CN202276182U - Intelligent power supply apparatus used for building intercommunication system - Google Patents

本实用新型公开了一种用于楼宇对讲系统的智能电源装置，要解决的技术问题是当市电供电中断时，合理分配系统备用电池的用途，充分提高备用电池的利用率；在市电正常供电时，对该装置输出功耗进行智能管理。该装置包括连接室内机和计算机楼宇管理中心的系统总线及外接备用电池，还包括开关电源模块、DC/DC电路、供电检测电路、电池电压检测电路、单片机电路和SCS收发码电路。本实用新型是在普通电源系统的基础上当市电断电时，使系统工作在省电模式下，大大延长了备用电源的续电时间。在市电未停电时，可以降低电源装置开启自动保护功能(停止输出电流)的概率，或者降低处于极限工作状态的概率，以延长电源装置的使用寿命。

The utility model discloses an intelligent power supply device for a building intercom system. The technical problem to be solved is to reasonably allocate the use of the backup battery of the system when the mains power supply is interrupted, and fully improve the utilization rate of the backup battery; When the power supply is normal, the output power consumption of the device is intelligently managed. The device includes a system bus connecting the indoor unit and the computer building management center and an external backup battery, and also includes a switching power supply module, a DC/DC circuit, a power supply detection circuit, a battery voltage detection circuit, a single-chip circuit and an SCS code receiving and receiving circuit. The utility model makes the system work in the power-saving mode on the basis of the common power supply system when the mains power is cut off, and greatly prolongs the battery life of the backup power supply. When the mains power supply is not interrupted, the probability of the power supply device turning on the automatic protection function (stopping the output current) or the probability of being in the limit working state can be reduced, so as to prolong the service life of the power supply device.

用于楼宇对讲系统的智能电源装置Intelligent power supply unit for building intercom system

技术领域 technical field

本实用新型涉及一种为楼宇对讲系统提供电源的装置，特别涉及一种在交流断电的情况下，为其提供稳定、持续的直流电源的装置。The utility model relates to a device for providing a power supply for a building intercom system, in particular to a device for providing a stable and continuous DC power supply in the case of an AC power failure.

背景技术 Background technique

目前楼宇对讲系统种类越来越多，功能越来越强大，技术越来越先进，但它们的电源并没有多大突破。此类电源由于没有内置控制器，也没有和系统其它设备建立数据传输的功能。当市电(220V交流电)供电中断时，系统仍采用常规的供电方式，使用备用电池为系统中的用电设施供电，常常导致备用电池的电能很快耗尽，基本的呼叫开锁功能因为无电没法使用，如果此时正巧发生警情，对讲系统就因无电而起不到报警的作用。另外，该类电源没有设置当系统内负载功率突然增大时的应对机制，诸如多个小门口机同时呼叫各自的室内机(室内机都会打开视频)等即时性高负载情况，会使电源的输出电流陡然增大。一方面，如果电流超过了电源装置的最大输出电流，装置的保险器件会断开，电源就必须更换保险器件才能继续使用；另一方面，如果电流没有超过最大值，但略小于最大输出电流，电源装置在这样高负载的情况下长时间工作会影响自身的使用寿命。At present, there are more and more types of building intercom systems, more and more powerful functions, and more and more advanced technologies, but their power supply has not made much breakthrough. Since this type of power supply does not have a built-in controller, it does not have the function of establishing data transmission with other devices in the system. When the mains (220V AC) power supply is interrupted, the system still adopts the conventional power supply method, and uses the backup battery to supply power to the electrical facilities in the system, which often causes the power of the backup battery to be exhausted quickly. Unable to use, if the alarm happens to happen at this time, the intercom system will not be able to call the police because of no electricity. In addition, this type of power supply is not equipped with a response mechanism when the load power in the system suddenly increases. For example, when multiple small outdoor units call their respective indoor units at the same time (the indoor units will all turn on the video) and other instantaneous high load conditions, the power supply will be damaged. The output current increases suddenly. On the one hand, if the current exceeds the maximum output current of the power supply device, the fuse device of the device will be disconnected, and the power supply must be replaced to continue to use the fuse device; on the other hand, if the current does not exceed the maximum value, but slightly less than the maximum output current, The long-term work of the power supply unit under such a high load will affect its own service life.

发明内容 Contents of the invention

本实用新型的目的是提供一种用于楼宇对讲系统的智能电源装置，要解决的技术问题，一是当市电对所述系统供电中断时，合理分配系统备用电池的用途，充分提高备用电池的利用率；二是在市电正常供电时，对装置输出功耗进行智能管理。The purpose of this utility model is to provide an intelligent power supply device for building intercom systems. The technical problems to be solved are: first, when the mains power supply to the system is interrupted, the use of the backup battery of the system is reasonably allocated, and the backup battery is fully improved. The utilization rate of the battery; the second is to intelligently manage the output power consumption of the device when the mains power supply is normal.

本实用新型采用的技术方案为：The technical scheme that the utility model adopts is:

本实用新型的用于楼宇对讲系统的智能电源装置，包括连接室内机和计算机楼宇管理中心的系统总线及外接备用电池，该装置还包括开关电源模块、DC/DC电路、供电检测电路、电池电压检测电路、单片机电路和SCS收发码电路，其中：The intelligent power supply device used in the building intercom system of the utility model includes a system bus connecting the indoor unit and the computer building management center and an external backup battery. The device also includes a switching power supply module, a DC/DC circuit, a power supply detection circuit, and a battery. Voltage detection circuit, single-chip microcomputer circuit and SCS code sending and receiving circuit, wherein:

1)开关电源模块，将220V交流电转换为直流电压输出；1) Switching power supply module, which converts 220V AC power into DC voltage output;

2)DC/DC电路，将开关电源模块输出的直流电压经滤波、恒流、稳压后转换为设定电压值，输送至所述的系统总线；2) a DC/DC circuit, which converts the DC voltage output by the switching power supply module into a set voltage value after filtering, constant current, and voltage stabilization, and transmits it to the system bus;

3)供电检测电路，对开关电源模块输出的直流电压值进行取样、检测、判断，并将判断结果以高电平或低电平的方式输送给单片机电路；3) The power supply detection circuit samples, detects and judges the DC voltage value output by the switching power supply module, and sends the judgment result to the single-chip microcomputer circuit in the form of high level or low level;

4)电池电压检测电路，对电池电压进行取样、检测，并将采集到的取样电压发送给单片机电路。4) The battery voltage detection circuit samples and detects the battery voltage, and sends the collected sampling voltage to the single-chip circuit.

5)单片机电路，接收所述的高低电平信号和取样电压，向SCS收发码电路下发指令；5) the single-chip microcomputer circuit receives the high and low level signals and the sampling voltage, and sends instructions to the SCS transceiver circuit;

6)SCS收发码电路，根据单片机电路下达的指令，向所述的系统总线传输控制命令或指导信息。6) The SCS transceiver circuit transmits control commands or guidance information to the system bus according to the instructions issued by the single-chip microcomputer circuit.

本实用新型还包括电流检测电路，该电路输入端接于电源装置输出电流的主干线上，其输出端与所述的单片机电路的一个输入端相接，其作用是检测电源装置输出主干线上的实时电流值。The utility model also includes a current detection circuit, the input terminal of which is connected to the main line of the output current of the power supply device, and its output terminal is connected to an input terminal of the single-chip microcomputer circuit, and its function is to detect the output on the main line of the power supply device. real-time current value.

所述的开关电源模块的直流输出电压为31.5V。The DC output voltage of the switching power supply module is 31.5V.

所述的DC/DC电路直流输出电压为30V。The DC output voltage of the DC/DC circuit is 30V.

所述的外接备用电池额定电压为24V，其输出端接于所述的开关电源模块，并在交流断电时，由开关电源模块切换至DC/DC电路的输入端。The rated voltage of the external backup battery is 24V, and its output terminal is connected to the switching power supply module, and is switched to the input terminal of the DC/DC circuit by the switching power supply module when the AC power is cut off.

在所述的室内机中设有视频驱动电路开启和关闭的控制电路，该电路受室内机的单片机控制，而单片机可与室内机的SCS收发码电路相连，SCS收发码电路负责接收来自系统总线的指令。The indoor unit is provided with a control circuit for opening and closing the video drive circuit. The circuit is controlled by the single-chip microcomputer of the indoor unit, and the single-chip microcomputer can be connected with the SCS transceiver code circuit of the indoor unit. The SCS transceiver code circuit is responsible for receiving data from the system bus. instructions.

与现有技术相比，本实用新型是在普通电源系统的基础上，增设了供电检测电路、电池电压检测电路、电流检测电路、SCS信号收发码电路和单片机电路，从而将电源装置与系统总线建立了连接，使电源装置能够与系统总线中的其它设施进行通讯、传输数据。当市电断电时，使系统工作在省电模式下，大大延长了备用电源的续电时间。更为重要的是，当小区供电系统(市电)遭遇恶意人为因素、火灾等外力破坏时，室内机的安防设施还能在较长时间内持续、有效地工作，保护了小区住户的生命财产安全。而在市电未停电时，可以通过控制室内机的工作模式起到降低电源装置开启自动保护功能(停止输出电流)的概率，或者降低处于极限工作状态的概率，以延长电源装置的使用寿命。Compared with the prior art, the utility model adds a power supply detection circuit, a battery voltage detection circuit, a current detection circuit, an SCS signal sending and receiving code circuit and a single-chip microcomputer circuit on the basis of an ordinary power supply system, thereby connecting the power supply device with the system bus A connection is established that enables the power supply unit to communicate and transfer data with other facilities on the system bus. When the mains power is cut off, the system works in the power saving mode, which greatly prolongs the battery life of the backup power supply. More importantly, when the community power supply system (mains power) is damaged by malicious human factors, fire and other external forces, the security facilities of the indoor unit can continue to work effectively for a long time, protecting the lives and properties of the residents of the community Safety. And when the mains power is not cut off, the probability of turning on the automatic protection function (stopping the output current) of the power supply device can be reduced by controlling the working mode of the indoor unit, or the probability of being in the limit working state can be reduced, so as to prolong the service life of the power supply device.

附图说明 Description of drawings

图1是本实用新型的电路框图。Fig. 1 is a circuit block diagram of the utility model.

图2是本实用新型供电检测电路图。Fig. 2 is a power supply detection circuit diagram of the utility model.

图3是本实用新型电池电压检测电路图。Fig. 3 is a circuit diagram of the battery voltage detection of the utility model.

图4是本实用新型电流检测电路图。Fig. 4 is a circuit diagram of the current detection circuit of the utility model.

具体实施方式 Detailed ways

下面结合附图和实施例对本实用新型作进一步详细说明。Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail.

本实用新型开创性的采用单片机电路对电源电路进行检测、管理，并使用SCS(差分数字传输技术)收发码电路通过由室外机、室内机、中间连接设施和计算机楼宇管理中心(以下简称管理中心)组成的系统总线与该系统内的其它设施进行通讯、传输数据。The utility model groundbreakingly adopts the single-chip microcomputer circuit to detect and manage the power supply circuit, and uses the SCS (differential digital transmission technology) transceiver code circuit to pass through the outdoor unit, indoor unit, intermediate connection facilities and computer building management center (hereinafter referred to as the management center) ) to communicate with other facilities in the system and transmit data.

本实用新型还包括开关电源模块、DC/DC电路、供电检测电路、单片机检测电路、SCS收发码电路、电流检测电路、电池电压检测电路以及外接备用电池，其中，外接备用电池的输出端和交流市电分别接入开关电源模块，开关电源模块的输出端接往DC/DC电路的输入端，DC/DC电路的输出端接往所述的系统中各用电设施，供电检测电路的输入端与开关电源模块的输出端相接，其输出端接于单片机电路，单片机电路的输出端接入SCS收发码电路的输入端，SCS收发码电路的输出端通过系统总线接往所述的系统内的其它设施，电流检测电路的输入端接于电源装置输出电流的主干线上，其输出端接于单片机电路的输入端，电池电压检测电路接于外接备用电池与单片机电路之间。The utility model also includes a switching power supply module, a DC/DC circuit, a power supply detection circuit, a single-chip microcomputer detection circuit, an SCS code sending and receiving circuit, a current detection circuit, a battery voltage detection circuit and an external backup battery, wherein the output terminal of the external backup battery and the AC Mains power is respectively connected to the switching power supply module, the output terminal of the switching power supply module is connected to the input terminal of the DC/DC circuit, the output terminal of the DC/DC circuit is connected to each power consumption facility in the system, and the input terminal of the power supply detection circuit It is connected to the output terminal of the switching power supply module, and its output terminal is connected to the single-chip microcomputer circuit. The output terminal of the single-chip microcomputer circuit is connected to the input terminal of the SCS code receiving and receiving circuit, and the output terminal of the SCS code receiving and receiving circuit is connected to the system through the system bus. For other facilities, the input terminal of the current detection circuit is connected to the main line of the output current of the power supply device, the output terminal is connected to the input terminal of the single-chip circuit, and the battery voltage detection circuit is connected between the external backup battery and the single-chip circuit.

本实用新型的技术方案具有以下两大功能：The technical solution of the utility model has the following two major functions:

1)备用电池省电管理功能：如图1所示，本实用新型由220V交流市电供电，市电经本实用新型的开关电源模块转换为31.5V直流电压，然后再经过DC/DC电路转换为30V直流电压由装置的各端口输出。外接24V备用电池的输出端接入开关电源模块中，平时备用电池处于充电状态。当市电停电时，由开关电源模块切换为备用电池电压输出状态，输出的24V电压通过DC/DC电路升压为30V直流电压再由装置各端口输出。电路中有一供电检测电路，用于检测开关电源输出的电压值。当电压从直流31.5V变为24V时(即交流市电断电，由外接备用电池供电时)，该检测电路输出低电平给单片机(请参阅图2)。单片机发出指令，通过SCS收发码电路和系统总线传输给系统内的室内机和管理中心。室内机转换为省电模式，即室内机被呼叫时不再开启视频驱动电路；管理中心的电池管理界面中，对应的电池图标由“有电，电池满格”切换为“停电，电池满格”。在市电正常供电和停电时，单片机通过电池电压检测电路采集电池输出端的电压(请参阅图3)。当停电后，系统消耗电池的电能，电池的电量逐渐下降，单片机会将电池剩余50％的电量、剩余20％的电量两个状态信息通过SCS收发码电路和系统总线传输给管理中心，管理中心的电池管理界面中，对应的电池图标分别切换为“停电，电池50％电量”、“停电，电池20％电量”。这样，系统能够节约电能以延长各设施的正常工作，保证在出现警情时，系统的安防设备(如探头触发、室内机上报警情给管理中心等设备)不会因无电而停止工作；根据电池状态的显示情况，管理人员在基本可以预知的有限时间内及时处理停电问题，保证对讲系统的连续工作。1) Backup battery power-saving management function: as shown in Figure 1, the utility model is powered by 220V AC mains power, which is converted into 31.5V DC voltage by the switching power supply module of the utility model, and then converted by a DC/DC circuit The 30V DC voltage is output from each port of the device. The output end of the external 24V backup battery is connected to the switching power supply module, and the backup battery is usually in a charging state. When the mains power fails, the switching power supply module switches to the backup battery voltage output state, and the output 24V voltage is boosted to 30V DC voltage by the DC/DC circuit and then output by each port of the device. There is a power supply detection circuit in the circuit, which is used to detect the voltage value output by the switching power supply. When the voltage changes from DC 31.5V to 24V (that is, when the AC power supply is cut off and powered by an external backup battery), the detection circuit outputs a low level to the microcontroller (see Figure 2). The single-chip microcomputer sends instructions, which are transmitted to the indoor units and the management center in the system through the SCS transceiver circuit and the system bus. The indoor unit switches to power-saving mode, that is, the video drive circuit is no longer turned on when the indoor unit is called; in the battery management interface of the management center, the corresponding battery icon is switched from "power on, full battery" to "power off, full battery ". During the normal power supply and power failure of the mains, the single-chip microcomputer collects the voltage of the battery output terminal through the battery voltage detection circuit (see Figure 3). When the power is cut off, the system consumes the battery power, and the battery power gradually decreases. The single-chip computer will transmit the two state information of the remaining 50% power and the remaining 20% power of the battery to the management center through the SCS transceiver circuit and the system bus. In the battery management interface of , the corresponding battery icons are switched to "Power failure, battery 50% power" and "Power failure, battery 20% power". In this way, the system can save power to prolong the normal work of each facility, ensuring that when an alarm occurs, the security equipment of the system (such as triggering the probe, sending the alarm on the indoor unit to the management center, etc.) will not stop working due to lack of power; according to The status of the battery is displayed, and the management personnel can deal with the power failure problem in a limited time that is basically predictable, so as to ensure the continuous operation of the intercom system.

供电检测电路的工作原理：The working principle of the power supply detection circuit:

如图2所示，第5稳压管DZ5负极连接到开关电源直流输出端，当本实用新型由市电供电时，第5稳压管DZ5负极为31.5V，31.5V经其稳压后降压为4.5V，该电压使第十一晶体管TR11导通，第十一晶体管TR11集电极电平被拉低，第二发光二极管LED2的绿色灯点亮，表示交流供电；同时单片机供电检测端口检测到该低电平状态，判定此时为交流供电，于是对室内机发送市电供电模式指令。As shown in Fig. 2, the negative pole of the fifth voltage regulator tube DZ5 is connected to the DC output terminal of the switching power supply. The voltage is 4.5V, which turns on the eleventh transistor TR11, the collector level of the eleventh transistor TR11 is pulled down, and the green light of the second light-emitting diode LED2 lights up, indicating AC power supply; at the same time, the single-chip power supply detection port detects When it reaches the low level state, it is determined that the AC power supply is at this time, and then a commercial power supply mode command is sent to the indoor unit.

当市电停电后，第5稳压管DZ5负极为外接备用电池的输出电压24V，第5稳压管DZ5不导通，第十一晶体管TR11基极因无电压而截止，其集电极为高电平，第二发光二极管LED2的绿色灯熄灭；同时单片机供电检测端口检测到该高电平状态，判定此时为外接备用电池供电，因而通过SCS收发码电路对系统内的室内机发送省电模式指令；由于第十五晶体管TR15基极因无电压而截止，其集电极电压置高，使得第十六晶体管TR16导通，其集电极电平拉低，第二发光二极管LED2的红色灯点亮，表示市电停电。When the mains power fails, the negative pole of the fifth regulator DZ5 is the output voltage of the external backup battery 24V, the fifth regulator DZ5 is not turned on, the base of the eleventh transistor TR11 is cut off due to no voltage, and its collector is high Level, the green light of the second light-emitting diode LED2 goes out; at the same time, the power supply detection port of the single-chip microcomputer detects the high level state, and it is judged that it is powered by an external backup battery at this time. Mode instruction; since the base of the fifteenth transistor TR15 is cut off due to no voltage, its collector voltage is set high, so that the sixteenth transistor TR16 is turned on, its collector level is pulled down, and the red light point of the second light-emitting diode LED2 Lights up, indicating that the utility power is out of power.

电池电压检测电路的工作原理：The working principle of the battery voltage detection circuit:

如图3所示，第九十三电阻R93和第九十四电阻R94对电池电压进行分压，单片机ADC端口采集第九十四电阻R94的电压降——电池电压检测电压。第一稳压管ZD1的负极接电池电压，电池电压经第一稳压管ZD1降压、第七十四电阻R74和第七十五电阻R75分压。市电正常供电时，开关电源会给电池充电，此时的“电池电压”实际是充电电压-27.6V。27.6V经降压、分压后，在第十三晶体管TR13的基极处产生约1.23V的电压，于是第十三晶体管TR13导通，将第十七晶体管TR17的基极电压拉低，第十七晶体管TR17截止，第一发光二极管LED1不点亮。市电停电时，备用电池电量逐渐被消耗，当电压下降到低于23V时，电池电压经降压、分压后，在第十三晶体管TR13的基极处产生的压降低于晶体管PN结导通电压0.7V，于是第十三晶体管TR13截止，第十七晶体管TR17的基极电压上升为5V，第十七晶体管TR17导通，第一发光二极管LED1点亮，表示电池欠压。As shown in FIG. 3 , the ninety-third resistor R93 and the ninety-fourth resistor R94 divide the battery voltage, and the single-chip ADC port collects the voltage drop of the ninety-fourth resistor R94—the battery voltage detection voltage. The negative pole of the first voltage regulator tube ZD1 is connected to the battery voltage, and the battery voltage is stepped down by the first voltage regulator tube ZD1 and divided by the seventy-fourth resistor R74 and the seventy-fifth resistor R75. When the mains power supply is normal, the switching power supply will charge the battery, and the "battery voltage" at this time is actually the charging voltage -27.6V. After the 27.6V is stepped down and divided, a voltage of about 1.23V is generated at the base of the thirteenth transistor TR13, so the thirteenth transistor TR13 is turned on, and the base voltage of the seventeenth transistor TR17 is pulled down. The seventeenth transistor TR17 is turned off, and the first light-emitting diode LED1 is not lit. When the mains power fails, the power of the backup battery is gradually consumed. When the voltage drops below 23V, after the battery voltage is stepped down and divided, the voltage drop generated at the base of the thirteenth transistor TR13 is lower than that of the PN junction of the transistor. The voltage is 0.7V, so the thirteenth transistor TR13 is turned off, the base voltage of the seventeenth transistor TR17 rises to 5V, the seventeenth transistor TR17 is turned on, and the first light-emitting diode LED1 lights up, indicating that the battery is undervoltage.

通过本实用新型供电检测电路和电池电压检测电路的检测，不管是市电正常供电，或者市电停电，装置的面板上会有状态指示，同时装置还会将系统的供电和用电状况通过系统总线发送给管理中心，这样方便管理中心科学管理整个系统的电源使用情况。Through the detection of the power supply detection circuit and the battery voltage detection circuit of the utility model, no matter whether the mains power supply is normal or the mains power is cut off, there will be a status indication on the panel of the device, and the device will also pass the power supply and power consumption status of the system through the system The bus is sent to the management center, which is convenient for the management center to scientifically manage the power usage of the entire system.

2)电源功率智能分配功能：2) Intelligent power distribution function:

如所述系统内的室内机分别连接有小门口机，小门口机是从室内机取电工作的。在220V交流正常供电的情况下，若遇到多台小门口机同时呼叫各自对应的室内机时，室内机都打开各自的显示屏并响铃声，这种情况易使系统内电源负载超负荷，此种情况下，极易造成电源装置30V直流输出主干线上的自恢复保险丝断路，影响系统的正常工作(自恢复保险丝再次恢复通路需要一定时间，从十几秒到1分钟不等)。本实用新型可以避免上述情况的发生。For example, the indoor units in the system are respectively connected with small outdoor stations, and the small outdoor stations are powered by the indoor units. In the case of normal 220V AC power supply, if multiple small VTOs call their corresponding indoor units at the same time, the indoor units will turn on their respective display screens and ring tones. This situation will easily overload the power supply in the system. In this case, it is very easy to cause the self-recovery fuse on the 30V DC output main line of the power supply unit to break, which will affect the normal operation of the system (it will take a certain time for the self-recovery fuse to restore the circuit again, ranging from more than ten seconds to one minute). The utility model can avoid the generation of above-mentioned situation.

本实用新型的电流检测电路针对装置内30V直流输出主干线上的即时电流进行检测，通过对该即时电流大小的判断，来确定系统用电情况是否正常，该电路将输出总电流以电压的形式反馈给单片机ADC口，单片机根据该电压的高低判断系统用电是否满载，并将装置的电流输出数据通过SCS收发码电路和系统总线发送指令给系统内的室内机，室内机的单片机由此判断当小门口机呼叫时是否打开其视频驱动电路显示视频。The current detection circuit of the utility model detects the real-time current on the 30V DC output main line in the device, and determines whether the power consumption of the system is normal by judging the magnitude of the real-time current, and the circuit outputs the total current in the form of voltage Feedback to the ADC port of the single-chip microcomputer, the single-chip microcomputer judges whether the system is fully loaded according to the level of the voltage, and sends the current output data of the device to the indoor unit in the system through the SCS transceiver circuit and the system bus, and the single-chip microcomputer of the indoor unit judges accordingly Whether to turn on its video drive circuit to display video when the small door phone calls.

电流检测电路的工作原理：The working principle of the current detection circuit:

如图4所示，当电流经过串联在电源装置输出主干线上的第一百零八电阻R108和第二十二电阻R22时，在它们两端产生压降。由于该装置输出电流的范围为0～2A，根据欧姆定律可以计算出第一百零八电阻R108、第二十二电阻R22两端的电压变化范围为0～0.1V，第3芯片U3检测后从第1脚输出0～2.05V的电池检测电压到单片机的ADC端口。单片机的ADC端口从采集到的电压计算出当前DC/DC电路输出的电流值，然后将电源数据通过SCS信号收发码电路和系统总线发送给室内机，室内机根据电源数据决定其连接的小门口机呼叫它时是否开启视频驱动电路，从而降低了电源的功耗，节能的同时也延长了它的使用寿命。As shown in FIG. 4, when the current passes through the 108th resistor R108 and the 22nd resistor R22 connected in series on the output main line of the power supply device, a voltage drop occurs across them. Since the output current range of the device is 0-2A, according to Ohm's law, it can be calculated that the voltage variation range of the 108th resistor R108 and the 22nd resistor R22 is 0-0.1V. Pin 1 outputs the battery detection voltage of 0-2.05V to the ADC port of the microcontroller. The ADC port of the single-chip computer calculates the current value output by the current DC/DC circuit from the collected voltage, and then sends the power data to the indoor unit through the SCS signal transceiver circuit and the system bus, and the indoor unit determines the small door it is connected to according to the power data Whether to turn on the video drive circuit when the machine calls it, thereby reducing the power consumption of the power supply, saving energy and prolonging its service life.