Transformer Oil Regeneration Plant CMM-6R
Technical specifications
| Parameter | Units | Value |
| Capacity | m3/hour | 1 |
| Maximum allowable oil temperature | оС | 90 |
| Outlet pressure | bar | 1,5 |
| Oil heater power | kW | 50 |
| Vacuum system nominal suction rate | m3/hour | 280 |
| Fuller’s earth load | kg | 900 |
| Maximum power consumption | kW | 95 |
| Electric parameters | ||
| Phases | 3p+1N+PE | |
| Voltage | V | 415 |
| Frequency of AC | Hz | 50 |
| Connections | ||
| Oil inlet | DN | 25/Camlock C100 |
| Oil outlet | DN | 25/Camlock C100 |
| Transformer evacuation inlet | DN | Flange DN100 |
| Vacuum pump exhaust | DN | 32/G1 1/4 |
| Reactivation exhaust | DN | 50/G 2” |
| Filter element specifications | ||
| Strainer (mesh filter) | hm | 100 |
| Pre-filter with filter element | hm | 25 |
| Regeneration section filter with filter element | hm | 0,2х2 |
| Fine filter with filter element | hm | 5 |
| Dimensions (without trailer) | ||
| Length | mm | 10680 |
| Width | mm | 2090 |
| Height | mm | 2110 |
| Weight | kg | 8000 |
Parameters of processed oil
| Parameter | Unit | Value |
| In 1 thermal vacuum degassing cycle | ||
| Moisture content | ppm | 5 |
| Volumetric gas content | Vol % | 0,1 |
| In 3 thermal vacuum degassing cycles | ||
| Moisture content | ppm | 3 |
| Volumetric gas content | Vol % | 0,05 |
Parameters of used oil after regeneration
| Parameter | Unit | Value |
| In 1 thermal vacuum degassing cycle | ||
| Moisture content | ppm | 5 |
| Volumetric gas content | Vol % | 0,1 |
| Acid number, as per IEC 296; ASTM D-664 | mg КОН/g | 0,01 |
| Corrosive sulfur as per ISO 5662; ASTM D-1275 | None | |
| Breakthrough voltage, as per IEC 156; ASTM D-1816 | kV | 70 |
| Interfacial tension, at 25oС as per ISO 6295; ASTM D-2285 | N/m | 45 |
| Dissipation factor at 90oС as per IEC 247; ASTM D-924 | 0,001 | |
UNIT DESCRIPTION
Composition of the unit:
- The unit is a frame with the following components:
- Oil degassing section (also referred to as degasser in this manual)
- Oil regeneration section
- Operator room
- The unit is used during installation, maintenance and operation of oil-filled high voltage equipment (power transformers, high-voltage switchgear, etc.).
- The unit is designed for processing of electric insulation oils and servicing of transformers.
The process of dielectric oil treatment includes the following:
- Removal of dissolved gases.
- Removal of free and dissolved water.
- Removal of particulate matter.
- Removal of oil degradation products.
Servicing of transformer includes:
- Evacuation of the transformer.
- Heating of the transformer and its core with hot oil.
- Removal of sediment from the coils of the transformer.
Operation process
- The principle of processing the dielectric oil is heating the oil and passing it through a vacuum vessel. The heat and low pressure reduce partial pressure of water and gases in the oil. This facilitates evaporation of water and emission of gases and their removal.
- Degradation products are removed by sorbent (Fuller’s earth. The oil is directed to vessels, containing the sorbent. When the oil contacts the sorbent, the oil is filtered on molecular level. The oil’s chemical and physical properties are thus restored.
- Sorbent is reactivated in the Sorbent reactivation mode. This method allows reusing the sorbent without the need to replace it.
Methods of operation
The oil may be treated as follows:
- Connection of the unit’s inlet and outlet to an oil vessel and circulating the oil in the vessel.
- Connection of the unit’s inlet and outlet to a transformer and circulating the oil in the transformer.
- Connection of the unit’s inlet to an oil vessel, and connection of the outlet to a transformer.
- Connection of the unit’s inlet to one oil vessel and the unit’s outlet to another oil vessel.
- For evacuation of transformer or other equipment, the unit is equipped with a vacuum evacuation port.
UNIT DESIGN
The unit consists of two primary operating sections: the degasser and the regeneration section. These sections are interconnected by pipelines.
The unit is optionally equipped with a system to control oil level in the transformer, the TSS (Transformer Security System).
The unit is controlled by an industrial PLC controller, which is programmed for operation and control of the unit’s components.
Location of the unit’s main components
Electric control system
- Automation and electric control system consists of two power cabinets and a control cabinet.
- Power cabinet is installed directly on the unit’s frame. The cabinet contains communication equipment: magnetic starters, motor protection automation, heating power control section and automatic switches (circuit breakers), while the control cabinet contains the controller with a number of digital and analogue inputs and outputs.
- Automatic protection of motor drives (Q1 – Q6) are installed for protection of the motor from current overloads and short circuits. The magnetic starters (КМ2 – КМ7) move the drives in accordance with the logic programmed in the controller.
- The power of electric heater is controlled by a solid state relay and depends on the current throughput and temperature set by the operator. The heaters are protected from short circuit by a triplepole switch.
- The control cabinet is located in the operator room and contains power supply, reducing transformers, power supply filter and automatic protection. The front panel contains power supply and phase control lights, emergency stop button and the control touch panel.
The control panel in the operator room
Components of the control system
| Pos | Item | Description |
| 1. | Touch panel | The panel is used to control the unit’s components |
| 2. | Manual circuit breaker lever | Disconnects power supply |
| 3. | “Phase control” light | The light is on if power is connected correctly |
| 4. | “Power” light | The light is on when the unit is powered |
| 5. | “Stop” button | Emergency stop button |
Using the operator touch panel
- The control system is based on a controller and a touch panel. The controller contains a set of instructions to control the logic of actuator operation.
- The touch panel is a device for display and control. The panel allows the operator to view main parameters, such as the temperature, pressure, vacuum and throughput, as well as the status of actuators. The panel is also a means to control the processes in the controller’s memory.
- The control system is designed for the following modes of operation:
| Mode | Specifics | |
| «СHARGING» mode – filling the unit. | In this mode, the vessels of the unit are filled to the maximum level, and air is released from pipelines. | |
|
Oil regeneration/degassing mode: «DEGASING/REGENERATION»
|
Oil degassing | Moisture, gases and solids are removed from transformer oil in this mode. |
| Oil regeneration | Oil is regenerated and degassed in this mode. | |
| Sorbent reactivation |
Sorbent properties are restored in this mode. All contaminants within the sorbent are burned out, those that cannot be burned out are collected in waste trap. While this mode is active, the unit continues to degas the oil in the transformer. |
|
| Equipment testing and adjustment mode: «MANUAL». | All components of the unit may be turned on or off in this mode. | |
- Mode of operation is selected from the start screen
- – Start screen; 2. – Charge mode selection button; 3. – Degassing mode selection button; 4 – Transformer Safety System selection button; 5 – Manual mode selection button
Degassing section flow diagram
Degassing section components
| Pos | Item | Description |
| MV 1 ; MV 1.1 | Ball valves | Stops oil flow into the unit |
| V1 | Automatic oil inlet valve | Stops oil flow into the unit. |
| P1 | Centrifugal pump | Pumps oil into the unit. |
| MF1 | Coarse filter | Stops particles larger than 100 micron |
| LS1 | Oil level sensor | Stops the unit when no oil is present at inlet |
| MV2 | Ball valve | Drains oil from coarse filter |
| FCV | Regulation valve | Adjusts the flow rate of oil input |
| G1 | Pressure sensor | Indicates pressure at coarse filter inlet |
| SV1 | Ball valve | Sampling valve for incoming oil |
| F1 | Fine filter | Stops particles larger than 25 micron |
| AV1 | Air release valve | Discharges air from filter |
| MV3 | Ball valve | Drains oil from fine filter |
| G2 | Pressure sensor | Indicates pressure at coarse filter outlet |
| Н | Oil heater | Heats the oil to operating temperature |
| MV4 | Ball valve | Drains oil from the heater |
| T1 | Thermistor | Controls oil heating |
| T2 | Thermostat | Prevents oil overheating |
| FS1 | Flow switch | Controls oil heating and prevent oil heater from engagement with no oil flow |
| LC1 | Flow counter | Used for flow control and counting of total treated oil |
| VC | Vacuum column | Boiling and emission of water and gases from the oil |
| V3 | Automatic ball valve | Supplies the oil to regeneration section |
| V2 | Automatic ball valve | Stop oil line to the column |
| V4 | Automatic ball valve | Sends oil to the unit after regeneration |
| V5 | Angle valve | Prevents oil from being sucked into the column by vacuum |
| VC | Vacuum column | Water and gases boil out of the oil in the column |
| MV5 | Disk gate | Vacuum system stop valve |
| OT | Oil trap | Foam or oil mist trap |
| MV6 | Disk gate | Vacuum to transformer valve |
| MV7 | Ball valve | Vacuum system stop valve |
| MV8 | Ball valve | Drain oil from oil trap |
| V7 | Electromagnetic valve | Air inlet into vacuum system in emergencies and to reduce foaming |
| VG1 | Vacuum sensor | Indicates vacuum pressure, locks booster pump operation if vacuum not sufficient |
| LS4 | Oil level sensor | Shows oil level in trap. Stop the unit if the level of oil in the trap exceeds acceptable level. |
| VP1 | Backing pump | Creates vacuum to 30 mbar |
| VP2 | Roots pump | Creates vacuum to 1 mbar |
| FL | Foaming sensor | When foam appears in the vacuum column, this sensor commands air inlet valve open |
| SL2 | Liquid level sensor | Stops oil input pump if the oil level exceeds limit |
| SL3 | Liquid level sensor | Stop oil output pump if the oil level falls below limit |
| MV9 | Ball valve | Drains oil from vacuum column |
| P2 | Centrifugal pump | Drains oil from the vacuum column and supplies it to the unit’s outlet |
| MV10 | Ball valve | Vacuum column oil level control system adjustment valve |
| MV11 | Ball valve | Vacuum column oil level control system adjustment valve |
| MF2 | Mesh filter | Protects oil level control system from contamination. |
| G4 | Pressure and vacuum sensor | Indicates pressure in oil level control system |
| V8 | Angle valve | Prevents oil from being sucked into the vacuum column by vacuum. Controls oil level in the vacuum column |
| V9 | Automatic ball valve | Bypass line valve. Lets the oil bypass the vacuum column in heating and filtration mode |
| G5 | Pressure sensor | Indicates pressure at coarse filter inlet |
| F2 | Fine filter | Stops particles larger than 25 micron |
| AV2 | Air release valve | Removes air from filter |
| MV12 | Ball valve | Drains oil from fine filter |
| G6 | Pressure sensor | Indicates pressure at coarse filter outlet |
| SV2 | Ball valve | Incoming oil sampling valve |
| V10 | Automatic ball valve | Stops oil output from the unit. |
| V11 | Automatic ball valve | Oil circulation valve |
| MV 13 ; MV 13.1 | Ball valves | Stop oil input to the unit. |
| LP1 | Leak collector | Leak collector/tray to contain spills in emergency situations |
| LS5 | Oil level sensor | Stop the unit if an oil spill is detected |
| BV1 | Return valve | Prevents air from being sucked into the F1 filter by vacuum |
| BV2 | Return valve | Prevents air from being sucked into the F2 filter by vacuum |
| MV14 | Ball valve | Tray oil drain valve |
| MV15 | Ball valve | Buffer tank filling line stopping valve |
| V12 | Electromagnetic automatic valve | Send oil to buffer tank |
Regeneration section flow diagram
Regeneration section components
| Position | Item | Description |
| V13 | Automatic ball valve | Stops oil flow in sorbent reactivation mode |
| AV3 | Air release valve | Removes air from pipeline |
| G7 | Pressure sensor | Adjust vacuum system capacity during sorbent reactivation |
| V14 | Automatic ball valve | Opens air flow to the column during reactivation |
| AF | Air filter | Purifies air entering the columns during reactivation |
| С1-С6 | Sorbent column | Transformer oil regeneration column |
| ТС1-ТС15 | Thermistor | Indicates temperatures during sorbent reactivation |
| DP | Intermediary tank | In this vessel air bubbles are separated during oil regeneration, and condensate formed during reactivation is collected and discharged |
| MV15 | Ball valve | Oil drain from drain tank |
| LS6 | Level sensor | Indicates oil presence in the bottom of intermediate tank. |
| LS7 | Level sensor | Indicates oil presence at the top of the intermediate tank |
| G8 | Pressure sensor | Indicates pressure in the intermediate tank |
| F3 | Intermediary filter | Stops particulate matter after oil regeneration |
| AV4 | Air discharge vavle | Removes air from fine filter |
| MV26 | Ball valve | Drains oil from spill tray |
| G10 | Pressure sensor | Indicates filter contamination |
| V15 | Automatic ball valve | Stops vacuum line during oil regeneration |
| MT | Condenser | Condenses moisture and heavy fractions during sorbent reactivation |
| MV16 | Ball valve | Drains condensate from the condenser |
| LS8 | Level sensor | Indicates level limit in the condenser |
| V16 | Automatic ball valve | Stops vacuum line during oil regeneration |
| G9 | Pressure sensor | Adjust vacuum system operation during sorbent reactivation |
| MV17 | Ball valve | Lets air into the vacuum system |
| VP3 | Vacuum pump | Creates air flow required for sorbent reactivation |
| SR | Noise suppressor | Reduces noise at the outlet of the vacuum system |
| MV18 | Ball valve | Drains moisture from the noise suppressor SR |
| MV19 | Ball valve | Vacuum system exhaust valve. Used for direct exhaust bypassing charcoal filter CF. |
| MV21 | Ball valve | Disconnects charcoal filter CF from exhaust line |
| MV22 | Ball valve | Drains condensate from charcoal filter СF |
| CF | Charcoal filter | Purifies exhaust during sorbent reactivation |
| P3 | Screw pump | Pumps condensate from the exhaust line |
| SF1 | Safety valve | Prevents the body of pump P3 from overpressure |
| BV3 | Return valve | Prevents oil from being sucked into the intermediary tank DP |
| V17 | Automatic ball valve | Pumps reactivation waste and corrosive sulfur into buffer tank BT |
| BT | Buffer tank | Oil tank. Used for adding oil to the unit and collection of condensate. |
| LS9 | Level sensor | Limits oil level in the buffer tank. |
| V18 | Automatic ball valve | Pumps oil into buffer tank BT |
| V19 | Automatic ball valve | Supplies oil from the buffer tank BT |
| MV23 | Ball valve | Drains condensate from settling tank |
| MV24 | Ball valve | Drain from buffer tank |
| MV25 | Ball valve | Drain from buffer tank |
| P4 | Centrifugal pump | Lets oil out of buffer tank BT and refills the unit with oil |
| FS2 | Flow relay | Registers oil flow during refilling of the unit with oil. |
| LP2 | Spill collector | Tray to collect oil spills in emergencies |
| LS10 | Oil level sensor | Stop the unit of an oil spill is detected |
| BV4 | Return valve | Stops air from being sucked into the line by vacuum |
| BV5 | Return valve | Stops air from being sucked into filter F3 by vacuum |
| MV27 | Ball valve | Spill tray drain valve |
Flow diagram of transformer oil level control system TSS (Transformer Security System)
Oil level control system components
| Position | Item | Description |
| V21 | Electromagnetic valve | The valve prevents oil spills from the transformer in emergencies |
| MV27 | Ball valve | Redirects oil flow during operation |
| MV28 | Ball valve | Redirects oil flow during operation |
| MV29 | Ball valve | Redirects oil flow during operation |
| MV30 | Ball valve | Redirects oil flow during operation |
| MV31 | Ball valve | Redirects oil flow during operation |
| V22 | Electromagnetic valve | The valve prevents oil spills from the transformer in emergencies |
| V4 | Air discharge valve | Removes air from pipelines |