KR20140016500A - A system of reducing energe for high frequence inductoin heating device - Google Patents

Abstract

The present invention relates to a power saving device of a high-frequency induction heating apparatus, in which a plurality of high-frequency consonance circuits (1, 2, 3, 4) consisting of a condenser (C) and a drive coil (L) are connected in parallel to power lines (l1, l2), to which power is supplied by a converter circuit from 3-phase alternating current power, wherein control switches (S1, S2, S3, S4) are respectively interposed in common at one end of the condenser (C) and the drive coil (L) of the high-frequency consonance circuits (1, 2, 3, 4) to supply or block power to the other-side power line (l2). Thus, a selective use of the high-frequency consonance circuits (1, 2, 3, 4) causes power to be saved and additionally, power can be saved by controlling voltage by the phase adjustment of a rectifier circuit. [Reference numerals] (AA) Converter input power; (BB) Converter(Frequency 100 Hz ~ 10K Hz)

Description

Power saving device of high frequency induction heating equipment {A SYSTEM OF REDUCING ENERGE FOR HIGH FREQUENCE INDUCTOIN HEATING DEVICE}

The present invention relates to a power saving device of a high frequency induction heating apparatus, and in more detail, a control switch is provided in a working coil and a condenser of a high frequency induction heating apparatus to selectively use a movable coil according to a heating range. By doing so, it is possible to reduce the power of the high frequency induction heating apparatus by preventing power waste due to the remaining heating coils.

In general, a high frequency induction heating apparatus is known that uses a high frequency induction heating apparatus composed of a resonant circuit of a coil and a condenser to heat a nonferrous metal and ferrous metal, cook food, or use other various applications.

An example of the prior art of the high frequency induction heating apparatus is as follows.

① The on-line heating apparatus by the high frequency induction heating method of Patent Registration No. 10-0191343 (announced on June 15, 1999) has a high permeability characteristic by forming a well-known heating coil for high frequency induction heating into a water-cooled tube. It is wound on the main surface of the ferrite core having a heating device to form a cooling circulation hole in the ferrite coil is to block the transfer of radiant heat to the ferrite core when heating the steel plate material on the line.

② Impinger water supply pipe fixing device for high frequency induction heating device of Registered Utility Model Registration No. 20-0228352 (announced on June 15, 2001) is a simultaneous water supply pipe for cooling the impeller mounted inside the movable coil of the high frequency induction heating device. And an impeller feed pipe fixing device for supporting the impeller, which forms an injection pipe and a recovery pipe on the support pipe support block, and forms a mounting hole in the lower part, and installs a dual water pump in the mounting hole to cool the impeller by cooling water. After cooling, the water is drained through the recovery pipe, thereby preventing thermal deformation of the impeller and cooling the metal band so that it can be piped.

③ Induction heating device of Korean Patent No. 10-0470289 (2005.02.05) is unable to accurately detect the temperature by lifting the pot when cooking while controlling temperature using a nonmagnetic pot such as aluminum. In order to prevent the pan from abnormal temperature rise, the user is advised to stop the temperature control function and manually adjust the temperature when the material detector detects that it is non-magnetic. In addition, in order to suppress the influence of self heating of the heating coil and to control the temperature of the highly precise heated object, it is possible to heat the heated object of iron type and to heat the heated object having an electrical conductivity of approximately equal or higher than the aluminum conductivity. It is provided with the 2nd heating coil which enables the heating of a 1st coil and a to-be-heated body, and cannot heat a to-be-heated body which has a conductivity substantially equal to or more than the conductivity of aluminum.

④ The power control device for high frequency induction heating device of Utility Model Publication No. 1989-0001600 (Publication No. 1989.04.06) is a high frequency induction heating device. Since the output is fluctuated by the product of the voltage and the flowing current, a separate pulse oscillator is operated according to the voltage variation of the AC input voltage by measuring the voltage of both ends of the operating coil to prevent this, and generating a constant output regardless of the AC voltage. The cooking time can be controlled by operating the device in a safe area.

⑤ Induction heating apparatus equipped with a function to prevent circuit damage due to a poor connection of induction heating coils in Korean Patent Publication No. 10-1093539 (announced on December 14, 2011) is heated by an input high frequency current to induce heating of a cooking vessel. A heating coil, a resonant capacitor connected in series with the induction coil, a rectifying and smoothing unit, an inverter unit for applying a high frequency current by switching a direct current power source, a switching controller for outputting a switching signal for controlling driving of the inverter unit; And detecting a connection state of the induction heating coil by using an electromagnetic wave attenuating unit for attenuating electromagnetic waves generated by the inverter unit and a predetermined voltage of the inverter, and determining that the induction heating coil is not correctly connected. And an overvoltage monitoring unit for stopping the operation of the switching control unit.

The prior art described above describes an impeller for guiding a metal band at the time of steel making, and a cooling means of a ferrite core or a means for stably maintaining an output power applied to a movable coil against a change in input power. The power saving means of the high frequency induction heating apparatus is not disclosed.

Conventional high frequency induction heating apparatus according to the present invention, as shown in Figure 1, a plurality of (four) high frequency of the capacitor (C) and the movable coil (L) in the power line of the frequency 100Hz ~ 10KHz supplied from the converter When the resonant circuits are connected in parallel, for example, when the operating power of all the movable coils L is 1000 kw, the operating power of each high frequency resonant circuit is 250 kw. However, in such a configuration, power is supplied to all the resonant circuits even when a part of the resonant circuit is to be operated according to the heating range, thereby increasing the power consumption.

An object of the present invention, in the high-frequency induction heating apparatus for heating a non-ferrous metal, or ferrous metal, by controlling the power supply to the movable coils of the plurality of high-frequency resonant circuits to selectively control the power supply of the movable coil according to the heating range and power consumption The present invention provides a power saving device of a high frequency induction heating device which can prevent and save power.

Another object of the present invention is to heat the heating element by using the movable coils of a plurality of high frequency resonant circuit, and then, when the heated object is moved to one side by the feeder, the power of each movable coil is sequentially cut off so that the power is somewhat reduced. It is to provide a power saving device of a high frequency induction heating apparatus that can be saved.

Still another object of the present invention is to control the power of the movable coil of the high frequency resonant circuit when the voltage of the three-phase power source is used in a variable manner, thereby controlling the power of the movable coil of the high frequency resonant circuit to increase the power factor by 98% or more to save power. It is to provide a power saving device of the device.

Another object of the present invention is to control the thyristor gate of the converter circuit of the power supply of the high frequency induction heating apparatus to reduce the phase of the voltage and current difference by about 30 ° from the normal phase of 180 ° to adjust the voltage to save power It is to provide a power saving device of a high frequency induction heating device.

Typically, the means for saving power in electrical devices are three ways to reduce voltage, reduce current, or increase power factor.

The present invention relates to a high frequency induction heating apparatus in which a plurality of resonant circuits composed of a capacitor and a movable coil are connected in parallel to a power line supplied with a high frequency power source having a frequency of 100 Hz to 10 KHz by a converter circuit from a three-phase AC power source.

According to a first aspect of the present invention, a plurality of capacitors connected to the high frequency power line and a control coil are provided in common at one end of the movable coil, and a plurality of capacitors and a capacitor switch are provided on one side of the high frequency power source in addition to the existing direct thermal capacitor. It is composed.

According to the first invention of the present invention, in the case of using a plurality of high frequency resonant circuits in total, respective control switches are connected to heat the heated object by high frequency induction heating of the movable coil. When you want to stop the induction heating, when pushed out by the pushing cylinder (pusher cylinder), the switch of each movable coil is opened in order in order to move from one side to the other side, turn off the power to push the heating body During ejection, the push cylinder is not heated by the movable coil. The opening / closing operation of the control switch can detect the movement of the object simply by adding a detection switch to automatically open and close the control switch of each of the movable coils.

When the heating range is narrow, power is supplied by selecting only the movable coil of the heating range required by the control switch without using all the movable coils.

The control switch of the remaining movable coil is open, so the power supply is cut off and there is no power consumption.

At this time, since one side of the converter input line is provided with a plurality of series capacitors and capacitor switches in addition to the original series capacitor, the capacitor resistor of the series capacitor is controlled by increasing or decreasing the number of use of the high frequency oscillating circuit movable coil and the capacitor. It helps to smoothly resonate with the movable coil side.

 In this way, when the heating element is heated by supplying power to all of the plurality of high frequency induction movable coils, the power of the movable coil at the corresponding position is cut off in order to correspond to the movement of the heating element. The power consumption can be reduced compared to the power supply to the heating coil.

In addition, since the power is supplied only to the coil using some high frequency induction heating coil and the control switch of the remaining movable coil is opened and the power is cut off, the present invention is compared with the power supply to all conventional movable coils and capacitors. In the same work condition to prevent wasted power can reduce the unnecessary power consumed by that much.

In addition, the voltage of the three-phase power supply may be arbitrarily set by the user such as 380v, 440v, 575v, 720v, 840v, and the like. At this time, since the power is the product of the voltage and the current, when the voltage is lowered, the current value is increased and the power factor is changed. In addition, since the power factor is lowered by changing the frequency of the converter and adjusting the induction heating temperature of the heating coil, a rectifier circuit of 98% or more is used. Increasing the power factor will eventually save power.

The second invention of the present invention controls the thyristor gate signal of the current meeting provided in the input terminal of the three-phase power source of the high frequency induction heating apparatus, so that the difference between the voltage and the current is 180 degrees or less, for example, 30 degrees lower than the normal phase of 180 degrees. The power is saved by adjusting the voltage by adjusting the phase to 150 °.

On the other hand, if the phase of the power supply is adjusted as described above, the power factor is lowered according to the voltage fluctuation and loss of power is generated. Therefore, the power factor is 95% or more rectification circuit and by adjusting the movable coil and the condenser to obtain the required power of 95% or more power factor, it is possible to eventually achieve a power saving effect.

As described above, a rectifier circuit having a power factor of 95% or more at a low voltage by phase adjustment by a thyristor gate of a simultaneous rectification circuit that reduces waste power of a high frequency induction heating apparatus by combining the first invention and the second invention of the present invention. You can reduce the power consumption by making a.

In the present invention, since a plurality of movable coils and capacitors connected in parallel to the power line supplied from the converter are connected through a control switch, the movable coils can be selectively used, and the capacity of the plurality of series heat capacitors connected to the input terminal of the power source is converted into a capacitor switch. By controlling and coordinating with the resonant action of the movable coil, the power of the high frequency induction heating apparatus can be reduced.

In addition, by adjusting the input signal of the thyristor gate of the full-wave rectifier provided on the power input side, it adjusts the phase of the thyristor to 180 ° or less from 180 ° phase of the thruster to make the rectifier circuit with the power factor of 95% or more to induce high frequency. There is an effect that can reduce the power of the heating device.

1 is a diagram illustrating a conventional general high frequency induction heating apparatus circuit
Figure 2 is an illustration of a circuit of the high frequency induction heating apparatus of the present invention
3 is an exemplary diagram of a converter circuit and an oscillation system circuit of the present invention.
4 is a three-phase voltage and waveform diagram
Figure 5 is a rectified waveform diagram of three-phase voltage by the rectifier circuit of the present invention
6 is a phase adjusted waveform diagram

As shown in Fig. 2, the capacitor C and the movable coil (1) are supplied from the three-phase AC power supply to the power supply line L1 (L2) supplied by the converter circuit through a series capacitor C1 by a high frequency power source having a frequency of 100 Hz to 10 KHz. In the high frequency induction heating apparatus in which a plurality of high frequency resonant circuits (1) (2) (3) (4) composed of L) are connected in parallel,

Control switches S1, S2, S3, and S4 are commonly interposed at one end of the capacitor C and the movable coil L of the high frequency resonant circuits 1, 2, 3, and 4, respectively. The power is connected to the other side power line (l2) to be opened and closed.

At the front end of the resonant circuit 1, a plurality of series capacitors C2 and C3, in addition to the series capacitor C1 based on one power line L1, are connected to each series capacitor by capacitor switches K1 and K2. The circuit of (C2) and (C3) is interrupted.

According to the present invention, when a plurality of high frequency resonant circuits 1, 2, 3, and 4 are used in their entirety, each control switch S1, S2, S3, S4 is connected to a capacitor ( The to-be-heated body (not shown) is heated by the high frequency induction heating generated by the resonance of C) and the movable coil (L). In order to stop the high frequency induction heating, when the cylinder pushes the heating body while being pushed while being cooled by the cooling means, the detector not shown when the cylinder reaches the No. 1 resonant circuit 1 side. The control switch S1 of the first resonant circuit 1 is opened in accordance with the detection signal of the first resonant circuit to cut off the power supply of the movable coil L of the first resonant circuit, and the push-out cylinder is the second resonant circuit 2 side. When the control switch (S2) of the second resonant circuit (2) is reached in accordance with the detection signal of the detector, the power supply of the movable coil (L) of the second resonant circuit (2) is cut off sequentially to the power supply of each resonant circuit Is blocked.

In this way, while the heating body moves the plurality of high frequency induction heating units, the heating body in the resonant circuit position is still maintained, but the movable coil of the resonant circuit at the same position is located on the end side of the heating body moved by the pushing cylinder. Power can be cut off to prevent wasting power and save power.

 When the heating range is narrow, some of the plurality of high frequency resonant circuits 1, 2, 3 and 4 operate the resonant circuits 1 and 2, and the remaining resonant circuits 3 and 4 are movable coils. Open the control switches S3 and S4 at (L) to cut off the power supply to prevent current consumption.

When the plurality of high frequency resonant circuits of the high frequency induction heating apparatus are operated as a whole, and when they are partially operated, that is, the overall opening and closing operations of the control switches S1, S2, S3, and S4 and the opening and closing operations of the partial control switches. In accordance with this, since there is a difference in the power load, the series capacitors C1 and C2 are interrupted by interrupting the switches K1 and K2 of the series capacitors C2 and C3 corresponding to the power load. The capacitance resistance of the resonant circuit by C3) is varied to allow the resonant circuit to operate smoothly.

In this way, when the heating element is heated by supplying power to all of the plurality of high frequency induction movable coils, the power of the movable coil at the corresponding position is cut off in order to correspond to the movement of the heating element. The power consumption can be reduced compared to the power supply to the heating coil.

In addition, the voltage of the three-phase power source is set by the user arbitrarily, such as 380v, 440v, 575v, 720v, 840v, etc. in order to save power in accordance with the heating conditions of the non-ferrous metal or ferrous metal. At this time, since power is the product of voltage and current, when the voltage is lowered, the current value is increased and the power factor is changed. In addition, since the power factor is lowered by changing the frequency of the converter and adjusting the induction heating temperature of the heating coil, a rectifier circuit of 98% or more is used. Increasing the power factor will eventually save power.

As shown in Fig. 3, the rectifier circuit 5 for full-wave rectifying the three-phase (R) (S) (T) power supplying power to the high frequency induction heating apparatus is constituted by a thyristor (SCR) element. The three-phase voltage and waveforms shown in FIG. 4 are rectified by the waveforms shown in FIG. 5 by the rectifier circuit 5.

At this time, by lowering the phase of the voltage difference and the current difference of the three-phase power source used as the power source of the high frequency induction heating device to adjust the voltage can be used to lower the power. In other words, in order to adjust the voltage of the three-phase alternating current, the gate G of the thyristor SCR provided in the rectifier circuit 5 of the converter circuit shown in FIG. Adjust the phase to 150 ° in phase to achieve a phase difference of 30 °. The phase-adjusted waveform forms a waveform that is cut out as indicated by an oblique line in a portion of the waveform as shown in FIG. 6, and the voltage is adjusted according to the phase adjustment.

On the other hand, if the phase of the power supply is adjusted as described above, the power factor is lowered according to the voltage variation, and a loss of power is generated. Therefore, the power factor is 95% or more rectification circuit and by adjusting the movable coil and the condenser to obtain the required power of 95% or more power factor, it is possible to eventually achieve a power saving effect.

As described above, a rectifier circuit having a power factor of 95% or more at a low voltage by phase adjustment by a thyristor gate of a simultaneous rectification circuit that reduces waste power of a high frequency induction heating apparatus by combining the first invention and the second invention of the present invention. It can reduce the power consumption.

1,2,3,4: Resonant Circuit
5: rectification circuit
C: Condenser
L: Movable Coil
SCR: Surista
K1, K2: Capacitor Switch
S1, S2, S3, S4: Control Switch
ℓ1, ℓ2: power line

Claims (3)

A plurality of high frequency frequencies comprising a condenser C and a movable coil L on a power supply line L1 (L2) supplied by a converter circuit from a three-phase AC power source with a frequency of 100 Hz to 10 KHz through a series capacitor C1. In the high frequency induction heating apparatus in which the resonant circuits (1) (2) (3) (4) are connected in parallel,
Control switches S1, S2, S3, and S4 are commonly disposed at one end of the capacitor C and the movable coil L of the high frequency resonant circuits 1, 2, 3, and 4, respectively. A power saving device of a high frequency induction heating apparatus, characterized in that the power supply is connected to the other power line (2) so as to be openable and open, thereby reducing power by selective use of a resonant circuit.
The method of claim 1,
A plurality of series capacitors C2 and C3 are connected together with the capacitor switches K1 and K2 in parallel with the series capacitor C1 provided on one power line L1 at the front end of the high frequency resonant circuit 1 to resonate the circuit. Power saving device of the high frequency induction heating apparatus, characterized in that configured to vary the capacity resistance of the furnace.
The method of claim 1,
By controlling the thyristor (SCR) gate constituting the rectifier circuit 5 of the three-phase (R) (S) (T) power supplying power to the high frequency resonant circuit (1) (2) (3) (4) A power saving device of a high frequency induction heating apparatus, characterized in that the voltage is adjusted by adjusting the phase in a range of 30 ° from 180 ° phase.

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