96-pulse-wave phase-shifting topological structure of double 48-pulse-wave combined hydrogen production rectifier transformer

Abstract

The invention provides a 96-pulse-wave phase-shifting topological structure of a double 48-pulse-wave combined hydrogen production rectifier transformer, the 96-pulse-wave phase-shifting topological structure is formed by equivalently combining two groups of single-machine 48-pulse-wave rectifier transformers, and the two groups of single-machine 48-pulse-wave rectifier transformers are respectively a No.1 rectifier transformer and a No.2 rectifier transformer. The first rectifier transformer and the second rectifier transformer are both transformers with a left 24-pulse transformer body and a right 24-pulse transformer body, the first rectifier transformer and the second rectifier transformer are each provided with a left transformer body and a right transformer body, and under the conventional condition, eight 12-pulse rectifier transformers are creatively designed into two single-machine 48-pulse rectifier transformers which are combined to be equivalent to 96-pulse rectifier transformers for use. The overall manufacturing cost can be greatly reduced, meanwhile, the size and weight of the system are effectively reduced, and rapid development of the green hydrogen industry is facilitated.

Description

Technical Field

[0001] This article belongs to the technical field of 96-pulse thyristor rectifier transformers, and specifically relates to a 96-pulse (single machine 48-pulse) phase-shifting topology structure of a dual 48-pulse combined hydrogen production rectifier transformer. Background Art

[0002] The hydrogen-electricity coupling system includes devices such as a power grid, wind power and photovoltaic power generation equipment, user loads, hydrogen energy storage equipment, and a rectifier power supply as power sources. The real-time conversion of renewable energy into electrical energy by the wind-solar power generation equipment is the main source of electrical energy in wind-solar complementary power generation for hydrogen production. The green electrical energy is supplied to the hydrogen production electrolyzer through a hydrogen production rectifier transformer and a rectifier, and is converted into various green energy sources such as hydrogen, ammonia, and alcohol.

[0003] For the rectification device of large-scale 1000-2000 Nm3 / h electrolytic water hydrogen production, a multi-pulse thyristor rectification system is usually adopted. The main types of rectifier transformers include a 6-pulse three-phase double reverse star structure with a balance reactor, a valve side star-delta phase-shifting 12-pulse structure, a grid side phase-shifting + valve side star-delta phase-shifting 24-pulse structure, etc.; the current harmonic of a single 24-pulse is 5-6%, and the voltage harmonic is 0.9%. The power factor of this system is ≥0.95. In order to improve the system power factor and reduce the harmonic content, a multi-pulse thyristor rectification system needs to add a filtering device to achieve relatively ideal current and voltage harmonics. This conventional technology has a high investment and a large floor area, which is not conducive to the industrial promotion of green hydrogen. Summary of the Invention

[0004] To solve the above problems, this paper proposes a 96-pulse phase-shifting topology for a dual 48-pulse combined hydrogen production rectifier transformer. The 96-pulse phase-shifting topology is equivalently constituted by combining two single-unit 48-pulse rectifier transformers. The two single-unit 48-pulse rectifier transformers are the first rectifier transformer and the second rectifier transformer respectively. Both the first rectifier transformer and the second rectifier transformer are transformers with left and right double 24-pulse cores. The first rectifier transformer and the second rectifier transformer are respectively provided with a left core and a right core. The left and right cores of the first rectifier transformer and the second rectifier transformer are all composed of a high-voltage winding connected in D, a low-voltage winding connected in d, and a low-voltage winding connected in y to form 24 pulses. The phase-shifting angles of the high-voltage winding D connection of the left core of the first rectifier are +1.875° and -13.125°, and the phase-shifting angles of the high-voltage winding D connection of the right core of the first rectifier are +5.625° and -9.375°. The phase angle difference of 3.75° between the left and right two 24-pulse cores of the first rectifier is equivalently combined into 48 pulses. The phase-shifting angles of the high-voltage winding D connection of the left core of the second rectifier are -1.875° and +13.125°, and the phase-shifting angles of the high-voltage winding D connection of the right core of the second rectifier are -5.625° and +9.375°. The phase angle difference of 7.5° between the left and right two 24-pulse cores of the second rectifier is equivalently combined into a 48-pulse rectifier transformer. The phase angle difference of 3.75° between the first rectifier transformer and the second rectifier transformer is equivalently combined into a 96-pulse rectifier transformer. The 96-pulse (single-unit 48-pulse) thyristor rectifier transformer can not only realize the wide-range and convenient adjustment of the valve-side voltage through the on-load tap-changer, but also achieve extremely low current and voltage harmonics, improve the power factor and efficiency of the system, meet the current requirements of large-scale 500 - 2000 Nm3 / h caustic soda solution and ALK electrolyzers, facilitate the industrialization of green hydrogen, and have higher promotion value. The innovative design of 8 conventional 12-pulse rectifier transformers into 2 single-unit 48-pulse rectifier transformers equivalently combined into 96 pulses can not only greatly reduce the overall cost, but also effectively reduce the volume and weight of the system.

[0005] The left and right cores of the first rectifier transformer and the second rectifier transformer are both upper and lower separated double cores. There are conjugate iron cores between the upper and lower parts of the left and right cores of the first rectifier transformer and the second rectifier transformer. The conjugate iron core can provide an additional magnetic path for the upper and lower core column fluxes under different phase conditions, that is, it realizes the magnetic isolation and independent operation of the upper and lower two groups of windings, and at the same time effectively reduces the volume and weight of the system.

[0006] The phase shift angle of the D-connection of the high-voltage winding at the upper part of the left body of the No. 1 rectifier transformer is +1.875°, the phase shift angle of the D-connection of the high-voltage winding at the lower part of the left body of the No. 1 rectifier transformer is -13.125°, the phase shift angle of the D-connection of the high-voltage winding at the upper part of the right body of the No. 1 rectifier transformer is +5.625°, and the phase shift angle of the D-connection of the high-voltage winding at the lower part of the right body of the No. 1 rectifier transformer is -9.375°.

[0007] The phase shift angle of the D-connection of the high-voltage winding at the upper part of the left body of the No. 2 rectifier transformer is -1.875°, the phase shift angle of the D-connection of the high-voltage winding at the lower part of the left body of the No. 2 rectifier transformer is +13.125°, the phase shift angle of the D-connection of the high-voltage winding at the upper part of the left body of the No. 2 rectifier transformer is -5.625°, and the phase shift angle of the D-connection of the high-voltage winding at the lower part of the left body of the No. 2 rectifier transformer is +9.375°.

[0008] The single-unit 48-pulse rectifier transformer is equipped with 8 sets of electrically independent three-phase valve-side windings. The phase angle difference between the four delta-connected and four star-connected valve-side windings of the single-unit 48-pulse rectifier transformer is 30°. The magnetic circuits and electrics of one delta-connected and one star-connected valve-side winding at the lower part of the left body and one delta-connected and one star-connected valve-side winding at the upper part are completely independent, forming a set of 24 pulses. The magnetic circuits and electrics of one delta-connected and one star-connected valve-side winding at the lower part of the right body and one delta-connected and one star-connected valve-side winding at the upper part are completely independent, forming another set of 24 pulses. The combination of the four delta-connected and four star-connected valve-side windings is equivalent to 48 pulses, realizing the independent operation of 8 sets of valve-side windings of the single unit, effectively reducing the volume and weight of the system.

[0009] Beneficial effects:

[0010] The 96-pulse (48 pulses for a single unit) thyristor rectifier transformer can not only achieve wide-range and convenient adjustment of the valve-side voltage through the on-load tap-changer, but also achieve extremely low current and voltage harmonics, improve the power factor and efficiency of the system, can meet the current demand of large-scale 500 - 2000 Nm3 / h caustic soda solution and ALK electrolyzers, is conducive to the industrialization of green hydrogen, and has higher promotion value.

[0011] Innovatively designing 8 sets of 12-pulse rectifier transformers in the conventional case into a combination of 2 sets of single-unit 48-pulse rectifier transformers equivalent to 96 pulses for use can not only greatly reduce the overall cost, but also effectively reduce the volume and weight of the system, which is beneficial to the rapid development of the green hydrogen industry.

[0012] The conjugate iron core can provide an additional magnetic circuit for the magnetic fluxes of the upper and lower core columns under different phase conditions, that is, it realizes the magnetic isolation and independent operation of the upper and lower two groups of windings, and at the same time effectively reduces the volume and weight of the system. Description of the drawings

[0013] Figure 1It is the system schematic diagram of the 96-pulse (48 pulses for a single unit) phase-shifted topology;

[0014] Figure 2 It is the schematic diagram of the combined operation of two 48-pulse units in the 96-pulse (48 pulses for a single unit) phase-shifted topology;

[0015] Figure 3 It is the schematic diagram of the positive phase angle of the connection between the high-voltage winding and the low-voltage winding of the left body of the first rectifier transformer;

[0016] Figure 4 It is the schematic diagram of the negative phase angle of the connection between the high-voltage winding and the low-voltage winding of the left body of the first rectifier transformer;

[0017] Figure 5 It is the schematic diagram of the positive phase angle of the connection between the high-voltage winding and the low-voltage winding of the right body of the first rectifier transformer;

[0018] Figure 6 It is the schematic diagram of the negative phase angle of the connection between the high-voltage winding and the low-voltage winding of the right body of the first rectifier transformer;

[0019] Figure 7 It is the schematic diagram of the negative phase angle of the connection between the high-voltage winding and the low-voltage winding of the left body of the second rectifier transformer;

[0020] Figure 8 It is the schematic diagram of the positive phase angle of the connection between the high-voltage winding and the low-voltage winding of the left body of the second rectifier transformer;

[0021] Figure 9 It is the schematic diagram of the negative phase angle of the connection between the high-voltage winding and the low-voltage winding of the right body of the second rectifier transformer;

[0022] Figure 10 It is the schematic diagram of the positive phase angle of the connection between the high-voltage winding and the low-voltage winding of the right body of the second rectifier transformer;

[0023] Figure 11 It is the schematic diagram of the phase difference integration of the first rectifier transformer;

[0024] Figure 12 It is the schematic diagram of the phase difference integration of the second rectifier transformer;

[0025] In the figure: 1. The first rectifier transformer, 2. The second rectifier transformer. Specific embodiments

[0026] To deepen the understanding of the present invention, the present invention will be further described in detail below in combination with embodiments and drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0027] The first rectifier transformer 1, the second rectifier transformer 2

[0028] As shown in Figure 1 , 2 , 3, 4, 5, 6, 7, 8, 9, 10, 11, 12;

[0029] A 96-pulse phase-shifting topology of a dual 48-pulse combined hydrogen production rectifier transformer, where the 96-pulse phase-shifting topology is equivalently composed of a combination of two single-machine 48-pulse rectifier transformers. The two single-machine 48-pulse rectifier transformers are the first rectifier transformer 1 and the second rectifier transformer 2 respectively. Both the first rectifier transformer 1 and the second rectifier transformer 2 are transformers with a left and right double 24-pulse cores. The first rectifier transformer 1 and the second rectifier transformer 2 are respectively provided with a left core and a right core. The left and right cores of the first rectifier transformer 1 and the second rectifier transformer 2 are all combined with a high-voltage winding D connection, a low-voltage winding d connection, and a low-voltage winding y connection to form 24 pulses. The phase-shifting angles of the high-voltage winding D connection of the left core of the first rectifier are +1.875° and -13.125°, and the phase-shifting angles of the high-voltage winding D connection of the right core of the first rectifier are +5.625° and -9.375°. The phase angle difference of 3.75° between the left and right two 24-pulse cores of the first rectifier is equivalently combined into 48 pulses. The phase-shifting angles of the high-voltage winding D connection of the left core of the second rectifier are -1.875° and +13.125°, and the phase-shifting angles of the high-voltage winding D connection of the right core of the second rectifier are -5.625° and +9.375°. The phase angle difference of 7.5° between the left and right two 24-pulse cores of the second rectifier is equivalently combined into a 48-pulse rectifier transformer. The phase angle difference of 3.75° between the first rectifier transformer 1 and the second rectifier transformer 2 is equivalently combined into a 96-pulse rectifier transformer. The left and right cores of the first rectifier transformer 1 and the second rectifier transformer 2 are both upper and lower separated double cores. There are conjugate iron cores between the upper and lower parts of the left and right cores of the first rectifier transformer 1 and the second rectifier transformer 2. The single-machine 48-pulse rectifier transformer is provided with 8 sets of electrically independent three-phase valve-side windings. The phase angle difference between the four low-voltage winding d connections and the four low-voltage winding y connection valve-side windings of the single-machine 48-pulse rectifier transformer is 30°. The magnetic circuit and electricity of one d connection and one y connection valve-side winding in the lower part of the left core and one d connection and one y connection valve-side winding in the upper part are completely independent, forming a group of 24 pulses. The magnetic circuit and electricity of one d connection and one y connection valve-side winding in the lower part of the right core and one d connection and one y connection valve-side winding in the upper part are completely independent, forming another group of 24 pulses. The combination of four d connection and four y connection valve-side windings is equivalently combined into 48 pulses.

[0030] Implementation example;

[0031] The phase shift angle of the D connection of the high-voltage winding at the upper part of the left body of the first rectifier transformer 1 is +1.875°, the phase shift angle of the D connection of the high-voltage winding at the lower part of the left body of the first rectifier transformer 1 is -13.125°, the phase shift angle of the D connection of the high-voltage winding at the upper part of the right body of the first rectifier transformer 1 is +5.625°, and the phase shift angle of the D connection of the high-voltage winding at the lower part of the right body of the first rectifier transformer 1 is -9.375°.

[0032] The phase shift angle of the D connection of the high-voltage winding at the upper part of the left body of the second rectifier transformer 2 is -1.875°, the phase shift angle of the D connection of the high-voltage winding at the lower part of the left body of the second rectifier transformer 2 is +13.125°, the phase shift angle of the D connection of the high-voltage winding at the upper part of the left body of the second rectifier transformer 2 is -5.625°, and the phase shift angle of the D connection of the high-voltage winding at the lower part of the left body of the second rectifier transformer 2 is +9.375°.

[0033] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A 96-pulse phase-shift topology structure of a dual 48-pulse combined hydrogen production rectifier transformer, characterized in that: The 96-pulse phase-shifting topology structure is equivalently constituted by the combination of two groups of single-machine 48-pulse rectifier transformers. The two groups of single-machine 48-pulse rectifier transformers are respectively No. 1 rectifier transformer and No. 2 rectifier transformer. The No. 1 rectifier transformer and No. 2 rectifier transformer are both left and right double 24-pulse transformers. The No. 1 rectifier transformer and No. 2 rectifier transformer are respectively provided with a left body and a right body. The left and right bodies of the No. 1 rectifier transformer and No. 2 rectifier transformer are both high-voltage winding D-connected and low-voltage winding d-connected and low-voltage winding y-connected, forming a combination of 24 pulses. The left body high-voltage winding D-connected phase shift angle of the No. 1 rectifier is +1.875° and -13.125°. The No. 1 rectifier The right body high-voltage winding D-connected phase shift angle of the device is +5.625° and -9.375°, the phase angle difference of the left and right two 24-pulse devices of the No. 1 rectifier is 3.75°, and the combination is equivalent to 48 pulses, the left body high-voltage winding D-connected phase shift angle of the No. 2 rectifier is -1.875° and +13.125°, the right body high-voltage winding D-connected phase shift angle of the No. 2 rectifier is -5.625° and +9.375°, the left and right two 24-pulse devices of the No. 2 rectifier have a phase angle difference of 7.5°, and the combination is equivalent to a 48-pulse rectifier transformer, and the phase angle difference of the No. 1 rectifier transformer and the No. 2 rectifier transformer is 3.75°, and the combination is equivalent to a 96-pulse rectifier transformer.

2. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The left and right bodies of the No. 1 rectifier transformer and the No. 2 rectifier transformer are both double-layer bodies separated into upper and lower parts, and a conjugate iron core is provided between the upper and lower parts of the left and right bodies of the No. 1 rectifier transformer and the No. 2 rectifier transformer.

3. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The high-voltage winding D-connected phase shift angle at the upper part of the left body of the No. 1 rectifier transformer is +1.875°, and the high-voltage winding D-connected phase shift angle at the lower part of the left body of the No. 1 rectifier transformer is -13.125°.

4. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The high-voltage winding D-connected phase shift angle at the upper right body of the No. 1 rectifier transformer is +5.625°, and the high-voltage winding D-connected phase shift angle at the lower right body of the No. 1 rectifier transformer is -9.375°.

5. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The high-voltage winding D-connected phase shift angle at the upper part of the left body of the No. 2 rectifier transformer is -1.875°, and the high-voltage winding D-connected phase shift angle at the lower part of the left body of the No. 2 rectifier transformer is +13.125°.

6. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The high-voltage winding D-connected phase shift angle at the upper part of the left body of the No. 2 rectifier transformer is -5.625°, and the high-voltage winding D-connected phase shift angle at the lower part of the left body of the No. 2 rectifier transformer is +9.375°.

7. A 96-pulse phase-shifted topology structure of a dual 48-pulse combined hydrogen production rectifier transformer according to claim 1, characterized in that: The single-machine 48-pulse rectifier transformer is provided with 8 sets of electrically independent three-phase valve-side windings. The phase angle difference between the four low-voltage windings D-connected and the four low-voltage windings Y-connected valve-side windings of the single-machine 48-pulse rectifier transformer is 30°. The magnetic circuit and electrical circuit of the valve-side winding with one D-connection and one Y-connection at the lower part of the left body and the valve-side winding with one D-connection and one Y-connection at the upper part of the left body are completely independent, forming a group of 24 pulses. The magnetic circuit and electrical circuit of the valve-side winding with one D-connection and one Y-connection at the lower part of the right body and the valve-side winding with one D-connection and one Y-connection at the upper part of the right body are completely independent, forming another group of 24 pulses. The combination of four D-connected and four Y-connected valve-side windings is equivalent to 48 pulses.

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