CN215871182U - Three-phase power grid three-phase output port anti-interference circuit and electrical equipment - Google Patents
Three-phase power grid three-phase output port anti-interference circuit and electrical equipment Download PDFInfo
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- CN215871182U CN215871182U CN202121433762.2U CN202121433762U CN215871182U CN 215871182 U CN215871182 U CN 215871182U CN 202121433762 U CN202121433762 U CN 202121433762U CN 215871182 U CN215871182 U CN 215871182U
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Abstract
The application discloses three-phase electric wire netting three-phase output port anti jamming circuit and electrical equipment, anti jamming circuit includes: the three-phase filter circuit is used for filtering or buffering current at the moment of electrifying, one end of the three-phase filter circuit is connected with a three-phase output port of a three-phase power grid, and the other end of the three-phase filter circuit is grounded; the signal processing circuit is connected with the input end of the signal port and outputs the signal accessed by the signal port after filtering and amplifying; the control circuit is connected with the signal processing circuit and used for comparing the parameter of the signal with the preset range of the reference parameter and outputting a driving signal according to the comparison result; and the intelligent switch circuit is connected with the three-phase filter circuit and the control circuit and is used for controlling the filter capacitor bank to be directly grounded or grounded through the first resistor according to the driving signal. According to the scheme, the filter capacitor bank can be controlled to be directly grounded or grounded through the first resistor according to whether the parameter of the received signal is abnormal or not, the stability and the electromagnetic compatibility of the system are improved, and the labor cost or the material cost is reduced.
Description
Technical Field
The application belongs to the technical field of electronics, especially relates to a three-phase electric wire netting three-phase output port anti jamming circuit and electrical equipment.
Background
In order to meet CE certification for compatibility with domestic and foreign markets, most frequency converters on the market are added with Y capacitors at the output ports of a three-phase power grid in a micro-farad level generally. If the Y capacitor at this position is effective, in a frequency converter application system with a leakage switch, the leakage switch is often tripped instantaneously, so that most manufacturers connect a jumper switch in series at the Y capacitor and default to be turned off when leaving a factory.
However, the existing frequency converter signal ports (such as an analog quantity signal port and a 485 communication signal port) are easily interfered under the condition of severe environment (such as strong and weak electric near-field coupling and poor system grounding), and the system works abnormally. At present, a common method is that service personnel carry out on-site short circuit on a jumper switch, or common mode inductors, isolation circuits and the like with higher cost are added at a signal port of a frequency converter, so that the labor cost or the material cost is increased, and the product competitiveness is reduced.
SUMMERY OF THE UTILITY MODEL
The application aims to provide an anti-jamming circuit of a three-phase power grid three-phase output port and electrical equipment, and aims to solve the problem that a traditional anti-jamming scheme is difficult to enable a system to simultaneously meet electromagnetic compatibility and stability and the problem that labor cost or material cost is high.
The first aspect of the embodiment of the present application provides a three-phase electric wire netting three-phase output port anti jamming circuit, includes:
the three-phase filter circuit comprises a filter capacitor bank and a first resistor, one end of the three-phase filter circuit is connected with a three-phase output port of the three-phase power grid, and the other end of the three-phase filter circuit is grounded;
the signal processing circuit is connected with the input end of the signal port and outputs the signal accessed by the signal port after filtering and amplifying;
the control circuit is connected with the signal processing circuit and used for comparing the parameters of the filtered and amplified signals with a preset range of reference parameters and outputting corresponding driving signals according to a comparison result;
and the intelligent switch circuit is connected with the three-phase filter circuit and the control circuit and is used for controlling the filter capacitor bank to be directly grounded or grounded through the first resistor according to the driving signal.
In one embodiment, the parameter is a voltage fluctuation value, and the control circuit is specifically configured to compare the voltage fluctuation value of the filtered and amplified signal with a preset range of a reference voltage fluctuation value;
if the voltage fluctuation value is out of the preset range of the reference voltage fluctuation value, outputting a first driving signal for controlling the filter capacitor bank to be directly grounded; and if the voltage fluctuation value is within the preset range of the reference voltage fluctuation value, outputting a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor.
In one embodiment, the parameter is a voltage value, and the control circuit is specifically configured to further compare the voltage value of the filtered and amplified signal with a preset range of a reference voltage, output a first driving signal for controlling the filter capacitor bank to be directly grounded when the voltage value is outside the preset range of the reference voltage, and output a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor when the voltage value is within the preset range of the reference voltage.
In one embodiment, the filter capacitor bank comprises a first capacitor, a second capacitor, a third capacitor and a fourth capacitor, wherein a first end of the first capacitor is used for connecting a first end of a three-phase output end of the three-phase power grid, a first end of the second capacitor is used for connecting a second end of the three-phase output end of the three-phase power grid, and a first end of the third capacitor is used for connecting a third end of the three-phase output end of the three-phase power grid; the first end of the first resistor is connected to the second ends of the first capacitor, the second capacitor and the third capacitor, and the second end of the first resistor is connected to the first end of the fourth capacitor; and the second end of the fourth capacitor is used for grounding.
In one embodiment, the signal processing circuit includes an interference removing module, a voltage stabilizing and filtering module, an amplifying module and an output module, which are connected in sequence, wherein the interference removing module is connected to the signal port, and is configured to perform interference removing processing on the signal and output a first signal; the voltage stabilizing and filtering module is used for performing voltage stabilizing and filtering on the first signal and outputting a second signal; the amplifying module amplifies the second signal and outputs a third signal; and the output module outputs the third signal after voltage stabilization.
In one embodiment, the interference elimination module includes a common mode inductor, a first filter capacitor disposed on an input side of the common mode inductor, and a second filter capacitor and a first voltage dividing resistor disposed on an output side of the common mode inductor.
In one embodiment, the voltage-stabilizing filtering module comprises a voltage-stabilizing device connected to the output end of the interference-removing module, a filter device and a voltage-dividing device connected to the output side of the voltage-stabilizing device, and the filter device and the voltage-dividing device are connected in parallel.
In one embodiment, the amplifying module includes an operational amplifier, and a feedback device connected between an inverting input terminal and an output terminal of the operational amplifier.
In one embodiment, the ground switching circuit includes an isolation drive module and a relay assembly; the isolation driving module is connected with the control end of the control circuit and the coil of the relay assembly and used for receiving the driving signal and controlling the coil of the relay assembly to be electrified or powered off according to the driving signal, the relay assembly is provided with a movable contact connected with the first end of the first resistor, a first contact connected with the second end of the first resistor and a suspended second contact, and the movable contact and the second contact are normally closed.
In one embodiment, the isolation driving module comprises a photoelectric coupler and a switching tube, wherein an input end of the photoelectric coupler is connected with the control circuit, a control end of the switching tube is connected with an output end of the photoelectric coupler, a first conduction end of the switching tube is connected with a power supply through the coil, and a second conduction end of the switching tube is grounded.
A second aspect of the embodiments of the present application provides an electrical device, including a three-phase power grid three-phase output port and a signal port, the three-phase power grid three-phase output port has a three-phase filter circuit, the signal port has an input end of a signal, and an anti-interference circuit of the three-phase power grid three-phase output port is built in or externally arranged on the electrical device.
The anti-jamming circuit of the three-phase output port of the three-phase power grid can judge whether parameters of received signals are abnormal, and when the parameters of the signals are abnormal, the anti-jamming circuit controls the filter capacitor bank to be directly grounded and filters the signals of the signal port; when the parameters of the signals are not abnormal, the filter capacitor bank is controlled to be grounded through the first resistor, the impact current to the ground is reduced instantly when the equipment is powered on, and the system leakage switch is prevented from tripping.
Drawings
Fig. 1 is a schematic structural diagram of an anti-interference circuit of a three-phase output port of a three-phase power grid according to an embodiment of the present application;
FIG. 2 is a schematic diagram of an exemplary three-phase filter circuit in the three-phase output port anti-jamming circuit of the three-phase power grid shown in FIG. 1;
FIG. 3 is a schematic diagram of an exemplary circuit of a signal processing circuit in the anti-jamming circuit of the three-phase output port of the three-phase power grid shown in FIG. 1;
fig. 4 is a schematic circuit diagram of an example of an intelligent switch circuit in the three-phase output port anti-jamming circuit of the three-phase power grid shown in fig. 1.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.
It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.
Referring to fig. 1, an anti-jamming circuit for a three-phase output port of a three-phase power grid according to a preferred embodiment of the present invention includes a three-phase filter circuit 11, a signal processing circuit 12, a control circuit 13, and an intelligent switch circuit 14.
One end of the three-phase filter circuit 11 is connected with a three-phase output end of a three-phase power grid, the other end of the three-phase filter circuit is grounded, and the three-phase filter circuit 11 is used for filtering or buffering current at the moment of electrifying; the signal processing circuit 12 is connected with the input end of the signal port; the control circuit 13 is connected to the signal processing circuit 12, and is configured to compare the parameter of the signal with a preset range of a reference parameter, and output a corresponding driving signal according to a comparison result; the intelligent switch circuit 14 is connected with the control circuit 13 and the three-phase filter circuit 11, and is used for controlling the filter capacitor bank of the three-phase output port of the three-phase power grid to be directly grounded or grounded through the first resistor according to the driving signal.
Generally, the control circuit 13 is a chip having a logic processing function, such as a single chip microcomputer or a Digital Signal Processing (DSP) chip. The parameters of the signal may be voltage parameters, current parameters, or power parameters, etc.
In one embodiment, the control circuit 13 is specifically configured to compare the voltage fluctuation value of the filtered and amplified signal with a preset range of the reference voltage fluctuation value: for example, the preset range of the reference voltage fluctuation value of the filtered and amplified signal is set to be 0-5%. If the voltage fluctuation value of the signal is out of the preset range of the reference voltage fluctuation value (for example, the fluctuation is 6%), considering that the signal port has strong interference, and outputting a first driving signal for controlling the filter capacitor bank to be directly grounded; and if the voltage fluctuation value of the filtered and amplified signal is within a preset range (for example, fluctuation is 3%) of the reference voltage fluctuation value, outputting a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor.
In another embodiment, the control circuit 13 does not compare the voltage fluctuation value of the filtered and amplified signal with the preset reference voltage fluctuation value range, but directly compares the voltage value of the filtered and amplified signal with the preset reference voltage range (e.g. 1.95-2.05V), and outputs a first driving signal for controlling the filter capacitor bank to be directly grounded when the voltage value of the filtered and amplified signal is outside the preset reference voltage range; and outputting a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor when the voltage value of the filtered and amplified signal is within a preset range of the reference voltage.
It can be understood that the voltage fluctuation refers to fluctuation up and down with a voltage as a reference, for example, the reference voltage is 2V at any value, and the preset range of the reference voltage fluctuation is 5%, that is, the voltage of the filtered and amplified signal is within the preset range of the reference voltage normally between 1.95V and 2.05V, then the interference of the signal port is considered to be weak, and at this time, the control circuit 13 outputs a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor; if the voltage of the filtered and amplified signal is beyond 1.95V-2.05V, the interference of the signal port is considered to be strong, at this time, the control circuit 13 outputs a first driving signal for controlling the filter capacitor bank to be directly grounded, and the signal of the signal port is filtered by using the three-phase filter circuit 11.
Referring to fig. 2, in one embodiment, the three-phase filter circuit 11 includes a first capacitor C1, a second capacitor C2, a third capacitor C3 and a fourth capacitor C4, which form a filter capacitor set; the first end of the first capacitor C1 is used for being connected with the first end R of the three-phase output end of the three-phase power grid, the first end of the second capacitor C2 is used for being connected with the second end S of the three-phase output end of the three-phase power grid, and the first end of the third capacitor C3 is used for being connected with the third end T of the three-phase output end of the three-phase power grid; the three-phase filter circuit 11 further includes a first resistor R0, a first end of the first resistor R0 is connected to second ends of the first capacitor C1, the second capacitor C2 and the third capacitor C3, and a second end of the first resistor R0 is connected to a first end of the fourth capacitor C4; the second terminal of the fourth capacitor C4 is used for ground. The first resistor R0 is a buffer resistor, which can reduce the impact current to the ground at the moment of power-on and avoid the tripping of the system leakage switch; when the first resistor R0 is shorted, the filter capacitor bank is directly connected to ground, and the signal port signal can be filtered.
Referring to fig. 3, in one embodiment, the signal processing circuit 12 includes an interference removing module 121, a voltage stabilizing and filtering module 122, an amplifying module 123 and an output module 124, which are connected in sequence.
The interference removing module 121 is connected to the signal port, and configured to perform interference removing processing on the signal and output a first signal; the voltage stabilizing and filtering module 122 performs voltage stabilizing and filtering on the first signal output by the interference removing module 121 and outputs a second signal; the amplifying module 123 amplifies the second signal output by the voltage stabilizing filtering module 122 and outputs a third signal; the output module 124 stabilizes and outputs the third signal output by the amplifying module 123.
In one embodiment, the interference elimination module 121 includes a common mode inductor L1, a first filter capacitor C1 disposed on an input side of the common mode inductor L1, and a second filter capacitor C2 and a first voltage dividing resistor R1 disposed on an output side of the common mode inductor L1. The first filtering capacitor C1/the second filtering capacitor C2 may be formed by a plurality of capacitors connected in series and in parallel, the first voltage dividing resistor R1 may also be formed by a plurality of resistors connected in series and in parallel, and the interference removing module 121 is mainly used for removing various interference signals, such as common mode interference current and the like.
In one embodiment, the voltage-stabilizing filter module 122 includes a voltage-stabilizing device D1 connected to the output of the interference-removing module 121, and a filter device and a voltage-dividing device connected to the output side of the voltage-stabilizing device, wherein the filter device C3 and the voltage-dividing device R2 are connected in parallel. The voltage regulator device D1 is generally a three-terminal regulator, and the filter device C3 and the voltage divider device R2 are generally a filter capacitor and a resistor, respectively.
In one embodiment, the amplification module 123 includes an operational amplifier U1, and a feedback device R3 connected between the inverting input and output of the operational amplifier U1. The feedback device R3 generally includes a capacitive, resistive device. The output module 124 is also typically provided with a three-terminal regulator D2.
Referring to fig. 4, in one embodiment, the intelligent switching circuit 14 includes an isolation driving module 141 and a relay assembly 142.
The isolation driving module 141 is connected to the control end of the control circuit 13 and the coil 1421 of the relay assembly 142, and is configured to receive a driving signal and control the coil of the relay assembly 142 to be powered on or powered off according to the driving signal; the relay assembly 142 has a movable contact connected to a first end of a first resistor R0, a first contact connected to a second end of a first resistor R0, and a floating second contact. The movable contact and the second contact are normally closed, the default intelligent switch is disconnected, and when the intelligent switch needs to be closed, the control circuit 13 outputs a driving signal to drive the relay to act.
In one embodiment, the isolation driving module 141 includes a photocoupler U2 and a switching tube Q1, an input terminal of the photocoupler U2 is connected to the control circuit 13, a control terminal of the switching tube Q1 is connected to an output terminal of the photocoupler U2, a first conduction terminal of the switching tube Q1 is connected to the power supply through a coil of the relay assembly 142, and a second conduction terminal is grounded. Further, a schmitt buffer U3 for improving the driving capability of the driving signal and an indicator light D4 connected with the switching tube Q1 for indicating the action of the relay assembly are further disposed between the input end of the photocoupler U2 and the control circuit 13.
A second aspect of the embodiments of the present application provides an electrical device, which is powered by a three-phase power grid, where the anti-interference circuit of the three-phase output port of the three-phase power grid is built in or external to the electrical device. The electrical device may be a frequency converter, a drive, etc.
In one example, an external given voltage signal (0-10V) is input to the P1 port of the signal processing circuit 12 through the signal processing circuit 12 in fig. 3, and is processed by the port filtering and operational amplifier circuit, and is converted into a voltage signal (0-3V) to the P1-AD, that is, to the DSP chip, when the signal received by the DSP chip is not abnormal (i.e., the voltage fluctuation thereof is not more than 5%), the intelligent switch circuit 14 does not operate, the switch is kept open, and when the signal received by the DSP chip is abnormal (more than 5% of the voltage fluctuation), the DSP chip outputs a driving signal to the input terminal RO _ DSP of the intelligent circuit 14 through internal signal processing, and outputs a high or low level, so as to operate the relay, thereby realizing the switching of the on/off of the switch. Therefore, the DSP chip automatically selects to lead the filter capacitor bank to be directly grounded or to be grounded through the first resistor through internal comparison processing, so as to ensure that the system has high reliability while meeting the electromagnetic compatibility.
In one example, the electrical device is a frequency converter, and the filter capacitor bank uses a Y capacitor, so that the frequency converter can satisfy CE authentication and has both electromagnetic compatibility and stability.
The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.
Claims (10)
1. The utility model provides a three-phase electric wire netting three-phase output port anti jamming circuit which characterized in that includes:
the three-phase filter circuit comprises a filter capacitor bank and a first resistor, one end of the three-phase filter circuit is connected with a three-phase output port of the three-phase power grid, and the other end of the three-phase filter circuit is grounded;
the signal processing circuit is connected with the input end of the signal port and outputs the signal accessed by the signal port after filtering and amplifying;
the control circuit is connected with the signal processing circuit and used for comparing the parameters of the filtered and amplified signals with a preset range of reference parameters and outputting corresponding driving signals according to a comparison result;
and the intelligent switch circuit is connected with the three-phase filter circuit and the control circuit and is used for controlling the filter capacitor bank to be directly grounded or grounded through the first resistor according to the driving signal.
2. The three-phase output port anti-jamming circuit of claim 1, wherein the parameter is a voltage fluctuation value;
the control circuit is specifically used for comparing the voltage fluctuation value of the filtered and amplified signal with a preset range of a reference voltage fluctuation value; if the voltage fluctuation value is out of the preset range of the reference voltage fluctuation value, outputting a first driving signal for controlling the filter capacitor bank to be directly grounded; and if the voltage fluctuation value is within the preset range of the reference voltage fluctuation value, outputting a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor.
3. The three-phase output port anti-jamming circuit of claim 1, wherein the parameter is a voltage value;
the control circuit is specifically configured to compare the voltage value of the filtered and amplified signal with a preset range of a reference voltage; if the voltage value is out of the preset range of the reference voltage, outputting a first driving signal for controlling the filter capacitor bank to be directly grounded; and if the voltage value is within the preset range of the reference voltage, outputting a second driving signal for controlling the filter capacitor bank to be grounded through the first resistor.
4. The three-phase output port anti-jamming circuit according to claim 1, wherein the filter capacitor bank includes a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor, a first end of the first capacitor is configured to be connected to a first end of the three-phase output port of the three-phase power grid, a first end of the second capacitor is configured to be connected to a second end of the three-phase output port of the three-phase power grid, and a first end of the third capacitor is configured to be connected to a third end of the three-phase output port of the three-phase power grid; the first end of the first resistor is connected to the second ends of the first capacitor, the second capacitor and the third capacitor, and the second end of the first resistor is connected to the first end of the fourth capacitor; and the second end of the fourth capacitor is used for grounding.
5. The three-phase output port anti-jamming circuit of the three-phase power grid according to claim 1, wherein the signal processing circuit includes a jamming removing module, a voltage stabilizing and filtering module, an amplifying module and an output module, which are connected in sequence, and the jamming removing module is connected to the signal port and configured to perform jamming removing processing on the signal and output a first signal; the voltage stabilizing and filtering module is used for performing voltage stabilizing and filtering on the first signal and outputting a second signal; the amplifying module amplifies the second signal and outputs a third signal; and the output module outputs the third signal after voltage stabilization.
6. The three-phase power grid three-phase output port anti-jamming circuit of claim 5, wherein:
the interference elimination module comprises a common-mode inductor, a first filter capacitor arranged on the input side of the common-mode inductor, a second filter capacitor and a first divider resistor arranged on the output side of the common-mode inductor;
the voltage stabilizing and filtering module comprises a voltage stabilizing device connected to the output end of the interference removing module, and a filter device and a voltage dividing device connected to the output side of the voltage stabilizing device, wherein the filter device and the voltage dividing device are connected in parallel.
7. The three-phase power grid three-phase output port anti-jamming circuit of claim 5, wherein the amplification module includes an operational amplifier and a feedback device connected between an inverting input and an output of the operational amplifier.
8. The three-phase power grid three-phase output port anti-jamming circuit of any one of claims 1 to 7, wherein the smart switching circuit comprises an isolation drive module and a relay assembly; the isolation driving module is connected with the control end of the control circuit and the coil of the relay assembly and used for receiving the driving signal and controlling the coil of the relay assembly to be electrified or powered off according to the driving signal, the relay assembly is provided with a movable contact connected with the first end of the first resistor, a first contact connected with the second end of the first resistor and a suspended second contact, and the movable contact and the second contact are normally closed.
9. The anti-jamming circuit for the three-phase output port of the three-phase power grid according to claim 8, wherein the isolation driving module comprises a photoelectric coupler and a switching tube, an input end of the photoelectric coupler is connected to the control circuit, a control end of the switching tube is connected to an output end of the photoelectric coupler, a first conduction end of the switching tube is connected to the power supply through the coil, and a second conduction end of the switching tube is grounded.
10. An electrical device comprising a three-phase power grid three-phase output port and a signal port, wherein the three-phase power grid three-phase output port is provided with a three-phase filter circuit, and the signal port is provided with a signal input end, and wherein the three-phase power grid three-phase output port anti-interference circuit of any one of claims 1 to 9 is internally or externally arranged on the electrical device.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202121433762.2U CN215871182U (en) | 2021-06-25 | 2021-06-25 | Three-phase power grid three-phase output port anti-interference circuit and electrical equipment |
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| CN202121433762.2U CN215871182U (en) | 2021-06-25 | 2021-06-25 | Three-phase power grid three-phase output port anti-interference circuit and electrical equipment |
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