Control system of DC28V and DC600V dual-power-supply air conditioner

Abstract

The invention discloses a control system of a DC28V and DC600V dual-power-supply air conditioner, an evaporation fan, a condensation fan, a compressor and a PTC (Positive Temperature Coefficient) electric heater in the dual-power-supply air conditioner are respectively powered by a DC600V power supply, a controller is powered by a DC28V power supply, and the control system further comprises a signal detection element, a compressor pre-charging element, a control device and a protection device; the controller is electrically connected with an evaporation fan, a condensation fan and a compressor in the air conditioner; the signal detection element is used for detecting the temperature and the pressure of the refrigerating system, and the signal detection element is electrically connected with a signal sampling interface of the controller; the compressor pre-charging element comprises a high-voltage connector and a pre-charging circuit, the compressor is connected with the power supply bus through the high-voltage connector and the pre-charging circuit, and the controller controls the pre-charging circuit; the control device comprises a plurality of groups of high-voltage direct-current relays, the normally open contacts are closed to enable the power supply ends of the evaporation fan, the condensation fan, the compressor and the PTC electric heater to be connected to a DC600V power supply circuit, and coils of each group of high-voltage direct-current relays are electrically connected with a control signal interface of the controller; the protection device comprises a high-voltage direct-current fuse, a high-voltage direct-current circuit breaker and a temperature relay, the protection device is electrically connected with the controller detection interface, a perfect protection function is provided for the dual-power-supply air conditioner, and the safety and reliability of the air conditioner equipment are improved.

Description

Technical Field

[0001] The invention relates to the field of air-conditioning control systems, in particular to a control system for a DC28V and DC600V dual-powered air-conditioning. Background Art

[0002] With the successful application of high-voltage DC drive technology in the construction of combat unit integration pilot projects, DC28V and DC600V dual-powered air conditioners have become new temperature regulation equipment for weapon systems. The core components of the refrigeration system of the DC28V and DC600V dual-powered air conditioners use advanced high-voltage DC electric scroll compressors and stepless high-voltage DC circulation fans and condensing fans, replacing the fixed-frequency compressors and AC variable-frequency compressors commonly used in air-conditioning equipment; the core components of the heating system use a high-voltage DC PTC electric heater arranged at the return air outlet for heating, relying on the physical property changes of the PTC material itself to adjust the heating power of the PTC electric heater, replacing the heating method of the metal electric heating tube with constant heating power embedded in the evaporator commonly used in military refrigeration equipment. Therefore, it is necessary to invent a control system that controls according to the technical characteristics of the high-voltage DC electric scroll compressor, the stepless high-voltage DC circulation fan and the high-voltage DC PTC electric heater to ensure that the temperature in the space where the weapon system is located does not fluctuate violently and improve the safety, reliability and service life of the air-conditioning equipment. Summary of the invention

[0003] The present invention provides a control system for a DC28V and DC600V dual-powered air conditioner to ensure that the air conditioner provides a comfortable working environment for equipment using high-voltage DC drive technology and improve the safety, reliability and service life of the air conditioner.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A control system for a DC28V and DC600V dual-powered air conditioner, wherein an evaporating fan, a condensing fan, a compressor, and a PTC electric heater in the dual-powered air conditioner are powered by a DC600V power supply respectively, and a controller is powered by a DC28V power supply. The control system is characterized in that the control system comprises a signal detection element, a compressor pre-charging element, a control device, and a protection device.

[0005] The controller is electrically connected to the evaporation fan, condensation fan and compressor in the dual-power air conditioner; The signal detection element includes a temperature sensor and a pressure sensor, which are used to detect the temperature and pressure in the dual-powered air conditioner, and the signal detection element is electrically connected to the signal detection interface of the controller; The compressor pre-charging element includes a high-voltage connector and a pre-charging circuit, the control module of the compressor is connected to the DC600V power supply line through the high-voltage connector and the pre-charging circuit, and the compressor pre-charging element is electrically connected to the control signal interface of the controller; The control device includes multiple groups of high-voltage DC relays, the moving contacts are closed to connect the power supply ends of the evaporating fan, the condensing fan, the compressor, and the electric heater to the DC600V power supply line, and the coils of each group of high-voltage DC relays are electrically connected to the control signal interface of the controller; The protection device includes two groups of high-voltage DC circuit breakers, wherein the main contacts of one group of high-voltage DC circuit breakers are connected to the evaporating fan and the DC600V power supply bus positive line, and the main contacts of the other group of high-voltage DC circuit breakers are connected to the condensing fan and the DC600V power supply bus positive line, and the auxiliary contacts of the two groups of high-voltage DC circuit breakers are respectively electrically connected to the overload signal detection port of the controller; Furthermore, the signal detection element includes three groups of temperature sensors, which are respectively used to detect the return air temperature, coil temperature and exhaust temperature in the dual-powered air conditioner; and also includes two groups of pressure sensors, which are respectively used to detect the high-pressure side pressure of the refrigeration system and the low-pressure side pressure of the refrigeration system in the dual-powered air conditioner. The three groups of temperature sensors and the two groups of pressure sensors are respectively electrically connected to the signal sampling port of the controller; Furthermore, the protection device also includes a temperature relay, and both ends of the moving contact of the temperature relay are electrically connected to the overheat protection signal of the controller respectively; Furthermore, the protection device also includes a plurality of groups of high-voltage DC fuses, and each group of high-voltage DC fuses is respectively connected to the compressor pre-charge element, the PTC electric heater and the DC600V power supply bus positive line.

[0006] Beneficial effects of the present invention: 1. The present invention is provided with a compressor pre-charging element and controls the start and stop timing of the high-voltage DC relay therein. Before the high-voltage DC electric scroll compressor is operated, the DC bus voltage is established by capacitor pre-charging to prevent the high-voltage DC circuit from short-circuiting when the compressor is powered on, and the impact current from damaging the power components of the main power supply circuit, thereby ensuring the safety of the weapon system and the air-conditioning equipment.

[0007] 2. The present invention communicates data with the compressor, realizes soft start of the air-conditioning equipment and adjusts the cooling capacity of the air-conditioning equipment by controlling the speed of the compressor, and ensures that the temperature is maintained near the set value. The technology is advanced, mature, reliable and energy-saving.

[0008] 3. The present invention adopts group control and time-sharing start and stop of high-voltage DC PTC electric heaters, and controls the speed of the circulating fan through a PWM speed regulation signal. It relies on the physical property changes of the PTC material itself to quickly adjust the PTC heating power to ensure that the temperature is maintained near the set value. It is simple, reliable and saves costs.

[0009] 4. The present invention is provided with protections such as compressor overcurrent, PTC overheating and overcurrent, circulating fan overload, condensing fan overload, evaporator anti-freezing, refrigeration system pressure and compressor exhaust temperature, which improves the safety, reliability and service life of the air-conditioning equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a circuit principle block diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0011] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0012] like Figure 1 As shown, this embodiment discloses a control system for a DC28V and DC600V dual-powered air conditioner, in which the evaporator fan MD1, the condenser fan MD2, the compressor MC, and the PTC electric heaters PTC1 to PTC4 are respectively powered by a DC600V power supply, that is, the positive power supply end of the evaporator fan MD1 is connected to the positive line of the DC600V power supply bus, the negative power supply end of the evaporator fan MD1 is connected to the negative line of the DC600V power supply bus; the positive power supply end of the condenser fan MD2 is connected to the DC600V power supply bus; The positive power supply of the C600V power supply bus is connected to the positive line of the DC600V power supply bus, and the negative power supply of the condensing fan MD2 is connected to the negative line of the DC600V power supply bus; the positive power supply of the compressor MC is connected to the positive line of the DC600V power supply bus, and the negative power supply of the compressor MC is connected to the negative line of the DC600V power supply bus; the positive power supply of the PTC electric heater PTC1~PTC4 is connected to the positive line of the DC600V power supply bus, and the negative power supply of the PTC electric heater PTC1~PTC4 is connected to the negative line of the DC600V power supply bus. The DC28V power supply is used to supply power to the controller AP in the dual-powered air conditioner. After the DC-DC power supply isolation and voltage stabilization in the controller AP, the DC28V power supply voltage provides DC24V voltage power supply to the high-voltage pressure sensor YCQ1, the low-voltage pressure sensor YCQ2, the CAN communication circuit of the compressor MC, and the coils of the high-voltage DC relays KA1~KA8.

[0013] This embodiment includes a controller AP, a signal detection element, a compressor pre-charging element, a control device and a protection device, wherein: The controller AP is electrically connected to the evaporator fan MD1, condenser fan MD2, and compressor MC in the dual-powered air conditioner. Specifically, the evaporator fan MD1 and the condenser fan MD2 are high-voltage DC fans with PWM speed regulation, respectively. The controller AP controls the speed of the evaporator fan MD1 and the condenser fan MD2 by controlling the duty cycle of the PWM speed regulation signal of the evaporator fan MD1 and the condenser fan MD2, thereby controlling the air volume. The compressor MC is a high-voltage DC electric scroll compressor with a built-in control module. By utilizing the adjustable and controllable speed characteristics of the high-voltage DC electric scroll compressor, the controller AP communicates with the control module CAN of the compressor MC, and controls the speed of the compressor MC through software logic, thereby controlling the soft start of the air-conditioning equipment and adjusting the cooling capacity of the air-conditioning equipment.

[0014] In addition, each group of PTC electric heaters PTC1~PTC4 has a separate output line. The controller AP controls the gear switching of the PTC electric heaters PTC1~PTC4 through group control, and controls the speed of the evaporating fan MD1 through the PWM speed regulation signal to adjust the air volume. The heating power of the PTC electric heater is adjusted depending on the changes in the physical properties of the PTC material itself.

[0015] In this embodiment, the signal detection element includes a temperature sensor RT1 for detecting the return air temperature in the dual-powered air conditioner, a temperature sensor RT2 for detecting the coil temperature in the dual-powered air conditioner, a temperature sensor RT3 for detecting the exhaust temperature in the dual-powered air conditioner, a pressure sensor YCQ1 for detecting the high-pressure side pressure in the dual-powered air conditioner, and a pressure sensor YCQ2 for detecting the low-pressure side pressure in the dual-powered air conditioner. The temperature sensor RT1, the temperature sensor RT2, the temperature sensor RT3, the pressure sensor YCQ1, and the pressure sensor YCQ2 are electrically connected to the signal sampling port of the controller AP respectively.

[0016] The controller AP automatically controls the air conditioning equipment to perform ventilation, cooling, heating and dehumidification according to the difference between the return air temperature detected by the temperature sensor RT1 in the signal detection element and the target temperature set by the controller.

[0017] In this embodiment, the compressor pre-charging element includes a pre-charging circuit and a high-voltage connector XP1. The pre-charging circuit connects the DC600V power supply bus and the controller AP. The pre-charging circuit includes a high-voltage DC fuse FU1, a high-voltage DC relay KA3, KA4, a freewheeling diode D3, D4, resistors R1~R2, and a capacitor C1. The input end of the high-voltage DC fuse FU1 is connected to the positive line of the DC600V power supply line, and the output end of the high-voltage DC fuse FU1 is connected to the contact input end of the high-voltage DC relays KA3 and KA4. After the contact output end of the high-voltage DC relay KA3 is connected in series with the resistor R1, it is connected in parallel with the contact output end of the high-voltage DC relay KA4 to one terminal of the capacitor C1, and the other terminal of the capacitor C1 is connected to the negative line of the DC600V power supply line. The two ends of the capacitor C1 are connected to the high-voltage connector XS1 at the high-voltage DC line input end of the control module of the high-voltage DC electric scroll compressor through the high-voltage connector XP1.

[0018] The signal output end of the controller AP is connected to the coils of the high-voltage DC relays KA3 and KA4 respectively. The coils of the high-voltage DC relays KA3 and KA4 are reversed and connected to the freewheeling diodes D3 and D4. The controller AP controls the start and stop timing of the high-voltage DC relays KA3 and KA4 in the compressor pre-charging element. Before the high-voltage DC electric scroll compressor is operated, the DC bus voltage is established through the capacitor C1 pre-charging to prevent the high-voltage DC circuit from short-circuiting when the compressor is powered on, and the impact current causes damage to the main circuit power devices, thereby ensuring the safety of the weapon system and air-conditioning equipment.

[0019] In this embodiment, the control device includes high-voltage DC relays KA1 to KA8, and the normally closed contact of the high-voltage DC relay KA1 is connected to the circuit between the positive power supply terminal of the evaporator fan MD1 and the positive line of the DC600V power supply bus; the normally closed contact of the high-voltage DC relay KA2 is connected to the circuit between the positive power supply terminal of the condensing fan MD2 and the positive line of the DC600V power supply bus; the normally closed contact of the high-voltage DC relay KA5 is connected to the circuit between the power supply terminal of the electric heater PTC1 and the positive line of the DC600V power supply bus; the normally closed contact of the high-voltage DC relay KA6 is connected to the circuit between the power supply terminal of the electric heater PTC2 and the positive line of the DC600V power supply bus; the normally closed contact of the high-voltage DC relay KA7 is connected to the circuit between the power supply terminal of the electric heater PTC3 and the positive line of the DC600V power supply bus; the normally closed contact of the high-voltage DC relay KA8 is connected to the circuit between the power supply terminal of the electric heater PTC4 and the positive line of the DC600V power supply bus. The controller AP is electrically connected to the coil controls of the high voltage DC relays KA1, KA2, KA5, KA6, KA7 and KA8 respectively.

[0020] In this embodiment, the protection devices include two groups of high-voltage DC circuit breakers QF1 and QF2, four groups of temperature relays ST1-ST4, and five groups of high-voltage DC fuses FU1-FU5.

[0021] In the two groups of high-voltage DC circuit breakers QF1 and QF2, the main contacts of the first group of high-voltage DC circuit breakers QF1 are connected to the line connecting the positive power supply end of the evaporating fan MD1 to the positive line of the power supply bus, and the auxiliary contacts of the first group of high-voltage DC circuit breakers QF1 are electrically connected to the overload protection signal of the controller AP. The main contacts of the second group of high-voltage DC circuit breakers QF2 are connected to the line connecting the positive power supply end of the condensing fan MD2 to the positive line of the power supply bus, and the auxiliary contacts of the second group of high-voltage DC circuit breakers QF2 are electrically connected to the overload protection signal of the controller AP. When the fan is short-circuited or overloaded, the high-voltage DC circuit breaker trips to disconnect the main contacts and auxiliary contacts, cuts off the power supply of the main circuit, and at the same time, the auxiliary contact disconnection signal is fed back to the controller AP, which stops the compressor MC and the PTC electric heater in time to ensure electrical safety.

[0022] The four groups of temperature relays ST1 to ST4 are electrically connected to the overheat protection signals of the controller AP respectively.

[0023] Among the five groups of high-voltage DC fuses FU1~FU5, the first group of high-voltage DC fuses FU1 is connected to the line where the positive power supply terminal of the pre-charging circuit of the compressor pre-charging element is connected to the positive line of the power supply bus, the second group of high-voltage DC fuses FU2 is connected to the line where the positive power supply terminal of the electric heater PTC1 is connected to the positive line of the power supply bus, the third group of high-voltage DC fuses FU3 is connected to the line where the positive power supply terminal of the electric heater PTC2 is connected to the positive line of the power supply bus, the fourth group of high-voltage DC fuses FU4 is connected to the line where the positive power supply terminal of the electric heater PTC3 is connected to the positive line of the power supply bus, and the fifth group of high-voltage DC fuses FU5 is connected to the line where the positive power supply terminal of the electric heater PTC4 is connected to the positive line of the power supply bus.

[0024] In this embodiment, the controller AP is connected to an alarm circuit. In addition to the above-mentioned overload and overheat protection, it is also provided with protection circuits such as abnormal refrigeration system pressure, abnormal compressor pre-charge and abnormal CAN communication.

[0025] In the present invention, the controller AP automatically controls the air conditioning equipment to perform ventilation, cooling, heating and dehumidification according to the difference between the return air temperature detected by the temperature sensor RT1 and the set target temperature.

[0026] When the return air temperature detected by the temperature sensor RT1 is 2°C higher than the set target temperature, the air conditioning equipment cools. Compared with the conventional air conditioning control system, the most important thing is to pre-charge the high-voltage DC electric scroll compressor to establish the DC bus voltage before operation to prevent the impact current from damaging the main circuit power components when the compressor MC is powered on.

[0027] During cooling, the moving contact of the high-voltage DC relay KA1 is closed, and the circulation fan MD1 is started. After 10 seconds, it is determined whether there is a mode switching instruction. If so, it switches to other modes. If not, it is determined whether the refrigeration conditions are met and the low-pressure YCQ2 of the refrigeration system and the CAN communication of the compressor MC are checked. If they are normal, the moving contact of the high-voltage DC relay KA2 is closed to start the condensing fan MD2. After 3 seconds, the moving contact of the high-voltage DC relay KA3 is closed. After 30 seconds, it is determined whether the pre-charge voltage of the compressor is higher than 380VDC. If it is less than 380VDC, a pre-charge fault alarm is issued. If it is greater than 380VDC, the moving contact of the high-voltage DC relay KA4 is closed, and the main power supply circuit of the compressor MC is opened. After a delay of 1 second, the moving contact of the high-voltage DC relay KA3 is disconnected, and the pre-charge is turned off. After another delay of 1 second, the controller AP sends a start-up command to the compressor MC through CAN communication, starting the speed at 2500rpm, starting with a small current, and entering cooling operation.

[0028] During the refrigeration operation, monitor whether the circulating fan MD1, condensing fan MD2, and compressor MC have overload, overcurrent and other faults, and detect whether the high-pressure pressure YCQ1 of the refrigeration system is higher than the specified value. If there is a fault, switch to protection processing, if there is no fault, continue refrigeration; determine whether there is a shutdown command, if so, stop the refrigeration, if not, continue refrigeration; determine whether there is a mode switching instruction, if so, switch to other modes, if not, continue refrigeration; determine whether it is close to the set temperature, if close to the set temperature, the controller AP controls the speed of the circulating fan MD1 and the condensing fan MD2 through the PWM speed regulation signal, adjusts the air volume of the circulating fan MD1 and the condensing fan MD2 through the speed, controls the compressor speed through CAN communication, and adjusts the cooling capacity of the air-conditioning equipment through the speed; detect whether the low-pressure pressure YCQ2 of the refrigeration system is lower than the specified value, if there is a fault and it lasts for 3s, switch to protection processing, if there is no fault, continue refrigeration.

[0029] When refrigeration stops, the speed of compressor MC is gradually reduced by 100rpm every 5s to determine whether the speed of compressor MC is lower than 10rpm. If not, continue to reduce the speed of compressor MC. If so, send a stop command to compressor MC via CAN communication after a delay of 5s, and then delay for 3s. The normally closed contact of high-voltage DC relay KA2 is disconnected, disconnecting the main power supply circuit of compressor MC; then the condensing fan stops running after a delay of 3s, and the air conditioner enters ventilation state; when cooling again, the compressor automatically starts with a delay of 3min to protect the compressor from damage.

[0030] In the present invention, when the return air temperature detected by the temperature sensor RT1 is 2°C lower than the set target temperature, the air conditioning equipment heats. Compared with the conventional air conditioning control system, the most important thing is to adopt group control, time-sharing start and stop of the high-voltage DC PTC electric heater, and control the speed of the circulating fan MD1 through the PWM speed regulation signal, thereby adjusting the air volume of the circulating fan MD1, relying on the change of the physical properties of the PTC material itself, and adjusting the PTC heating power.

[0031] During heating, the circulating fan MD1 works first. When the return air temperature is 2°C lower than the set temperature, the electric heater PTC1 is turned on to work, and the circulating fan MD1 is detected to be overloaded or overcurrent. If there is a fault, it is switched to heating and shut down. If there is no fault, it continues to heat; the electric heater PTC1 is detected to be overheated or overcurrent. If there is a fault, it is switched to protection processing. If there is no fault, it continues to heat; it is determined whether there is a shutdown command. If so, it is switched to heating and shut down. If not, it continues to heat; it is determined whether there is a mode switching instruction. If so, it is switched to other modes. If not, it continues to heat. For every 2°C lower the return air temperature than the set temperature, a group of PTC electric heaters is turned on, and the PTC2, PTC3, and PTC4 electric heaters work in turn, and the gear switching judgment is performed once per second; it is determined whether it is close to the set temperature. If it is close to the set temperature, the speed of the circulating fan MD1 is controlled by the PWM speed regulation signal, thereby adjusting the air volume of the circulating fan MD1, and the PTC heating power is adjusted depending on the physical property changes of the PTC material itself.

[0032] When heating stops, the PTC1, PTC2, PTC3, and PTC4 electric heaters are turned off in sequence, and the air conditioner enters the ventilation state; when shutting down in the heating state, the circulation fan delays working for 1.5 minutes before stopping.

[0033] In this embodiment, there is a complete protection processing design, and the protection devices include high-voltage DC fuses FU1~FU5, high-voltage DC circuit breakers QF1~QF2, temperature relays ST1~ST4; there are also signal detection elements such as evaporator coil temperature RT2, exhaust high temperature protection RT3, high-pressure pressure sensor YCQ1, and low-pressure pressure sensor YCQ2.

[0034] Among the protection devices, high-voltage DC fuses FU1~FU5 are installed in the high-voltage DC main circuit of the compressor MC and the electric heater PTC. They will melt when a short circuit or overcurrent occurs to ensure electrical safety. High-voltage DC circuit breakers QF1~QF2 are installed in the high-voltage DC main circuit of the circulation fan MD1 and the condensing fan MD2. They will trip when a short circuit or overload occurs to cut off the power supply of the main circuit. At the same time, the auxiliary contact disconnection signal is fed back to the protection interface of the controller AP. Through the software control logic, the operation of the compressor MC and the PTC electric heater is stopped in time to ensure electrical safety.

[0035] The temperature relays ST1~ST4 in the protection device are set on the PTC bracket. The temperature relays ST1~ST4 sense the evaporator surface temperature in real time. When the evaporator surface temperature is higher than the temperature relay action value, the temperature relay contacts jump open, and the switch signal is input to the protection interface of the controller AP. Through the software control logic, the control loop of the PTC electric heater is disconnected in time to prevent the evaporator surface temperature from being too high, causing the surrounding components to rise in temperature and deform, or heat accumulation to cause a fire.

[0036] The temperature sensor RT2 in the signal detection element is set on the coil of the evaporator. The temperature sensor RT2 senses the temperature of the evaporator coil in real time, and the sampled value is converted and input into the corresponding A / D channel of the controller AP. Through the software control logic, when the evaporator coil temperature RT2 is lower than -5℃, the controller AP displays a fault alarm and immediately stops refrigeration to prevent the evaporator from freezing; if the coil temperature is higher than 3℃, the alarm is canceled. If the compressor stops working for more than 3 minutes, it is allowed to restart the refrigeration process The temperature sensor RT3 in the signal detection element is set on the compressor exhaust pipe. The temperature sensor RT3 senses the compressor exhaust temperature in real time, and the sample value is converted and input into the corresponding A / D channel of the controller AP. Through the software control logic, when the exhaust temperature exceeds 110℃, the compressor speed drops to 2000rpm and keeps running for 30s. There are three actions: if the exhaust temperature is still above 110℃, a fault alarm is triggered and the refrigeration shutdown process is executed. After the fault alarm, when the exhaust temperature returns to below 70℃, the alarm is eliminated. If the compressor stops for more than 3 minutes, the refrigeration process is allowed to start again; if the temperature exceeds 90℃, it continues to run at 2000rpm until the temperature is below 90℃ and the action is executed; if the exhaust temperature is below 90℃, the compressor speed is restored to the standard value.

[0037] The high-pressure pressure sensor YCQ1 and the low-pressure pressure sensor YCQ2 in the signal detection element are respectively arranged on the compressor exhaust pipe and the return air pipe. The sampling values ​​are converted and input into the corresponding A / D channels of the controller AP. Through the software control logic, when the system pressure sampled by YCQ1 exceeds 3.2Mpa or the system pressure sampled by YCQ2 is lower than 0.05Mpa, the controller AP displays a fault alarm and stops refrigeration immediately.

[0038] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. The embodiments described in the present invention are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction, and such combinations should also be regarded as the contents disclosed in the present disclosure as long as they do not violate the concept of the present invention. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0039] The present invention is not limited to the specific details of the above-mentioned embodiments. Within the scope of the technical concept of the present invention and without departing from the design concept of the present invention, various modifications and improvements made to the technical solution of the present invention by technical personnel in this field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A control system for a DC28V and DC600V dual-powered air conditioner, wherein the evaporating fan, condensing fan, compressor, and PTC electric heater in the dual-powered air conditioner are powered by a DC600V power supply, and the controller is powered by a DC28V power supply, characterized in that: Including signal detection components, compressor pre-charging components, control components, and protection components; The controller is electrically connected to the evaporation fan, condensation fan and compressor in the dual-power air conditioner; The signal detection element includes a temperature sensor and a pressure sensor, which are used to detect the temperature and pressure in the dual-powered air conditioner, and the signal detection element is electrically connected to the signal detection interface of the controller; The compressor pre-charging element includes a high-voltage connector and a pre-charging circuit, the control module of the compressor is connected to the DC600V power supply line through the high-voltage connector and the pre-charging circuit, and the compressor pre-charging element is electrically connected to the control signal interface of the controller; The control device includes multiple groups of high-voltage DC relays, the moving contacts are closed to connect the power supply ends of the evaporating fan, the condensing fan, the compressor, and the PTC electric heater to the DC600V power supply line, and the coils of each group of high-voltage DC relays are electrically connected to the control signal interface of the controller; The protection device includes two groups of high-voltage DC circuit breakers, wherein the main contacts of one group of high-voltage DC circuit breakers are connected to the evaporator fan and the DC600V power supply bus positive line, and the main contacts of the other group of high-voltage DC circuit breakers are connected to the condenser fan and the DC600V power supply bus positive line, and the auxiliary contacts of the two groups of high-voltage DC circuit breakers are respectively electrically connected to the overload signal detection port of the controller.

2. The control system of a DC28V and DC600V dual-powered air conditioner according to claim 1, characterized in that: The signal detection element includes three groups of temperature sensors, which are respectively used to detect the return air temperature, coil temperature and exhaust temperature in the dual-powered air conditioner; it also includes two groups of pressure sensors, which are respectively used to detect the high-pressure side pressure and the low-pressure side pressure of the refrigeration system in the dual-powered air conditioner. The three groups of temperature sensors and the two groups of pressure sensors are respectively electrically connected to the signal sampling port of the controller.

3. The control system of a DC28V and DC600V dual-powered air conditioner according to claim 1, characterized in that: The protection device also includes a temperature relay, and both ends of the break contact of the temperature relay are electrically connected to the overheat protection signal of the controller respectively.

4. The control system of a DC28V and DC600V dual-powered air conditioner according to claim 1, characterized in that: The protection device also includes multiple groups of high-voltage DC fuses, and each group of high-voltage DC fuses is respectively connected to the compressor pre-charge element, the PTC electric heater and the DC600V power supply bus positive line.

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