CN107689620B - Three-phase power protection device and method - Google Patents

Abstract

The invention relates to the field of electric power technology, in particular to a three-phase power protection device and method. The three-phase power protection device is applied to a three-phase power supply connected to a three-phase load, and the three-phase power protection device includes a phase sequence detection module, a voltage detection module, a current detection module, a control module and a relay execution module. The phase sequence detection module, the voltage detection module, and the current detection module are respectively connected to the three-phase power supply, so that the control module can obtain the phase sequence state obtained by detecting the phase sequence by the phase sequence detection module, and the phase sequence state obtained by detecting the voltage by the voltage detection module. When there is an abnormal state in the voltage state of the current detection module and the current state detected by the current detection module, the relay execution module is controlled to disconnect the connection between the three-phase power supply and the three-phase load. Through the above arrangement, the phase sequence, voltage and current of the three-phase power supply can be effectively monitored, thereby effectively ensuring the safety of the three-phase load connected to the three-phase power supply.

Description

Three-phase power protection device and method

technical field

The invention relates to the field of electric power technology, in particular to a three-phase power protection device and method.

Background technique

With the progress of society and the continuous improvement of people's living standards, users have higher and higher requirements for the safety and reliability of power supply. Especially in the industrial control system, three-phase loads are mostly used. For some special electromechanical equipment, such as elevators, central air conditioners, cranes, liquid cooling units, three-phase motors, etc., when the three-phase power supply fails, it is easy to cause equipment failure. be damaged or even have an accident. Therefore, it is an urgent technical problem to effectively monitor and ensure the safety of the three-phase power supply and the three-phase load.

Contents of the invention

In view of this, the object of the present invention is to provide a three-phase power supply protection device and method, the three-phase power supply protection device is applied to a power system including three-phase power supply. By setting the phase sequence detection module, voltage detection module, current detection module, control module and relay execution module, the phase sequence, voltage and current of the three-phase power supply can be effectively monitored, and then the three-phase load connected to the three-phase power supply can be effectively guaranteed security.

In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solutions:

A three-phase power supply protection device, which is applied to a three-phase power supply connected to a three-phase load. The three-phase power supply protection device includes: a phase sequence detection module, a voltage detection module, a current detection module, a control module and a relay execution module. The phase sequence detection module has a plurality of input terminals connected to each phase of the three-phase power supply, the output terminal is connected to the control module, the input terminal of the voltage detection module is connected to the three-phase power supply, and the output terminal is connected to the three-phase power supply. terminal is connected to the control module, the input terminal of the current detection module is connected to the three-phase power supply, the output terminal is connected to the input port of the control module, and the control terminal of the relay execution module is connected to the control module , the input end is connected to the three-phase power supply, and the output end is connected to the three-phase load;

The phase sequence detection module detects the phase sequence of the three-phase power supply to obtain a phase sequence signal and sends it to the control module, and the voltage detection module detects the voltage value of the three-phase power supply and sends it to the control module. The current detection module detects the current value of the three-phase power supply and sends it to the control module;

The control module stores a preset phase-sequence corresponding relationship, a preset current value range, and a preset voltage value range, and the control module obtains the three-phase power supply according to the phase-sequence signal and the preset phase-sequence corresponding relationship. phase sequence state, the voltage state of the three-phase power supply is obtained according to the voltage value of the three-phase power supply and the preset voltage value range, and the three-phase power supply is obtained according to the current value of the three-phase power supply and the preset current value range When there is an abnormal state in the phase sequence state, voltage state and current state, the relay execution module is controlled to disconnect the connection between the three-phase power supply and the three-phase load.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power supply protection device, there are four signal input terminals of the phase sequence detection module, which are respectively connected to the first phase, the second phase, the The third phase is connected to the neutral line N, and the signal output terminals are four and are respectively connected to the control module. The phase sequence signal obtained by the phase sequence detection module detecting the phase sequence of the three-phase power supply is a sampling signal, so The control module judges whether the phase sequence of the three-phase power supply is abnormal according to the corresponding relationship between the sampling signal and the preset phase sequence, and obtains the corresponding abnormal phase sequence state when it is abnormal, and controls the relay execution module to disconnect the three-phase power supply. phase power supply and the connection between the three-phase load.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power protection device, the three-phase power protection device further includes a display module, and the display module is connected to the control module to receive and display the information sent by the control module. The phase sequence state, voltage state and current state of the three-phase power supply.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power supply protection device, the three-phase power supply protection device further includes a work indication circuit, the work indication circuit is connected to the control module, and the control module The state of the three-phase power supply controls the working state of the working indication circuit.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power supply protection device, the voltage detection module is an overvoltage detection module, the current detection module is an overcurrent detection module, and the control module adopts industrial grade Chip PIC MCU.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power supply protection device, the three-phase power supply protection device further includes a local power supply, and the local power supply and the phase sequence detection module, voltage detection module, and current detection module , the control module and the relay execution module are connected separately.

The present invention also provides a three-phase power protection method, which is applied to the above-mentioned three-phase power protection device. The control module stores a preset phase sequence correspondence relationship, a preset current value range, and a preset voltage value range. Methods include:

The phase sequence detection module detects the phase sequence of the three-phase power supply and sends it to the control module.

The voltage detection module detects the voltage value of the three-phase power supply and sends it to the control module.

The current detection module detects the current value of the three-phase power supply and sends it to the control module.

The control module obtains the phase sequence state of the three-phase power supply according to the corresponding relationship between the phase sequence of the three-phase power supply and the preset phase sequence, and obtains the phase sequence state of the three-phase power supply according to the voltage value of the three-phase power supply and the preset voltage value range. The voltage state of the three-phase power supply, the current state of the three-phase power supply is obtained according to the current value of the three-phase power supply and the preset current value range, and whether each state is an abnormal state is judged.

When there is an abnormal state in the phase sequence state, voltage state and current state, the control module controls the relay execution module to disconnect the three-phase power supply and the three-phase load.

In a preferred embodiment of the present invention, in the above-mentioned three-phase power supply protection method, the step of the control module controlling the relay execution module to disconnect the connection between the three-phase power supply and the three-phase load includes:

The control module controls the relay execution module to disconnect the three-phase power supply and the three-phase load and start timing, and adjust the abnormal state of the three-phase power supply after the timing is started so that the three-phase power supply Phase power returns to normal.

The three-phase power protection method also includes:

When the timing reaches the preset duration, the control module acquires the phase sequence state, voltage state and current state of the three-phase power supply detected by the phase sequence detection module, the voltage detection module and the current detection module respectively, and When there is no abnormal state in the phase sequence state, voltage state, and current state, the relay execution module is controlled to connect the three-phase power supply and the three-phase load, so that the three-phase power supply is connected to the three-phase load powered by.

In a preferred embodiment of the present invention, in the above three-phase power protection method, when the three-phase power protection device further includes a display module connected to the control module, the phase sequence state, voltage state and current state When there is an abnormality in the three-phase power supply protection method, the three-phase power supply protection method also includes:

The display module is controlled to display the phase sequence state, voltage state and current state of the three-phase power supply.

In a preferred embodiment of the present invention, in the above three-phase power supply protection method, the three-phase power supply protection device further includes a working state indicating circuit connected to the control module, and the working state indicating circuit includes a plurality of indicating light, the phase sequence detection module, the voltage detection module and the current detection module respectively have at least one indicator light, and the method also includes:

When the phase sequence detection module, voltage detection module, and current detection module detect that there is an abnormality in the phase sequence state, voltage state, or current state, the control module controls the phase sequence detection module, voltage detection module, and voltage detection module whose detected state is abnormal. The indicator light corresponding to the module or current detection module is on or off.

A three-phase power supply protection device and method provided by the present invention, the three-phase power supply protection device is applied to a three-phase power supply connected to a three-phase load, and the three-phase power supply protection device is equipped with a phase sequence detection module and a voltage detection module , a current detection module, a control module, and a relay execution module, the phase sequence detection module, the voltage detection module, and the current detection module are respectively connected to the three-phase power supply, so that the control module can be detected by the phase sequence detection module When there is an abnormality in the phase sequence state obtained by the phase sequence, the voltage state obtained by the voltage detected by the voltage detection module, and the current state obtained by the current detected by the current detection module, the relay execution module is controlled to disconnect the three-phase power supply and the connection between the three-phase loads. Through the above arrangement, the phase sequence, voltage and current of the three-phase power supply can be effectively monitored, thereby effectively ensuring the safety of the three-phase load connected to the three-phase power supply.

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some of the embodiments of the present invention, and therefore should not It is regarded as limiting the scope of protection of the present invention, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

Fig. 1 is a structural block diagram of a three-phase power protection device provided by an embodiment of the present invention.

Fig. 2 is an application block diagram of a three-phase power protection device provided by an embodiment of the present invention.

Fig. 3 is a pin diagram of a phase sequence detection module provided by an embodiment of the present invention.

Fig. 4 is a pin diagram of a control module provided by an embodiment of the present invention.

Fig. 5 is a schematic diagram of an alarm circuit provided by an embodiment of the present invention.

Fig. 6 is another structural block diagram of a three-phase power protection device provided by an embodiment of the present invention.

FIG. 7 is a schematic flowchart of a three-phase power protection method provided by an embodiment of the present invention.

Icons: 100-three-phase power protection device; 110-phase sequence detection module; 120-voltage detection module; 130-current detection module; 140-control module; 150-relay execution module; 160-alarm circuit; 170-display module; 180-work indication circuit; 190-local power supply; 210-button switch; 300-three-phase power supply; 500-three-phase load.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in this drawing may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention. It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or Integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Please refer to FIG. 1 and FIG. 2, the present invention provides a three-phase power supply protection device 100, which is applied to a three-phase power supply 300 connected with a three-phase load 500, the three-phase power supply protection device 100 is connected to the three-phase power supply 300 to The effective monitoring function of the three-phase power supply 300 is realized, and then the safety of the three-phase load 500 is effectively guaranteed when the three-phase power supply 300 is abnormal.

The three-phase power supply protection device 100 includes: a phase sequence detection module 110, a voltage detection module 120, a current detection module 130, a control module 140 and a relay execution module 150, and the input terminals of the phase sequence detection module 110 are multiple and respectively connected to each phase of the three-phase power supply 300, the output end is connected to the control module 140, the input end of the voltage detection module 120 is connected to the three-phase power supply 300, and the output end is connected to the control module 140, The input terminal of the current detection module 130 is connected to the three-phase power supply 300, the output terminal is connected to the input port of the control module 140, the control terminal of the relay execution module 150 is connected to the control module 140, and the input terminal is connected to the control module 140. It is connected with the three-phase power supply 300 and the output terminal is connected with the three-phase load 500 .

The phase sequence detection module 110 detects the phase sequence of the three-phase power supply 300 and sends it to the control module 140, and the voltage detection module 120 detects the voltage value of the three-phase power supply 300 and sends it to the control module 140 , the current detection module 130 detects the current value of the three-phase power supply 300 and sends it to the control module 140 .

The control module 140 stores a preset phase sequence correspondence, a preset current value range, and a preset voltage value range, and the control module 140 obtains according to the phase sequence of the three-phase power supply 300 and the preset phase sequence correspondence relationship The phase sequence state of the three-phase power supply 300, the voltage state of the three-phase power supply 300 is obtained according to the voltage value of the three-phase power supply 300 and the preset voltage range, and according to the current value of the three-phase power supply 300 and the preset voltage value range Set the current value range to obtain the current state of the three-phase power supply 300, and when there is an abnormality in the phase sequence state, voltage state, and current state, control the relay execution module 150 to disconnect the three-phase power supply 300 from the connection between three-phase loads 500 .

Through the above settings, when the three-phase power supply 300 supplies power to the three-phase load 500, the three-phase power supply 300 will be effectively prevented from being caused by abnormal phase sequence, abnormal voltage and/or abnormal current in the three-phase power supply 300. The three-phase load 500 connected to 300 breaks down and even causes an accident.

Please refer to FIG. 3. In this embodiment, the phase sequence detection module 110 has four input terminals, which are respectively connected to the first phase, second phase, third phase and neutral line of the three-phase power supply 300. N connection. The phase sequence detection module 110 has four signal output terminals and is connected to the control module 140 respectively. The phase sequence signal obtained by the phase sequence detection module 110 detecting the phase sequence of the three-phase power supply 300 is a sampling signal, The control module 140 judges whether the phase sequence of the three-phase power supply 300 is abnormal according to the corresponding relationship between the sampling signal and the preset phase sequence, and obtains the corresponding abnormal phase sequence state when it is abnormal, and controls the relay execution module 150 to shut off. Open the connection between the three-phase power supply 300 and the three-phase load 500 .

Specifically, the output terminal of the phase sequence detection module 110 has four signal lines, and the corresponding output sampling signals are respectively the first signal, the second signal, the third signal and the fourth signal. In this embodiment, when the first signal, the second signal, the third signal and the fourth signal are all high-level signals, it is normal, and when there is at least one low-level signal, it is abnormal. And in case of abnormality, according to the preset phase sequence correspondence relationship, whether the phase sequence is a reverse sequence or lack of phase is obtained, and in the case of lack of phase, the specific missing phase is obtained.

For example, the preset phase sequence correspondence relationship may be: when the first signal, the second signal, the third signal and the fourth signal are at a high level, it is a normal state; when the first signal, the second signal and the fourth signal are all When it is high level and the third signal is low level, it is the reverse order; when the first signal and the fourth signal are high level and the second signal and the third signal are low level, the first phase is missing; when the second signal When the signal and the third signal are high level and the first signal and the fourth signal are low level, the second phase is missing; when the first signal, the second signal and the third signal are high level and the fourth signal is low level, the second phase is missing The third phase; when the first signal, the second signal or the third signal is low level and the fourth signal is high level, the first phase and the second phase are absent; when the first signal is high level and the second When the signal, the third signal and the fourth signal are low level, the first phase and the third phase are missing; when the first signal, the third signal and the fourth signal are all low level and the second phase sequence is a high level signal The second phase and the third phase are missing; when the first signal, the second signal, the third signal and the fourth signal are all at low level, the first phase, the second phase and the third phase are missing.

Through the above settings, the accuracy of phase sequence detection can be effectively ensured, so that when the phase sequence of the three-phase power supply 300 is abnormal, the specific missing phase of the three-phase power supply 300 can be obtained according to the preset phase sequence correspondence, so that the working Personnel can carry out maintenance according to the three-phase power supply 300 that is missing, which greatly improves the maintenance efficiency of the staff and effectively reduces the operation and maintenance cost.

Optionally, in this embodiment, the voltage detection module 120 has multiple input ports, and the first phase, the second phase, the third phase and the neutral line N of the three-phase power supply 300 are respectively connected to the corresponding An input port of the voltage detection module 120, so that the voltage detection module 120 detects the voltages of the first phase, the second phase and the third phase to obtain the first voltage signal, the second voltage signal and the third voltage signal and sent to the control module 140. The control module 140 judges whether the voltage state of the three-phase power supply 300 is abnormal according to the first voltage signal, the second voltage signal, the third voltage signal and the preset voltage value range, and obtains the corresponding abnormal voltage when abnormal State and control the relay execution module 150 to disconnect the three-phase power supply 300 and the three-phase load 500 .

Optionally, in this embodiment, the voltage detection module 120 is an overvoltage and undervoltage detection module. Specifically, the first voltage signal, the second voltage signal and the third voltage signal are detected voltage values corresponding to each phase, and when the voltage values of each voltage signal are within the preset voltage value range, then The voltage of each phase of the three-phase power supply 300 is normal; when at least one of the first voltage signal, the second voltage signal or the third voltage signal is outside the preset voltage value range, the at least one voltage The voltage of the corresponding phase of the signal is abnormal, and when the voltage of the at least one voltage signal exceeds the maximum value of the preset voltage value range, it is overvoltage, and when it is lower than the minimum value of the preset voltage value range, it is undervoltage. Through the above settings, the accuracy of the above voltage detection results can be effectively guaranteed.

Optionally, there are multiple input ports of the current detection module 130, and the first phase, the second phase, and the third phase of the three-phase power supply 300 are respectively connected to one input port of the current detection module 130, so that all The current detection module 130 detects the currents of the first phase, the second phase and the third phase to obtain a first current signal, a second current signal and a third current signal and send them to the control module 140, the control module 140 judge whether the current state of the three-phase power supply 300 is abnormal according to the first current signal, the second current signal, the third current signal and the preset current value range, and obtain the corresponding abnormal current state and control The relay execution module 150 disconnects the connection between the three-phase power supply 300 and the three-phase load 500 .

Optionally, in this embodiment, the current detection module 130 is an overcurrent and undercurrent detection module. Specifically, the first current signal, the second current signal and the third current signal are detected current values corresponding to each phase, and when the current values of each current signal are within the preset current value range, then The current of each phase of the three-phase power supply 300 is normal; when at least one of the first current signal, the second current signal or the third current signal is outside the preset current value range, the at least one current The current of the corresponding phase of the signal is abnormal, and when the current of the at least one current signal exceeds the maximum value of the preset current value range, it is an overcurrent, and when it is lower than the minimum value of the preset current value range, it is an undercurrent. Through the above settings, the accuracy of the above current detection results can be effectively guaranteed.

Optionally, when there is an abnormality in the phase sequence state, voltage state, and current state, control the relay execution module 150 to disconnect the connection between the three-phase power supply 300 and the three-phase load 500, the The control module 140 is also used to adjust the phase sequence, voltage and/or current of the three-phase power supply 300 according to the abnormality in the phase sequence state, voltage state and current state, so that the phase sequence, voltage and/or current of the three-phase power supply 300 The current returns to a normal state, and the relay execution module 150 is controlled to connect the three-phase power supply 300 and the three-phase load 500 so that the three-phase power supply 300 supplies power to the three-phase load 500 again.

Optionally, the relay execution module 150 has multiple input terminals, and the first phase, the second phase, the third phase and the neutral line N of the three-phase power supply 300 are connected to one of the relay execution modules 150 respectively. input. When the phase sequence detection module 110, the voltage detection module 120 and/or the current detection module 130 detect that the first phase, the second phase and/or the third phase are abnormal, the relay execution module 150 controls the second phase The first phase, the second phase and the third phase are respectively disconnected from the three-phase load 500 to effectively ensure the safety of the three-phase power supply 300 .

Please refer to FIG. 4 , in this embodiment, the control module 140 is an integrated circuit chip with signal processing capability. It may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP) and the like. It can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components. Various methods, steps and logic block diagrams disclosed in the embodiments of the present invention may be implemented or executed. A general-purpose processor may be a microprocessor, any conventional processor, or the like. In this embodiment, the control module 140 is a single chip microcomputer. Specifically, the control module 140 is a single-chip microcomputer using an industrial grade chip PIC.

Optionally, the three-phase power supply protection device 100 also includes an alarm circuit 160, the alarm circuit 160 is connected to the control module 140, and the control module 140 controls the alarm circuit 160 in the phase sequence state, voltage When there is an abnormality in the state and the current state, the alarm circuit 160 is controlled to send out an alarm signal. The alarm circuit 160 may include but not limited to one or more of a sound alarm circuit, a light alarm circuit, a sound and light alarm circuit or a short message alarm circuit, as long as the alarm can be realized to effectively prompt the staff. Please refer to FIG. 5 , in this embodiment, the alarm circuit 160 is an audible and visual alarm circuit.

Optionally, in this embodiment, there are multiple alarm circuits 160, and the phase sequence detection module 110, voltage detection module 120, and current detection module 130 correspond to one alarm circuit 160, so that the phase sequence When the sequence detection module 110, the voltage detection module 120 or the current detection module 130 detects an abnormal state, the corresponding alarm circuit 160 is controlled to send an alarm signal.

Optionally, in this embodiment, there are multiple alarm circuits 160, and the phase sequence detection module 110, voltage detection module 120, and current detection module 130 correspond to one alarm circuit 160, so that the phase sequence When the sequence detection module 110, the voltage detection module 120 or the current detection module 130 detects an abnormal state, the control module 140 controls the corresponding alarm circuit 160 to send an alarm signal.

In order to prevent the alarm circuit 160 from affecting the work of the staff during the maintenance process of the staff. It may be under the control of the control module 140 that the alarm circuit 160 will alarm and stop the alarm automatically after a preset period of time, or the alarm signal may be cut off manually by the user. Please refer to FIG. 6 , in this embodiment, optionally, the three-phase power protection device 100 further includes a button switch 210 , and the button switch 210 is connected to the control module 140 . The staff can manually cut off the alarm signal sent by the alarm circuit 160 by pressing the button switch 210 .

In this embodiment, the three-phase power protection device 100 further includes a local power supply 190 connected to the phase sequence detection module 110 , the voltage detection module 120 , the current detection module 130 and the control module 140 respectively. The local power supply 190 supplies power to the phase sequence detection module 110 , the voltage detection module 120 , the current detection module 130 and the control module 140 respectively.

Optionally, in this embodiment, the three-phase power protection device 100 further includes a display module 170, the display module 170 is connected to the control module 140 to receive and display the three-phase power sent by the control module 140 300 phase sequence status, voltage status and current status. So that the staff can intuitively know whether the three-phase power supply 300 is abnormal, and when the abnormality occurs, the specific situation of the abnormality is displayed.

In order to further play a good role in prompting the staff. Optionally, in this embodiment, the three-phase power supply protection device 100 further includes a work indication circuit 180, and the work indication circuit 180 includes a plurality of indicator lights, each of which is connected to the control module 140 , and the phase sequence detection module 110, the voltage detection module 120 and the current detection module 130 respectively have at least one indicator light. The control module 140 controls each of the indicator lights to light up when the detection results of the phase sequence detection module 110, the voltage detection module 120 and the current detection module 130 are normal, and the phase sequence detection module 110, the voltage detection module 120 or When the detection result of at least one detection module in the current detection module 130 is abnormal, the indicator light corresponding to the at least one detection module is controlled to turn off.

Optionally, in this embodiment, the phase sequence detection module 110 corresponds to a plurality of indicator lights, and each indicator light corresponds to an abnormal state detected by the phase sequence detection module 110, and the control module 140 According to the abnormal state detected by the phase sequence detection module 110, the corresponding indicator light is controlled to turn off. The voltage detection module 120 corresponds to a plurality of indicator lights, and each indicator light corresponds to an abnormal state detected by the voltage detection module 120, and the control module 140 detects the abnormal state according to the voltage detection module 120 The indicator light corresponding to the control goes out. The current detection module 130 corresponds to a plurality of indicator lights, and each indicator light corresponds to an abnormal state detected by the current detection module 130, and the control module 140 detects the abnormal state according to the current detection module 130 The indicator light corresponding to the control goes out.

Please refer to FIG. 7 , on the basis of the above, the present invention also provides a three-phase power supply 300 protection method, which is applied to the above-mentioned three-phase power supply protection device 100, and the method includes five steps from step S110 to step S150:

Step S110 : the phase sequence detection module 110 detects the phase sequence of the three-phase power supply 300 and sends it to the control module 140 .

Step S120 : the voltage detection module 120 detects the voltage value of the three-phase power supply 300 and sends it to the control module 140 .

Step S130 : the current detection module 130 detects the current value of the three-phase power supply 300 and sends it to the control module 140 .

Wherein, the control module 140 stores a preset phase sequence correspondence relationship, a preset current range and a preset voltage range.

Step S140: The control module 140 obtains the phase sequence state of the three-phase power supply 300 according to the phase sequence of the three-phase power supply 300 and the preset phase sequence correspondence relationship, and according to the voltage value of the three-phase power supply 300 and the preset phase sequence The voltage value range obtains the voltage state of the three-phase power supply 300, obtains the current state of the three-phase power supply 300 according to the current value of the three-phase power supply 300 and the preset current value range, and judges whether each state is an abnormal state.

Step S150: When there is an abnormal state in the phase sequence state, voltage state and current state, the control module 140 controls the relay execution module 150 to disconnect the three-phase power supply 300 and the three-phase load 500 Connection.

Optionally, the step of the control module 140 controlling the relay execution module 150 to disconnect the connection between the three-phase power supply 300 and the three-phase load 500 includes:

The control module 140 controls the relay execution module 150 to disconnect the connection between the three-phase power supply 300 and the three-phase load 500 and start timing, and adjust the abnormal state of the three-phase power supply 300 after the timing starts To restore the three-phase power supply 300 to normal.

Wherein, the way of adjusting the abnormal state of the three-phase power supply 300 to restore the three-phase power supply 300 to normal can be manual adjustment or automatic adjustment. For example, when the voltage unbalance degree and current unbalance degree of the three-phase power supply 300 are within the corresponding preset range, the three-phase power supply 300 can be restored to normal through automatic adjustment, and the preset range can be But not limited to less than 30%, less than 40% or less than 50%, no specific limitation here. When the voltage unbalance degree and current unbalance degree of the three-phase power supply 300 exceed the corresponding preset ranges, the three-phase power supply 300 can be restored to normal through manual adjustment.

The protection method of the three-phase power supply 300 further includes: when the timing reaches a preset duration, the control module 140 obtains the three-phase sequence detected by the phase sequence detection module 110, the voltage detection module 120 and the current detection module 130 respectively. The phase sequence state, voltage state and current state of the phase power supply 300, and when there is no abnormal state in the phase sequence state, voltage state and current state, control the relay execution module 150 to communicate with the three-phase power supply 300 and the The three-phase load 500 is configured so that the three-phase power supply 300 supplies power to the three-phase load 500 .

Optionally, when the three-phase power protection device 100 further includes a display module 170 connected to the control module 140, and there is an abnormality in the phase sequence state, voltage state and current state, the three-phase power supply 300 Protection methods also include:

The display module 170 is controlled to display the phase sequence state, voltage state and current state of the three-phase power supply 300 .

Optionally, when the three-phase power protection device 100 further includes an alarm circuit 160 connected to the control module 140, and there is an abnormality in the phase sequence state, voltage state, and current state, the control module 140 controls the The step of disconnecting the connection between the three-phase power supply 300 and the three-phase load 500 by the relay execution module 150 includes:

The control module 140 controls the relay execution module 150 to disconnect the connection between the three-phase power supply 300 and the three-phase load 500 and controls the alarm circuit 160 to send out an alarm signal.

To sum up, the present invention provides a three-phase power supply protection device 100 and a method. The three-phase power supply protection device 100 is implemented by setting a phase sequence detection module 110, a voltage detection module 120, a current detection module 130, a control module 140 and a relay. Module 150, so that the control module 140 can obtain the phase sequence state according to the phase sequence detected by the phase sequence detection module 110, the voltage state obtained by the voltage detected by the voltage detection module 120, and the current state obtained by the current detected by the current detection module 130 When there is an abnormality in the system, control the relay execution module 150 to disconnect the connection between the three-phase power supply 300 and the three-phase load 500, so as to monitor the phase sequence, voltage and current of the three-phase power supply 300, and then The safety of the three-phase load 500 connected to the three-phase power supply 300 is effectively guaranteed. By setting the alarm circuit 160, the display module 170 and the work indication circuit 180, the staff can be effectively prompted and the staff can be further processed conveniently.

It should be noted that the term "comprising" or any other variant thereof is intended to cover a non-exclusive inclusion such that a process, article or device comprising a set of elements includes not only those elements but also other elements not expressly listed, Or also includes elements inherent in such a process, article or equipment. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, article or device comprising said element.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (9)

1. a kind of three phase mains protective device, applied to the three phase mains being connect with threephase load, which is characterized in that the three-phase Apparatus for protecting power supply includes: that Phase sequence detection module, voltage detection module, current detection module, control module and relay execute Module, the input terminal of the Phase sequence detection module be it is multiple and respectively with the three phase mains it is each be connected, output end with Control module connection, the input terminal of the voltage detection module connect with the three phase mains, output end and the control Module connection, the input terminal of the current detection module is connect with the three phase mains, output end is defeated with the control module Inbound port connection, the control terminal of the relay execution module connect with the control module, input terminal and the three phase mains Connection, output end are connect with the threephase load；

The phase sequence that the Phase sequence detection module detects the three phase mains obtains phase sequential signal and sends to the control module, institute It states voltage detection module to detect the voltage value of the three phase mains and be sent to the control module, the current detection module inspection It surveys the current value of the three phase mains and is sent to the control module；

The signal input part of the Phase sequence detection module is four, and respectively with the first phase of the three phase mains, the second phase, the Three-phase and neutral conductor N connection, signal output end are four and connect respectively with the control module that the sampling of corresponding output is believed It number is the first signal, second signal, third signal and fourth signal respectively, the Phase sequence detection module detects the three-phase electricity The phase sequential signal that the phase sequence in source obtains is sampled signal, and the control module is closed according to the sampled signal and default phase sequence are corresponding System judge whether the phase sequence of the three phase mains abnormal, and obtain corresponding abnormal phase sequence state when abnormal and described in controlling after Electric appliance execution module disconnects the connection between the three phase mains and the threephase load；

It is normal condition when first signal, second signal, third signal and fourth signal are high level；When described first It is backward when signal, second signal and fourth signal are all high level and third signal is low level；When first signal, The first phase is lacked when with fourth signal be high level and second signal and third signal is low level；When the second signal and third The second phase is lacked when signal is high level and the first signal and fourth signal are low level；When first signal, second signal and Third phase is lacked when third signal is high level and fourth signal is low level；When first signal, second signal or third are believed It number is low level and when fourth signal is high level lacks the first phase and the second phase；When first signal is high level and described the The first phase and third phase are lacked when binary signal, third signal and fourth signal are low level；When first signal, third signal and The second phase and third phase are lacked when fourth signal is all low level and the second phase sequence is high level signal；When first signal, When binary signal, third signal and fourth signal are all low level, the first phase, the second phase and third phase are lacked；

Default phase sequence corresponding relationship, pre-set current value range and preset voltage value range are stored in the control module, it is described Control module obtains the phase sequence state of the three phase mains according to the phase sequential signal and default phase sequence corresponding relationship, according to described The voltage value and preset voltage value range of three phase mains obtain the voltage status of the three phase mains, according to the three phase mains Current value and pre-set current value range obtain the current status of the three phase mains, when the phase sequence state, voltage status and There are when abnormality, control the relay execution module to disconnect the three phase mains and the threephase load in current status Between connection.

2. three phase mains protective device according to claim 1, which is characterized in that the three phase mains protective device is also wrapped Display module is included, the display module connect the three-phase electricity to receive and show the control module transmission with the control module Phase sequence state, voltage status and the current status in source.

3. three phase mains protective device according to claim 1, which is characterized in that the three phase mains protective device is also wrapped Working indicating is included, the working indicating is connect with the control module, and the control module is according to the three-phase electricity The state in source controls the working condition of the working indicating.

4. three phase mains protective device according to claim 1, which is characterized in that the voltage detection module was to owe electricity Detection module is pressed, the current detection module was undercurrent detection module, and the control module is using technical grade chip PIC's Single-chip microcontroller.

5. three phase mains protective device according to claim 1, which is characterized in that the three phase mains protective device is also wrapped Include local power supply, the local power supply and the Phase sequence detection module, voltage detection module, current detection module, control module It is separately connected with relay execution module.

6. a kind of three phase mains guard method, applied to three phase mains protective device described in claim 1-5 any one, It is characterized in that, default phase sequence corresponding relationship, pre-set current value range and preset voltage value range is stored in the control module, The described method includes:

The phase sequence of Phase sequence detection module detection three phase mains is sent to control module；

Voltage detection module detects the voltage value of the three phase mains and is sent to the control module；

Current detection module detects the current value of the three phase mains and is sent to the control module；

The control module obtains the phase of the three phase mains according to the phase sequence and default phase sequence corresponding relationship of the three phase mains Sequence state obtains the voltage status of the three phase mains, root according to the voltage value of the three phase mains and preset voltage value range The current status of the three phase mains is obtained according to the current value and pre-set current value range of the three phase mains, and judges each state It whether is abnormality；

The signal input part of the Phase sequence detection module is four, and respectively with the first phase of the three phase mains, the second phase, the Three-phase and neutral conductor N connection, signal output end are four and connect respectively with the control module that the sampling of corresponding output is believed It number is the first signal, second signal, third signal and fourth signal respectively, the Phase sequence detection module detects the three-phase electricity The phase sequential signal that the phase sequence in source obtains is sampled signal, and the control module is closed according to the sampled signal and default phase sequence are corresponding System judge whether the phase sequence of the three phase mains abnormal, and obtain corresponding abnormal phase sequence state when abnormal and described in controlling after Electric appliance execution module disconnects the connection between the three phase mains and the threephase load；

It is normal condition when first signal, second signal, third signal and fourth signal are high level；When described first It is backward when signal, second signal and fourth signal are all high level and third signal is low level；When first signal, The first phase is lacked when with fourth signal be high level and second signal and third signal is low level；When the second signal and third The second phase is lacked when signal is high level and the first signal and fourth signal are low level；When first signal, second signal and Third phase is lacked when third signal is high level and fourth signal is low level；When first signal, second signal or third are believed It number is low level and when fourth signal is high level lacks the first phase and the second phase；When first signal is high level and described the The first phase and third phase are lacked when binary signal, third signal and fourth signal are low level；When first signal, third signal and The second phase and third phase are lacked when fourth signal is all low level and the second phase sequence is high level signal；When first signal, When binary signal, third signal and fourth signal are all low level, the first phase, the second phase and third phase are lacked；

When in the phase sequence state, voltage status and current status there are when abnormality, described in the control module control Relay execution module disconnects the connection between the three phase mains and the threephase load.

7. three phase mains guard method according to claim 6, which is characterized in that the control module controls the relay Device execution module disconnects the step of connection between the three phase mains and the threephase load and includes:

The control module controls the relay execution module and disconnects company between the three phase mains and the threephase load Timing is connect and started, and adjusts the abnormality of the three phase mains so that the three phase mains restores just after starting timing Often；

The three phase mains guard method further include:

When timing reaches default timing duration, the control module obtain the Phase sequence detection module, voltage detection module with And phase sequence state, voltage status and the current status of the three phase mains that current detection module detects respectively, and When abnormality being not present in the phase sequence state, voltage status and current status, controls the relay execution module and connect Lead to the three phase mains and the threephase load, so that the three phase mains powers to the threephase load.

8. three phase mains guard method according to claim 6, which is characterized in that when the three phase mains protective device also Including the display module connecting with the control module, and in the phase sequence state, voltage status and current status, there are different Chang Shi, the three phase mains guard method further include:

Control phase sequence state, voltage status and current status that the display module shows the three phase mains.

9. three phase mains guard method according to claim 6, which is characterized in that when the three phase mains protective device also Including the working state indicating circuit connecting with the control module, the working state indicating circuit includes multiple indicator lights, When the Phase sequence detection module, voltage detection module and current detection module have respectively corresponded at least one indicator light, the side Method further include:

When the Phase sequence detection module, voltage detection module and current detection module detect phase sequence state, voltage status or electricity It is deposited in stream mode when abnormal, the state that the control module control detects is abnormal Phase sequence detection module, voltage detecting Module or the corresponding indicator light of current detection module are lighted or are extinguished.