KR102645545B1 - Heator device - Google Patents

Abstract

A heater device according to an embodiment of the present invention includes a leg in which a power source supplying power, a first switching element, and a resistance element are connected in series, and the power supplied from the power source based on the operation of the first switching element is used to A heating unit that generates heat in a resistance element, a second switching element, a blocking unit that blocks the current flowing in the heating unit when an overcurrent occurs, and a first gate driver that supplies a first switching voltage to the first switching element. It includes a second gate driver that supplies a second switching voltage to the second switching element, and a control unit that controls operations of the first switching element and the second switching element, wherein the heating unit has a first stage and the power supply unit. It is connected to, and the second end is connected to the blocking unit.

Description

Heater device {HEATOR DEVICE}

The embodiment relates to a heater device.

Cars are equipped with an air conditioning system to control the indoor air temperature. An air conditioning system keeps the interior warm by generating warmth from a heater core in winter, and keeps the interior cool by generating cold air from an evaporator in summer.

Figures 1 and 2 are schematic diagrams showing the general circuit structure of a conventional heater controller.

The conventional heater controller controls the current to flow in each leg (leg, 12) by control switching elements (SW1 to SW4), and supplies power to the resistive loads (R1 to R4) located at the top of the control switching elements (SW1 to SW4). It generates heat by generating loss (P = I ² XR).

If the control switching elements (SW1 to SW4) located in each leg 12 are damaged due to electrical stress or overheating, they may be shorted and operate as a constant current circuit. At this time, since the current limited by the resistive loads (R1 to R4) continues to flow in the circuit, an uncontrolled overload is generated in the vehicle power source 11. To prevent this, a separate short circuit prevention switching element 13 can be used to prevent the heater controller from operating as a short circuit. The control switching elements (SW1 to SW4) and the short-circuit prevention switching element 13 are implemented through gate drivers 14-1 and 14-2 that control each.

In the case of the heater controller of FIG. 1, a floating phenomenon occurs in the short-circuit prevention switching element 13, so a circuit with a bootstrap structure of FIG. 2 is generally used to drive the short-circuit prevention switching element 13. do. In the half-bridge structure as shown in Figure 2, when the switching elements (SW1 to SW4) on the low side are turned on, the bootstrap diode (D _boot ) is turned on and the bootstrap capacitor (C _boot ) is charged, and the switching element 13 on the high side can be driven using the power of the charged bootstrap capacitor (C _boot ).

However, in the structure of the heater controller as shown in Figures 1 and 2, when the switch elements (SW1 to SW4) on the low side are turned on, a voltage of tens to hundreds of [V] is generated on both ends of the resistive load due to the current flowing in the leg. As a result, a reverse voltage is applied to the bootstrap diode (D _boot ), resulting in the bootstrap capacitor (C _boot ) not being able to be charged.

In addition to the bootstrap circuit, a separate isolated power source, an insulated structure, or a charge pump structure circuit can be used, but the manufacturing cost is high and the circuit configuration becomes complicated.

The technology behind the present invention is disclosed in Korean Patent Publication No. 10-2018-0072913 (published on July 2, 2018).

The embodiment is intended to provide a heater device to prevent short circuit at the heater output terminal.

The problem to be solved in the embodiment is not limited to this, and it will also include means of solving the problem described below and purposes and effects that can be understood from the embodiment.

A heater device according to an embodiment of the present invention includes a power supply unit that supplies power, a leg in which a first switching element and a resistance element are connected in series, and the power supplied from the power supply unit based on the operation of the first switching element is used to A heating unit that generates heat in a resistance element, a second switching element, a blocking unit that blocks the current flowing in the heating unit when an overcurrent occurs, and a first gate driver that supplies a first switching voltage to the first switching element. It includes a second gate driver that supplies a second switching voltage to the second switching element, and a control unit that controls operations of the first switching element and the second switching element, wherein the heating unit has a first stage and the power supply unit. It is connected to, and the second end is connected to the blocking unit.

A first end of the resistor element is connected to the power supply, a first end of the first switching element is connected to a second end of the resistor element, and a second end is connected to the first gate driver, The third stage may be connected to the blocking unit.

The heating unit includes a plurality of legs, and the plurality of legs may be connected in parallel to each other.

The second switching element may have a first end connected to the heating unit, a second end connected to the second gate driver, and a third end connected to the ground terminal.

It may further include a current sensing unit that detects the magnitude of the current flowing through the heating unit.

The current sensing unit may be disposed between the second switching element and the ground terminal.

The control unit compares the size of the current detected by the current sensing unit with a preset threshold, and when the size of the current exceeds the threshold, the second gate driver may control the second switching element to be opened. .

The first switching element and the second switching element may include an insulated gate bipolar mode transistor (IGBT) and a metal oxide semiconductor field effect transistor (MOSFET).

According to the embodiment, it is possible to prevent a short circuit occurring at the output terminal of the heater device. In addition, since the switch for short circuit prevention can be controlled without arranging a separate control circuit, there is an advantage in simplifying the device configuration, increasing durability, and reducing manufacturing costs.

The various and beneficial advantages and effects of the present invention are not limited to the above-described content, and may be more easily understood through description of specific embodiments of the present invention.

Figures 1 and 2 are schematic diagrams showing the general circuit structure of a conventional heater controller.
Figure 3 is a schematic diagram showing the configuration of a heater device according to an embodiment of the present invention.
Figure 4 is a diagram for explaining the driving circuit of the control unit according to an embodiment of the present invention.

Since the present invention can be subject to various changes and can have various embodiments, specific embodiments will be illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Terms containing ordinal numbers, such as second, first, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, the second component may be referred to as the first component without departing from the scope of the present invention, and similarly, the first component may also be referred to as the second component. The term and/or includes any of a plurality of related stated items or a combination of a plurality of related stated items.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

Hereinafter, embodiments will be described in detail with reference to the attached drawings, but identical or corresponding components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted.

Figure 3 is a schematic diagram showing the configuration of a heater device according to an embodiment of the present invention.

Referring to FIG. 3, the heater device 100 according to an embodiment of the present invention includes a power supply unit 110, a heating unit 120, a blocking unit 130, and a control unit 140, and a current sensing unit 150. It may further include.

The power supply unit 110 supplies direct current voltage. The power supply unit 110 may be implemented as a device capable of supplying power, such as a battery, but is not limited thereto.

The heating unit 120 generates heat through power supplied from the power supply unit 110. Specifically, the heating unit 120 includes a leg where the first switching element 122 and the heating element 121 are connected in series.

First, the first switching element 122 transfers the power supplied from the power supply unit 110 to the heating element 121 based on the switching operation. That is, the first switching element 122 transmits or blocks power from being transmitted to the heating element 121 depending on the switching operation. The first switching element 122 may include an insulated gate bipolar mode transistor (IGBT) and a metal oxide semiconductor field effect transistor (MOSFET).

Next, the heating element 121 generates heat through the power supplied from the power supply unit 110. The heating element 121 may be implemented as a single element or may have a structure in which a plurality of heating elements 121 are connected. The heating element 121 may be implemented as a Positive Temperature Coefficient (PTC) element, but is not limited thereto, and may also be implemented as an element that dissipates heat through power consumption.

Looking at the structure of the heating unit 120, the first end of the heating unit 120 may be connected to the power supply unit 110 and the second end may be connected to the blocking unit 130. That is, as the first end of the leg is connected to the power supply unit 110 and the second end is connected to the blocking unit 130, the heating unit 120 will be disposed between the power supply unit 110 and the blocking unit 130. You can.

According to one embodiment, as shown in FIG. 3, the first end of the heating element 121 may be connected to the power supply unit 110 and the second end may be connected to the first end of the first switching element 122. Also, the second end of the first switching element 122 may be connected to the first gate driver 141, and the third end may be connected to the blocking unit 130.

According to another embodiment, unlike what is shown in FIG. 3, the positions of the heating element 121 and the first switching element 122 may be swapped. That is, the first switching element 122 has a first end connected to the power supply unit 110, a second end connected to the first gate driver 141, and a third end connected to the first end of the heating element 121. can be connected to The second end of the heating element 121 may be connected to the blocking unit 130.

Both of the above embodiments have the same arrangement structure in that the heat dissipation unit is disposed between the power supply unit 110 and the blocking unit 130.

Meanwhile, the heating unit 120 may include a plurality of legs, as shown in FIG. 3, and the plurality of legs may be connected in parallel. Accordingly, each of the plurality of legs can operate independently of each other, and thus the temperature of the heater device 100 can be controlled differently.

When overcurrent occurs, the blocking unit 130 blocks the current flowing in the heating unit 120.

At this time, the blocking unit 130 may include a second switching element 131 to block the current flowing in the heating unit 120. Here, the second switching element 131 may include an insulated gate bipolar mode transistor (IGBT) and a metal oxide semiconductor field effect transistor (MOSFET).

Looking at the structure of the blocking unit 130, the first end of the second switching element 131 is connected to the heating unit 120, the second end is connected to the second gate driver 142, and the third end is connected to the second gate driver 142. It may be connected to the current sensing unit 150 or the ground terminal. That is, the blocking unit 130 may be disposed between the heating unit 120 and the current sensing unit 150 or between the heating unit 120 and the ground terminal. Here, the ground terminal may be the same terminal as the ground terminal of the power supply unit 110. The second switching elements 131 may be implemented in plurality, and the plurality of second switching elements 131 may be connected in parallel to each other.

The control unit 140 performs overall control of the heater device 100. Specifically, the control unit 140 controls the operations of the first switching element 122 and the second switching element 131. To this end, the control unit 140 includes a first gate driver 141 and a second gate driver 142, and may include a controller that controls the first gate driver 141 and the second gate driver 142. there is.

First, the first gate driver 141 supplies the first switching voltage to the first switching element 122. When the heating unit 120 includes a plurality of legs, a plurality of first switching voltages may be supplied to each of the plurality of first switching elements 122 included in each of the plurality of legs.

Next, the second gate driver 142 supplies a second switching voltage to the second switching element 131.

Additionally, a controller (not shown) may control the first gate driver 141 so that the heat dissipation unit emits heat at a target temperature. In addition, the controller compares the magnitude of the current detected by the current sensing unit 150 with a preset threshold, and when the magnitude of the current exceeds the threshold, the second gate driver 142 turns on the second switching element 131. It can be controlled to open.

The current sensing unit 150 detects the magnitude of the current flowing in the heat dissipation unit. To this end, the current sensing unit 150 may include a sensing resistor.

Specifically, the current sensing unit 150 may be disposed between the blocking unit 130 and the ground terminal. However, it is not limited to this and can be placed in any location where the magnitude of the current flowing through the heating unit 120 can be detected, such as between the power supply unit 110 and the heating unit 120.

Figure 4 is a diagram for explaining the driving circuit of the control unit according to an embodiment of the present invention.

Referring to FIG. 4, the control unit 140 includes a first gate driver 141 for controlling the first switching element 122 and a second gate driver 142 for controlling the second switching element 131. and may include a gate driver power supply 143 for driving the first gate driver 141 and the second gate driver 142.

At this time, the third terminal of the second switching element 131, which controls the entire current flow flowing through the heating unit 120, is connected to the ground terminal, so a floating phenomenon does not occur. Accordingly, when the second switching element 131 is turned on, the second switching element 131 can perform a switching operation even if the second gate driver 142 directly transfers the voltage supplied by the gate driver power. In other words, there is no need to separately arrange a bootstrap circuit, etc. to eliminate operation errors of the switching element due to the floating phenomenon. Accordingly, the circuit structure of the heater device 100 can be simplified, and thus the volume, weight, and manufacturing cost can be reduced.

The term '~unit' used in this embodiment refers to software or hardware components such as FPGA (field-programmable gate array) or ASIC, and the '~unit' performs certain roles. However, '~part' is not limited to software or hardware. The '~ part' may be configured to reside in an addressable storage medium and may be configured to reproduce on one or more processors. Therefore, as an example, '~ part' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and 'parts' may be combined into a smaller number of components and 'parts' or may be further separated into additional components and 'parts'. Additionally, components and 'parts' may be implemented to regenerate one or more CPUs within a device or a secure multimedia card.

Although the above description focuses on the examples, this is only an example and does not limit the present invention, and those skilled in the art will be able to You will see that various variations and applications are possible. For example, each component specifically shown in the examples can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the appended claims.

100: heater device
110: power unit
120: heating unit
130: blocking part
140: control unit
150: Current sensing unit

Claims (8)

A power supply unit that supplies power,
A heating unit including a leg in which a first switching element and a resistance element are connected in series, and generating heat in the resistance element through power supplied from the power supply unit based on the operation of the first switching element;
A blocking unit that includes a second switching element and blocks the current flowing to the heating unit when an overcurrent occurs,
A current sensing unit disposed between the second switching element and the ground terminal, and
A first gate driver for supplying a first switching voltage to the first switching device and a second gate driver for supplying a second switching voltage to the second switching device, and Includes a control unit that controls operation,
The heating unit,
The first end is connected to the power supply unit, and the second end is connected to the blocking unit,
The second switching element has a first end connected to the heating unit, a second end connected to the second gate driver, and a third end connected to the current sensing unit,
The current sensing unit detects the magnitude of the current flowing from the heating unit to the ground terminal through the blocking unit,
The second gate driver controls the on-off operation of the second switching element by adjusting the voltage supplied to the second switching element,
The control unit controls the first gate driver so that the heating unit emits heat at a target temperature, and compares the size of the current detected by the current sensing unit with a preset threshold, and the size of the detected current is determined by the A heater device that controls the second gate driver to open the second switching element when the threshold is exceeded.
According to paragraph 1,
The resistance element is,
The first stage is connected to the power supply,
The first switching element is,
A heater device wherein the first end is connected to the second end of the resistor element, the second end is connected to the first gate driver, and the third end is connected to the blocking unit. According to paragraph 1,
The heating unit includes a plurality of legs,
A heater device in which the plurality of legs are connected in parallel to each other. delete delete delete delete According to paragraph 1,
The first switching element and the second switching element,
A heater device comprising an insulated gate bipolar mode transistor (IGBT) and a metal oxide semiconductor field effect transistor (MOSFET).