KR-20260063234-A - SELF-DIAGNOSIS METHOD OF GAS INJECTION HEAT PUMP SYSTEM FOR VEHICLE AND CONTROL DEVICE THEREOF

KR20260063234AKR 20260063234 AKR20260063234 AKR 20260063234AKR-20260063234-A

Abstract

A self-diagnosis method for a vehicle gas injection heat pump system and a control device thereof are disclosed. A self-diagnosis method for a gas injection heat pump system for a vehicle according to an embodiment of the present invention comprises: a step of collecting operating information necessary for self-diagnosis of the gas injection heat pump system from various sensors while the vehicle is in operation; a step of entering a gas injection (G/I) self-diagnosis mode when operating a heating mode based on the operating information; a step of forcibly operating a NON-G/I mode for a certain period of time at the beginning of entering the G/I self-diagnosis mode and switching to operating a G/I mode after the certain period of time; and a step of measuring the increase in refrigerant pressure discharged from the compressor and supplied to the indoor unit side before and after the operation of the G/I mode, and determining whether there is an abnormality in the G/I function by comparing the increase in refrigerant pressure with a management standard.

Inventors

이용한
윤중수
박종일
박남호
강병구

Assignees

현대자동차주식회사
기아 주식회사

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (10)

In a self-diagnosis method for a vehicle gas injection heat pump system of a controller, A step of collecting driving information necessary for self-diagnosis of a gas injection heat pump system from various sensors while the vehicle is in operation; A step of entering a gas injection (G/I) self-diagnosis mode when operating a heating mode based on the above operating information; A step of forcibly operating the NON-G/I mode for a certain period of time during the initial entry into the G/I self-diagnosis mode and switching to the G/I mode after the said certain period of time; and A step of measuring the increase in refrigerant pressure discharged from the compressor and supplied to the indoor unit before and after the operation of the above G/I mode, and comparing the increase in refrigerant pressure with a management standard to determine whether there is an abnormality in the G/I function; A self-diagnosis method for a vehicle gas injection heat pump system including
In paragraph 1, Forcing the above NON-G/I mode to operate is, A self-diagnosis method for a vehicle gas injection heat pump system characterized by forcibly discharging the liquid refrigerant accumulated in the gas-liquid separator through the refrigerant line for a certain period of time to prevent the liquid refrigerant accumulated in the gas-liquid separator from flowing into the refrigerant inlet of the compressor during the initial operation of the gas injection device according to the above heating mode operation.
In paragraph 1, The step of determining whether there is an abnormality in the above G/I function is, A step of determining that the G/I function is normal if the above-mentioned increase in refrigerant pressure exceeds the above-mentioned management standard; A self-diagnosis method for a vehicle gas injection heat pump system including
In paragraph 1, The step of determining whether there is an abnormality in the above G/I function is, If the above refrigerant pressure rise amount does not exceed the above management standard, a step of checking whether the above refrigerant pressure rise amount exceeds 0; and A step of diagnosing a G/I function malfunction if the above refrigerant pressure rise amount does not exceed 0; A self-diagnosis method for a vehicle gas injection heat pump system characterized by including
In paragraph 4, After the step of checking whether the above refrigerant pressure rise exceeds 0, A step of accumulating one instance of failure to meet management standards when the above refrigerant pressure rise exceeds 0; A step of checking whether the cumulative number of occurrences of failure to meet the above management standards reaches a threshold; If the above accumulated count does not reach the above threshold, the G/I self-diagnosis mode is repeated under the entry conditions for the next stage, but A step of diagnosing G/I function performance degradation when the above accumulated count reaches the above threshold; A self-diagnosis method for a vehicle gas injection heat pump system characterized by including
In paragraph 4 or 5, After the step of diagnosing the above-mentioned G/I function abnormality or G/I function performance degradation, A step of displaying a diagnosis result and a maintenance (after-sales service) recommendation message through a vehicle terminal to alert the driver; and A step of transmitting the above diagnostic results to a connected car service server to provide the driver with active vehicle maintenance reservation and in-car repair services; A self-diagnosis method for a vehicle gas injection heat pump system characterized by further including
In paragraph 1, The step of entering the self-diagnosis mode described above is, A self-diagnosis method for a gas injection heat pump system for a vehicle, characterized by entering the G/I self-diagnosis mode simultaneously with the operation of the heating mode of the heat pump when the condition is satisfied that the coolant temperature (T2) and the outside temperature (T1) based on the above driving information are the same and the air conditioner set temperature is higher than the indoor temperature (T3).
A heat pump that provides heating and cooling modes by utilizing high and low temperatures, respectively, generated during the refrigerant circulation process passing through a compressor, indoor unit, expansion valve, outdoor unit, and heat exchanger within the vehicle; A gas injector device that operates selectively during the heating mode of the heat pump and additionally injects some gaseous refrigerant extracted through phase separation after expanding the refrigerant that has passed through the indoor unit into the compressor to increase the temperature and flow rate of the refrigerant discharged to the indoor unit; and A controller that measures the increase in refrigerant pressure discharged from the compressor and supplied to the indoor unit before and after the operation of the Gas Injection (G/I) mode of the above gas injector device, and compares the increase in refrigerant pressure with a management standard to determine whether there is an abnormality in the G/I function; A self-diagnostic control device for a vehicle gas injection heat pump system including
In paragraph 8, The above controller is, A self-diagnostic control device for a vehicle gas injection heat pump system, characterized by forcing operation in NON-G/I mode for a certain period of time during the initial operation of the gas injector device according to the heating mode operation of the heat pump, and switching to operation in G/I mode after the said certain period of time.
In paragraph 8, The above controller is, If the above refrigerant pressure increase exceeds the above management standard, the G/I function is determined to be normal, but A self-diagnostic control device for a vehicle gas injection heat pump system characterized by diagnosing a G/I function abnormality if the above-mentioned increase in refrigerant pressure does not exceed the above-mentioned management standard.

Description

Self-diagnosis method of gas injection heat pump system for vehicle and control device thereof The present invention relates to a self-diagnosis method for a vehicle gas injection heat pump system and a control device thereof, and more specifically, to a self-diagnosis method for a vehicle gas injection heat pump system and a control device thereof that maintains system efficiency and performance through a self-diagnosis function of the gas injection heat pump system. Generally, air conditioners applied to the climate control systems of internal combustion engine vehicles provide cooling and heating functions that maintain the interior at a comfortable temperature through refrigerant circulation, regardless of external temperature changes. For example, an air conditioner provides cool air indoors using refrigerant cooled by passing through a cooling compressor and condenser (i.e., low-temperature refrigerant), and conversely, releases heat through the outdoor unit using refrigerant heated by passing through an expansion valve and evaporator (i.e., high-temperature refrigerant). In addition, the air conditioner utilizes a significant amount of thermal energy generated by the engine for indoor heating mode. However, various electric vehicles (xEVs) capable of driving using a motor and a high-voltage battery (hereinafter referred to as "battery" for convenience) must operate a heater (heating mode) without an engine heat source, and thus use electrical energy stored in the battery. In addition, electric vehicles also use stored electrical energy to cool the battery, which is vulnerable to high temperatures. Consequently, electric vehicles have a problem of reduced driving range (electric efficiency) due to the loss of electrical energy consumed for operating the heater and/or cooling the battery during winter. Meanwhile, conventional vehicle heat pump systems have been developed to solve the problem of reduced driving range of electric vehicles in winter. Unlike conventional air conditioners, which discharge the heat from refrigerant heated through an expansion valve and evaporator via an outdoor unit, conventional heat pump systems utilize this heat as a heater. In other words, heat pump systems can simultaneously provide both heating and air conditioning by utilizing the high-temperature and low-temperature refrigerants generated during the refrigerant circulation process, which involves compression, condensation, expansion, and evaporation. Furthermore, heat pump systems strive to reduce battery consumption and decrease driving range by recovering waste heat generated from external heat sources and vehicle electrical components for heating. Meanwhile, recent gas injection heat pump systems utilize technology that increases the temperature and flow rate of the refrigerant entering the indoor unit by directly injecting the phase-separated gaseous refrigerant into the compressor after expanding the high-pressure refrigerant. This offers the advantage of expected improvements in system efficiency and performance compared to conventional heat pump systems that do not utilize gas injection. However, since the application of gas injection heat pump systems involves the addition of expensive components to the vehicle and increases cost and weight compared to conventional heat pump systems, there are issues that can lead to a decline in vehicle quality and customer dissatisfaction if the expected improvements in system efficiency and performance are not maintained. Therefore, to improve vehicle quality and customer reliability, there is an urgent need for Prognostics and Health Management (PHM) measures to maintain the efficiency and performance of heat pump systems using gas injection. The matters described in this background technology section are written to enhance understanding of the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. Figure 1 schematically shows the configuration of a self-diagnostic device for a vehicle gas injection heat pump system according to an embodiment of the present invention. FIG. 2 is a block diagram schematically showing the configuration of a controller according to an embodiment of the present invention. FIG. 3 is a flowchart illustrating a self-diagnosis method for a vehicle gas injection heat pump system according to an embodiment of the present invention. FIG. 4 illustrates a method for setting management standards for self-diagnosis of a gas injection (G/I) function according to an embodiment of the present invention. Figure 5 is a graph showing the effect of self-diagnosis of a gas injection heat pump system according to an embodiment of the present invention. Below, embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The terms used herein are for the purpose o