JPH02189886A - High frequency induction heating device with transistor - Google Patents

Abstract

PURPOSE:To acquire large electric power by using a plurality of transistors, connecting a metallized polypropylene film capacitor and a power balancer reactor with respective transistors, taking their ends parallel, and connecting to an induction coil. CONSTITUTION:Between DC circuits 5, 6 transistors 1a-1h are furnished, and therefrom power balancer reactors 2a-2d and capacitors 3a-3d for power factor improvement and single-sided magnetization preventing are connected in series, and high frequency power is drawn out from the transistors 1a-1h. This high frequency power is borne at a work coil to enable stable operation. Large power can be acquired proportionately by increasing symmetrically circuitries of these transistors 1a-1d, power balancer reactors 2a, 2b, and differentiation elements 3a, 3b.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transistor-type high-frequency induction heating device that heats a metal forging material mainly by high-frequency induction.

(Prior Art) A conventional high-frequency induction heating device for heating a forging material uses a thyristor element.

(Problem to be solved by the invention)) In devices using thyristor elements, stable oscillation cannot be obtained over a wide range of frequencies due to commutation circuits, etc., and power control must be performed by voltage control using phase control. There will be no.

Therefore, large harmonics are generated at the stage of phase control, causing induction disturbances. In addition, the large electrical noise generated at this time can cause problems in electronic devices that operate on weak electric power, causing large electrical pollution, which has become a social problem.

Since the transistor can be turned on and off using only the Hass signal, stable oscillation can be obtained over a wide range of frequencies. Therefore, since power control can be performed and there is no need to control the power supply voltage, there is no electrical pollution caused by this.

However, unlike a thyristor, a transistor cannot obtain a large amount of power with a single element, so the only way to obtain a large amount of power is by operating many elements in parallel.

In recent years, impedance balancing has made it possible for large-capacity devices to operate stably, but since many transistors are operated in parallel, if an element is damaged, it is easy to simply connect them in parallel. If they are lined up side by side, the effects will spread to other elements, making the accident more serious. In order to prevent such accidents, incorporating a stabilizing element into each element has problems such as being cumbersome and undesirable from an economic point of view.

(Means for Solving the Problems) In order to achieve the above object, the transistor-type high-frequency induction heating device of the present invention uses a plurality of transistors as high-frequency conversion elements to improve the power factor and prevent single excitation. A metallized polypropylene film capacitor with good high-frequency characteristics as a differential element and a power balancer reactor are connected to each transistor, and their terminals are connected in parallel and guided to an induction coil to form a transistor-type high-frequency induction heating device.

Furthermore, a plurality of transistors are used as high frequency conversion elements, and a metallized polypropylene film capacitor with good high frequency characteristics is used as a differential element to improve the power factor and prevent single excitation, and a power balancer reactor is connected to each transistor. The terminals are connected in parallel and the transistor-type high-frequency induction heating device is connected to an induction coil, and the transistor-type high-frequency induction heating device is made into a unit of about 15KW.The transistor inharter block is used as a safety breaker (or safety fuse).
It can also be connected to a three-phase power supply via a high-frequency output and used as a transistor-type high-frequency induction heating device.

(Function) By connecting a capacitor and a balancer reactor to the emitter collector of the transistor, and connecting one end of the capacitor in parallel to the work coil, the additional responsibility can be made more organic than if each transistor were directly connected in parallel.

Therefore, by increasing the number of parallel transistors, a large-capacity transistor-type induction heating device becomes possible.

Furthermore, since the transistor inheater block, which is a block of transistor-type high-frequency induction heating equipment, is connected to a three-phase power supply via a safety breaker (or safety fuse) and connected to the high-frequency output, there is no possibility that the safety element will malfunction. If so, it will be detected and the oscillation will be instantly and automatically stopped.

(Example 1) The present invention will be described below according to examples shown in the accompanying drawings.

In Figure 1, between the DC circuit +51 (61), the transistor (Ia) (lb) (lc) (ld) (
le) (If) (1g> (lh), and each transistor (la) (lb) (lc) (ld)
(1,e) (If) (Ig) (1h) to power balancer reactor (2a) (2b) (2c) (2d
) and a capacitor (3) to improve the power factor and prevent single excitation.
a) (3b) (3c) (3d) are connected in series as shown in the figure, and each transistor (Ia) (Ib) (
], c) (Id) (Ie) (If) (Ig) (
lh) It is possible to draw out higher frequency power.

This high frequency power is applied to the work coil (4) to enable stable operation.

Furthermore, transistors (Ia) (lb) (IC)
(1, cl), power balancer reactor (2a) (
By symmetrically increasing the circuits of the differential elements 2b) and the differential elements 3a and 3b, a proportionally large amount of power can be obtained.

That is, transistors (la) (lb) (lc)
(ld) (Ie) (If) (Ig) (lb) emitter collector with capacitor (3a) (3b)
(3c) (3d) and balancer reactor (2a
) (2b) (2c) (2d), connect one end in parallel and connect it to the work coil (4), each transistor (la) (lb) (Ic) (ld
) (le) (If) (Ig) (lh) can be made more organic than directly connecting them in parallel.

Therefore, by increasing the number of parallel coils, a large-capacity transistor type induction heating apparatus can be realized.

(Example 2) Multiple transistors (1a) as high frequency conversion elements
(11)) (IC) (Id) (le) (If
) (Ig) (lh), mechlyzed polypropylene film capacitor with good high frequency characteristics as a differential element for power factor improvement and prevention of single excitation = (3a) (3b
) (3c) (3d), power balancer reactor (
2a) (2b) (2c) (2d) are connected to each transistor, their terminals are connected in parallel, and the transistor-type high-frequency induction heating device is made by connecting them to an induction coil at 15K.
A transistor inherter block +a+ which is made into a unit of approximately W will be described below with reference to FIG.

Transistor inharter block (a) as above
) is connected to a three-phase power supply 00) via a safety breaker -θ]) (or a safety fuse), and a large amount of power is obtained without a high frequency output.

If the safety element is activated, it is detected and the oscillation is instantly and automatically stopped.

(Effects) This invention uses a plurality of transistors as high-frequency conversion elements like a double series, and a metallized polypropylene film cabaret with good high-frequency characteristics as a differential element for power factor improvement and prevention of single excitation, and a power A transistor-type high-frequency induction heating device in which a balancer reactor is connected to each transistor, the ends of which are connected in parallel, and guided to an induction coil.By balancing the impedance, multiple transistors can be effectively operated in parallel to obtain large amounts of power. That's how it is.

Furthermore, the present invention uses a plurality of 1-run sisters as high frequency conversion elements, and a metallized polypropylene film capacitor with good high frequency characteristics as a differential element for power factor improvement and prevention of single excitation, and a power balancer reactor for each transistor. Connect and take the ends in parallel,
The transistor inverter Pro-7, which is a transistor-type high-frequency induction heating device guided by an induction coil, is connected to a 3-phase power supply via a safety breaker (or safety fuse) and easily connected to high-frequency output. In addition to obtaining a large amount of power, if any one element such as a transistor is damaged, a safety breaker (or safety fuse) or other element will operate, detecting this and automatically stopping oscillation to prevent an accident. This has the effect of minimizing the spread of the spread of

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a circuit diagram showing one example of a transistor-type high-frequency induction heating device, and FIG. 2 is a circuit diagram showing another embodiment. (1) Transistor (2) Haranzer reactor (3) Capacitor (4) Work coil (5) DC circuit (6) DC circuit three-phase power supply safety breaker - High frequency output transistor inverter professional・Tsukui”ni

Claims (2)

[Claims] (1) Multiple transistors (
1), a metallized polypropylene film capacitor (3) with good high frequency characteristics as a differential element for improving the power factor and preventing single excitation, and a power balancer reactor (2) are connected to each transistor (1), and the terminals are connected to each transistor (1). A transistor-type high-frequency induction heating device characterized by connecting the transistors in parallel and leading them to an induction coil. (2) Multiple transistors (
1), a metallized polypropylene film capacitor (3) with good high frequency characteristics as a differential element for improving the power factor and preventing single excitation, and a power balancer reactor (3) are connected to each transistor (1), and the terminals are connected to each transistor (1). Transistor inverter block (a), which is a transistor-type high-frequency induction heating device connected to an induction coil and connected to a unit of about 15KW, is connected to a three-phase power supply (a) through a safety breaker (11) (or safety fuse).
10) and a high frequency output (12).