An ohmic electric heater for high voltage applications

Abstract

The utility model relates to the technical field of electric heaters, and in particular to an ohmic electric heater for high voltage applications. It comprises: a circulation tube, which adopts a spiral tube structure, and is provided with a plurality of electrodes and distributed circumferentially; a plurality of electrodes 1, and each of the circulation tubes is provided with one of the electrodes 1, so that the plurality of electrodes 1 are distributed circumferentially; an inlet / outlet flange, which is respectively connected to the inlet / outlet ends of the plurality of circulation tubes. The circulation tube adopts a spiral steel tube, and the interior of the spiral steel tube and the inner wall of the inlet / outlet flange also include a high temperature resistant and high voltage resistant insulating coating. The utility model uses the ohmic resistor generated by the conductive fluid medium, and relies on the self-heating of the ohmic resistor to achieve the outlet temperature requirement. In addition, due to the self-heating of the medium, it has higher thermal efficiency than traditional electric heaters.

Description

Technical Field

[0001] The utility model relates to the technical field of electric heaters, in particular to an ohmic electric heater used in high voltage occasions. Background Art

[0002] Traditional circulating electric heaters generally use electric heating tubes for heating. Magnesium oxide powder is used as the insulation material inside the electric heating tube. As the temperature rises, the dielectric strength and insulation performance of magnesium oxide powder decrease rapidly. If high voltage is applied at high temperature, the electric heating tube is easy to break down or burn. This is the bottleneck of traditional electric heaters in high-temperature applications under high voltage. Secondly, if an insulation material superior to magnesium oxide powder is used, the manufacturing cost is high, which is also a major reason why it is difficult to promote. Utility Model Content

[0003] The purpose of the utility model is to provide an ohmic electric heater for high voltage occasions, which meets the outlet temperature requirement by relying on the self-heating of the ohmic resistor generated by the conductive fluid medium. In addition, due to the self-heating of the medium, it has higher thermal efficiency than traditional electric heaters.

[0004] In order to solve the above technical problems, the utility model provides an ohmic electric heater for high voltage applications, comprising:

[0005] The circulation pipe adopts a spiral pipe structure, and is arranged in a plurality and distributed in a circumferential direction;

[0006] Electrode 1, a plurality of electrodes are arranged, and each of the flow tubes is correspondingly provided with one of the electrodes 1, so that the plurality of electrodes 1 are distributed circumferentially;

[0007] The inlet / outlet flanges are respectively connected to the inlet / outlet ends of the plurality of flow pipes. A similar electrode 2 is also provided near the inlet / outlet flange ends.

[0008] Preferably, the circulation pipe is a spiral steel pipe, and the inner surfaces of the spiral steel pipe and the inlet / outlet flange also include a high-temperature resistant and high-voltage resistant insulating coating.

[0009] Preferably, the insulating coating is made of an inorganic insulating material with high dielectric strength and high insulation performance.

[0010] Preferably, the thermal expansion coefficient of the insulating coating is close to the thermal expansion coefficient of the spiral steel pipe.

[0011] Preferably, the number of the circulation tubes arranged is three, and the number of the electrodes 1 arranged correspondingly is three; the three electrodes 1 are connected to power supply lines A, B and C respectively.

[0012] Preferably, the inlet / outlet end of the flow pipe near the inlet / outlet flange also includes an electrode 2 connected to the power supply N line, the structure of the electrode 2 is the same as that of the electrode 1, and the inlet / outlet flanges are grounded respectively.

[0013] Preferably, the electrode 1 includes: a circular electrode plate, a column terminal, a ceramic insulating sleeve and a guide hole; the top of the circular electrode plate is provided with the column terminal, the column terminal also includes the ceramic insulating sleeve sleeve, and the circular electrode plate also includes a plurality of evenly opened guide holes arranged in a circular array.

[0014] Preferably, each of the circulation pipes further comprises an integrally formed and welded mounting metal pipe, and the mounting metal pipe is used for inserting and mounting the ceramic insulating sleeve.

[0015] Preferably, it also includes a thickened pipe section arranged at the bottom of the installation metal pipe, both ends of the thickened pipe section are connected to the flow pipe by means of diameter changes, and the circular electrode plate is installed and accommodated by the thickened pipe section.

[0016] Preferably, it also includes a power junction box and a temperature sensor; the wiring terminal of the power junction box is connected to the column terminal of the electrode one; the temperature sensor is arranged outside the flow tube; the fluid flowing into the flow tube is a conductive medium, and the length and flow cross-sectional area of ​​the flow tube are adjustable.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] 1. The ohmic electric heater designed by the utility model is different from the traditional electric heating tube. It is based on the characteristics of the conductive fluid medium. When flowing through the circulation tube, the conductive medium has a certain shape. For example, when the conductive fluid medium flows through the spiral circulation tube, the conductive fluid medium has a spiral heat-conducting medium shape that matches the inner diameter of the spiral circulation tube. The reason for choosing the spiral structure is that its unfolded length is relatively long. If a small-diameter steel pipe is used, the cross-section of the conductive fluid medium is relatively small. In addition, the resistivity of the conductive fluid medium is significantly higher than that of the metal material. With a larger length and a smaller cross-section, a relatively large resistance can be generated, and it is easy to apply a high-voltage power supply. The outlet temperature requirement is achieved by the self-heating of the conductive fluid medium. In addition, due to the self-heating of the medium, it has a higher thermal efficiency than the traditional electric heater.

[0019] 2. The ohmic electric heater designed by the utility model fills the application gap in high-temperature and high-voltage heating occasions, and is particularly suitable for molten salt heating applications.

[0020] 3. The ohmic electric heater designed by the utility model uses very limited materials, and the cost of the equipment can be controlled very low. Especially at the current time of mass innovation in the field of heat storage, the launch of this equipment has a positive guiding significance for the promotion of the industry.

[0021] 4. The ohmic electric heater designed by the utility model has a design power of up to tens of megawatts due to the high voltage used. Compared with the traditional low voltage, the use of high voltage reduces a lot of power distribution, cable and construction costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The utility model is a three-dimensional diagram of an ohmic electric heater used in high voltage occasions.

[0023] Figure 2 The utility model is a top view of an ohmic electric heater used in high voltage applications.

[0024] Figure 3 This is a stereoscopic diagram of the installation of the electrode, the mounting metal pipe and the thickened pipe section in the utility model.

[0025] Figure 4 It is a three-dimensional diagram of the electrode in the utility model.

[0026] In the figure: 1-flow pipe, 2-electrode 1, 21-circular plate, 22-column terminal, 23-ceramic insulating sleeve, 24-flow guide hole, 3-inlet / outlet flange, 4-mounting metal pipe, 5-thickened pipe section. DETAILED DESCRIPTION

[0027] The utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the utility model will become clearer. It should be noted that the drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model.

[0028] Embodiment 1:

[0029] like Figures 1 to 4 As shown, the embodiment of the utility model provides an ohmic electric heater for high voltage applications, comprising:

[0030] The circulation pipe 1 adopts a spiral pipe structure, and is arranged in a plurality of circumferentially distributed manner;

[0031] There are several electrodes 2, and each flow tube 1 is provided with one electrode 2, so that the electrodes 2 are distributed in the circumferential direction;

[0032] The inlet / outlet flanges 3 are respectively connected to the inlet / outlet ends of a plurality of flow pipes 1. There is also a similar electrode 2 near the inlet / outlet flange ends.

[0033] The circulation pipe 1 is a spiral steel pipe, and the inner surfaces of the spiral steel pipe and the inlet / outlet flange 3 also include a high temperature resistant and high voltage resistant insulating coating.

[0034] The insulating coating is made of an inorganic insulating material with high dielectric strength and high insulation performance, preferably an inorganic material or inorganic glue.

[0035] The thermal expansion coefficient of the insulating coating is close to that of the spiral steel pipe to prevent the insulating coating from cracking or falling off due to the difference in thermal expansion coefficients during heating.

[0036] There are three flow tubes 1 arranged, and there are three electrodes 2 arranged accordingly; the three electrodes 1 (2) are respectively connected to the power supply A line, B line and C line (A line, B line and C line are all live wires).

[0037] The inlet / outlet end of the flow pipe 1 near the inlet / outlet flange 3 also includes an electrode 2 connected to the power supply N line (N line is the neutral line). The structure of the electrode 2 is the same as that of the electrode 1, and the inlet / outlet flanges 3 are grounded respectively.

[0038] Electrode 1 2 includes: a circular plate 21, a column terminal 22, a ceramic insulating sleeve 23 and a guide hole 24; a column terminal 22 is provided on the top of the circular plate 21, and the column terminal 22 also includes a ceramic insulating sleeve 23, and the circular plate 21 also includes a plurality of guide holes 24 evenly arranged in a circular array to facilitate the flow of fluid.

[0039] Each circulation pipe 1 also includes an integrally formed and welded mounting metal pipe 4 , and the mounting metal pipe 4 is used for inserting and mounting the ceramic insulating sleeve 23 .

[0040] The fluid flowing into the circulation tube 1 is a conductive medium, and the length and flow cross-sectional area of ​​the circulation tube 1 are adjustable. That is, when the fluid flowing through the spiral steel pipe is a conductive medium, the conductive fluid has an ohmic resistance according to the internal shape of the spiral steel pipe. When a high voltage is applied to the three electrodes 1-2, this ohmic resistance generates heat by itself to generate energy to meet the outlet temperature requirements. The required heating power under a certain high voltage is met by adjusting the length of the spiral steel pipe and the flow cross-sectional area of ​​the spiral steel pipe. Unlike other resistance heating, the use of metal materials leads to the problem of too high conductivity and difficulty in implementing high voltage heating.

[0041] Embodiment 2:

[0042] like Figures 1 to 4 As shown, based on the above-mentioned embodiment 1, the post terminal 22, the ceramic insulating sleeve 23 and the mounting metal tube 4 in the electrode 1 2 are sintered into one body by a ceramic-metal high-temperature sintering process, and are suitable for use in high-voltage occasions.

[0043] To facilitate the installation of the three electrodes 1 2 or 2, the pipe at the installation position of the electrode 1 2 or the electrode 2 can be thickened and then connected to the spiral pipe by reducing the diameter, that is, it also includes a thickened pipe section 5 arranged at the bottom of the installation metal pipe 4, and the two ends of the thickened pipe section 5 are connected to the flow pipe 1 by reducing the diameter, and the circular electrode plate 21 is installed and accommodated through the thickened pipe section 5.

[0044] Embodiment 3:

[0045] like Figures 1 to 4 As shown, based on the above-mentioned embodiment 2, it also includes a power junction box and a temperature sensor; the wiring terminal of the power junction box is connected to the column terminal 22 of the electrode 1 2; the temperature sensor is arranged outside the flow tube 1 to prevent the spiral tube wall temperature from overheating.

[0046] The above description is only a description of the preferred embodiment of the utility model, and is not any limitation on the scope of the utility model. Any changes and modifications made by ordinary technicians in the field of the utility model based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. An ohmic electric heater for high voltage applications, characterized in that: include: The circulation pipe (1) adopts a spiral pipe structure, and is provided with a plurality of spiral pipes distributed in a circumferential direction; A plurality of electrodes (2) are arranged, and each of the flow tubes (1) is provided with one of the electrodes (2) so that the plurality of electrodes (2) are distributed in a circumferential direction; The inlet / outlet flanges (3) are respectively connected to the inlet / outlet ends of the plurality of flow pipes (1).

2. An ohmic electric heater for high voltage applications as claimed in claim 1, characterized in that: The circulation pipe (1) is a spiral steel pipe, and the inner surfaces of the spiral steel pipe and the inlet / outlet flange (3) also include a high temperature resistant and high voltage resistant insulating coating.

3. An ohmic electric heater for high voltage applications as claimed in claim 2, characterized in that: The insulating coating is made of an inorganic insulating material with high dielectric strength and high insulation performance.

4. An ohmic electric heater for high voltage applications as claimed in claim 2, characterized in that: The thermal expansion coefficient of the insulating coating is close to the thermal expansion coefficient of the spiral steel pipe.

5. An ohmic electric heater for high voltage applications as claimed in claim 1, characterized in that: The number of the circulation tubes (1) arranged is three, and the number of the electrodes (2) arranged correspondingly is three; the three electrodes (2) are connected to the power supply A line, B line and C line respectively.

6. An ohmic electric heater for high voltage applications as claimed in claim 5, characterized in that: The inlet / outlet end of the flow pipe (1) near the inlet / outlet flange (3) also includes an electrode 2 connected to the power supply N line, the structure of the electrode 2 is the same as that of the electrode 1 (2), and the inlet / outlet flanges (3) are respectively grounded.

7. An ohmic electric heater for high voltage applications as claimed in claim 1, characterized in that: The electrode 1 (2) comprises: a circular electrode plate (21), a column terminal (22), a ceramic insulating sleeve (23) and a flow guide hole (24); the column terminal (22) is provided on the top of the circular electrode plate (21), the column terminal (22) also includes the ceramic insulating sleeve (23) sleeved thereon, and the circular electrode plate (21) also includes a plurality of flow guide holes (24) evenly arranged in a circumferential array.

8. An ohmic electric heater for high voltage applications as claimed in claim 7, characterized in that: Each of the circulation pipes (1) also includes an integrally formed and welded mounting metal pipe (4), and the mounting metal pipe (4) is used for inserting and mounting the ceramic insulating sleeve (23).

9. An ohmic electric heater for high voltage applications as claimed in claim 8, characterized in that: It also includes a thickened pipe section (5) arranged at the bottom of the installation metal pipe (4), the two ends of the thickened pipe section (5) being connected to the flow pipe (1) by means of a diameter change, and the circular electrode plate (21) is installed and accommodated through the thickened pipe section (5).

10. An ohmic electric heater for high voltage applications as claimed in claim 7, characterized in that: It also includes a power connection box and a temperature sensor; the connection terminal of the power connection box is connected to the column terminal (22) of the electrode 1 (2); the temperature sensor is arranged outside the circulation tube (1); The fluid flowing into the circulation tube (1) is a conductive medium, and the length and the circulation cross-sectional area of ​​the circulation tube (1) are both adjustable.

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