Harmonic and Flicker Reduction Method Based on Mains Voltage Control via PWM in Heaters and Instantaneous Water Heaters

Abstract

The invention relates to a method for controlling the power applied to a heating element in electric heaters and instantaneous water heaters. Within the scope of this invention, alternating voltage from the electrical grid is used directly or rectified, and power operating on the principle of pulse width modulation is applied to the heating element via semiconductor elements. In this method, the average power value is adjusted by dividing the voltage waveform in the time axis with high-frequency switching without interruption, thus achieving the desired temperature control. This approach maintains the continuity of the current drawn from the grid, reduces harmonic components, and minimizes the effects of voltage fluctuations. The invention offers a solution that provides precise and stable power control while meeting electromagnetic compatibility requirements.

Description

1 TARIFF Controlling Mains Voltage in Heaters and Instantaneous Water Heaters Using PWM Harmonic and Flicker Reduction Method Based on Technical Area The invention relates to devices that generate heat using electrical energy; especially instantaneous water heaters, room heaters (IR heaters, resistance heaters, wall-mounted heaters) power control used in devices such as (mounted, freestanding or portable heaters) It falls within the field of systems. More specifically, the invention relates to the devices in question. with electronic control circuits for temperature and power adjustment within the scope of electromagnetic compatibility (EMC) criteria of circuits It includes technical solutions related to its evaluation. The invention applies the mains voltage by full-wave rectification or direct application. In this way, using PWM (Pulse Width Modulation) technique and power supplies such as IGBT, CMOS 15 a power control system based on driving a heating resistor using semiconductors It relates to the method. This method allows for classical phase angle control or alternation control. Harmonic distortions and flicker effects occurring in shear-based systems. EMC emissions are significantly reduced, devices are made to pass EMC tests, and At the same time, more precise and stable temperature control is achieved. 20 State of the art Electric heaters and instantaneous water heaters use resistance as a heating element. These are devices that generate heat through the passage of current. The 25 obtained in these devices... The temperature value is controlled by controlling the electrical power passing through the resistance. It is being adjusted. In order to provide power control, the alternating current taken from the grid is used. The current needs to be regulated using specific methods. The methods used for this purpose... circuits consist of electronic semiconductor elements and control alternating current. These are power electronics circuits capable of handling alternating current (AC) chopper circuits, generally known as 30. It is called [name of name]. 2 Alternating current chopper circuits use alternating current switches with constant amplitude and frequency at their inputs. By processing the mains voltage, an adjustable voltage with an effective value is obtained at the output. This voltage is applied to the heating element to control the power. And thus the temperature is adjusted. However, this control process only works with power setting 5. not only providing, but also compatible with the network, stable and It must be carried out in accordance with standards. Electromagnetic technology is required for the production and marketing of electric heating devices. It is mandatory to pass compatibility and low voltage tests. Electromagnetic 10 compatibility means that a device does not emit disruptive effects to the network during its operation, and This means it does not negatively affect the operation of other devices. In this context, harmonic and flicker tests are of particular importance. Harmonics are the result of the deviation of the current drawn from the grid from the ideal sinusoidal form. This refers to the resulting distortions. These distortions are unwanted frequencies in the network. This leads to the formation of harmonics, which reduces energy quality. The increase leads to additional heating in transmission lines, increased losses, and an increase in the power factor. this can cause the power to drop and deteriorate the performance of other electrical devices. Flicker explains the sudden and intermittent power draw of loads connected to the electrical grid. resulting voltage fluctuations, especially in lighting a phenomenon that arises from creating a time-dependent change in luminous flux in their systems It is an effect. This effect refers to light vibrations that can be perceived by the human eye. This is the reason why, within the scope of electromagnetic compatibility standards This is a type of disruption that needs to be limited. This situation reduces user comfort by 25%. This has a negative impact and causes instability in the electricity grid. While current technologies allow for power control of heating devices, It is often possible to perform this control in a way that is compatible with the network. This is not the case. Especially in devices operating at intermediate power levels, the control used is 30 Due to the nature of these methods, the current drawn from the grid is discontinuous, unbalanced, and 3 It appears to have a distorted structure. This situation directly affects harmonics and... This causes flicker generation and affects the electromagnetic compatibility of devices. This leads to them failing the tests. In other words, current systems are capable of performing the heating function, but 5 It achieves this by degrading network quality. Today, energy quality and... The increasingly stringent electromagnetic compatibility criteria mean that not only heat It is not enough to just produce it; this process must also be carried out without damaging the grid. This necessitates its implementation. Therefore, the techniques used in current practices... While the methods are functional, they are inadequate in terms of compliance with standards. 10 It remains. The main methods used in current techniques within this scope are detailed below. It has been explained as follows: 1. Half-Wave Power Control Method In this method, only one alternation of the mains voltage is supplied to the heating resistor. One alternative is being implemented, while the other is being prevented through electronic circuits. A period of alternating current consists of two equal parts: positive and negative. It is formed. In this method, the load is applied as a result of cutting one of these parts. The energy used is being reduced. However, as a result of this process, the current waveform loses its symmetry and becomes direct current. This component is formed. This situation creates imbalance in the network and especially 25 A noticeable flicker effect occurs at low power levels. Furthermore, the load... Receiving power only in half-periods makes the power drawn from the grid irregular. This is what causes it to come. The most significant disadvantage of this method is the limited power control and the fact that the current is naturally 30 It is a serious deterioration of its structure. Therefore, devices that operate using this method, 4 It particularly fails flicker tests and modern electromagnetic... It fails to meet compliance requirements. 2. Alternating Current Chopping Method with Phase Angle Control In this method, the zero crossing point of the grid voltage is determined, and from this point... Power elements are switched on after a certain delay. The delay time is called the phase angle, and the load is adjusted by changing the phase angle. The power transmitted to it is being adjusted. In this method, semiconductor elements such as triacs and thyristors are used to analyze voltage waves. This causes only a specific part of the form to be applied to the load. This situation leads to the interruption and distortion of the sinusoidal waveform. It opens. This type of waveform cutting results in high levels of harmonics. Components are forming and the current drawn from the grid becomes irregular. Harmonics affect not only the device itself, but also other devices connected to the same network. This has a negative impact. Furthermore, the amount of energy the load draws from the grid depends on the phase angle. The power changes suddenly, which increases the flicker effect. 20 Although theoretically a wide range of power control can be achieved with this method, The control achieved in practice is not stable. Errors in zero-crossing detection, due to switching delays and phase angle fluctuations of the system performance is declining. For these reasons, this method is suitable for both harmonics and flicker. 25 It falls short in terms of testing. 3. Alternation Skipping (Period Skipping) Method In this method, the mains voltage is transferred entirely to the load for specific periods. It is applied, and some periods are completely interrupted. This process is usually zero. This is done by synchronizing it according to the checkpoints. The basic working principle of this method is to control the average power of the load by setting a specific 5 It involves being fully activated and fully deactivated at intervals. However... This situation causes the power drawn from the grid to increase and decrease suddenly. These sudden changes cause voltage fluctuations in the grid, resulting in high... This causes flickering at certain levels, especially at low power levels. This effect is becoming more pronounced, requiring devices to pass flicker tests. It makes things more difficult. Furthermore, since power control is intermittent in this method, precise temperature control is possible. It is not possible. The intermittent, rather than continuous, operation of the load affects both energy quality and performance. It both damages and negatively affects device performance. All the methods described above enable power control in heating devices. Together, this control is compatible with the network and compliant with standards. It is unable to do so. The common feature of these methods is that the current drawn from the grid is 20 Their goal is to deviate from the sinusoidal form and make it irregular. This situation leads to an increase in harmonic components on the one hand, and flicker on the other. This leads to the emergence of its effect. Consequently, those working with these methods The devices fail electromagnetic compatibility tests or exceed limit 25. It operates within these values. Standards for electrical appliances are becoming increasingly strict today. Its arrival has made it imperative to maintain energy quality. Now, it's not just about heat. It is not enough to produce it; this process must be carried out in a stable and controlled manner without damaging the network. 30 It needs to be done in some way. 6 Therefore, harmonics caused by the methods used in current techniques and It eliminates flicker problems, works more seamlessly with the network, and... a new electronic application method that can provide precise power control over time It is needed. 5 Our invention eliminates the harmonic and flicker issues encountered in the existing techniques described above. An electronic power controller developed to solve problems caused by... It relates to the method. Our invention allows us to either directly take alternating voltage from the electrical grid or directly... after being used or subjected to full-wave rectification, the pulse a system that operates using width modulation technology and includes power switching elements This involves passing alternating current through a control circuit and applying it to the heating element. In this way, the current passing through the heater, and consequently the heat value obtained, is controlled and 15 It can be adjusted in a stable manner. The pulse width modulation used here is a voltage with a constant amplitude. the average of the signal by changing the transmission time within a specific period It is a control method that allows the power value to be adjusted. In this method, the signal is 20 It is switched on and off within a specific time interval, and is open. Power transferred to the load by changing the ratio of dwell time to closure time. is being controlled. The modulation signal in question is controlled by analog or digital control. It can be produced through its units. The power switching elements used in this invention are high-speed semiconductor elements capable of switching, and through these elements The voltage applied to the resistor is switched on and off in a controlled manner to obtain the desired power value. is obtained. Thanks to this structure, waves are obtained as in classical methods. Instead of cutting off specific parts of the form, the tension is controlled and high 30 Frequency switching is enabled. 7 The invention has two different application methods: In the first application, the alternating voltage taken from the grid is rectified using full wave rectifier. It is subjected to this process and the resulting rectified voltage has a pulse width of 5. through power elements that switch via modulation, to the heating resistor This application is implemented. In this application, the voltage applied to the resistor is rectified and It has a modular structure. In the second application, the alternating voltage taken from the grid is rectified using any 10 rectifier. Control via direct pulse width modulation without undergoing any processing. is transmitted and the power is transferred to the heating resistor via switching elements. This is implemented. In this case, the voltage signal retains its alternating nature, however Modulation allows for adjustment of the average power value. In both applications, the basic principle is that the voltage and current applied to the resistor... it should be as regular as possible and have a character close to a sine wave shape. The aim is to ensure that sudden changes and irregularities in the current drawn from the grid are avoided. The formation of harmonic components is significantly reduced. In the methods used in current techniques, power control is generally based on voltage waveforms. by cutting off or completely blocking certain parts of the form These methods provide zero-crossing point detection and phase delay. such as creating or completely disabling certain alternatives The following processes are used. 25 In these types of methods, the voltage and current waveforms are distorted, and the load is disconnected from the grid. It draws power in an irregular and intermittent manner. This leads to harmonic generation and It directly causes the flicker effect. 8 In contrast to these methods, our invention does not interrupt the voltage waveform; instead, power regulation with high frequency and controlled switching. This is done in such a way that the current drawn from the grid becomes more regular, and The waveform becomes closer to a sinusoidal structure. The invention also includes features such as zero crossing point detection and phase angle control. Complex and error-prone processes are not needed. This is how the system works. This ensures more stable, simpler, and more reliable operation. The invention involves the following method: 10 - The waveform of the current drawn from the grid is being made more regular, and Harmonic components are significantly reduced. - The power change is controlled and continuous, not sudden and intermittent. Since this is done, the flicker effect is largely eliminated. 15 - Performed within the scope of electromagnetic compatibility of devices. It is ensured that it passes harmonic and flicker tests. - Because power control can be done precisely, the temperature setting is more stable and... It is being carried out correctly. - Numerous intermediate stages can be created across a wide power range, and 20 This offers the user more flexible control options. - The system operates more stably and the energy quality is better compared to existing methods. It is protected. Brief description and technical advantages of the invention 25 The invention relates to heating elements in electric heaters and instantaneous water heaters. It is a method for controlling the applied power; the grid voltage direct or full wave rectified, with pulse width modulation The operating power is controlled via switching elements and the resistance is 30 It includes its implementation. 9 In this invention, the mains voltage is taken as a constant amplitude input signal. and this signal, with transmission and cutoff times varied at a specific switching frequency It is controlled by a pulse width modulation signal. This control process, 5 through semiconductor power elements capable of high-speed switching is being carried out, and the average power value applied to the resistance is in question. It is adjusted by changing the modulation rate. The fundamental technical feature of the invention is that the voltage and current applied to the resistor are not classical. as in methods involving the breakdown of the waveform or alternations of 10 not by cutting, but by high-frequency and controlled switching This is a regulation that preserves the waveform of the current drawn from the grid and A character close to a sinusoidal structure is obtained. Thanks to this technical approach; 15 - Power control without distorting the waveform of the current drawn from the grid. is being provided, - The formation of harmonic components is reduced, - By preventing sudden load changes on the grid, voltage fluctuations are reduced to 20. is being minimized, - Harmonic and vibration testing within the scope of electromagnetic compatibility. It becomes possible to meet the criteria, - Temperature can be controlled continuously and precisely because power control is possible. The setting is stabilizing, 25 - Stepless or multi-stage power adjustment is possible. The invention adapts phase-delay switching and alternation interruption techniques used in current technologies. or unlike period-skipping based methods, it is grid-compatible, continuous and By providing controlled power transfer, it meets electromagnetic compatibility requirements 30 It offers a solution that meets the needs. Detailed description of the invention The invention relates to power used in electric heaters and instantaneous water heaters. This relates to the control method and the pulse width modulation of the mains voltage. 5 an electronic device that controls the application of heat to the heating element using this technique. It includes the application method. Description of the Basic Components Used The power switching elements used in this invention are designed for high-speed switching. They are semiconductor elements that can perform switching operations. These elements are electrical. It enables the controlled transfer of energy to the load. IGBT (Insulated Gate Bipolar Transistor): High voltage and high current. 15 used in applications, controllable with low power at the input and output. It is a semiconductor element capable of high-power switching. This element is a It can act like a switch, quickly turning the electrical current on and off. CMOS-based power transistors: Operate with low driving power requirements and These are semiconductor elements capable of fast switching. These elements have a high 20 By enabling frequency switching, precise power control is possible. It enables its realization. PWM (Pulse Width Modulation): A signal that is open within a fixed period. a control based on changing the occupancy period and the closure period This is the method. In this method, the voltage is not constantly changed; instead, the voltage is adjusted to be 25%. The duration for which the load will be applied is checked. As the open time increases, the average As power increases, average power decreases as it decreases. PRINCIPLE OF IMPLEMENTING THE INVENTION The basic principle of the invention is that the energy applied to the heating element is continuous and uniform. not in that way, but by dividing it into small time intervals with very rapid switching 11 by providing this information and changing the ratio of these time periods, the average power It is the adjustment. A resistor is physically a heat-generating element whose heat output is equal to the square of the current passing through it. It generates heat proportionally to the current applied to the resistor. Therefore, the current applied to the resistor must be 5 By controlling the average value, the amount of heat obtained can also be controlled. 1. APPLICATION METHOD (APPLICATION WITH RECTIFIED VOLTAGE) Rectified voltage is a unidirectional voltage obtained by applying a rectification process to alternating voltage. It is a form that has been modified to allow current flow. Alternating voltage normally changes direction over time, meaning it can be positive or negative. It is a voltage that flows bidirectionally. Rectification converts this voltage to negative. The alternations are reversed to the positive direction, so that the current flows in only one direction. 15 It is arranged. In full-wave rectification, both the positive and negative halves of the alternating voltage are rectified. The periods are converted so that they are in the same direction. The result of this process is... The voltage is a type of voltage that does not change direction but has a fluctuating structure. 20 This type of voltage allows for more stable and controlled switching in power control circuits. It makes it possible to do so. In this application, the system works as follows: 1. The alternating current voltage from the grid is applied as the circuit input. 25 2. This voltage is passed through a full-wave rectifier circuit. As a result of this process... The negative and positive alternations are made to move in the same direction. 3. The resulting rectified voltage is applied to the power switching element. 4. A pulse based on the temperature value determined by the control circuit. A width modulation signal is generated. 30 12 5. This modulation signal switches the power transistor on and off at a very high frequency. 6. When the transistor is on, voltage is applied to the resistor; when it is off, voltage is applied to the resistor. It is cut. 7. By changing the ratio of on time to off time, the resistance can be adjusted. The average power transmitted is adjusted. 5 In this method, the voltage is not interrupted continuously, but rather very quickly and in a controlled manner. Because it is supplied in a switched manner, the current passing through the resistor is more even. It gains character. 2. APPLICATION METHOD (DIRECT ALTERNATING VOLTAGE WITH 10 APPLICATION) Direct alternating voltage, as received from the electrical grid, is any... This is the voltage used without undergoing rectification or conversion. This voltage has a sinusoidal waveform that changes direction over time and is positive. It consists of positive and negative alternations. Therefore, the current constantly changes direction. 15 In applications using direct alternating voltage, the voltage form is preserved and The power control process is performed on this sinusoidal structure. In this application, without any rectification, the system works as follows: 1. The alternating voltage from the mains is fed directly into the power control circuit. It is applied. 20 2. The power level corresponding to the desired temperature is determined. 3. A pulse width modulation signal suitable for this power level is generated. 4. The power transistor switches on and off according to this signal. 5. Alternating voltage is applied to the resistor at specific time intervals. It is interrupted at time intervals. 25 13 6. Thanks to this rapid switching, the average power value seen by the resistor is... It is adjustable. In this method, the alternative structure is preserved, but energy transfer is done via modulation. It is being checked. In the methods used in current techniques, the current waveform is interrupted or 5 Because it is breaking down, the current drawn from the grid becomes irregular. This This situation is due to the formation of high harmonic components and sudden power changes. It causes the flicker effect. In the invention: - The voltage waveform is not directly interrupted, 10 - Energy is delivered in a controlled manner by dividing it into small time intervals. - Because the switching frequency is high, the resistance can withstand these rapid changes. It perceives it as an average force. - Due to the thermal structure of the resistance, the rapid on / off effects are evenly distributed with heat. This is reflected in the following way, 15 - The current drawn from the grid is more consistent rather than fluctuating in sudden bursts. It is gaining structure. As a result of this physical condition: - The current waveform becomes closer to a sinusoidal form. - Harmonic components are significantly reduced, 20 - Since the grid is not subjected to sudden loads, voltage fluctuations do not occur. - The flicker effect disappears or falls below the threshold values. - The device passes electromagnetic compatibility tests. With current techniques: 25 14  The wave is interrupted by phase angle control.  Alternatives are prevented  Periods are skipped  Components such as triacs and thyristors are used. In these methods, the current is intermittent and irregular. 5 In the invention:  The wave is not interrupted, it is switched on in a controlled manner.  Power transistors are used  High-frequency modulation is applied.  The current is more continuous. 10 This difference is directly reflected in the quality of energy. The advantages gained through the invention are based on the following physical reasons: Harmonic reduction: Since the waveform is not cut off, the current remains close to a sinusoidal shape. Flicker reduction: Power is delivered gradually, not suddenly. 15 Precise temperature control: The modulation rate can be continuously adjusted. Stable operation: No need for zero-crossing detection. High efficiency: Energy losses are reduced. The invention describes the application of power to a heating element through high-speed switching and pulse. It is based on the principle of being controlled by width modulation, and the current 20 a network that eliminates harmonic and flicker problems encountered in techniques. It offers a method that provides compatible and precise power control. DETAILED EXPLANATION OF THE WORKING PRINCIPLE AND METHODOLOGY OF THE INVENTION. EXPLANATION The method developed within the scope of the invention converts the voltage taken from the electrical grid into a classical voltage. cutting, delaying or cutting the waveform as in techniques not by preventing alternations; but on the basis of high-frequency switching 5 time-axis control based on pulse width modulation This approach is based on the principle that the voltage applied to the load... Instead of directly changing the amplitude, the duration of voltage application is controlled. The average power value is adjusted by this method. This allows the heater to function properly. The power applied to the resistor is precisely controlled, and the 10 drawn from the grid... The continuity of the current is preserved. The alternating voltage received from the electricity grid has a sinusoidal waveform. It is constantly and gradually changing over time. The current In these techniques, this waveform is cut, certain sections are blocked, or phased out. It is broken down by applying a delay. As a result of these processes, 15 is removed from the network. The current drawn becomes irregular and intermittent; this situation leads to harmonic components. This can cause the flicker effect to occur due to the increase in power and sudden power changes. is happening. In this invention, the waveform of the mains voltage is preserved as much as possible, and the power... control, by applying the voltage in a controlled manner along the time axis 20 This is achieved using pulse width modulation. In this technique, the power switching element within a specific time period By changing the ratio of the time spent in transmission to the time spent in cut-off, the load is adjusted. The average amount of energy transferred is adjusted. In this context, the method described in the invention can be completed with the following steps: 25 is being carried out: 16 Step 1 – Obtaining the mains voltage A sinusoidal alternating voltage from the electrical grid is applied to the system input. Step 2 – Voltage Processing The voltage in question varies depending on the application type: 5 It can be made unidirectional by passing it through a full-wave rectifier circuit, or It can be used directly without undergoing any straightening process. Step 3 – Determining the power or temperature value Temperature value or system parameters specified by the user. The required power level is calculated accordingly. This value is 10 to be applied to the resistor. It represents the average amount of energy. Step 4 – Generating the pulse width modulation signal A pulse width modulation signal corresponding to the specified power level is generated. This signal indicates that the power switching element must remain on for a specific period. It determines the duration and the closure period. 15 Step 5 – Driving the power switching element The generated modulation signal is applied to a power semiconductor element, and this element It performs on / off operations at a high frequency. Step 6 – Controlled application of voltage to the resistor. 17 While the switching element is conducting, voltage is applied to the resistance. It is not applied during the cutting process. This process is performed at a high frequency. Because this occurs, energy transfer is spread over time. Step 7 – Formation of average power Due to the physical and thermal properties of the resistor, high-frequency switching 5 The effects are not directly felt, and the applied energy is perceived as an average power. This ensures that heat production becomes stable. Step 8 – Adjusting the current waveform Instead of delivering energy suddenly and in large amounts, deliver it in small time intervals. As a result of dividing and distributing it, the current drawn from the grid has a more regular character. 10 He wins. Step 9 – Reducing harmonic components High current is achieved thanks to the waveform not being interrupted and the continuity of the current being maintained. The occurrence of unwanted components with high frequency is reduced, and disruptive elements on the network are minimized. The effects are reduced. 15 Step 10 – Reducing Flicker Effects Voltage fluctuations are avoided thanks to the load not being suddenly connected to and disconnected from the grid. Vibration effects are minimized and eliminated. Step 11 – Ensuring compliance with standards Thanks to the obtained current characteristics, harmonic and flicker values ​​are standard 20 It stays within the limits and the device passes electromagnetic compatibility tests. 18 With this method, which is implemented within the scope of the invention, energy is transferred to the load instantaneously and intermittently. Not in this way; it is transferred gradually and in a controlled manner over time. Thanks to this approach, the waveform of the current drawn from the grid becomes more sinusoidal. They are brought closer together, harmonic generation is reduced, and the flicker effect is eliminated. is being removed. 5 This method also involves zero crossing point detection, phase angle shifting, or alternation. There is no need for actions such as blocking. This makes the system more stable. This ensures more reliable and more precise operation. In conclusion, the invention controls power by distorting the voltage waveform rather than by altering time. By performing high-frequency switching on its axis, it achieves both precision and accuracy. a method that provides temperature control and is compatible with the power grid It offers. DESCRIPTION OF THE FIGURES Figure 1: Block diagram of a full-wave rectified PWM controlled heater circuit. In Figure 1, the alternating voltage taken from the grid passes through a full-wave rectifier circuit of 15. by passing it through a power transistor and controlling it via pulse width modulation. The block diagram of the system relating to the application of heating element is shown. In this configuration, the PWM control unit drives the power switching element, thereby switching the resistor. It adjusts the applied force. Figure 2: Mains voltage and full-wave rectified voltage waveforms. 20 Figure 2 shows the full-wave rectification process with a sinusoidal alternating voltage at the input. The unidirectional voltage waveform obtained afterwards is shown together. This The conversion provides a suitable voltage structure for PWM control. Figure 3: PWM signal and voltage generation across the resistor. 19 Figure 3 shows the structure of the pulse width modulation signal and the power of this signal. resulting from the application of heat to the heating element via a switching element The voltage distribution is shown. Depending on the duty cycle of the PWM signal. The average power transferred to the resistor varies. Figure 4: PWM application and resistance behavior under alternating voltage. 5 Figure 5 shows the heater depending on the PWM signal applied under alternating voltage. The voltage and current distribution across the resistor is shown in this structure. Since energy is transferred by being divided along the time axis, average power control is necessary. is provided.

Claims

REQUESTS 1) In electric heaters and / or instantaneous water heaters, the heater a method for controlling the electrical power applied to a resistor method, and the method in question is; 5  A sinusoidal waveform received from the electrical grid that changes direction over time. Applying alternating voltage in this form to the system,  The alternating voltage in question can be directly applied depending on the type of application. using or via a full-wave rectifier circuit, unidirectional voltage conversion to form 10  Temperature value and / or system determined by the user. Depending on its parameters, the average power to be applied to the heating element. generating a control signal corresponding to its value,  The control signal in question must be within a specific switching period. Pulse width modulation, which determines the ratio of transmission time to cutoff time. 15 generated as a signal,  Pulse width modulation signal switching at high frequency applied to at least one power semiconductor element capable of doing so,  The power semiconductor element, in question, pulse width modulation Switching on and off at high frequency depending on the signal 20 by implementing the process of supplying the mains voltage to the heating resistor intermittently on the time axis. However, applying it at regular intervals,  As a result of this high-frequency switching process, the heater Due to the electrical and thermal properties of the resistor, the applied voltage and The current is not measured as individual switching pulses, but as an average power value of 25. its perception as such and consequently continuous and stable heat production ensuring,  Changing the duty cycle of the pulse width modulation signal In this way, the average power value applied to the heating element is precise and 30 steps involving continuous adjustment applied to the heating element 21 power; phase angle shift on the waveform of the mains voltage, without alternation interruption or period skipping operations, high frequency switching and pulse width modulation in the time axis It is a method characterized by control through division. 2) It is a method according to claim 1;  Direct use of alternating voltage or full-wave rectification,  Analog and / or digital control of the pulse width modulation signal produced by the unit,  Power semiconductor element: insulated gate bipolar transistor and / or 10 Being a complementary metal oxide semiconductor-based power transistor,  Changing the duty cycle of the pulse width modulation signal in this way the average power applied to the heating element is gradually increased. adjustment It is characterized by including its features. 15 3) A method according to claim 1, which involves heating the heater by high-frequency switching. The voltage and current applied to the resistor are given as an average power value. sensing and consequently ensuring continuous and stable heat production. It is characterized by 20 4) A method according to claim 1, where the waveform of the current drawn from the grid... by making the harmonic components closer to a sinusoidal structure characterized by the reduction and lowering of voltage fluctuations. It has been done. 25 22 5) A method according to claim 1, which involves phase angle shifting of power control. without using alternation interruption and / or period skipping methods It is characterized by its implementation. 6) A method according to claim 1, where the power switching operation is rectified. by performing it on voltage or direct alternating voltage It has been characterized. 15 25

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