RU2742670C1 - Method of using excess heat of a power oil transformer to heat nearby objects - Google Patents

Abstract

FIELD: heat power engineering.

SUBSTANCE: invention relates to heat generation and heat use with the help of heat pumps. The invention can be used for heating rooms and other objects located near a power transformer. The method consists in extracting heat from the power transformer and transferring it to the heating circuit of a room or other object. Excess heat from the transformer oil is taken by means of an intermediate heat carrier passing through a double-circuit spiral tubular heat exchanger installed in the power transformer tank. It is directed with the help of circulation pumps. If there is no need for heating an object, it is directed through a pipeline system through a multi-way valve to a horizontal ground heat exchanger which is placed in a heat accumulator made in the form of a heat-insulated volume of a mixture of granite crushed stone and river sand. Heat is removed from the intermediate heat carrier into the heat accumulator. After that the cooled heat carrier is again directed to the spiral tubular heat exchanger of the power transformer.

EFFECT: invention provides possibility of using a power transformer as a source of heat supply for heating rooms.

1 cl, 1 dwg

Description

The invention relates to the field of obtaining and using heat using heat pumps and is intended for heating rooms and other objects located near a power transformer.

The closest in technical essence is the RF patent No. 2234755, IPC H01F27 / 08, publ. 08/20/2004, which discloses a method for operating an installation for using excess heat from a power transformer for heating residential buildings or other structures, in which cooling oil circulates from the power transformer through a pipeline to an outside plate heat exchanger and back. In this heat exchanger, the heat from the transformer oil is transferred to the intermediate heat carrier flowing through the pipeline to the nearby heat pump and back. Heat from the heat pump is transferred using the heating medium of the heating system to heat-consuming modules, for example, the radiators of a building. Also in the system, after the plate heat exchanger, there is a pipeline that enters the rocky ground, earth or water, which can be used either as a heat radiator (ground heat) or as a heat sink (heat accumulator). The circulation of heat carriers is provided by circulation pumps, and the direction of flows is controlled by multi-way valves that change their position directly from the readings of the temperature sensors of the pipelines (RF patent No. 2234755, IPC H01F27 / 08, publ. 20.08.2004).

The disadvantages of the known method are its applicability only for closed transformer substations of high power, as well as the presence of heat losses in the system and insufficiently high efficiency of heat extraction from the power transformer.

The objective of the present invention is to provide heat supply to objects located near a transformer substation by taking heat from a power transformer and transferring it to the heating system of objects by using an indoor heat exchanger, an intermediate heat carrier, a pipeline system, a heat pump, storing the obtained heat using a heat accumulator, with control of the process of heat production, its transportation, storage and use at the heat supply facility using an automated system, as well as ensuring the possibility of increasing the service life of the transformer by forming a more uniform temperature distribution in the tank space and reducing the amplitude of its oscillations

As a result of using the proposed invention, it is possible to use a power transformer as a source of heat supply, transfer heat from it to a heat supply object using an indoor heat exchanger, an intermediate heat carrier, a pipeline system, a heat pump, with the possibility of accumulating heat energy in a heat accumulator, with control of the production process heat, its transportation, storage and use at the heat supply facility using an automated system, as well as ensuring the possibility of increasing the service life of the transformer by forming a more uniform temperature distribution in the tank space and reducing the amplitude of its oscillations.

The above technical result is achieved by the fact that in the proposed method of using excess heat of a power oil transformer for heating nearby objects, which consists in taking heat from a power transformer and transferring it to a heating circuit of a room or other object, according to the invention, it is taken with the help of an intermediate heat carrier passing through through a double-circuit spiral tubular heat exchanger installed in the tank of a power transformer, excess heat from the transformer oil and direct it using circulation pumps, if there is no need to heat the object, through a pipeline system through a multi-way valve to a horizontal ground heat exchanger, which is located in a heat accumulator, made in the form of a heat-insulated volume of a mixture of granite crushed stone and river sand, heat is taken from the intermediate heat carrier into the heat accumulator, after which the cooled heat carrier is again directed into the spiral tubular heat exchanger of the power transformer, and if it is necessary to heat the heat supply object, the heated coolant from the spiral tubular heat exchanger is directed through pipelines using multi-way valves to the heat pump, with which the potential of the received heat energy is increased and transferred to the heating circuit of the heat supply object, the cooled the intermediate heat carrier from the heat pump to the spiral tubular heat exchanger of the transformer, in case of the need to heat the object with the power transformer disconnected from the electrical network, the heat carrier heated from the heat accumulator is directed from the horizontal ground heat exchanger through multi-way valves to the heat pump, with the help of which the potential of the obtained heat energy is increased and transfer it to the heating circuit of the heat supply object, return the cooled coolant back to the heat accumulator, control all and devices of the system and the transition to different modes of operation with the help of the control complex automatically, depending on the parameters of the modes of operation of the heat supply object, power transformer, coolant and heat accumulator.

The essence of the invention is illustrated by a drawing, according to which CT is a power transformer; CTTO - double-circuit spiral tubular heat exchanger; Kstto1 - valve for switching circuits at the entrance to the CTTO; Kstto2 - valve for switching circuits at the outlet of the CTTO; TbPr1 - pipeline from CTTO to MHK1; TsN1 - circulation pump for TbPr1; МХК1 - multi-way valve of the outlet circuit; TbPr2 - pipeline from MHK1 to HP; ТН - water-to-water heat pump; P - room; KO - heating circuit; TsN2 - circulation pump in KO; TbPr3 - pipeline from ТН to МХК2; МХК2 - multi-way valve of the supply circuit; TbPr4 - pipeline from MHK2 to CTTO; TsN3 - circulation pump for TbPr4; TbPr5 - pipeline from MHK1 to GGTO; ГГТО - horizontal ground heat exchanger; TsN4 - circulation pump for TbPr5; AkT - heat accumulator; TbPr6 - pipeline from GGTO to MHK2; TsN5 - circulation pump for TbPr6; UK - control complex (microcontroller); ДТ1 - transformer oil temperature sensor; DT2 - indoor air temperature sensor; ДД1 - pressure sensor in the transformer zone; ДД2 - pressure sensor in the heat storage area; ДД3 - pressure sensor in the heat pump zone; ДД4 - pressure sensor in KO; K - channel for placement of pipelines and circulation pumps.

The method is implemented as follows.

A CTTO double-circuit heat exchanger is placed in the tank of the CT power oil transformer, preferably made of a material with low thermal conductivity. One CTTO circuit is the main one, and the second is the backup. The required CTTO circuits are activated by the Kstto1 and Kstto2 valves. Heat from transformer oil is removed only through the CTTO. The temperature of the transformer oil is monitored using the DT1 sensor. Heat exchanger CTTO is connected to pipelines TbPr1 and TbPr4, at opposite ends of which multi-way valves MHK1 and MHK2 are installed. These valves are “regulators” and control the direction of the coolant flows in the system, dividing it into three conditional zones: transformer, heat storage and heat pump. This paragraph deals with the transformer zone. The circulation of the coolant in this zone is provided by pumps TsN1 and TsN3, and the pressure is controlled by the sensor ДД1.

In the heat storage zone, pipelines TbPr5 and TbPr6 are connected to MHK1 and MHK2, at opposite ends connected to the GHPO heat exchanger. GHPO is placed in the AkT heat accumulator in two layers: the first at a depth of 0.5 m from the surface, and the second - 0.5 m below the first. AkT is a thermally insulated volume of a mixture of crushed granite and river sand in a ratio of 2.6 / 1. The circulation of the coolant in this zone is provided by the TsN4 and TsN5 pumps, and the pressure is controlled by the DD2 sensor.

In the heat pump zone, pipelines TbPr2 and TbPr3 are connected to MHK1 and MHK2, connected at the other end to the heat pump TH. The pressure in them is controlled by the DD3 sensor. In turn, the heat pump is connected to the heating circuit of the KO room or another heat consumer. The circulation of the coolant in the boiler is carried out by TsN2, and the pressure in the boiler is monitored by the sensor DD4. In the entire system, except for heat pump (it uses freon), a mixture of water and alcohol is used as a heat carrier.

The general control and management of the system is carried out by the MC complex based on a microcontroller. In addition to the listed sensors, a DT2 sensor is additionally installed in the room to control the operation of the elements. Based on the data from all sensors, the microcontroller gives commands to the controlled elements according to a given program.

The proposed system for using excess heat from power transformers has three operating modes: cooling, heating and cooling, and heating.

The cooling mode serves mainly to cool the elements of the power transformer, and in addition contributes to the accumulation of heat in the ACT. This mode corresponds to the period when the air temperature in the room is above + 18 ° C, which is controlled by the DT2 sensor. In this case, the microcontroller uses only the transformer and heat storage zones of the system. The excess heat released by the active elements of the CT is removed through the transformer oil to the CTTO, in which a cold liquid heat carrier flows. Driven by STTO pumps TsN1 and TsN3, this liquid is heated to a temperature of about + 30 ° C, cooling the transformer. From CTTO, the heated coolant tends along TbPr1 to MHK1, which directs it through the TbPr5 pipeline to the GHP. In the heat exchanger of the GHPO, the reverse heat exchange of the heated coolant with the cold ACT takes place. Further, the coolant, again cooled to a temperature of about + 15 ° C, driven by TsN4 and TsN5, flows to the MHK2 valve and is sent through TbPr4 again to the CTTO. The pumps ЦН2 and ТН in the cooling mode remain off.

When the room temperature drops below + 18 ° C, the UK switches the system to the cooling and heating mode of operation. In this case, the microcontroller first turns off TsN4 and TsN5, then changes the position of MHK1 and MHK2, excluding their circuit of the heat storage zone and activating the heat pump. After that, the UK sequentially includes TN and TsN2. As a result, the coolant from the CTTO through TbPr1 through MHK1 and the TbPr2 pipeline enters the heat pump HP. In it, the heat from the heated coolant is transferred to freon (coolant in the HP), which, passing through the compressor in the HP, increases its thermal energy and transfers it to the KO. When the room temperature rises above + 24 ° С, the microcontroller reverses the order and switches the system back to cooling mode.

In the case when there is a planned or emergency disconnection of the power transformer from the mains, there are two options for the system. If at the moment the transformer was turned off, the system was in cooling mode, then the CC switches the system to standby mode, turning off the pumps TsN1, TsN3, TsN4 and TsN5 and leaving the state of the other devices unchanged. If, in the future, the air temperature in the room drops below + 18 ° C, then the UK will start the heating mode of operation. At the same time, the microcontroller will first move the MHK1 and MHK2 valves to a position that excludes the transformer zone from the circuit and turns on the heat storage zone, and then switches on in series TsN4, TsN5, TN and TsN2.

If, at the time of the transformer disconnection, the system was in heating and cooling mode, then the CC immediately switches the system to heating mode, acting in the following order. First, the microcontroller turns off the pumps TsN1 and TsN3, then changes the position of MHK1 and MHK2, excluding their transformer zone and activating the heat storage zone. Then it turns on the TsN4 and TsN5. When, in heating mode, the air temperature in the room rises above + 24 ° C, the UK sequentially turns off TsN2, TN, TsN5 and TsN4, leaving the rest of the devices unchanged.

When the power transformer is switched on to the network, the UK transfers the system to a cooling or heating-cooling mode (depending on the readings of the DT2 sensor) only after heating the transformer oil to a temperature above + 65 ° C, which is controlled by the DT1 sensor. The switching of the system elements when the power transformer is turned on occurs in the reverse order than when it is turned off. Also, the UK program provides for the regulation of the speed of the pumps TsN1, TsN3, TsN4 and TsN5, depending on the temperature of the transformer oil: it should be within + 60-70 ° C. That is, if DT1 shows a temperature below + 60 ° C, then the revolutions decrease, and if it is above + 70 ° C, then the revolutions increase. If, after increasing the speed of the pumps to the limit value, the oil temperature continues to rise (possibly with a strong overload of the power transformer), then the microcontroller sends a signal about this to the control room post and, using the Kstto1 and Kstto2 valves, connects the backup circuit of the spiral tubular heat exchanger to work until then until the oil temperature drops below + 60 ° C.

If suddenly one of the pressure sensors reports an unacceptable drop or increase in pressure in the system, then a signal is sent to the control post and the corresponding zone of the system is taken out of operation. So if the sensor DD1 is triggered, then the system is transferred to the heating mode of operation or standby mode, while the power transformer is turned off. If sensor DD2 is triggered, then the system is transferred to heating and cooling mode of operation or standby mode. If sensor ДД3 and (or) ДД4 is triggered, then the system is put into cooling or standby mode. If, after changing the mode, the second pressure sensor is also triggered (except for the case when DD3 and DD4 are triggered), then the entire system is switched to standby mode, the MHK1 and MHK2 valves shut off all pipelines, and the power transformer is turned off until normal pressure in the system is restored.

The use of the proposed method allows the use of a power transformer as a source of heat supply for objects located near it, to ensure an increase in the service life of the transformer due to the formation of a more uniform temperature distribution in the tank space and a decrease in the amplitude of its oscillations.

Claims (1)

A method of using excess heat from a power oil transformer for heating nearby objects, which consists in taking heat from a power transformer and transferring it to the heating circuit of a room or other object, characterized in that excess heat is taken from the transformer oil using an intermediate heat carrier passing through a double-circuit spiral a tubular heat exchanger installed in the tank of a power transformer and directed by means of circulation pumps, if there is no need for heating the object, through the pipeline system through a multi-way valve to a horizontal ground heat exchanger, which is located in a heat accumulator made in the form of a heat-insulated volume of a mixture of granite crushed stone and river sand, they take heat from the intermediate heat carrier into the heat accumulator, after which the cooled heat carrier is again sent to the spiral tubular heat exchanger of the power transformer, and in the case the need to heat the heat supply object, the heated coolant from the spiral tubular heat exchanger is directed through pipelines using multi-way valves to the heat pump, with the help of which the potential of the obtained heat energy is increased and transferred to the heating circuit of the heat supply object, the cooled intermediate heat carrier is returned from the heat pump to the spiral tubular heat exchanger of the transformer , if the need arises to heat the object when the power transformer is disconnected from the electrical network, the heat carrier heated from the heat accumulator is directed from the horizontal ground heat exchanger through the multi-way valves to the heat pump, with the help of which the potential of the obtained heat energy is increased and transferred to the heating circuit of the heat supply object, cooled the coolant again to the heat accumulator, they control all the devices of the system and switch to different modes of operation using the control the power complex automatically depending on the parameters of the operating modes of the heat supply object, power transformer, coolant and heat accumulator.

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