CN214699730U

CN214699730U - Heating device penetrates in variable frequency pipeline

Info

Publication number: CN214699730U
Application number: CN202023207340.1U
Authority: CN
Inventors: 钱洪霞
Original assignee: Tianjin Longhao Fengrui Technology Co ltd
Current assignee: Tianjin Longhao Fengrui Technology Co ltd
Priority date: 2020-12-21
Filing date: 2020-12-21
Publication date: 2021-11-12
Anticipated expiration: 2030-12-21

Abstract

The utility model discloses a wear heating device in frequency conversion pipeline, the pipeline comprises a pipeline, the cable conductor has been worn in the pipeline, the both ends of cable conductor with the tie point of pipeline is connected, the electric return circuit that cable conductor and pipeline formed is supplied power by frequency conversion device, the cable conductor with be provided with sealing mechanism between the pipeline, carry liquid, gaseous state or mixed medium in the pipeline. The utility model discloses compare with current power frequency electricity interior poling heating heat preservation technique, this device inverter circuit is simple, the fault rate is low, long service life, 300Hz above power supply circuit inductance increase, except interior cable copper loss of wearing, the whole effects of effective electric power are on the pipeline, make pipeline electromagnetic induction self generate heat, the conveying resistance is little, the thermal efficiency, the heat utilization efficiency is high, three-phase current is balanced, the return circuit electric current is little (interior heating circuit electric current of wearing is less than 80A under the 30w/m power density), the security is high, power density promotes easily, needn't dig out the pipeline during the construction, do not destroy the pipeline and keep warm.

Description

Heating device penetrates in variable frequency pipeline

Technical Field

The utility model belongs to the technical field of the pipeline heating heat preservation in crude oil collection field of defeated, and especially, relate to a wear heating device in the frequency conversion pipeline.

Background

The existing electric heating heat preservation technology of the crude oil gathering and transportation pipeline mainly comprises an external application type and a power frequency internal penetration type, wherein the external application type refers to a self-temperature-limiting heat tracing band, MI mineral insulated wires, carbon fiber cables and the like, the external application type is laid close to the pipeline during construction and is transmitted to the pipeline by self heating;

the working principle of the power frequency internal-penetration type heating and heat-insulating technology is that a cable is electrified with power frequency alternating current to heat the cable, and meanwhile, a pipeline heats due to current and induction, because the power frequency is 50HZ low in frequency, the inductive reactance of a heating loop penetrating in the pipeline is very low, the induction heating proportion is very small, most of the heating is current heating, the three-phase power supply load is seriously unbalanced, the connection between the cable and the pipeline is seriously ablated due to large current of the internal-penetration cable, the power density generally exceeds 120A at 30w/m, and the power density is limited by the limit and is difficult to be increased.

Therefore, in order to solve various problems of the existing pipeline electric heating heat preservation technology, a novel pipeline electric heating heat preservation technology is urgently needed in the industry.

SUMMERY OF THE UTILITY MODEL

In order to achieve the purpose, the technical scheme adopted by the utility model is that the utility model provides a heating device for penetrating in a frequency conversion pipeline, which comprises a pipeline, wherein a cable is penetrated in the pipeline, two ends of the cable are connected with connecting points of the pipeline, a frequency conversion device is arranged on the cable, and a sealing mechanism is arranged between the cable and the pipeline;

the frequency conversion device comprises: the frequency conversion transformer and the frequency conversion controller;

the frequency conversion transformer is connected with the cable in series, and the frequency conversion controller is connected with the frequency converter transformer;

the sealing mechanism includes: a cable gland;

the cable sealing joint is sleeved on the cable and arranged on the pipeline, and the pipeline is connected with the cable sealing joint in a sealing mode.

Preferably, the loop current of the cable is an alternating current of 300Hz or more.

Preferably, the inverter circuit IGBT of the variable frequency controller adopts asymmetrical driving.

Preferably, the cable line is a single-core cable or a multi-core cable connected in parallel.

Preferably, the cable passes through the conduit, and the cable and the conduit are connected together to form an electrical circuit.

Compared with the prior art, the utility model has the advantages of positive effect lie in, 1) wear the pipeline heating heat preservation technique to compare in with current power frequency electricity, this device inverter circuit is simple, the fault rate is low, long service life, power supply circuit inductive reactance increase more than 300Hz, except interior cable copper loss of wearing, effective electric power is whole to be used in on the pipeline, make pipeline electromagnetic induction self generate heat, the conveying resistance is little, the thermal efficiency, the heat utilization rate is high, three-phase current balance, loop current is little (interior heating circuit current of wearing is less than 80A under the 30w/m power density), the security is high, power density promotes easily, needn't dig out the pipeline during the construction, do not destroy the pipeline and keep warm.

2) The IGBT full-bridge structure is used for frequency conversion inversion of the device, unique asymmetric driving enables transformer energy feedback not to charge a filter capacitor, direct-current voltage rising is avoided, a frequency conversion device voltage monitoring and discharging circuit is also omitted, discharging loss is avoided, circuit design is simplified, reliability is higher, and failure rate is low.

3) The device completely utilizes the electricity to generate heat by the magnetic induction pipeline, so that the friction resistance of conveying high-viscosity media is reduced, and the conveying efficiency is higher.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 is a schematic structural diagram of a system of a variable frequency pipeline internal heating device provided in this embodiment;

fig. 2 is a diagram of a frequency conversion inverter main circuit of a heating device penetrating through a frequency conversion pipeline according to the embodiment;

fig. 3 is a timing diagram illustrating driving of a variable frequency heating apparatus penetrating through a pipeline according to this embodiment;

fig. 4 is another timing chart of driving a variable frequency heating apparatus penetrating through a pipeline according to this embodiment;

shown in the figure: 1. a pipeline; 2. a cable wire; 3. a connection point; 4. a variable frequency transformer; 5. a variable frequency controller; 6. the cable seals the joint.

Detailed Description

In order to make the above objects, features and advantages of the present invention more clearly understood, the present invention will be further described with reference to the accompanying drawings and examples. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the present invention is not limited to the limitations of the specific embodiments of the present disclosure.

In the embodiment, as can be seen from fig. 1 to 4 of the specification, the variable frequency pipeline inner-penetrating heating device comprises a pipeline 1, wherein a cable 2 penetrates through the pipeline 1, two ends of the cable are connected with connection points 3 of the pipeline 1, a variable frequency mechanism is arranged on the cable 2, and a sealing mechanism is arranged between the cable 2 and the pipeline 1;

the frequency conversion device comprises: a variable frequency transformer 4 and a variable frequency controller 5;

the variable frequency transformer 4 is connected with the cable 2 in series, and the variable frequency controller 5 is connected with the variable frequency transformer;

the sealing mechanism includes: a cable gland 6;

the cable sealing joint 6 is sleeved on the cable 2 and arranged on the pipeline 1, and the pipeline 1 is connected with the cable sealing joint 6 in a sealing mode.

In the scheme, the loop current of the cable 2 is alternating current with the frequency of more than 300Hz, the inverter circuit IGBT of the frequency conversion controller 5 adopts asymmetric driving, the cable 2 is a single-core cable or a multi-core cable which are connected in parallel, the cable 2 penetrates through the pipeline 1, and the cable 2 and the pipeline 1 are connected together to form an electric loop;

as shown in FIG. 2, the variable frequency controller comprises a Q1 rectifier bridge, a C1 filter capacitor, T1-T4 power devices IGBT and reverse diodes D1-D4 inside the IGBT power devices. Three-phase alternating currents L1, L2 and L3 are filtered into smooth direct currents through Q1 rectification C1, and IGBT power devices T1-T4 drive switches according to the time sequence shown in the figure 3.

As shown in fig. 3, in the GBT power device driving timing, T1 time T1 and T4 are turned on, current flows through T1 transformers B and T4, T2 time T1 is turned off, T4 is turned on continuously, and transformer feedback current is discharged through loops T4 and D3. the T3 times T1-T4 are all off, which is a dead time that prevents T1, T3, T2, T4 from sharing.

And T4 is conducted at the time T2 and T3, the current flows reversely from the T2 transformer B and flows through the T3, the T5 is closed at the time T2, the T3 is continuously conducted, and the feedback current of the transformer is discharged through a loop of the T3 and the D4. T6 times T1-T4 are all off, which is a dead time that prevents T1, T3, T2, T4 from sharing. Due to the existence of the time t2 and the time t5, the feedback energy of the transformer B does not charge the capacitor C1 any more, the rise of the direct-current voltage is avoided, and a direct-current voltage detection and discharge device is also omitted.

Fig. 4 is a variation of fig. 3, functioning in the same way, with transformer feedback current bleeding through T1, D2 and T2, D1. The output power can be changed by changing the widths of t1 and t 4.

Since the on-times of upper arms T1, T2 and lower arms T3, T4 are different, the switching timing is said to be "asymmetric".

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in other forms, and any person skilled in the art may use the above-mentioned technical contents to change or modify the equivalent embodiment into equivalent changes and apply to other fields, but any simple modification, equivalent change and modification made to the above embodiments according to the technical matters of the present invention will still fall within the protection scope of the technical solution of the present invention.

Claims

1. A heating device for frequency conversion pipeline inner penetration comprises a pipeline (1), and is characterized in that a cable (2) penetrates through the pipeline (1), two ends of the cable (2) are connected with a connection point (3) of the pipeline (1), a frequency conversion mechanism is arranged on the cable (2), and a sealing mechanism is arranged between the cable (2) and the pipeline (1);

the frequency conversion mechanism comprises: a variable frequency transformer (4) and a variable frequency controller (5);

the variable-frequency transformer (4) is connected with the cable (2) in series, and the variable-frequency controller (5) is connected with the variable-frequency transformer (4);

the sealing mechanism includes: a cable gland (6);

cable sealing joint (6) suit is in on electric cable (2) and set up on pipeline (1), pipeline (1) with sealing connection between cable sealing joint (6).

2. A variable frequency heating device for pipelines penetrating through an inner wall as claimed in claim 1, wherein the loop current of the cable (2) is an alternating current of 300Hz or more.

3. A variable frequency in-pipe heating device according to claim 1, wherein the inverter circuit IGBT drive of the variable frequency controller (5) is an asymmetric drive.

4. A variable frequency heating device for pipes passing therethrough according to claim 1, wherein the cable line (2) is a single core cable.

5. A variable frequency conduit inner-penetration heating apparatus as claimed in claim 1, wherein the cable (2) penetrates through the conduit (1), and the cable (2) and the conduit (1) are connected together to form an electric loop.