CN201974508U - AC/DC self-adaptive switch quantity acquisition circuit - Google Patents
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Abstract
一种交直流自适应的开关量采集电路，涉及电力自动化技术领域，所解决的是方便软件维护的同时，降低硬件成本的技术问题。该电路包括CPU、CPU侧电源、辅助电源、辅助电源信号输入回路及开关量信号输入回路；所述开关量信号输入回路包括一开关量隔离光耦、一开关量限流电阻、一开关量稳压管，及设于采集现场的一个开关量输出开关，用于采集开关量输出开关输出的开关量信号；所述辅助电源信号输入回路包括一辅助信号隔离光耦、一辅助信号限流电阻、一辅助信号稳压管，用于采集辅助电源输出的辅助信号；所述辅助信号限流电阻的阻值大于开关量限流电阻的阻值。本实用新型提供的采集电路，硬件成本低，软件维护方便。
An AC/DC self-adaptive switching value acquisition circuit relates to the technical field of electric power automation, and solves the technical problem of reducing hardware cost while facilitating software maintenance. The circuit includes a CPU, a power supply on the CPU side, an auxiliary power supply, an auxiliary power supply signal input circuit, and a switch signal input circuit; pressure tube, and a switching value output switch located at the collection site, used to collect switching value signals output by the switching value output switch; the auxiliary power signal input loop includes an auxiliary signal isolating optocoupler, an auxiliary signal current limiting resistor, An auxiliary signal regulator tube, used to collect the auxiliary signal output by the auxiliary power supply; the resistance value of the auxiliary signal current limiting resistor is greater than the resistance value of the switching value current limiting resistor. The acquisition circuit provided by the utility model has low hardware cost and convenient software maintenance.
Description
技术领域technical field
本实用新型涉及电力自动化技术，特别是涉及一种交直流自适应的开关量采集电路的技术。The utility model relates to electric power automation technology, in particular to a technology of an AC-DC self-adaptive switching quantity acquisition circuit.
背景技术Background technique
在电力自动化装置中，开关量采集的应用非常普遍。开关量的分、合状态采集必须借助辅助电源，辅助电源通常都是直接取自电力自动化装置中的电源。由于电力自动化装置中的电源有直流、交流之分，因此开关量采集所借助的辅助电源也有直流、交流之分，辅助电源为直流电源时，在开关合闸状态下所采集的开关量信号为恒定的高电平，辅助电源为交流电源时在开关合闸状态下所采集的开关量信号为脉冲信号。In electric power automation devices, the application of switching value acquisition is very common. The state acquisition of the switching value's opening and closing must rely on the auxiliary power supply, which is usually directly taken from the power supply in the electric automation device. Since the power supply in the electric automation device is divided into DC and AC, the auxiliary power source used for switch value collection is also divided into DC and AC. Constant high level, when the auxiliary power supply is an AC power supply, the switching signal collected in the state of switch closing is a pulse signal.
电力自动化装置为了适应两种不同的开关量信号，通常采取以下两种应对方式：1）设置两套软件处理方案，一套对应辅助电源为直流电源的开关量信号，另一套对应辅助电源为交流电源的开关量信号，这种方式需要同时维护两套程序，给软件维护带来了麻烦；2）在每一路辅助电源为交流电源的开关量信号采集回路中增加整流桥和滤波电容（参见图3），将所采集的脉冲信号整流、滤波成直流信号后供CPU采集，这种方式会导致硬件回路复杂、电路板面积增大，进而导致硬件成本增加。In order to adapt to two different switching signals, the electric automation device usually adopts the following two coping methods: 1) Set up two sets of software processing schemes, one set corresponds to the switching signal of the auxiliary power supply as DC power supply, and the other set corresponds to the auxiliary power supply as Switching signal of AC power supply, this method needs to maintain two sets of programs at the same time, which brings trouble to software maintenance; 2) Add rectifier bridge and filter capacitor in the switching signal acquisition circuit of each auxiliary power supply of AC power supply (see Figure 3), the collected pulse signal is rectified and filtered into a DC signal for the CPU to collect. This method will lead to a complex hardware circuit, an increase in the area of the circuit board, and an increase in hardware costs.
实用新型内容 Contents of utility model
针对上述现有技术中存在的缺陷，本实用新型所要解决的技术问题是提供一种电路结构简单，硬件成本低，软件维护方便的交直流自适应的开关量采集电路及其采集方法。Aiming at the above-mentioned defects in the prior art, the technical problem to be solved by the utility model is to provide an AC/DC self-adaptive switching value acquisition circuit and its acquisition method with simple circuit structure, low hardware cost and convenient software maintenance.
为了解决上述技术问题，本实用新型所提供的一种交直流自适应的开关量采集电路，包括CPU、CPU侧电源、辅助电源，及至少一路开关量信号输入回路，所述CPU设有至少一个开关量信号采集端，每个开关量信号采集端对应一路开关量信号输入回路，所述CPU侧电源接到CPU的电源接口，其特征在于：还包括一路辅助电源信号输入回路；In order to solve the above-mentioned technical problems, an AC/DC self-adaptive switching value acquisition circuit provided by the utility model includes a CPU, a CPU side power supply, an auxiliary power supply, and at least one switching value signal input circuit, and the CPU is provided with at least one Switch signal acquisition terminal, each switch signal acquisition terminal corresponds to one switch signal input loop, the CPU side power supply is connected to the power interface of the CPU, and it is characterized in that: it also includes one auxiliary power supply signal input loop;
所述开关量信号输入回路包括一开关量隔离光耦、一开关量限流电阻、一开关量稳压管，及设于采集现场的一个开关量输出开关，所述开关量隔离光耦的正、负信号输入端之间串接一开关量滤波电容，其正信号输入端依次串接开关量限流电阻、开关量稳压管、开关量输出开关到辅助电源的正电源输出端，其负信号输入端接到辅助电源的负电源输出端，其正信号输出端接CPU侧电源的正电源端，其负信号输出端经一开关量采样电阻接到CPU侧电源的地端；The switching value signal input loop includes a switching value isolating optocoupler, a switching value current limiting resistor, a switching value regulator tube, and a switching value output switch located at the collection site. , A switching value filter capacitor is connected in series between the negative signal input terminals, and its positive signal input terminal is sequentially connected in series with a switching value current limiting resistor, a switching value regulator tube, and a switching value output switch to the positive power output terminal of the auxiliary power supply. The signal input terminal is connected to the negative power output terminal of the auxiliary power supply, its positive signal output terminal is connected to the positive power supply terminal of the CPU side power supply, and its negative signal output terminal is connected to the ground terminal of the CPU side power supply through a switching value sampling resistor;
所述CPU的各开关量信号采集端分别接到各开关量信号输入回路中的开关量隔离光耦的负信号输出端；Each switching value signal acquisition end of the CPU is respectively connected to the negative signal output end of the switching value isolation optocoupler in each switching value signal input circuit;
所述辅助电源信号输入回路包括一辅助信号隔离光耦、一辅助信号限流电阻、一辅助信号稳压管，所述辅助信号隔离光耦的正、负信号输入端之间串接一辅助信号滤波电容，其正信号输入端依次串接辅助信号限流电阻、辅助信号稳压管到辅助电源的正电源输出端，其负信号输入端接到辅助电源的负电源输出端，其正信号输出端接CPU侧电源的正电源端，其负信号输出端经一辅助信号采样电阻接到CPU侧电源的地端；The auxiliary power signal input circuit includes an auxiliary signal isolation optocoupler, an auxiliary signal current limiting resistor, and an auxiliary signal voltage regulator tube, and an auxiliary signal is connected in series between the positive and negative signal input terminals of the auxiliary signal isolation optocoupler. Filter capacitor, its positive signal input terminal is connected in series with auxiliary signal current limiting resistor, auxiliary signal regulator tube to the positive power output terminal of the auxiliary power supply, its negative signal input terminal is connected to the negative power supply output terminal of the auxiliary power supply, and its positive signal output The terminal is connected to the positive power supply terminal of the CPU side power supply, and its negative signal output terminal is connected to the ground terminal of the CPU side power supply through an auxiliary signal sampling resistor;
所述CPU设有一个辅助信号采集端，该辅助信号采集端接到辅助电源信号输入回路中的辅助信号隔离光耦的负信号输出端；The CPU is provided with an auxiliary signal acquisition terminal, which is connected to the negative signal output terminal of the auxiliary signal isolation optocoupler in the auxiliary power supply signal input loop;
所述辅助信号限流电阻的阻值大于开关量限流电阻的阻值。The resistance value of the auxiliary signal current limiting resistor is greater than the resistance value of the switching value current limiting resistor.
本实用新型提供的交直流自适应的开关量采集电路，增加了一路辅助电源信号输入回路，CPU通过辅助电源信号输入回路采集辅助电源输出的辅助信号，再根据采集的辅助信号判断开关量信号的状态，由于辅助电源为直流电源时输出的辅助信号为恒定的高电平，而辅助电源为交流电源时开关量信号的电平转换要先于辅助信号，能确保开关量信号在采集时已转换至高电平，不受辅助电源类型的影响，仅需一套软件处理方案即可适应两种采用不同辅助电源的开关量信号，软件维护非常方便，而且电路硬件的成本也较低。The AC-DC self-adaptive switching quantity acquisition circuit provided by the utility model adds an auxiliary power supply signal input circuit, and the CPU collects the auxiliary signal output by the auxiliary power supply through the auxiliary power signal input circuit, and then judges the switching quantity signal according to the collected auxiliary signal. state, because the auxiliary signal output when the auxiliary power supply is a DC power supply is a constant high level, and when the auxiliary power supply is an AC power supply, the level conversion of the switching signal is prior to the auxiliary signal, which can ensure that the switching signal has been converted during acquisition High level, not affected by the type of auxiliary power supply, only one set of software processing scheme can adapt to two kinds of switching signals with different auxiliary power supplies, the software maintenance is very convenient, and the cost of circuit hardware is also low.
附图说明Description of drawings
图1是本实用新型实施例的交直流自适应的开关量采集电路的电路图；Fig. 1 is the circuit diagram of the switching value acquisition circuit of the AC-DC self-adaptation of the utility model embodiment;
图2是本实用新型实施例的交直流自适应的开关量采集电路中，辅助电源为交流电源的开关量信号及辅助信号的时序图；Fig. 2 is the sequence diagram of the switch signal and the auxiliary signal of the switch signal and the auxiliary signal of the auxiliary power supply in the AC-DC self-adaptive switching value acquisition circuit of the embodiment of the utility model;
图3是现有采用整流滤波方式处理辅助电源为交流电源的开关量信号的开关量采集电路的电路图。FIG. 3 is a circuit diagram of an existing switching value acquisition circuit that uses a rectification and filtering method to process a switching value signal whose auxiliary power source is an AC power source.
具体实施方式Detailed ways
以下结合附图说明对本实用新型的实施例作进一步详细描述，但本实施例并不用于限制本实用新型，凡是采用本实用新型的相似结构及其相似变化，均应列入本实用新型的保护范围。The embodiments of the present utility model are described in further detail below in conjunction with the accompanying drawings, but the present embodiments are not intended to limit the present utility model. All similar structures and similar changes of the utility model should be included in the protection of the utility model. scope.
本实用新型实施例所提供的一种交直流自适应的开关量采集电路，包括CPU（微处理器）、CPU侧电源、辅助电源，及至少一路开关量信号输入回路，所述CPU设有至少一个开关量信号采集端，每个开关量信号采集端对应一路开关量信号输入回路，所述CPU侧电源接到CPU的电源接口，其特征在于：还包括一路辅助电源信号输入回路；An AC/DC self-adaptive switching quantity acquisition circuit provided by the embodiment of the utility model includes a CPU (microprocessor), a CPU side power supply, an auxiliary power supply, and at least one switching quantity signal input circuit. The CPU is equipped with at least A switch signal acquisition terminal, each switch signal acquisition terminal corresponds to a switch signal input loop, the CPU side power supply is connected to the power interface of the CPU, and it is characterized in that: it also includes an auxiliary power supply signal input loop;
如图1所示（该图中仅示出了一路开关量信号输入回路），所述开关量信号输入回路包括一开关量隔离光耦E2、一开关量限流电阻R2、一开关量稳压管D2，及设于采集现场的一个开关量输出开关K2，所述开关量隔离光耦E2的正、负信号输入端之间串接一开关量滤波电容C3，其正信号输入端依次串接开关量限流电阻R2、开关量稳压管D2、开关量输出开关K2到辅助电源的正电源输出端ACL（DC+），其负信号输入端接到辅助电源的负电源输出端ACN（DC-），其正信号输出端接CPU侧电源的正电源端VCC，其负信号输出端经一开关量采样电阻R5接到CPU侧电源的地端；As shown in Figure 1 (only one switch signal input circuit is shown in the figure), the switch signal input circuit includes a switch value isolation optocoupler E2, a switch value current limiting resistor R2, a switch value regulator Tube D2, and a switching value output switch K2 located at the collection site, a switching value filter capacitor C3 is connected in series between the positive and negative signal input terminals of the switching value isolation optocoupler E2, and its positive signal input terminals are sequentially connected in series Switching value current limiting resistor R2, switching value regulator tube D2, switching value output switch K2 are connected to the positive power output terminal ACL (DC+) of the auxiliary power supply, and its negative signal input terminal is connected to the negative power output terminal ACN of the auxiliary power supply (DC- ), its positive signal output terminal is connected to the positive power supply terminal VCC of the CPU side power supply, and its negative signal output terminal is connected to the ground terminal of the CPU side power supply through a switching value sampling resistor R5;
所述CPU的各开关量信号采集端S2分别接到各开关量信号输入回路中的开关量隔离光耦E2的负信号输出端；Each switch signal acquisition terminal S2 of the CPU is respectively connected to the negative signal output terminal of the switch isolation optocoupler E2 in each switch signal input circuit;
所述辅助电源信号输入回路包括一辅助信号隔离光耦E3、一辅助信号限流电阻R3、一辅助信号稳压管D3，所述辅助信号隔离光耦E3的正、负信号输入端之间串接一辅助信号滤波电容C4，其正信号输入端依次串接辅助信号限流电阻R3、辅助信号稳压管D3到辅助电源的正电源输出端ACL（DC+），其负信号输入端接到辅助电源的负电源输出端ACN（DC-），其正信号输出端接CPU侧电源的正电源端VCC，其负信号输出端经一辅助信号采样电阻R6接到CPU侧电源的地端；The auxiliary power signal input loop includes an auxiliary signal isolation optocoupler E3, an auxiliary signal current limiting resistor R3, and an auxiliary signal voltage regulator tube D3, and the positive and negative signal input terminals of the auxiliary signal isolation optocoupler E3 are connected in series Connect an auxiliary signal filter capacitor C4, its positive signal input terminal is connected in series with the auxiliary signal current limiting resistor R3, the auxiliary signal regulator tube D3 to the positive power output terminal ACL (DC+) of the auxiliary power supply, and its negative signal input terminal is connected to the auxiliary power supply The negative power supply output terminal ACN (DC-) of the power supply, its positive signal output terminal is connected to the positive power supply terminal VCC of the CPU side power supply, and its negative signal output terminal is connected to the ground terminal of the CPU side power supply through an auxiliary signal sampling resistor R6;
所述CPU设有一个辅助信号采集端S3，该辅助信号采集端S3接到辅助电源信号输入回路中的辅助信号隔离光耦E3的负信号输出端；The CPU is provided with an auxiliary signal acquisition terminal S3, which is connected to the negative signal output terminal of the auxiliary signal isolation optocoupler E3 in the auxiliary power supply signal input loop;
所述辅助信号限流电阻R3的阻值大于开关量限流电阻R2的阻值。The resistance value of the auxiliary signal current limiting resistor R3 is greater than the resistance value of the switching value current limiting resistor R2.
本实用新型实施例所提供的交直流自适应的开关量采集电路的采集方法，其特征在于：CPU通过辅助电源信号输入回路实时采集辅助电源输出的辅助信号，如果辅助信号为高电平，则通过各开关量信号输入回路实时采集各开关量输出开关输出的开关量信号，并检测所采集的各开关量信号的状态。The acquisition method of the AC/DC self-adaptive switching value acquisition circuit provided by the embodiment of the utility model is characterized in that: the CPU collects the auxiliary signal output by the auxiliary power supply in real time through the auxiliary power supply signal input circuit, if the auxiliary signal is high level, then The switching signal output by each switching value output switch is collected in real time through each switching value signal input circuit, and the state of each switching value signal collected is detected.
图2是本实用新型实施例的交直流自适应的开关量采集电路中，辅助电源为交流电源的开关量信号及辅助信号的时序图，该图中的11为开关量输出开关处于分状态时输出的开关量信号的时序，该图中的12为开关量输出开关处于合状态时输出的开关量信号的时序，该图中的22为辅助电源输出的辅助信号的时序；Fig. 2 is the sequence diagram of the switching value signal and the auxiliary signal of the auxiliary power supply being the switching value signal of the AC power supply in the AC-DC self-adaptive switching value acquisition circuit of the embodiment of the utility model, and 11 in this figure is when the switching value output switch is in the divided state The timing of the output switching signal, 12 in the figure is the timing of the switching signal output when the switching output switch is in the closed state, and 22 in the figure is the timing of the auxiliary signal output by the auxiliary power supply;
如图2所示，当辅助电源为交流电源时，CPU采集的辅助信号及开关量信号均为脉冲信号，由于辅助信号限流电阻的阻值大于开关量限流电阻的阻值，因此在辅助信号进行电平转换时，开关量信号的电平已先行转换。As shown in Figure 2, when the auxiliary power supply is an AC power supply, the auxiliary signal and switch signal collected by the CPU are all pulse signals. Since the resistance of the auxiliary signal current-limiting resistor is greater than the resistance of the switch When the signal undergoes level conversion, the level of the switching signal has been converted first.
当辅助电源为直流电源时，由于辅助电源输出的辅助信号为恒定的高电平，因此对开关量信号的采集没有任何影响。When the auxiliary power supply is a DC power supply, since the auxiliary signal output by the auxiliary power supply is a constant high level, it has no effect on the acquisition of the switching signal.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102169163A (en) * | 2010-12-30 | 2011-08-31 | 上海申瑞电力科技股份有限公司 | Alternating-current direct-current adaptive switching value collecting circuit and method |
| CN109188989A (en) * | 2018-11-07 | 2019-01-11 | 紫光测控有限公司 | One kind is opened into acquisition 110V220V Adaptable System |
| WO2022041890A1 (en) * | 2020-08-24 | 2022-03-03 | 南京磐能电力科技股份有限公司 | Switching value acquisition circuit and method |
| CN118777929A (en) * | 2024-09-09 | 2024-10-15 | 中国铁路设计集团有限公司 | Self-adaptive circuit and detection method for switch quantity of secondary equipment in traction power supply system |
-
2010
- 2010-12-30 CN CN 201020690999 patent/CN201974508U/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102169163A (en) * | 2010-12-30 | 2011-08-31 | 上海申瑞电力科技股份有限公司 | Alternating-current direct-current adaptive switching value collecting circuit and method |
| CN109188989A (en) * | 2018-11-07 | 2019-01-11 | 紫光测控有限公司 | One kind is opened into acquisition 110V220V Adaptable System |
| CN109188989B (en) * | 2018-11-07 | 2021-06-01 | 紫光测控有限公司 | Open-in acquisition 110V220V self-adaptive system |
| WO2022041890A1 (en) * | 2020-08-24 | 2022-03-03 | 南京磐能电力科技股份有限公司 | Switching value acquisition circuit and method |
| CN118777929A (en) * | 2024-09-09 | 2024-10-15 | 中国铁路设计集团有限公司 | Self-adaptive circuit and detection method for switch quantity of secondary equipment in traction power supply system |
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Owner name: SHANGHAI SUNRISE PROTECTIVE RELAY ELECTRIC CO.,LTD Free format text: FORMER OWNER: SHANGHAI SUNRISE POWER AUTOMATION CO., LTD. Effective date: 20130222 |
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