The DC electromagnet control circuit
Technical field
The utility model relates to magnetizing of DC electromagnet and degaussing control, refers to a kind of DC electromagnet control circuit particularly.
Technical background
Conventionally known to one of skill in the art, employed circuit is controlled in magnetize and the degaussing of existing DC electromagnet, as shown in Figure 1, it is by resistance (R1, R2, R3, R4, R5, R6), electric capacity (C1, C2, C3), diode (D1, D2, D3), contactor (MCA, MCB), switch S 1, fuse (F1, F2, F3) and electromagnet L 1 form, wherein, the contact of contactor (MCA1, MCA2, MCA3, MCA4) is the contact of same contactor MCA, and the contact of another winding tentaculum (MCB1, MCB2, MCB3) is the contact of another contactor MCB.In actual use, this circuit can't guarantee to disconnect above-mentioned two contactors when the electric current of electromagnet L1 is zero, thereby causes that contactor frequently strikes sparks, and then damages contactor.The electrical technology personnel improved it afterwards.Control circuit for electromagnet after the improvement, as shown in Figure 2, it is by resistance (R7, R8, R9, R 10), electric capacity (C4, C5, C6), diode (D4, D5, D6) and contactor MCC, switch S 2, fuse (F4, F5, F6) and electromagnet L2 form, wherein, the contact of contactor (MCC1, MCC2) is the contact of contactor MCC.After the improvement, though overcome the frequent sparking of contactor and then damaged the technical problem of contactor, in order to limit the terminal voltage of electromagnet coil, the resistance of resistance R 10 is can not value excessive, thereby causes the discharge time of electromagnet L2 long.The electromagnet L2 degaussing time in this circuit prolongs greatly like this.Production efficiency is significantly descended.
Summary of the invention
The purpose of this utility model will provide a kind of DC electromagnet control circuit exactly, and this circuit can reduce the damage frequency of contactor, and can shorten the degaussing time of electromagnet.
For realizing this purpose, the DC electromagnet control circuit that the utility model is designed, comprise DC power supply, diode, electromagnet L3 and contactor MCD, wherein, the positive pole of described DC power supply links to each other with described electromagnet L3 one end by the first normally open contact MCD1 of described contactor MCD, the other end of described electromagnet L3 links to each other with the positive pole of the first diode D9, the negative pole of the first diode D9 inserts the negative pole of described DC power supply, the negative pole of the second diode D11 links to each other with described electromagnet L3 one end, the positive pole of the second diode D11 links to each other with the other end of described electromagnet L3 by the second normally open contact MCD2 of contactor MCD, be connected with capacitor C10 between the positive pole of the negative pole of the first diode D9 and the second diode D11, and the positive pole of this capacitor C10 links to each other with the negative pole of the first diode D9, the negative pole of capacitor C10 links to each other with the positive pole of the second diode D11, and the coil series connection back of switch S 3 and contactor MCD is inserted between the positive pole and negative pole of DC power supply.
Further, the positive pole of the 3rd diode D10 is connected in the negative pole of capacitor C10, and the negative pole of the 3rd diode D10 is connected in the positive pole of capacitor C10.
Described DC power supply is obtained after by diode rectification by three-phase alternating-current supply, wherein, the first normally open contact MCD1 of described contactor MCD is connected with first of three-phase alternating-current supply by the 4th diode D7, the first normally open contact MCD1 of described contactor MCD also is connected with second of three-phase alternating-current supply by the 5th diode D8, and the described first diode D9 negative pole is connected with the third phase of three-phase alternating-current supply.
First of described the 4th diode D7 and three-phase alternating-current supply is connected with the first fuse F7 between mutually, second of described the 5th diode D8 and three-phase alternating-current supply is connected with the second fuse F8 between mutually, is connected with the 3rd fuse F9 between the coil of described contactor MCD and the third phase of three-phase alternating-current supply.
Further, between first resistance R 11 and the 7 series connection back accesses of first capacitor C three-phase alternating-current supply first phase and three-phase alternating-current supply second phase with the second fuse F8 with the first fuse F7, between three-phase alternating-current supply second phase and the three-phase alternating-current supply third phase with the 3rd fuse F9 of access with the second fuse F8, the 3rd resistance R 13 and the 3rd capacitor C 9 are connected between three-phase alternating-current supply first phase and the three-phase alternating-current supply third phase with the 3rd fuse F9 of back access with the first fuse F7 after second resistance R 12 and 8 series connection of second capacitor C.
The utility model has the advantages that: the setting in electromagnetic circuit by above capacitor and diode, make the damage frequency of contactor and the degaussing time of electromagnet obviously shorten, improved production efficiency greatly.
Description of drawings
Fig. 1 is a kind of circuit diagram of existing DC electromagnet control circuit;
Fig. 2 is another kind of existing DC electromagnet control circuit circuit diagram;
Fig. 3 is the circuit diagram of DC electromagnet control circuit;
Fig. 4 changes corresponding circuit diagram after the polarity of DC power supply for the DC electromagnet control circuit.
Embodiment
The utility model is described in further detail below in conjunction with the drawings and specific embodiments:
DC electromagnet control circuit as shown in Figure 3, it comprises DC power supply, diode, electromagnet L3 and contactor MCD, wherein, the positive pole of described DC power supply links to each other with described electromagnet L3 one end by the first normally open contact MCD1 of described contactor MCD, the other end of described electromagnet L3 links to each other with the positive pole of the first diode D9, the negative pole of the first diode D9 inserts the negative pole of described DC power supply, the negative pole of the second diode D11 links to each other with described electromagnet L3 one end, the positive pole of the second diode D11 links to each other with the other end of described electromagnet L3 by the second normally open contact MCD2 of contactor MCD, be connected with capacitor C10 between the positive pole of the negative pole of the first diode D9 and the second diode D11, and the positive pole of this capacitor C10 links to each other with the negative pole of the first diode D9, the negative pole of capacitor C10 links to each other with the positive pole of the second diode D11, and the coil series connection back of switch S 3 and contactor MCD is inserted between the positive pole and negative pole of DC power supply.Cause danger for fear of the reverse polarity charging overtension, the positive pole of the 3rd diode D10 is connected in the negative pole of capacitor C10, and the negative pole of the 3rd diode D10 is connected in the positive pole of capacitor C10.
In the technique scheme, described DC power supply is obtained after by diode rectification by three-phase alternating-current supply, wherein, the first normally open contact MCD1 of described contactor MCD is connected with first of three-phase alternating-current supply by the 4th diode D7, the first normally open contact MCD1 of described contactor MCD also is connected with second of three-phase alternating-current supply by the 5th diode D8, and the described first diode D9 negative pole is connected with the third phase of three-phase alternating-current supply.Above-mentioned the 4th diode D7 and the 5th diode D8 constitute alternating current to galvanic conversion.
For circuit being realized first of described the 4th diode D7 of short-circuit protection and three-phase alternating-current supply is connected with the first fuse F7 between mutually; second of described the 5th diode D8 and three-phase alternating-current supply is connected with the second fuse F8 between mutually, is connected with the 3rd fuse F9 between the coil of described contactor MCD and the third phase of three-phase alternating-current supply.
In the technique scheme, in order to realize inhibition to circuit noise, between first resistance R 11 and the 7 series connection back accesses of first capacitor C three-phase alternating-current supply first phase and three-phase alternating-current supply second phase with the second fuse F8 with the first fuse F7, between three-phase alternating-current supply second phase and the three-phase alternating-current supply third phase with the 3rd fuse F9 of access with the second fuse F8, the 3rd resistance R 13 and the 3rd capacitor C 9 are connected between three-phase alternating-current supply first phase and the three-phase alternating-current supply third phase with the 3rd fuse F9 of back access with the first fuse F7 after second resistance R 12 and 8 series connection of second capacitor C.
Introduce operation principle of the present utility model below, three phase mains is behind overcurrent fuse, its three-phase alternating-current supply first is converted into direct current with respect to the three-phase alternating-current supply third phase through the 4th diode D7 and the 5th diode D8 respectively mutually with three-phase alternating-current supply second mutually, when Closing Switch S3 first, the second normally open contact MCD2 closure of the first normally open contact MCD 1 of contactor MCD and contactor MCD, electric current is through the first normally open contact MCD1 of contactor MCD, electromagnet L3, the second normally open contact MCD2 of the second diode D11 and contactor MCD, the 3rd diode D10 constitutes the loop, and this moment, power supply magnetized to electromagnet L3.
When switch S 3 disconnects, the first normally open contact MCD1 of contactor MCD and the second normally open contact MCD2 of contactor MCD disconnect, and the other end of the electric current among the electromagnet L3, the end through electromagnet L3, the first diode D9, capacitor C10, the second diode D11 and electromagnet L3 constitutes the loop.Electromagnet L3 degaussing this moment, and convert the magnetic field energy of electromagnet L3 to electric field energy and be stored among the capacitor C10.
When Closing Switch S3 once more, the second normally open contact MCD2 closure of the first normally open contact MCD1 of contactor MCD and contactor MCD, electric current is through the positive pole of power supply, the first negative pole formation loop of touching the second normally open contact MCD2, capacitor C10 and the power supply of MCD1, electromagnet L3, contactor MCD of contactor, and this moment, power supply and capacitor C10 magnetized to electromagnet L3 jointly.When nearly 0.5 volt of capacitor C10 discharge and reverse charge, the first diode D9 conducting, after this magnetic field of electromagnet L3 is kept by power supply.
As having changed the polarity of DC power supply, this circuit is can structure constant, only need put upside down the first diode D9, the 3rd diode D10, the second diode D11 and capacitor C10 polarity and get final product, as shown in Figure 4.Operation principle roughly the same.