Tutorial on creating Tesla coils

Today is Nikola Tesla's 153 birthday. I specially organized and published this tutorial on creating Tesla coils. Let's worship this "God's spokesperson ".

Friends who have played the red alert must have a profound image of the magnetic storm coil. Let's create a "magnetic storm coil" today.

Let's take a look at the masterpiece of Tesla coil fans:

The above picture fully demonstrates the charm of Tesla coil's "artificial lightning", which is a magical magic that attracts many people to pursue this beautiful spark, feeling the initial shock to the fire.

Preparations and precautions before making Tesla coils:
The whole production is designed based on a medium-sized Tesla coil with a transformer power of W. (Discharge distance:> = 120) (Note: The discharge distance of the Tesla coil is proportional to the power)
Main materials and approximate costs:
1: high voltage transformer 1000 W input 220 V output 10 kV
2: a large number of non-polar capacitors, such as 0.047 UF 1000v ~ (1600 V-) the CBB capacitor needs to be prepared with about 100 Cus. Please convert the high-voltage capacitor with large capacity by yourself
3: 13 cm in diameter, 1 m length of poly (vinyl chloride) pipe (wall thickness 0.6-1 cm), PVC pipe will also be, 0.8 cm thick insulation sheet (cannot be wood! Best plastic) about 2.5 square meters, 0.5 cm thick insulation sheet (non-wood !) About 1.5 square meters, all of which can be bought in the home decoration City (that is, those who buy paint, plates, tools, etc.)
4: wire, multi-core copper wire, 1000v50a about 6 meters; 10kv1a wire 3 meters
5: Pressure-resistant enamelled wire diameter 0.5mm 900 m long
6: 0.8 cm in diameter copper tube (wall thickness more than 1mm) 8 m long, 3 cm in diameter thick> 1mm in length 1 m copper tube can be bought in auto parts or hardware and other places
7: electric hand drill, screwdrivers, hand saw, pliers and other tools, common screws, plastic screws, epoxy resin glue, Steel Ruler, etc.
8: used for gas water heater exhaust pipe (metal production, bending, diameter more than 10 cm) produced after calculation to obtain the length.

Tesla coil assembly and circuit diagram

Although the design follows this article as a "standard" Tesla coil, the producer does not have to spend a lot of energy and time on its principles and computing, but out of respect for Tesla and convenience for makers to make Tesla coils of other specifications, we should give a general understanding of the principles and calculation methods here. also, creating a Tesla coil will improve your hands-on capabilities and electrical knowledge.

Circuit sketch

Calculation Formulas involving Tesla coils

1. Arc Length: arc length L (in inches), transformer power P (in Watt), L = 1.7 * SQRT (p) (SQRT is open)
2. Capacitor array capacity: transformer output voltage (AC) E (Unit volt); transformer output current I (Unit milliampere); capacitor array maximum capacity C (Unit Micromethod ); AC frequency f (unit: Hz) C = (10 ^ 6)/(6.2832 * (E/I) * f) [The capacitance size involves a matching problem with the transformer power, when the capacitance is too high, when the AC rises to the top point (that is, SQRT (2) * V, the capacitor voltage is too low to break through the air gap of the firearms, then the firearms cannot start and cannot work, the entire system cannot be started]
3. The calculation of the capacitor array is a simple string of the capacitor, which is connected in parallel and learned in junior high school. for example, when the power of the transformer is 1000 Watt, the output voltage is 10000 V (AC), the capacitance matching is 0.0318 UF, and the current capacity is 0.047 UF 1000 ~, 1600-, and a little more insurance to withstand the pressure of V ~ The capacitor array is arranged as follows: 15 capacitors are connected in series to form a basic chain (BC), and 10 other basic chains are connected in parallel (j). A total of 150 capacitors are required, if the partial pressure of each capacitor is reduced to 630v ~ (This can greatly extend the capacitor life), then: 24-bc, 16-j, a total of 384 capacitors are required.
4. Others: shock frequency: F = 1/(2 * pI * SQRT (L * C ))

Calculation of the main coil is as follows:

Calculation of the subpole coil is as follows:

Calculation of discharge terminals is as follows:

Component preparation

Main coil section of Tesla coil

In the design of the Tesla coil, the main coil uses copper tubes to make mosquito coils. copper Tube is used for automobile, heating, central air conditioning in the tube wall thick pressure copper tube. 8mm in diameter around 9-10 turns (about 9 meters required)
For example, a copper tube (which should be smooth and rust-free as much as possible ):

Copper Tube into such:

In this way, the primary coil can be applied to the secondary pole coils of 6 inch to 8 inch (the disk copper tube is time-consuming and hard-working, but it should not be as fast as possible .), 5mm thick soft plastic board (non-brittle plastic) is also needed as the main coil bracket, and it will be shot at an equal distance (to make it 9mm eye, do not wear it) choose ordinary medium density board for the Base, this base is still used, and other things will be placed in the future. also try to process well, then put the copper tube and plastic bracket wear.
Main coil Bracket

Copper Tube and plastic bracket wear:

The inner ring joint section. The middle density bottom section opens a joint in the corresponding area.

Find another copper tube for grounding insurance. Note that it cannot be closed! Installation:

Fabrication of capacitor Arrays

In the Tesla coil, a good capacitor is very important. the core position of the capacitor is that the energy of all the ARCs is directly provided by the capacitor, which is obviously strange and reflects the genius of Tesla. High-Voltage capacitors are difficult to buy and are expensive. Therefore, a common practice is to connect and parallel common unpolar capacitors to achieve the required pressure and capacity.
Materials to be prepared:
1. non-polar capacitor, (polyethylene, polypropylene, CBB capacitor, etc.) common high voltage capacitor specifications are: 1600 V-0.047 UF, 1600 V-0.068uf; resistance 10 M Euro (000000ohm), a large number of such:

2. Organic Glass Plate
3. plastic screws

Steps:
1. first, calculate the number and arrangement of capacitors. Based on the previously mentioned transformer matching calculation, the current capacity is 0.0318 UF/10 kV, and the current capacity is 1600 V-0.047 UF. (Note: the voltage labels of the capacitor are DC, and the AC voltage of the capacitor is related to many factors such as the capacitor material. You cannot simply think that the AC voltage value is obtained by dividing the DC voltage value by 1.414 .), from the perspective of life and security, we recommend that you set the SLB value of each capacitor to listen V ~ The whole capacitor array is composed of 22 series of one chain, 14 chains in parallel, a total of 308 capacitor resistors, the purpose of resistance is to discharge the residual charge in the capacitor when it is stopped. The method of use is that each capacitor must be connected to a 10g resistor (1/4 ~ 1/2 million)
Security Tips: If no discharge resistance exists, the energy stored in the capacitor array may exist for a long time and cause personal injury!
A capacitive chain is displayed, which is arranged by the snake line:

Note! Do not close contact between capacitors! There must be a certain gap between the layer and the layer should be separated by 4mm thick organic glass, each layer contains two chains, fixed using plastic screws (usually called Nylon screws ), each layer has its own interface to make it an independent and usable unit,

Fabrication of sub-pole Coils
The secondary coil in the Tesla coil is the most time-consuming part of the Tesla coil. The following materials are required:
High-quality enamelled wire (must be purchased. At present, the quality of China's enamelled wire is generally low. As far as I know, only one company has obtained international certification). The diameter of the wire varies from the following:
51mm mm 0.57mm
2. poly (vinyl chloride) pipe with a diameter of 15 cm and a minimum of 2 meters. The thickness is good. (generally, it is about 4-8mm thick)
3. use wood to create a record frame. we also need to make two circles to wear on both sides of the cylinder, then eye-hitting in the middle of the disc, and penetrate into the central axis. It can be wound in the line shelf. A circle, around 900 ~ 1000 turns is suitable for the system. the entire winding process is about 7-8 hours. Therefore, you must fix the items that have been completed during the rest period, so that you do not have to discard all your efforts. when winding, be sure not to knot the wire, do not use two wires to connect, the market is not long enough to find the length of the paint wire, (about 500 m ), however, the whole volume seems to be expensive, so it depends on the producer's choice. It is best to have a friend to help.
Legend:
Poly (Vinyl chloride) Pipe:

High-quality enamelled wire:

Fixed disc of the bucket:

Secondary pole coils on the relay:

Sub-pole coil joint (ground ):

Secondary pole coil joint (discharge terminal ):

Preparation of firearms
The following materials are required for fire fighting:
200mm diameter PVC pipe, 400 long
90mm long, 20mm copper tube in diameter
3. Several double-head screws (double the number of copper tubes)

In fact, it is equivalent to a toggle. The energy is transferred from the transformer to the capacitor array when the capacitor array is fully charged. When the voltage between the two poles reaches the voltage that breaks through the gap in the fire, the lighter is fired, at this time, the capacitor array forms a loop with the main coil, completing the L/C oscillation and then passing the energy to the sub-pole coil.

Procedure:
1. Shoot the copper pipe first.

2. After eye drilling on the PVC pipe, the copper tube is fixed inside the PVC pipe (the gap between each copper tube and the copper tube is approximately controlled at 1mm ),

3. assembled

In order to adjust the discharge gap as needed, each phase of the bolt represents a discharge gap of 1mm (the bolt is the terminal) in this way, you only need to change the wiring bar to easily adjust the voltage according to your design.
Note: When the firearms work, a large amount of heat will be generated, and often concentrated in a small area, so the heat dissipation equipment must be very powerful! General use of small vertical fan (that blow wedding arch): generally in a few hundred watts, sufficient air volume. you only need to pay attention to adding a simple air filtration device to the air inlet to prevent heavy dust. generally, no fan is used for heat dissipation. After the Tesla coil is working for dozens of seconds, it may lead to high temperature deformation of the firearms. After the fan is added, the working time of the entire Tesla coil can be extended to 10 minutes. in addition, it is often used to clean up the fire and remove Electroslag and dust.

Production of discharge Terminal

This part of production is relatively simple and casual. Here I will introduce a more mature and simple production method, that is, the most common coil discharge terminal (because it corresponds to my program and makes computing easier)]
Main materials:
1. 4-inch diameter gas water heater ventilation duct, (it is the kind of all-metal bend, the home has a gas water heater to see it)

2. 7-inch diameter flat metal disk (used for dispatching), other similar metal objects can also be, key 1. Flat Bottom 2. Metal

3. thick aluminum foil wrapped in gold coins and chocolate
First, the bottom of the flat metal disc is fixed with screws, and then the aluminum tube disc is circled so that it can be properly stuck on the skeleton of the flat metal disc. The interface of the aluminum tube is sealed with aluminum foil, the wiring points are located in the frame center of a flat metal disk, and the finished product is assembled. So far, all the important parts of the Tesla coil have been completed.

Some additional instructions on Tesla coils
There are still many things to note about the production of Tesla coils, including:
1: the skeleton of the secondary pole coil is required for the Rao part of the polyethylene drum. Generally, the diameter of the Rao line and the length of the bucket of the Rao line are about.
2: The base version of the main coil can be made with some slightly cheaper materials, because the requirements for it are not high, of course, it is best to make all the plastic sheet can be made with acrylic sheet, this is strong and beautiful.
3: There are actually many methods to create a firearms. The key thing to note is. discharge parts require fast thermal conductivity B. discharge part thickness should be sufficient C because of the highest replacement frequency of the firearms, so the design should be easy to replace, the price is low.
4: for high-voltage capacitors, I saw a high-voltage capacitor in the microwave oven the other day with a capacity of 2100ac 1 UF and an internal Integrated Discharge resistor. It seems that this capacitor is also a good solution.
5: It is generally difficult to purchase the main transformer. You can go to the local electronic market to ask if it can be customized. If not, you can buy a neon power supply, the specification is 15000 v ac 50Hz 60mA. It looks like a box. It is widely used in foreign Tesla coil fans. In addition, it is used in two series for the Japanese second-hand 110 vacin-6300 vacout transformer.

Via