umbffica configured to be re&ed by the re.eng device.32, The apparatus according to claim 31, wherein an electric motor controls at least one reehng device parameter associated with the umbilicaL including at east one of positioning, timing, speed, acceleration, deceleration, umbiilcal tension, cutch control or gearing.33. The apparatus according to any of claims 31 or 32, wherein the reeling de*.e is configured in a reeflng feedback loop to control parameters associated with reeling ihe umbilical, 34. The apparatus according to daim 33, wherein the reeling device is configured as part of a tension Feedback loop to compensate for tension changes in the umbilical