阅读说明：本技术 一种可物理断开的复合直流开关及开关方法 (Composite direct current switch capable of being physically disconnected and switching method ) 是由 赵笃良 郭鑫 史磊 龚晶晶 刘理想 骆廷亮 任强 郭建章 于 2018-08-30 设计创作，主要内容包括：本发明公开了一种可物理断开的复合直流开关及开关方法,该直流开关包括时序控制电路、主接触器J1、辅接触器J2和固体开关S1,所述时序控制单路输出的时序控制信号输入所述主接触器J1的线圈、所述辅接触器J2的线圈以及固体开关S1；所述主接触器J1的第一静触点和所述辅接触器J2的第一静触点连接,所述主接触器J1的第二静触点通过所述固体开关S1与所述辅接触器J2的第二静触点连接；所述主接触器J1的第一静触点和第二静触点为该直流开关的两个输出端,用于连接负载。该发明公开的技术方案实现了无触点切换,避免了直流高压接触器释放时的拉弧现象,显著提高开关通过电流的能力、延长开关寿命。(The invention discloses a composite direct current switch capable of being physically disconnected and a switching method, wherein the direct current switch comprises a time sequence control circuit, a main contactor J1, an auxiliary contactor J2 and a solid switch S1, wherein a time sequence control signal output by a time sequence control single circuit is input into a coil of the main contactor J1, a coil of the auxiliary contactor J2 and the solid switch S1; the first stationary contact of the main contactor J1 is connected with the first stationary contact of the auxiliary contactor J2, and the second stationary contact of the main contactor J1 is connected with the second stationary contact of the auxiliary contactor J2 through the solid switch S1; the first fixed contact and the second fixed contact of the main contactor J1 are two output ends of the direct current switch and are used for connecting a load. The technical scheme disclosed by the invention realizes non-contact switching, avoids the arc discharge phenomenon when the direct-current high-voltage contactor is released, obviously improves the current passing capability of the switch and prolongs the service life of the switch.)

1. A physically disconnectable compound DC switch, comprising: the direct current switch comprises a time sequence control circuit, a main contactor J1, an auxiliary contactor J2 and a solid switch S1, wherein a time sequence control signal output by a time sequence control single circuit is input into a coil of the main contactor J1, a coil of the auxiliary contactor J2 and the solid switch S1; the first stationary contact of the main contactor J1 is connected with the first stationary contact of the auxiliary contactor J2, and the second stationary contact of the main contactor J1 is connected with the second stationary contact of the auxiliary contactor J2 through the solid switch S1; the first fixed contact and the second fixed contact of the main contactor J1 are two output ends of the direct current switch and are used for connecting a load.

2. The physically disconnectable compound direct current switch according to claim 1, characterized in that: the solid switch S1 is a solid contactor, and the solid contactor is controlled to be turned on and off by the timing signal output by the timing control circuit.

3. The physically disconnectable compound direct current switch according to claim 1, characterized in that: the solid switch S1 comprises a triode Q and an isolation driving circuit, wherein the power supply end of the triode Q is connected with the second stationary contact of the auxiliary contactor J2, the control end of the triode Q is connected with the output end of the isolation driving circuit, and the low power supply end of the triode Q is connected with the second stationary contact of the main contactor J1; the isolation driving circuit is controlled by the time sequence signal output by the time sequence control circuit to output so as to enable the triode Q to be conducted and cut off.

4. The physically disconnectable compound direct current switch according to claim 1, characterized in that: the solid switch S1 comprises a Silicon Controlled Rectifier (SCR) and an isolation driving circuit, wherein the anode of the Silicon Controlled Rectifier (SCR) is connected with the second stationary contact of the auxiliary contactor J2, the control end of the Silicon Controlled Rectifier (SCR) is connected to the output end of the isolation driving circuit, and the cathode of the Silicon Controlled Rectifier (SCR) is connected to the second stationary contact of the main contactor J1; the isolation driving circuit is controlled by the time sequence signal output by the time sequence control circuit to output the time sequence signal to enable the SCR to be switched on and off.

5. A physically disconnectable compound direct current switch according to claim 1 or 2 or 3 or 4, characterized in that: the main contactor J1 and the auxiliary contactor J2 are electromagnetic contactors.

6. Method for switching a physically disconnectable composite direct current switch according to claim 1 or 2 or 3 or 4 or 5, characterized in that: the method comprises a composite switch switching-on step and a composite switch switching-off step, wherein the switching-on step specifically comprises the following steps:

step 1: loading a clock signal Ctrl and a Bias signal to the sequential control circuit, and enabling the sequential control circuit to output three paths of clock signals Ctrl _1, Ctrl _2 and Ctrl _ 3;

step 2: three clock signals Ctrl _1, Ctrl _2, and Ctrl _3 are respectively applied to the main contactor J1, the auxiliary contactor J2, and the solid switch S1;

and step 3: the auxiliary contactor J2, the solid switch S1 and the main contactor J1 are sequentially switched on under the control of clock signals Ctrl _2, Ctrl _3 and Ctrl _1, and after the main contactor J1 is pulled in, the current output by the physically-disconnected composite direct-current switch provides current for a load;

and 4, step 4: after the auxiliary contactor J2 and the solid switch S1 are continuously turned on for a certain time, Ctrl _2 and Ctrl _3 change to invalid signals, so that the auxiliary contactor J2 and the solid switch S1 are turned off; ctrl _1 is continuously effective, and the physically-disconnected composite direct-current switch continuously has output current;

the disconnection steps of the compound switch are as follows:

when the physically-disconnectable composite direct-current switch is in a continuous on state, clock signals Ctrl _2 and Ctrl _3 are changed from invalid to valid, the auxiliary contactor J2 is closed and the solid switch S1 is switched on, clock signal Ctrl _1 is changed from valid to invalid, the main contactor J1 is switched off, and current flows from the auxiliary contactor J2 and the solid switch S1; after a period of time, Ctrl _2 and Ctrl _3 change from active to inactive, the auxiliary contactor J2 and the solid switch S1 turn off, and the composite switch is turned off and is in an off state.

Technical Field

The present invention relates to a switch and a switching method, and more particularly, to a composite dc switch capable of being physically disconnected and a switching method.

Background

The direct current switch is also called a direct current fast switch or a direct current fast automatic switch, is an operation and protection, can perform switching-off and switching-on operations on a direct current motor, a rectifier unit, a direct current feeder line and the like in a direct current rated voltage 600-1500V circuit, and plays a role in trip protection when in short circuit, overload and reverse flow (reverse direction).

In the process of switching on and off the direct current switch, a direct current arc is generated, the arc current does not exceed a zero point in time and is non-periodically changed, and therefore the direct current arc is more difficult to extinguish than an alternating current arc. In general, a dc switch for extinguishing a dc arc has a high speed requirement in order to accelerate the breaking of an arc generated by a short circuit or an overload of a dc current.

At present, an electromagnetic contactor and a solid power switch are generally adopted for a direct current switch, wherein the electromagnetic contactor has the advantages of small contact connection voltage drop when being closed, physical disconnection when being disconnected and the like; however, when the electromagnetic contactor is subjected to arc pulling in the process of conducting and breaking, the higher the breaking direct-current voltage is, the more serious the arc pulling is; and has the defects of electric spark, short service life and the like. The solid power switch has the advantages of non-contact switching, no arc discharge, no electric spark, long service life and the like, but the solid power switch has the defects of current leakage and the like in the on-state voltage drop larger than that of an electromagnetic contactor and the off-state, and a radiator is required to be additionally arranged in the working process of the solid power switch, so that the structure of the direct current switch is complicated.

Disclosure of Invention

In order to solve the problems of the existing solid power switch and the electromagnetic contactor as the direct current switch, the invention aims to provide a composite direct current switch capable of being physically disconnected, which can be physically disconnected, realize non-contact switching, realize low on-voltage drop after the switch is connected and physically disconnected after the switch is disconnected.

The invention also aims to provide a switching method of the composite direct current switch capable of being physically disconnected. The method uses a solid power switch element to switch on or off a load to realize contactless switching; the contactor (mechanical switch) is used for bearing the steady-state process after the switch action, and the low on-voltage drop after the switch is switched on and the physical disconnection after the switch is switched off are realized.

The physically-disconnectable composite direct-current switch comprises a time sequence control circuit, a main contactor J1, an auxiliary contactor J2 and a solid switch S1, wherein a time sequence control signal output by a time sequence control single circuit is input into a coil of the main contactor J1, a coil of the auxiliary contactor J2 and the solid switch S1; the first stationary contact of the main contactor J1 is connected with the first stationary contact of the auxiliary contactor J2, and the second stationary contact of the main contactor J1 is connected with the second stationary contact of the auxiliary contactor J2 through the solid switch S1; the first fixed contact and the second fixed contact of the main contactor J1 are two output ends of the direct current switch and are used for connecting a load.

The direct current switch combines the contactor and the solid-state switch element, so the direct current switch integrates the advantages of the electromagnetic contactor and the solid-state switch element, realizes non-contact switching, improves the current passing capability of the contactor, avoids the adhesion and ablation of the contact of the contactor and prolongs the service life of the contactor; the solid switch does not need an additional radiator; the influence of the leakage current of the solid power switch on an application circuit is avoided. In addition, the direct current switch also avoids the arc discharge phenomenon when the direct current high-voltage contactor is released, improves the current passing capability of the switch and prolongs the service life of the switch; after release, the contactor bears voltage and is in a complete disconnection state, so that the non-contact switching of the pull-in and release of the composite contactor and the physical disconnection after the release are realized.

Specifically, the solid-state switch S1 is a solid-state contactor, and the solid-state contactor is controlled to be turned on and off by the timing signal output by the timing control circuit.

Specifically, the solid-state switch S1 includes a transistor Q and an isolation driving circuit, a power supply terminal of the transistor Q is connected to the second stationary contact of the auxiliary contactor J2, a control terminal of the transistor Q is connected to an output terminal of the isolation driving circuit, and a low power supply terminal of the transistor Q is connected to the second stationary contact of the main contactor J1; the isolation driving circuit is controlled by the time sequence signal output by the time sequence control circuit to output so as to enable the triode Q to be conducted and cut off.

Specifically, the solid switch S1 includes a silicon controlled rectifier SCR and an isolation driving circuit, an anode of the silicon controlled rectifier SCR is connected to the second stationary contact of the auxiliary contactor J2, a control end of the silicon controlled rectifier SCR is connected to an output end of the isolation driving circuit, and a cathode of the silicon controlled rectifier SCR is connected to the second stationary contact of the main contactor J1; the isolation driving circuit is controlled by the time sequence signal output by the time sequence control circuit to output the time sequence signal to enable the SCR to be switched on and off.

Specifically, the main contactor J1 and the auxiliary contactor J2 are electromagnetic contactors.

The switching method provided by the invention comprises a composite switch switching-on step and a composite switch switching-off step, wherein the switching-on step comprises the following specific steps:

step 1: loading a clock signal Ctrl and a Bias signal to the sequential control circuit, and enabling the sequential control circuit to output three paths of clock signals Ctrl _1, Ctrl _2 and Ctrl _ 3;

step 2: three clock signals Ctrl _1, Ctrl _2, and Ctrl _3 are respectively applied to the main contactor J1, the auxiliary contactor J2, and the solid switch S1;

and step 3: the auxiliary contactor J2, the solid switch S1 and the main contactor J1 are sequentially switched on under the control of clock signals Ctrl _2, Ctrl _3 and Ctrl _1, and after the main contactor J1 is pulled in, the current output by the physically-disconnected composite direct-current switch provides current for a load;

and 4, step 4: after the auxiliary contactor J2 and the solid switch S1 are continuously turned on for a certain time, Ctrl _2 and Ctrl _3 change to invalid signals, so that the auxiliary contactor J2 and the solid switch S1 are turned off; ctrl _1 is continuously effective, and the physically-disconnected composite direct-current switch continuously has output current;

the disconnection steps of the compound switch are as follows:

when the physically-disconnectable composite direct-current switch is in a continuous on state, clock signals Ctrl _2 and Ctrl _3 are changed from invalid to valid, the auxiliary contactor J2 is closed and the solid switch S1 is switched on, clock signal Ctrl _1 is changed from valid to invalid, the main contactor J1 is switched off, and current flows from the auxiliary contactor J2 and the solid switch S1; after a period of time, Ctrl _2 and Ctrl _3 change from active to inactive, the auxiliary contactor J2 and the solid switch S1 turn off, and the composite switch is turned off and is in an off state.

The method uses a solid power switch element to switch on or off a load, thereby realizing non-contact switching; the contactor (mechanical switch) is used for bearing the steady-state process after the switch action, and the low on-voltage drop after the switch is switched on and the physical disconnection after the switch is switched off are realized.

The invention has the beneficial effects that: the advantages of the electromagnetic contactor and the solid switch element are integrated, so that the non-contact switching is realized, the current passing capability of the contactor is improved, the contact adhesion and ablation of the contactor are avoided, and the service life of the contactor is prolonged; the arc discharge phenomenon when the direct-current high-voltage contactor is released is avoided, the current passing capability of the switch is improved, and the service life of the switch is prolonged; after release, the contactor bears voltage and is in a complete disconnection state, so that the non-contact switching of the pull-in and release of the composite contactor and the physical disconnection after the release are realized.

Drawings

Fig. 1 is one of the schematic circuit diagrams of the dc switch provided in the present invention;

FIG. 2 is a second schematic circuit diagram of the DC switch provided by the present invention;

fig. 3 is a third schematic circuit diagram of the dc switch provided in the present invention;

FIG. 4 is a timing diagram illustrating the control of the present invention;

in the figure, the connection end marks are the same, which indicates that the connection relationship exists between the connection end marks and the control power supply, Com in the figure is a common end of the control power supply, Ctrl-1 and Ctrl-2 are respectively connected with control signals of a main contactor J1 and an auxiliary contactor J2, and Ctrl-3 is a control signal of a solid switch S1; ctrl is a control signal applied by an external control circuit; the Bias signal is used as a Bias power supply to provide power for the composite direct current switch.

Detailed Description

The claimed invention is described in further detail herein with reference to specific embodiments and accompanying drawings.

As shown in fig. 1-3, the claimed technical solution of the present invention is a physically disconnectable composite dc switch, which includes a timing control circuit, a main contactor J1, an auxiliary contactor J2 and a solid switch S1, wherein a timing control signal outputted by a timing control single circuit is inputted to a coil of the main contactor J1, a coil of the auxiliary contactor J2 and the solid switch S1; the first fixed contact of the main contactor J1 is connected with the first fixed contact of the auxiliary contactor J2, and the second fixed contact of the main contactor J1 is connected with the second fixed contact of the auxiliary contactor J2 through a solid switch S1; the first stationary contact and the second stationary contact of the main contactor J1 are two output ends A, B of the direct current switch and are used for connecting a load.

The main contactor J1 and the auxiliary contactor J2 adopt electromagnetic contactors, and the solid switch S1 can adopt the following structures:

the first method comprises the following steps: the solid switch S1 is a solid contactor S1, which is controlled by the timing signal output by the timing control circuit to turn on and off.

Secondly, the solid switch S1 comprises a triode Q and an isolation driving circuit, wherein the power supply end of the triode Q is connected with the second static contact of the auxiliary contactor J2, the control end of the triode Q is connected with the output end of the isolation driving circuit, and the low power supply end of the triode Q is connected with the second static contact of the main contactor J1; the isolation driving circuit controls the output of the isolation driving circuit by the time sequence signal output by the time sequence control circuit to enable the triode Q to be conducted and cut off. The triode Q is a field effect transistor, the drain electrode of the triode Q is connected with the second static contact of the auxiliary contactor J2, the source electrode of the triode Q is connected to the second static contact of the main contactor J1, and the grid electrode of the triode Q is connected with the output end of the isolation driving circuit.

Thirdly, the solid switch S1 comprises a Silicon Controlled Rectifier (SCR) and an isolation driving circuit, the anode of the Silicon Controlled Rectifier (SCR) is connected with the second stationary contact of the auxiliary contactor J2, the control end of the Silicon Controlled Rectifier (SCR) is connected to the output end of the isolation driving circuit, and the cathode of the Silicon Controlled Rectifier (SCR) is connected to the second stationary contact of the main contactor J1; the isolation driving circuit controls the output of the isolation driving circuit by the time sequence signal output by the time sequence control circuit to enable the SCR to be switched on and off.

The switching method of the physically disconnectable composite dc switch claimed in the present invention is described in detail with reference to the timing diagram shown in fig. 4.

The on and off processes of the DC switch provided by the invention are respectively as follows:

1. the switching-on process of the compound switch comprises the following steps:

1) ctrl-2 is effective, and the auxiliary contactor J2 is closed;

2) ctrl-3 is active, solid switch S1 is on, and output terminals a and B are on;

3) ctrl-1 is effective, the main contactor J1 is closed, current outputs are arranged at two ends of the output ends A and B, and a path for increasing load current is started;

4) ctrl-3 is inactive, solid switch S1 is off;

5) ctrl-2 is deactivated and auxiliary contactor J2 is released;

6) ctrl-1 is continuously effective, and the main contactor J1 keeps attracting;

the closing process is completed and A, B is connected by main contactor J1 to provide current to the load connected across A, B.

2. The disconnection process of the combination switch (before the main contactor J1 keeps closed, the auxiliary contactor J2 releases, the solid switch S1 is turned off)

1) Ctrl-2 is effective, and the auxiliary contactor J2 is closed;

2) ctrl-3 is active, solid switch S1 is on;

3) when Ctrl-1 is invalid, the main contactor J1 is disconnected, and the load current flows through the auxiliary contactor J2 and the solid switch S1;

4) ctrl-3 is inactive, solid switch S1 is off, and the load current is cut off;

5) ctrl-2 is deactivated and the auxiliary contactor J2 is released.

The disconnection process is completed, A, B is in a physical disconnection state, and no current is output from both ends A, B.

The composite direct current switch capable of being physically disconnected has the remarkable characteristics that the solid switch undertakes the switching process when the composite direct current switch is closed and released, so that the non-contact switching is realized, the arc discharge phenomenon when the direct current high-voltage contactor is released is avoided, the current passing capability of the switch is remarkably improved, and the service life of the switch is prolonged; after release, the contactor bears voltage and is in a complete disconnection state, so that the contactless switching of attraction and release of the composite contactor and the physical disconnection after release can be realized.