Most modern household appliances made using inductive elements are easily adjustable for power consumption. True, this is true only for those cases when they already provide such an opportunity. However, even in its absence, you can modify the device with your own hands, by incorporating a triac voltage regulator in the inductive load into it.
Advantages and disadvantages
There are voltage regulators on the market, built on the basis of modern BT136 600E triacs, which in their performance characteristics significantly exceed thyristor analogs. The use of bidirectional control semiconductors allows to achieve the following advantages:
- reduction of nonlinear distortion;
- improving the regulatory characteristics of the entire circuit;
- small savings on energy consumption.
The main advantage of any electronic controllers is the absence of mechanical contacts that quickly fail and create a lot of noise.
The not very significant disadvantages of these devices include:
- increased sensitivity to transients in control circuits;
- the need to install a radiator to remove heat;
- limited frequency range.
Despite all these disadvantages, stabilizers on triacs are successfully used to adjust power in an inductive load.
Principle of work and purpose of application
The principle of operation of the triac controller is based on the features of semiconductor devices that limit the amplitude of the alternating current with a simultaneous decrease in power in the load. At a given frequency of the mains voltage, this indicator can be regulated within small limits (no more than 20-30%).
The quality and depth of adjustment depend on the control circuit of the triac elements, which involves various designs.
In the simplest cases, it consists of several discrete elements: diodes, an isolation transformer, resistors and capacitors. In more complex devices, the function of the regulatory module is performed by a microchip or microprocessor. In accordance with the control method of the triacs, various methods of changing the amount of power given to the load are possible. The most common method that allows you to effectively, with minimal loss, is to influence the phase of the converted voltage. In accordance with the variable parameter, this method is called pulse-phase, and the device operating on its basis is a phase power regulator.
Triac circuits are used in many devices, when working with which you have to deal with inductive load - the motor windings, in particular. This category of industrial and household appliances includes:
- washing machines, hair dryers, as well as compressor units;
- boilers, vacuum cleaners and a number of lighting models;
- pumps and induction motors of factory machines;
- boiler equipment and even ordinary soldering irons.
The nature of the use of equipment controlled by phase power controllers on triacs is almost the same. Only operational indicators of the semiconductor devices themselves differ: the magnitude of the current, power in the load, control efficiency, efficiency and others.
Do it yourself
Anyone who has mastered the principle of his work can make a voltage regulator on triacs with his own hands.To do this, you must first select the option of a proprietary device suitable for manual copying. One of the conditions for making the right choice is to make your favorite circuit simple enough to repeat.
Circuit options
Among the popular models of industrial devices that can be taken as a sample, the following stand out:
- Products built on the basis of devices of the brand BT136 600E, the voltage regulation switching circuit of which is provided on the Internet.
- Devices on triacs BTA16-600, having a more complex organization of switching.
A feature of the first circuit solution is the use of only one triac. By means of such a controller, repeated in the form of homemade work, it is possible to control the operating modes of a household soldering iron with a power of up to 0.09 kW. In addition, if you have a device, you can adjust the brightness of the glow of a table lamp or the rotation speed of an electric fan.
Among the circuit solutions used for the independent manufacture of the regulator, the product based on the relatively powerful BTA16-600 semiconductor devices stands out. Its characteristic feature is the presence of a neon bulb included in the output circuit. The brightness of its glow indicates the amount of power given to the load at the moment, which is very convenient for working with many consumers.
A user who does not have experience with microchips will have to use the combined option. The control unit is taken from a simpler product based on BT136-600E, and the control circuit with a neon lamp is used at the output. In a situation where the regulator is designed to control the illuminator with its own internal starting element (starter), it is allowed not to set the neonka.
Another variant of the proprietary repeating device is possible, which uses MAC 97A6 controls. This switching circuit is suitable for 220V lamps.
Self assembly
The structure of a typical controller circuit on triac includes the following required nodes and elements:
- rectifier diodes (or bridge);
- an adjustment resistor, the handle of which is displayed on the front panel of the home-made device;
- any type of limiting dinistor;
- triac BTA16-000;
- indicator LED instead of neonka;
- fuse.
After all these details are soldered into the circuit, you will need to check the operation of each of the individual modules. To do this, go through the entire chain from the entrance to the load.
The alternating voltage 220 V rectified by the diodes through the adjustment resistor is first supplied to the limiting element, and then to the control electrode BTA16-000. Depending on the position of the potentiometer knob, the triac will open more or less, changing the amount of power given to the load. According to this description, the assembled circuit is checked for the correctness of its assembly and operation.
By means of such a simple regulator, it is possible to smoothly change the output power of a soldering iron or a table lamp, for example.
Regulator setting
After completing the solder work and all the necessary connections, you can proceed to check the homemade product for operability. If deviations from the normal modes specified by the description of the circuit solution are detected, the device settings will be required. It consists in checking each of the elements for current and voltage. For this, it is most convenient to stock up on a special device - a multimeter, and even better - an electronic oscilloscope.
Before setting up, it is important to remember that the triac in this circuit performs the function of a phase regulator.Its main purpose is to switch the circuit at the time of the transition of the half-wave voltage of the zero point, taking into account the magnitude of the current load.
In the initial state, the triac is closed, since the voltage at its control electrode has not reached the desired value. As the capacitor charges, through a chain opened by the arrival of a half-wave of voltage, the potential on it and on the dynistor connected in parallel gradually increases.
These processes are clearly visible on the screen of the oscilloscope, in the presence of which the instrument setup will be significantly simplified.
When the voltage at this point reaches approximately 30 volts, the dinistor and triac simultaneously open for a time equal to the half-wave period. Due to the switching of the control chain periodically repeated at a frequency of 50 Hz, it is possible to change the amount of power in the load within specified limits.
If you have experience working with a soldering iron and electronic devices, it is possible to assemble and configure the control device without much difficulty. The main thing is attentiveness and strict adherence to the instructions given.
