WO2019054585A1 - Device for controlling thyristor firing by using three-phase voltage ratio, and control method thereof - Google Patents

Abstract

A device for controlling thyristor firing by using a three-phase voltage ratio according to an embodiment of the present invention may comprise: a three-phase ratio waveform generator for generating a ratio waveform by calculating ratios of absolute values of respective three-phase line voltages having a constant phase difference with respect to a sum of the absolute values of the three-phase line voltages; and a firing pulse generator for comparing a control firing angle input from a controller with one waveform selected from among the three-phase ratio waveforms, and outputting a firing pulse of the thyristor.

Description

Thyristor ignition control device using three-phase voltage ratio and control method thereof

The present invention relates to a thyristor ignition control device using a three-phase voltage ratio and a control method thereof.

The thyristor, which is mainly used as a device of large-capacity power conversion device of power generation facilities, turns on the device by applying a pulse to the gate due to the characteristics of the device, applies a reverse voltage across the anode and the cathode, (turn off). Although there are many firing methods for turning on the thyristor, in the case of a phase control rectifier that receives 60 Hz AC power from the system and converts it into DC power, it is generally operated by a counter (integrator) And a control pulse is output at a point where the triangular wave crosses the control signal expressed by a point angle of 0 DEG to 180 DEG.

However, since the counter method needs to perform complicated calculations such as an integral calculation and a DFT calculation, it is necessary to optimize the scheduling by using a high-performance microprocessor and satisfy the execution cycle requirement of the control calculation required for the motor control.

It is an object of the present invention to provide a thyristor jumper control device capable of outputting a jumper pulse at an accurate phase even at the initial startup of the system and capable of quickly controlling the thyristor even using a low- And the like.

The thyristor ignition control system using the three-phase voltage ratio according to an embodiment of the present invention calculates the ratio of the absolute value of each three-phase line voltage to the sum of the absolute values of the three-phase line voltages having a constant phase difference, And a count pulse generator for outputting a count pulse of the thyristor by comparing a selected one of the three-phase ratio waveform and the control point pulse angle input from the controller.

The thyristor ignition control method using the three-phase voltage ratio according to an embodiment of the present invention calculates the ratio of the absolute value of each three-phase line voltage to the sum of the absolute values of the three-phase line voltages having a constant phase difference Generating a ratio waveform, and outputting an impulse pulse of the thyristor by comparing a control point input from the controller with a selected one of the three-phase ratio waveforms.

The thyristor ignition control device using the three-phase voltage ratio according to the embodiment of the present invention can output the ignition pulse in the correct phase even at the initial startup of the system and can quickly output the ignition pulse even when the low- You can control the arcade.

1 is a diagram showing a configuration of a thyristor ignition control device using a three-phase voltage ratio.

2 is an operational logic diagram of a three-phase-ratio waveform generator.

3 is a graph of output of a three-phase line voltage and a three phase ratio waveform generator.

4 is an operational logic diagram of the control point tilt section discriminator.

5 is an operational logic diagram of the increment window generator.

6 is an operational logic diagram of the thyristor (1, 4) increment pulse generator.

7A is a diagram showing the results of the increment pulse output of the counter system.

7B is a diagram showing pulse output results of the increment pulse generator according to the embodiment of the present invention.

8 is a flowchart showing a thyristor ignition control method using a three-phase voltage ratio.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals even though they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. Also, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

1 shows a configuration of a thyristor ignition control device using a three-phase voltage ratio.

1, a thyristor turn-off control device 1 according to an embodiment of the present invention includes a three-phase ratio waveform generator 100, a control point tilter section discriminator 200, an increment window generator 300, A pulse generator 400, and a plurality of thyristors 500 (six thyristors in one embodiment of the invention).

The three-phase-ratio waveform generator 100 generates a ratio waveform by calculating the ratio of the absolute value of each three-phase line voltage to the sum of absolute values of three-phase line voltages having a constant phase difference. That is, the ratio of the absolute value of each three-phase line voltage to the sum of the absolute values of the three-phase line voltages V _AC , V _BA , and V _CB is calculated by the following equation (1).

(Equation 1)

As shown in Equation (1) above, the sum of the absolute values of the three-phase line voltages represents the sum of the absolute values of the three-phase line voltages. R _AC represents the ratio of the absolute value of V _{AC to} the sum of absolute values of three-phase line voltages, R _BA represents the ratio of absolute values of V _{BA to} the sum of absolute values of three-phase line voltages, and R _CB Represents the ratio of the absolute value of V _{CB to} the sum of absolute values of three-phase line-to-line voltages.

FIG. 2 is a calculation logic diagram of a three-phase-ratio waveform generator, and shows a process of generating a ratio waveform of a three-phase line-to-line voltage through Equation 1. FIG. The specific calculation process is as follows.

First, each three-phase line voltage V _AC , V _BA , and V _CB are input. Next, the absolute values of the line-to-line voltages are obtained (110a to 110c), the absolute values of the absolute values are summed (120), and the sum of the absolute values of the three-phase line voltages is obtained (130). The absolute values of the line voltages obtained previously are divided by the sum of the absolute values of the three-phase line voltages (140a to 140c), and the ratio waveforms R _AC , R _BA , R _CB are generated (150a to 150c).

In the present embodiment, the generation of the three-phase ratio waveform is implemented in a hardware manner through a logic circuit. However, the present invention is not limited to this, and may be implemented in software.

The ratio value calculated from the three phase ratio waveform generator has a value between 0 and 0.5 irrespective of the variation of the line voltage amplitude. As shown in the output graph of the 3-phase line voltage generator and the 3-phase ratio waveform generator of FIG. 3, the output value of the 3-phase ratio waveform generator varies from 0 to 0.5 while the phase of the line voltage varies from 0 to 60 degrees. And has a constant value of 0.5 at 60 ° to 120 °, and a constant slope from 0.5 to 0 at 120 ° to 180 °.

Therefore, as shown in [Table 1] below, it is possible to express the linear phase of the line voltage by combining the three ratio waveforms which are the outputs of the three-phase ratio waveform generator. For example, in the case of V _AC, the three ratio waveforms R _AC (0 ° to 60 °), R _CB (60 ° to 120 °), and R _BA (120 ° to 180 °) The phase of 0 ° to 180 ° can be expressed linearly.

The control point wobble interval determination unit 200 determines where the control point wobble input from the controller belongs to the preset interval. Specifically, as shown in [Table 2], it plays a role of determining which of the following three cases the control point angle inputted from the controller is, and outputting. The process of determining and outputting the value of each interval according to the control point angle in the control point horn section discriminator is shown in the arithmetic logic diagram of FIG.

4, when the control point angle? From the controller is input to the control point angle range discriminator, the input control point angle is 0??? <60, 60??? <120 , And 120 占?? <180 占 (210a to 210c, 220a and 220b, 230a and 230b). If it is determined that the control point tilt angle belongs to one of the three ranges, the value of the control tilt angle is converted by the data type transformation 240a to 240c and the gain is multiplied by 250a and 250b, (270).

In the present embodiment, it has been described that the interval of the control point angle is implemented in a hardware manner through a logic circuit, but the present invention is not limited thereto and may be implemented in software.

Firing the window generator 300, as shown in Figure 5, a period in which thyristor is turned on for each line-to-line voltage V _AC, V _BC , V _BA , V _CA , V _CB , V _AB is configured to output a TRUE value only during a positive interval with a value greater than zero.

Referring to FIG. 5, the line voltage V _AC , W _AC , W _BA , and W _CB are output as the TRUE values (330a, 330c, and 330e) when V _BA and V _CB have positive values greater than zero (310a to 310c), respectively. If the line voltage V _AC , When V _BA and V _CB are smaller than 0 (320a to 320c), the line voltage V _CA , W _CA , W _AB , and W _BC as output values for V _AB and V _BC , respectively (330b, 330d, and 330f).

The increment pulse generator 400 compares a selected one of the three-phase ratio waveforms and the control point angle input from the controller, and outputs the increment pulse of the thyristor. Specifically, based on [Table 3], one of the three ratio waveforms R _AC , R _CB , and R _BA generated by the three-phase ratio waveform generator is selected according to the output value of the control point trough section discriminator, And outputs control pulses of the six thyristors constituting the power converter in comparison with the control point whistle.

3 phase ratio The output value of the waveform generator has a value of 0 to 0.5 while the phase of the 3-phase line voltage varies from 0 ° to 60 °. Therefore, in order to adjust the scale to the unit of radian, The output factor of the 3-phase ratio waveform generator is multiplied by the derived scale factor.

(Equation 2)

Since the ratio waveform compared with the control point angle is composed of three waveforms including phase information at intervals of 60 °, the control point angle is 60 ° to 120 ° to limit the range of 0 ° to 180 ° to 0 ° to 60 ° Subtract 60 ° when you have a value between 120 ° and 180 ° and subtract 120 ° when you have a value between 120 ° and 180 °. Also, multiply by π / 180 to convert the control point angle expressed in degrees to radians.

Wherein the increment pulse generator selects one of the ratio waveforms generated by the three-phase ratio waveform generator according to the output value of the control point and the angle conversion value of the ratio waveform, And generates a control pulse at a time point larger than the control point tilt angle. That is, the control point excitation angle converted to the radian unit is compared with the output value of the 3-phase ratio waveform generator, and the arc pulse is generated at the time when the angle conversion value of the ratio waveform crosses the control point angle. This is ANDed with the output of the window generator to output a pulse to the thyristor only when the window is TRUE (ie, when the line voltage has a positive value greater than zero).

For example, referring to Table 3 above, when the control point angle input from the controller at the time of switching the second thyristor is 90 degrees, the value obtained by multiplying the R _BA value by the conversion coefficient (angle conversion value of the ratio waveform) The control point is converted into a radian unit, and a control pulse is generated at a point where the two values cross each other. At this time, if the output value W _BC of the incremental window generator is TRUE, the pulse is output to the second thyristor.

As an example of the incremental pulse generator according to one embodiment of the present invention having the above-described configuration, the operation logic diagram of the incremental pulse generator in thyristors 1 and 4 is shown in FIG.

Referring to FIG. 6, first of all, subtracting 60 ° and 120 ° (410a and 410b) for each case to make the range of the control point angle α input from the controller 0 ° to 60 °, (430a to 430c). On the other hand, R _AC , R _CB , and R _BA output from the three-phase ratio waveform generator are multiplied by the conversion coefficient described above and converted into radians (420a to 420c). After the angle conversion value of the ratio waveform is compared with the control point angle, the width of the pulse is determined through monostable processing in the case where the angle conversion value of the ratio waveform is larger than the control point angle (440a to 440c) 450c, and an increment pulse. (460a and 460b) by performing an AND operation on the output value of the incremental window generator, and outputs the incremental pulse to the thyristor only when the incremental window has the TRUE value (the interval in which the inter-line voltage has a positive value).

The arithmetic logic circuit of the above-mentioned incremental pulse generator can be implemented with the same configuration for the remaining pairs of thyristors (2, 5 and 3, 6), and a detailed description thereof will be omitted.

Fig. 7A is a diagram showing the result of the increment pulse output (control point whistle angle: 100 DEG) of the counter system. In the case of the counter method, since the integrator is initialized at the starting point (rising edge) of the phase 0 ° of the three-phase voltage input sinusoidal wave, integration is performed during one cycle of the sinusoidal wave to generate a normal phase triangular wave. Therefore, there is a drawback that the triangular wave is not normally generated at the initial start of the system. 7A, it can be confirmed that the first two pulses for signaling the thyristor are not normally output in the case of the counter method.

7B is a diagram showing a pulse output result (control point whorl angle: 100 DEG) of the increment pulse generator according to the embodiment of the present invention. Referring to the graph of FIG. 7B, it can be confirmed that the thyristor ignition control method using the three-phase voltage ratio according to the embodiment of the present invention outputs the ignition pulse in the correct phase even at the initial start of the system.

As described above, according to the thyristor ignition control apparatus using the three-phase voltage ratio according to the embodiment of the present invention, it is possible to output the ignition pulse in the correct phase even at the initial startup of the system, It is possible to generate a ratio waveform including phase information by using only simple operations such as multiplication, division and absolute value operation without using a complicated operation which acts as a large load, and it is possible to use a low- There is an advantage to control the index.

8 is a flowchart showing a thyristor ignition control method using a three-phase voltage ratio.

First, a ratio waveform is generated by calculating the ratio of the absolute value of each three-phase line voltage to the sum of the absolute values of the three-phase line voltages V _AC , V _BA , and V _CB by the three-phase ratio waveform generator (S100).

When the control point tilt angle is input from the controller (S110), the control point tilt angle range discriminator determines which of the preset sections the input control point tilt angle belongs to (S120).

The increment pulse generator selects one waveform of the ratio waveforms R _AC , R _CB , and R _BA generated by the three-phase ratio waveform generator according to the output value of the control point and the conversion factor calculated according to the formula 2 described above And converts the ratio waveform into angle conversion in units of radians (S200).

Then, the angle conversion value of the ratio waveform is compared with the control point angle input from the controller, and a control pulse is generated at a point in time when the angle conversion value of the ratio waveform becomes larger than the control point angle (S300). At this time, when the output value of the increment window generator indicates TRUE (S400), the thyristor outputs the increment pulse (S500).

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them.

Although not shown, the configurations of the present invention may be implemented by a computer program, and may include a memory for storing a computer program and a processor such as a CPU for executing a computer program stored in the memory to perform the functions of each configuration There will be.

Furthermore, the terms "comprises", "comprising", or "having" described above mean that a component can be implanted unless otherwise specifically stated, But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (10)

1. A thyristor ignition control device comprising:

   A three-phase-ratio waveform generator for generating a ratio waveform by calculating the ratio of the absolute value of each three-phase line voltage to the sum of the absolute values of the three-phase line voltages having a constant phase difference; And

   A pulse generator for comparing the selected one of the three-phase-ratio waveforms and the control point angle input from the controller to output a pulse of the thyristor;

   And a thyristor ignition control unit.
2. The method according to claim 1,

   A control point toughening section discriminator for discriminating which of the preset sections the control point touched angle input from the controller belongs to;

   Further comprising a thyristor ignition control device.
3. The method of claim 2,

   Wherein the control pulse generator selects one of the ratio waveforms generated by the three-phase ratio waveform generator according to the output value of the control point and the control point tilt angle generator, Wherein the control pulse generator generates a control pulse at a time point when the control point is greater than the control point slip angle.
4. The method according to claim 1,

   And outputting a TRUE value only during a positive period in which each line voltage has a value greater than zero,

   Further comprising a thyristor ignition control device.
5. The method of claim 4,

   Wherein the ignition pulse generator outputs an ignition pulse to the thyristor only when the ignition window has a TRUE value through an AND operation with the output of the ignition window generator.
6. As a thyristor arc control method,

   Generating a ratio waveform by calculating a ratio of an absolute value of each three-phase line voltage to a sum of absolute values of three-phase line voltages having a constant phase difference; And

   Comparing the waveform of the selected one of the control point tilt angle input from the controller and the three-phase ratio waveform and outputting the ignition pulse of the thyristor

   Wherein the thyristor is controlled by the thyristor.
7. The method of claim 6,

   Further comprising the step of determining where the control point angle input from the controller belongs to a predetermined section.
8. The method of claim 7,

   Wherein the step of outputting the control pulse comprises the steps of: selecting one of the ratio waveforms generated by the three-phase ratio waveform generator according to the output value of the control point tilt section discriminator, comparing the waveform with the control point tilt angle, And generating an ignition pulse at a time point at which the converted value becomes larger than the control point tilt angle.
9. The method of claim 6,

   And outputting a TRUE value only during a positive period in which the line voltage has a value greater than zero by an increment window generator.
10. The method of claim 9,

    Wherein the step of outputting the ignition pulse outputs an ignition pulse to the thyristor only when the ignition window has a TRUE value through an AND operation with the output of the ignition window generator.

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