JPS6169400A - Thyristor type rotary current transformer - Google Patents

Abstract

PURPOSE:To enhance the current transformation efficiency by rotating a commutator and a slip ring by a drive unit to commutator and reversely transform the current. CONSTITUTION:A field and an armature are removed from a rotary current transformer, the first pole of the commutator is shortcircuited to the first slip ring, and the second pole is shortcircuited to the second slip ring. When an AC is applied to the slip ring, a DC is output to the brush of the commutator. On the other hand, when a DC is applied to the brush of the commutator, an AC is output at the slip ring.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the i-current (CONVERT) of electric power, that is, the conversion from alternating current to direct current (CONVERT) (hereinafter abbreviated as Convert), and the conversion from direct current to alternating current (IN).
VER8B C0NVERT.

The present invention relates to a device for performing INVERT (hereinafter abbreviated as invert).

Conventional rotary current transformers use a conversion method of power → motion → power, which inevitably results in large energy losses.

The purpose of this invention is to make a rotary current transformer adopt a conversion method of electric power to electric power, thereby increasing its current transformation efficiency to the same level as that of a thyristor.

To do this, we first decided to remove the field and armature from the rotating current transformer. Then only the commutator and slip ring remain. The commutator of the rotary current transformer is a multi-pole commutator (a commutator with many pole pieces, that is, commutator pieces), so it is modified into a two-pole commutator. Since there are three slip rings (3 monkeys), this will be modified to two slip rings (2 items). The first pole of the commutator to the first slip ring, the second
Short-circuit the poles to the second slip ring with a conductor. This is the main body of the rotary current transformer of the present invention.

This machine requires an external drive machine. In most cases, electric motors are used with direct shaft coupling. Since this electric motor is used only to rotate the commutator and slip ring overcoming the resistance of the brushes, only a small amount of torque is required, and an extremely small electric motor is required.

How can you convert (rectify) with just this device?
Can it be done?

The two AC lines are called the black line and the white line, and if we take one period of the black line, the first π is + and the next π is -. Therefore, when the deflection is input to the first slip ring, the first pole piece becomes + at the first π and - at the next π.

It would be great if the first pole piece were in contact with the first brush during the first π and the second brush during the next π. The first brush outputs 10, and the second brush outputs -.

That's all there is to the rectification principle.

A synchronous motor rotates once per period. Even when the frequency fluctuates (that is, even when temporal expansion or contraction occurs in one period), it rotates once per period. When this strictly force-synchronous rotation (-one rotation of the frequency) directly drives the commutator, the pole piece and the brush contact each other every π, and the switching timing is shifted. Even if there are voltage fluctuations or load fluctuations), this will never occur. This is the guarantee of an accurate synchronous switch.

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The DC output is a pulsating current with double-wave rectification. If you want to make it flat, use an LC smoothing circuit or storage battery.

When inverting (reverse current transformation), apply direct current to the commutator brushes. As the first pole piece rotates,
By contacting the first brush of 10 and the second brush of 10, the 1st and 2nd brushes are sent to the first slip ring. For this reason, alternating current is output to the slip ring. This is not a sine wave alternating current, but a square wave alternating current. Therefore, the effective voltage is approximately AC 100V from input DC 100V. The frequency is determined by the rotational speed of the shaft, if 50 r, p, s then 50 Hz s 60 r, p, s fx if 6
0Hz is output.

What kind of prime mover should I use for the invert drive? The problem of frequency stability is the problem of stability of the rotational speed of the prime mover.

When performing reverse current transformation in a factory, there is a Tokyo Electric Power service lead line (maximum frequency variation 0.5%), so you can use it to turn a synchronous motor and use it as a drive machine. In that case, the output alternating current can be a fairly high quality alternating current with a frequency variation of within 0.5 degrees.

What should I do if there is no lead-in line? There is no other way than to use a DC motor.

If the direct current is a good direct current with no voltage fluctuations, it will rotate at a speed where the driving force of the DC motor and the resistance force of the thyristor rotary current transformer are balanced (balanced speed/final speed), so almost no rotation will occur. There is no speed variation, and there is almost no frequency variation of the output AC.

So what do you do when you don't have a lead-in line and can't provide a constant DC voltage? Is there such a case? For those who think this is the case, I will provide some examples and research. DC electrified section (
An electric locomotive running on a conventional line (conventional line) transfers AC1 to the dining kitchen car.
If 00V must be transmitted, DC1500V
varies considerably between the time of power running and the time of motor off, and is by no means constant. As for the driving machine, there is no other way than to use a DC motor (I say this because there is a way to use an engine or other power, but I will not discuss that method here.

The first method is to attach a speed governor to the DC motor. This was invented by 'l' when Edison improved the wind-up phonograph to a motor-powered one, in order to keep it at 80 revolutions per minute.If it was too slow, he turned on the motor switch and
It is a centrifugal force contact type that switches off the motor if the speed is too high, and is still used in DC motors of 8mm cameras.

The disadvantage of this speed governor is that it has a short lifespan, and even high-end products that use palladium for the contacts do not last that long, making them not very practical in the world of high-power electricity.

As a result, frequency fluctuations occur in the DC motor V for reverse current transformation in the electric locomotive, but in practical terms this is not a big problem, and the dining car can continue to run smoothly.

If it is not a dining car but a measurement car, and the strict 50Hz
What would you do if you had to transmit electricity? This is the most interesting case, and there are many technologies that can meet this demand, but for example, if you create an alternating current with a precise frequency based on crystal light oscillation, and then use it to drive a synchronous motor to drive the quartz hour hand. It is possible to obtain an output AC with a precise frequency for the pot.

If one of these units is used as a converter and the other as an inverter, it can be used as a frequency conversion device. The drive machine in this case is of course a synchronous motor. The converter is directly connected to the shaft, and the inverter is connected via the transmission. Similar to a four-speed automobile transmission, you can shift the lever to, for example, 40.50.60.70.
You can freely create Hz, etc., and if you use a continuously variable transmission, you can freely create it in IHz increments. However, -
To add, both converters and inverters,
It is important to let the machine rotate at a constant speed before inputting information, so the procedure is to turn off the input, stop the machine, change gears, rotate the machine, and then input again. (If the input is applied at the beginning and end of the drive, the converter will output raw AC, and the inverter will output the alternating current in its raw state.)
(extremely low Hz alternating current comes out).

The relationship between the commi-cheater and the brush on this machine is very different from that on a general motor or dynamo. In other words, with a membrane-like multi-pole commutator, there is no problem even if adjacent pole pieces come into contact with the brush at the same time, but with this machine, if such a thing were to happen, it would be a serious problem. That's true. That is, the input will be shorted (both converter and inverter). Therefore, the insulating pieces (insulating zone between the pole pieces) of the commutator of this machine are set large.
On the other hand, the brushes are made of carbon that is horizontally long in the axial direction and as short as possible vertically.

Speaking of commutator brushes, there is usually one on the right.
It is decided that there will be one commutator on the left, but in the case of this machine, the commutator is long and slender, and multiple commutators can be installed, for example, four on the right horizontal row and four on the left horizontal row. It's okay to let them do that.

If the insulating piece is made large, for example in the case of converting, there will be a problem that the pole piece will not be able to give the brush all the way from the base of the alternating current wave to the base. One way to solve this problem is to dramatically increase the size of the commutator to about the same size as the armature. In this case, even though the absolute arc length of the insulating piece is the same, the central angle becomes smaller, making it possible to pick up alternating current waves all the way to the foot of the mountain.

This machine has such a structure, so when it is stopped, it is neither a converter nor an inverter, but just a direct-through device, so to speak, two wires (the brushes are in contact with the pole pieces). (when in a stopped state). Alternatively, the four terminals (brushes) are nothing more than isolated, insulated insulating blocks, so to speak, mere stones (when the brushes are in the stopped state, in contact with the insulating pieces).

What has been described so far is an explanation of the standard model of this machine, but since there is also a control model of this machine, we will explain about it below (in the case of conversion). (explain and explain).

1. Phase control type machine As mentioned before, the sine wave of the input AC is placed on the pole piece of the commutator of the standard type machine. Of the entire 360° circumference of the commutator, if the insulating piece of the brush holder is 200° on the left. If it occupies 20° on the right, the first pole piece above will occupy 160°. If the first pole piece occupies 1800 degrees, it will ride the entire peak of the sine wave from 0 to π, but the first pole piece at 160° will have the sine wave from 0+10° to π-10°. This means that the sine waves that have been cut off from the left and right foot are riding on it.

If we change the current structure in which the entire 160° of the first pole piece is made of metal and is continuous and integral (one pole piece metal plate), only 10° of both sides are made of metal and the central part 140° is made of metal. What would happen if we changed the structure of the first pole piece so that ° is an insulator? Sine wave 10°~20° and 160°~1
The 70° portion will ride on the first pole piece, and the 20° to 160° portion of the sine wave can be output as DC due to the insulator in the center part 1400 of the first pole piece. It doesn't show up.

Also, if 20° on both sides of the first pole piece are metal, and 120° in the center
If is an insulator, the sine wave has a width of 1200 at the center,
It gets cut.

To summarize this, the center cut of the first pole piece is the center cut of the sine wave.

At a power station like this, if, for example, six control mini cheaters with varying cutting rates (center cut angles) are placed side by side on the axis, the direct current will be voltage changes. In the previous example, the lowest voltage was produced by a compact cheetah with a center cut of 140°, and the highest voltage was produced by a center cut of 0°.
``Conmini Cheetah'', i.e. a standard model ``Conmini Cheetah''
(Standard Conmini Cheetah).

I mentioned earlier that I would take the plunge and make the Commie Cheetah the size of an armature, but if I did that, I would be able to easily control the DC voltage in 12 steps, 24 steps, and 36 steps instead of 6 steps. I will do my best to do it.

−. , f9. In contrast to cutting the center part of the first pole piece of a power control type machine with an insulator,
If both sides of the first pole piece are cut with insulators, DC power can still be controlled. The weakest output is
Only the center part of the first pole piece is thin and metal, so it is a small cheater that cuts off only the central part of the peak of the sine wave and pulls it out, and gradually expands the pole piece to the left and right. In the end, we arrive at the standard compact cheetah.

Therefore, the choppa I'm talking about here means cutting off (cutting away) the left and right foot of the mountain (cutting away and controlling the strong over the weak). .

In chopper control, the instantaneous maximum voltage of the output DC is always equal to the maximum voltage of the input AC. In contrast, in phase control, the instantaneous maximum voltage of the output DC is always less than the maximum voltage of the input AC.

3. Change the first pole piece of the chopping control type machine to pole piece, insulation piece, pole piece, insulation piece...
If you modify it like this, you can cut out a sine wave like a striped horse.

If the cut-off integral area and the cut-off integral area are equal, it is equal to the ratio of the electric wire (arch wire length) to the insulation piece width (when the brush length is infinitesimal).

4. There are various other methods for arranging the pole pieces on the mini-cheetah in addition to the three methods mentioned above, but I will omit their description.

It is desirable to have a built-in control mechanism. Conventional lines controlled DCl and 5KV with resistors, but the Shinkansen took a revolutionary step forward by switching to a system that controlled AC 25KV with a transformer (24 taps on the secondary side). At the time of its opening, there was still no intelligent converter in the world that incorporated a control mechanism like a thyristor, so it could be said that it was an extremely advanced Shinkansen technology compared to single-function, single-cell silicon rectifiers.

However, with the advent of thyristors and the ability to perform chopper control and phase control, the most advanced trains were those that used them to eliminate resistors and transformers. However, it is still in the practical testing stage. There is no way that conventional lines and all private railways will just jump into this system. If we could have a converter that is resistant to heat, a large capacity converter that generates strong electricity, a converter whose efficiency is comparable to that of a thyristor, and whose built-in control mechanism is comparable to that of a thyristor, this dream converter that has been a dream come true for many years in the electrical engineering world. Railway modernization can be promoted all at once, including AC electrification, lighter and faster rolling stock, and more efficient use of electrical energy.

This thyristor-type rotary current transformer is based on the rotary current transformer (physical strength type) with a glorious history that once ruled the world of high-power electricity.
It was born to a thyristor (brainiac) who is currently attracting a lot of attention in the world of light electrical appliances. As a result, first of all, it is suitable for high voltage and large capacity, can withstand overload, can withstand heavy use in hot places, and has no failures.

This is because he received his mother's gift, and his performance is superior to that of his father.

Second, it is extremely efficient, small and lightweight.

This is because she inherited her father's blood, and her mother's ability is also excellent.

Third, the price is the lowest. This is a completely new property created by the synergy of parents and mothers, and it is a property that is superior to fathers, superior to mothers, and superior to mercury rectifiers and silicon rectifiers.

The above are the effects of this invention.

Claims (1)

[Claims] 1. A current transformer that rotates a commutator and slip ring using a drive machine, and performs rectification and reverse transformation using the principle of a high-speed synchronous switch.