Control device for cooling and heating system

Abstract

The present invention relates to a control device for a cooling and heating system. The control device for a cooling and heating system according to one embodiment of the present invention is a control device for controlling a motor of an electric compressor for cooling and a positive temperature coefficient (PTC) heater for heating, and for performing control in response to removal of a power supply unit. The control device comprises: a DC capacitor for storing DC power inputted from the power supply unit; a power conversion unit having a plurality of switching elements and configured to convert the DC power stored in the DC capacitor into AC power on the basis of a switching operation to output the AC power to the motor; a PTC switching unit connected in series with the PTC heater to switch application of the DC power of the DC capacitor to the PTC heater; and a control unit positioned between the power supply unit and the DC capacitor to determine an active state of the power supply unit.

Description

Control device for heating and cooling system

[0001] The present invention relates to a control device for a heating and cooling system, and more particularly, to a control device for controlling the operation of a motor of an electric compressor for cooling and a PTC (Positive Temperature Coefficient) heater for heating, respectively.

[0002] Vehicles, home appliances, or air conditioners (hereinafter referred to as "target devices") are equipped with a heating and cooling system capable of operating both cooling and heating. These heating and cooling systems include an electric compressor, a device that compresses refrigerant for the cooling system, and a PTC (Positive Temperature Coefficient) heater for the heating system. Furthermore, the heating and cooling system also includes a control device for controlling the motor for the electric compressor and the PTC heater, respectively.

[0003] In particular, electric compressors are devices that compress refrigerant by rotating a motor powered by electricity. Electric compressors are essential for eco-friendly vehicles. For example, eco-friendly vehicles may be HEVs (Hybrid Electric Vehicles), PHEVs (Plug-in Hybrid Electric Vehicles), or EVs (Electric Vehicles).

[0004] In particular, in the case of eco-friendly vehicles, since they are vehicles that use high-capacity and high-voltage electricity, there is a problem of noise caused by electrical resonance generated by vehicle operation (hereinafter referred to as "the first problem"). In addition, in eco-friendly vehicles, there is a problem of risk of electric shock to workers (hereinafter referred to as "the second problem") because the vehicle control unit or the control unit of the electric compressor cannot detect on its own when the high-voltage connector is removed (i.e., connected or disconnected) from the outside.

[0005] In particular, the first and second problems described above may be more prominent in heating and cooling systems that control both an electric compressor for cooling and a PTC heater for heating. Of course, the first and second problems described above may also occur in heating and cooling systems for other target devices, including not only eco-friendly vehicles but also electric compressors for cooling and PTC heaters for heating.

[0006] However, the above-described content merely provides background information on the present invention and does not correspond to previously disclosed technology.

[0007] In order to solve the problems of the above-described prior art, the purpose of the present invention is to provide a control device for a heating and cooling system that is not affected by external resonance or noise.

[0008] In addition, another object of the present invention is to provide a control device for a heating and cooling system that can prevent the risk of electric shock by determining and blocking an internal circuit when a high-voltage connector is removed.

[0009] In addition, another object of the present invention is to provide a control device for a heating and cooling system that can independently detect the exact power-off state.

[0010] However, the problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0011] In order to solve the above technical problem, according to one embodiment of the present invention, a control device of a heating and cooling system is provided, which controls a motor of an electric compressor for cooling and a PTC (Positive Temperature Coefficient) heater for heating, and which performs control according to the removal of a power supply unit, the control device including: a DC capacitor for storing DC power input from the power supply unit; a power conversion unit having a plurality of switching elements and converting the DC power stored in the DC capacitor into AC power based on a switching operation and outputting the converted power to the motor; a PTC switching unit connected in series with the PTC heater and switching whether the DC power of the DC capacitor is applied to the PTC heater; and a control unit located between the power supply unit and the DC capacitor for determining the activity state of the power supply unit.

[0012] A control device of a heating and cooling system according to one embodiment of the present invention further includes a reverse voltage prevention diode, and the control unit can receive a signal from both ends of the reverse voltage prevention diode.

[0013] An inductor is included that is connected to one end of the reverse voltage prevention diode, and the reverse voltage prevention diode can be positioned so that the cathode is connected to one end of the DC capacitor and the anode is connected to one end of the inductor.

[0014] The above reverse voltage protection diode can be positioned so that the cathode is connected to one end of the DC capacitor and the anode is connected to one end of the power supply.

[0015] The above control unit can determine whether the power supply is on or off based on the voltage difference across the reverse voltage prevention diode.

[0016] The control unit can calculate the initial offset of the voltage difference across the reverse voltage prevention diode (t0), detect a section (t1) in which the voltage difference across the reverse voltage prevention diode becomes larger than the initial offset and is within a preset error rate, and determine that an abnormality has occurred in the power supply because the voltage difference across the reverse voltage prevention diode exceeds the preset error rate (t2).

[0017] The above control unit can drive a self-discharge sequence when it is determined that an abnormality has occurred in the power supply unit.

[0018] The above control unit can drive the self-discharge sequence by controlling the switching operation of the power conversion unit.

[0019] The above control unit can drive the self-discharge sequence until the voltage difference across the reverse voltage prevention diode becomes less than the preset error rate.

[0020] A control device of a heating and cooling system according to one embodiment of the present invention may be for controlling heating and cooling of an eco-friendly vehicle.

[0021] The above eco-friendly vehicle may include a HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid Electric Vehicle), or EV (Electric Vehicle).

[0022] The present invention, configured as described above, has the advantage of being able to avoid noise of a resonant frequency caused by the operation of a target device equipped with the heating and cooling system.

[0023] In addition, the present invention has the advantage of being able to detect the occurrence of a power outage on its own without a separate signal from another device.

[0024] In addition, the present invention has the advantage of being able to detect the exact point in time when the power is removed.

[0025] However, the effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0026] Figure 1 shows a schematic block diagram of a heating and cooling system (1) according to one embodiment of the present invention.

[0027] Figure 2 shows a schematic circuit diagram of a control device (100A) according to the first embodiment of the present invention.

[0028] Figure 3 shows a schematic circuit diagram of a control device (100B) according to a second embodiment of the present invention.

[0029] Figure 4 shows a schematic circuit diagram of a control device (100C) according to a third embodiment of the present invention.

[0030] Figure 5 shows a schematic circuit diagram of a control device (100D) according to the fourth embodiment of the present invention.

[0031] FIG. 6 is a drawing explaining the voltage difference across the two terminals of a reverse voltage prevention diode when a connector is removed according to one embodiment of the present invention.

[0032] FIG. 7 is a drawing explaining the order of performing a self-discharge sequence according to one embodiment of the present invention.

[0033] FIG. 8 and FIG. 9 are drawings explaining a resonant frequency band according to one embodiment of the present invention.

[0034] The description of the present invention is merely an example for structural and functional explanation, and therefore, the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, since the embodiments can be modified in various ways and can take various forms, the scope of the present invention should be understood to include equivalents that can realize the technical idea. In addition, the purposes or effects presented in the present invention do not mean that a specific embodiment must include all of them or only such effects, and therefore, the scope of the present invention should not be construed as being limited thereby.

[0035] Meanwhile, the meaning of the terms described in this application should be understood as follows.

[0036] Terms such as "first" and "second" are intended to distinguish one component from another, and the scope of the rights should not be limited by these terms. For example, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

[0037] When a component is said to be "connected" to another component, it should be understood that while it may be directly connected to that other component, there may also be other components intervening. Conversely, when a component is said to be "directly connected" to another component, it should be understood that there are no other intervening components. Similarly, other expressions describing relationships between components, such as "between" and "directly between," or "adjacent to" and "directly adjacent to," should be interpreted similarly.

[0038] Singular expressions should be understood to include plural expressions unless the context clearly indicates otherwise, and terms such as "comprises" or "have" should be understood to specify the presence of a feature, number, step, operation, component, part or combination thereof, but not to exclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0039] For each step, the identifiers (e.g., a, b, c, etc.) are used for convenience of explanation and do not describe the order of the steps. The steps may occur in a different order than stated unless the context clearly dictates a specific order. That is, the steps may occur in the same order as stated, may be performed substantially simultaneously, or may be performed in the opposite order.

[0040] The present invention can be implemented as computer-readable code on a computer-readable recording medium, and the computer-readable recording medium includes all types of recording devices that store data that can be read by a computer system. Examples of the computer-readable recording medium include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc., and also includes those implemented in the form of a carrier wave (e.g., transmission via the Internet). Furthermore, the computer-readable recording medium can be distributed across network-connected computer systems, so that the computer-readable code can be stored and executed in a distributed manner.

[0041] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted to be consistent with their meaning within the context of the relevant technology, and should not be interpreted as having an idealized or overly formal meaning unless explicitly defined herein.

[0042] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0043] Figure 1 shows a schematic block diagram of a heating and cooling system (1) according to one embodiment of the present invention.

[0044] A heating and cooling system (1) according to one embodiment of the present invention (hereinafter referred to as "the system") is a system capable of operating cooling and heating, respectively, and includes a cooling system for cooling and a heating system for heating. At this time, the cooling system may include an electric compressor (200) that is a device for compressing a refrigerant, and the heating system may include a PTC (Positive Temperature Coefficient) heater (300) that generates heat according to the PTC (Positive Temperature Coefficient) principle. For example, target devices to which the system (1) is applied may be, but are not limited to, vehicles, home appliances, air conditioners, etc.

[0045] To this end, referring to FIG. 1, the system (1) includes a control device (100), an electric compressor (200), and a PTC heater (300). At this time, the electric compressor (200) includes a motor (210) that provides power for compressing a refrigerant when power is supplied under the control of the control device (100). In addition, the PTC heater (300) is a heating element made of a barium titanate-based material having a positive temperature coefficient in which the size of the resistance increases as the temperature rises. At this time, the PTC heater (300) performs a heating operation when power is supplied under the control of the control device (100), and accordingly, when a specific temperature is reached, the resistance of the PTC heater (300) greatly increases, so that the current flowing through the PTC heater (300) decreases, thereby preventing overheating.

[0046] That is, the motor (210) and the PTC heater (300) are components that operate by power supplied under the control of the control device (100), and correspond to core components for the cooling operation of the electric compressor (200) as a cooling system and the heating operation of the PTC heater (300) as a heating system in the present system (1). At this time, the control device (100) can control the operation of the motor (210) and the PTC heater (300), respectively, through power control. That is, in the present system (1), the operation of the motor (210) and the PTC heater (300) are each controlled through one control device (100), and accordingly, the cooling and heating operation of the electric compressor (200) as a cooling system and the PTC heater (300) as a heating system can be controlled.

[0047] If the target device is a vehicle, it may be desirable for the vehicle to be environmentally friendly. Examples of environmentally friendly vehicles include, but are not limited to, a Hybrid Electric Vehicle (HEV), a Plug-in Hybrid Electric Vehicle (PHEV), or an Electric Vehicle (EV).

[0048] Figures 2 to 5 show schematic circuit diagrams of control devices (100A, 100B, 100C, 100D) according to the first to fourth embodiments of the present invention.

[0049] Referring to FIGS. 2 to 4, the control device (100) can not only perform a function of controlling the operation of the motor (210) (i.e., the “first function”), but also perform a function of controlling the operation of the PTC heater (300) (i.e., the “second function”). That is, the control device (100) can control the operation of the motor (210) and the PTC heater (300) by controlling the power supply to the motor (210) and the PTC heater (300) according to the first and second functions. To this end, the control device (100) can include a power supply unit (10), an inductor (20), a control unit (30), an inverter (40), and a PTC switching unit (50). Of course, the control device (100) can further include a noise filter unit (11).

[0050] The power supply unit (10) can receive direct current power from the battery of the target device. At this time, the direct current power of the battery may be a high voltage (e.g., 48 V). That is, the power supply unit (10) can receive a high voltage external direct current power and supply direct current power for driving the motor (210) and the PTC heater (300).

[0051] The noise filter unit (11) is a circuit configuration for removing noise from the DC power supplied from the battery and transmitting it to the DC capacitor (41). Accordingly, the noise filter unit (11) may be provided between the power supply unit (10) and the inverter (40). However, the symbol for the noise filter unit (11) is only indicated in Fig. 2.

[0052] The inverter (40) is configured to convert direct current power into alternating current power and supply it to the motor (210). To this end, the inverter (40) may include a DC capacitor (41) and a power conversion unit (42).

[0053] The DC capacitor (41) receives DC power from the power supply unit (10) and charges or discharges the DC power. Regarding this DC capacitor (41), although it is illustrated as a single capacitor in the drawing, it is not limited thereto and the DC capacitor (41) may be in the form of multiple capacitors connected in series or parallel.

[0054] The power conversion unit (42) is provided with a plurality of switching elements, and can convert the direct current power stored in the DC capacitor (41) into alternating current power based on the switching operation of each switching element and output it to the motor (210). Each switching element constituting the power conversion unit (42) can switch the direct current by the input DC capacitor (41) and output it as a phase current capable of driving the motor (210). For example, the power conversion unit (42) can convert the input direct current power into three-phase alternating current power and output it to the motor (210) by turning each switching element on or off. At this time, whether each switching element of the power conversion unit (42) is on / off can be controlled by the control unit (30). That is, a control signal for each switching element can be transmitted from the control unit (30). For example, the control signal may correspond to a PWM signal.

[0055] The PTC switching unit (50) has a switching element connected in series with the PTC heater (300), and switches whether the DC power stored in the DC capacitor (41) is applied to the PTC heater (300) based on the switching operation of the corresponding switching element. For example, the PTC switching unit (50) can operate so that the input DC power is supplied to the PTC heater (300) or the corresponding supply is cut off by turning the corresponding switching element on or off. At this time, whether the corresponding switching element of the PTC switching unit (50) is on / off can be controlled by the control unit (30). That is, a control signal for the corresponding switching element can be transmitted from the control unit (30). For example, the corresponding control signal may correspond to a PWM signal.

[0056] The control unit (30) can control the operation of the control device (100). In particular, the control unit (30) can control the performance of the first and second functions. That is, in the control device (100), the DC power supplied from the power supply unit (10) is stored on the DC capacitor (41) of the inverter (40). At this time, with respect to the first function, the power conversion unit (42) of the inverter (40) is controlled by the control unit (30), so that the DC power is converted into AC power and supplied to the motor (210), thereby driving the motor (210). In addition, with respect to the second function, the PTC switching unit (50) is controlled by the control unit (30), so that the power stored in the DC capacitor (41) is applied to the PTC heater (300), thereby driving the PTC heater (300).

[0057] To this end, the control unit (30) may include a processor (not shown) and a memory (not shown). The processor is implemented as an MCU, etc., and can control the overall operation of the power conversion unit (42) and the PTC switching unit (50) using information stored in the memory. At this time, the memory may store programs and various data for processing or controlling the processor. For example, the memory may include not only volatile memory such as S-RAM and D-RAM, but also non-volatile memory such as flash memory, ROM (Read Only Memory), and EPROM (Erasable Programmable Read Only Memory).

[0058] The control unit (30) is located between the power supply unit (10) and the DC capacitor (41) and can determine the activity status of the power supply unit (10). Of course, the control unit (30) may also be located between the power supply unit (10) and the inductor (20). When the power supply unit (10) is removed (i.e., detached), the control unit (30) can detect the voltage difference across the reverse voltage prevention diode (31) to determine an interlock. For example, the control unit (30) can detect the voltage difference across the reverse voltage prevention diode (31) at regular intervals. Here, the interlock refers to a mutually dependent connection of two functions, and can confirm whether the connector is normally connected or removed. The control unit (30) can determine whether an interlock occurs when the voltage difference across the reverse voltage prevention diode (31) exceeds a certain standard so as to perform a self-discharge sequence according to the removal of the power supply unit (10). That is, even if a signal that the connector has been removed is not received through another control device, the control unit (30) detects the voltage difference between the two terminals of the reverse voltage prevention diode (31), and if it exceeds the threshold voltage of the reverse voltage prevention diode (31) itself and the error rate of the detection unit, it determines that the connector of the power unit (10) has been removed, and can independently determine whether or not to interlock to perform a self-discharge sequence that must be performed in accordance with the removal of the connector.

[0059] FIG. 8 and FIG. 9 are drawings explaining a resonant frequency band according to one embodiment of the present invention.

[0060] The control unit (30) can receive and process signals from both ends of the reverse voltage prevention diode (31). The reverse voltage prevention diode (31) is located between the power supply unit (10) and the DC capacitor (41) and can change the series resonant frequency of the entire control device (100). Referring to FIG. 8, for example, a general vehicle-side switching frequency is formed at 5 kHz to 20 kHz, and the series resonant frequency band by the inductor (20) and the DC capacitor (41) of the control device (100) before the reverse voltage prevention diode (31) is located between the power supply unit (10) and the DC capacitor (41) is formed at about 3 kHz to 200 kHz, which may be affected by the vehicle-side switching frequency. In contrast, when the reverse voltage prevention diode (31) is located between the power supply unit (10) and the DC capacitor (41), the resonant frequency band of the control device (100) is changed to 200 kHz or more, so that the vehicle-side switching frequency can be avoided. The control unit (30) can receive the voltage difference across the reverse voltage prevention diode (31), and based on this, can determine the connection status of the power supply unit (10) with the external power supply, and when it determines that the power supply unit (10) is disconnected from the external power supply, it can determine an interlock and drive a self-discharge sequence, which will be described in detail below.

[0061] The inductor (20) can be connected to one end of a reverse voltage prevention diode. The inductor (20) can function as a filter to block the AC component and pass only the DC component together with the DC capacitor (41).

[0062] The reverse voltage prevention diode (31) can be positioned so that the cathode is connected to one end of the DC capacitor (41) and the anode is connected to one end of the inductor (20). For example, as described above, the reverse voltage prevention diode (31) allows current to flow from the anode to the cathode and not from the cathode to the anode, so the inductor (20) can be positioned at the anode and the DC capacitor (41) can be positioned at the cathode, allowing current to flow.

[0063] That is, the reverse voltage prevention diode (31) can only pass forward current flowing from the inductor (20) toward the DC capacitor (41) and not pass reverse current flowing in the opposite direction. In addition, the reverse voltage prevention diode (31) can avoid the overall system resonance frequency of the control device (100) to a high frequency band so as not to overlap with the vehicle-side switching frequency. For example, the reverse voltage prevention diode (31) can space the system resonance frequency band of the control device (100) by 200 kHz or more.

[0064] The control unit (30) can determine whether the power supply unit (10) is on or off based on the voltage difference across the reverse voltage prevention diode (31). Fig. 6 is a diagram explaining the voltage difference across the reverse voltage prevention diode when a connector is removed according to an embodiment of the present invention. Referring to Fig. 6, the control unit (30) can detect the voltage across the reverse voltage prevention diode (31). At this time, the control unit (30) can determine that an interlock has occurred due to the connector removal if the voltage value across the reverse voltage prevention diode (31) is compared and exceeds a preset error rate, which will be described in detail below.

[0065] In one embodiment, the control unit (30) calculates the initial offset of the voltage difference across the reverse voltage prevention diode (31) (t0), detects a normal state section (t1) in which the voltage difference across the reverse voltage prevention diode (31) is within a preset error rate, and determines that an abnormality has occurred in the power supply unit (10) because the voltage difference across the reverse voltage prevention diode (31) exceeds the threshold voltage difference of the diode and the error rate of the detection unit. For example, the control unit (30) can calculate the initial offset, such as the threshold voltage drop due to the reverse voltage prevention diode. This voltage drop due to the reverse voltage prevention diode may be different for each element, and even if the user does not directly input it, the initial offset can be calculated through the control unit (30) to detect the interlock occurrence point with higher accuracy. For example, the control unit (30) can detect a section (t1) in which the initial offset voltage is 0.7 V and is within a preset error rate, and can determine that an interlock has occurred in the power supply unit (10) by detecting a section (t2) in which the voltage difference across the reverse voltage prevention diode (31) exceeds the preset error rate. In other words, the control unit (30) can more accurately detect the point in time when an interlock has occurred.

[0066] In one embodiment, if the control unit (30) determines that an abnormality has occurred in the power supply unit (10), it can drive a self-discharge sequence. For example, if the control unit (30) detects a section (t2) in which the voltage difference across the reverse voltage prevention diode (31) exceeds a preset error rate and determines that an interlock has occurred in the power supply unit (10), it can drive a self-discharge sequence to discharge the DC power stored in the DC capacitor (41) to a self-discharge section (t3).

[0067] In one embodiment, the control unit (30) can drive a self-discharge sequence by controlling the switching operation of the power conversion unit (42). FIG. 7 is a diagram explaining a sequence for performing a self-discharge sequence according to one embodiment of the present invention. Referring to FIG. 7, the control unit (30) detects the voltage across the reverse voltage prevention diode (31) (S710), and can compare whether the voltage difference across the reverse voltage prevention diode (31) is greater than a preset error rate to determine whether the connector of the power supply unit (10) has been removed (S720). If the voltage difference across the reverse voltage prevention diode (31) is greater than the preset error rate, the control unit (30) can determine that an interlock has occurred (S730). Next, the control unit (30) can perform a self-discharge sequence by rotating the motor through the switching operation of the power conversion unit (42) to consume the DC power stored in the DC capacitor (41) (S740).

[0068] In one embodiment, the control unit (30) can drive the self-discharge sequence until the voltage difference across the reverse voltage prevention diode (31) becomes within a preset error rate. For example, the control unit (30) can drive the self-discharge sequence until the voltage difference across the reverse voltage prevention diode (31) becomes less than or equal to the initial offset. That is, in addition to the forced discharge command of the upper controller, the control unit (30) can independently determine when to drive the self-discharge sequence and when to stop it, thereby driving an efficient self-discharge sequence.

[0069] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0070] The present invention can be applied to a heating and cooling system.

Claims

1. In a control device of a heating and cooling system that performs control for a motor of an electric compressor for cooling and a PTC (Positive Temperature Coefficient) heater for heating, and performs control according to the removal of the power supply unit, A DC capacitor that stores direct current power input from the above power supply; A power conversion unit having a plurality of switching elements and converting direct current power stored in the DC capacitor into alternating current power based on a switching operation and outputting the converted power to the motor; A PTC switching unit that is connected in series with the PTC heater and switches whether the DC power of the DC capacitor is applied to the PTC heater; and A control unit located between the power supply unit and the DC capacitor to determine the activity status of the power supply unit; A control device for a heating and cooling system including:

2. In paragraph 1, It further includes a reverse voltage protection diode, The above control unit is a control device of a heating and cooling system that receives signals from both ends of the reverse voltage prevention diode.

3. In paragraph 2, Including an inductor connected to one end of the above reverse voltage protection diode, The above reverse voltage protection diode is, A control device for a heating and cooling system, wherein the cathode is connected to one end of the DC capacitor and the anode is connected to one end of the inductor.

4. In paragraph 2, The above reverse voltage protection diode is, A control device for a heating and cooling system, wherein the cathode is connected to one end of the DC capacitor and the anode is connected to one end of the power supply.

5. In paragraph 2, The above control unit, A control device for a heating and cooling system that determines whether the power supply is on or off based on the voltage difference between the two terminals of the reverse voltage prevention diode.

6. In paragraph 5, The above control unit, A control device for a heating and cooling system that calculates the initial offset of the voltage difference across the reverse voltage prevention diode (t0), detects a section (t1) in which the voltage difference across the reverse voltage prevention diode becomes larger than the initial offset and is within a preset error rate, and determines that an abnormality has occurred in the power supply when the voltage difference across the reverse voltage prevention diode exceeds the preset error rate (t2).

7. In paragraph 6, The above control unit, A control device of a heating and cooling system that drives a self-discharge sequence when it is determined that an abnormality has occurred in the above power supply unit.

8. In paragraph 7, The above control unit, A control device of a heating and cooling system that drives the self-discharge sequence by controlling the switching operation of the power conversion unit.

9. In paragraph 7, The above control unit, A control device for a heating and cooling system that drives a self-discharge sequence until the voltage difference across the reverse voltage prevention diode becomes less than the preset error rate.

10. In paragraph 1, A control device for a heating and cooling system for controlling the heating and cooling of an eco-friendly vehicle.

11. In paragraph 10, The above eco-friendly vehicle is a control device for a heating and cooling system including an HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid Electric Vehicle) or EV (Electric Vehicle).

Images