CN2891470Y

CN2891470Y - Electric control device for frequency conversion unit

Info

Publication number: CN2891470Y
Application number: CN 200620096538
Authority: CN
Inventors: 李江泽
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-04-28
Filing date: 2006-04-28
Publication date: 2007-04-18
Anticipated expiration: 2016-04-28

Abstract

The utility model relates to an electric control device particularly relating to a frequency changer set electric control device, which comprises an alternating current contactor 1KM, 2KM, 3KM, a control button 1SB, 2SB, a time relay KT, a heat relay KP, a breaker KF and a phase sequence failure protecting relay K, wherein the frequency changer set is started with a star firstly, after prolonging time, a triangle is automatically working and the starting current becomes weak, and during the starting no intermediate frequency is outputted, and the protection of the phase failure, wrong phase sequence, over current, abnormal three-phase voltage of the frequency changer set is provided by the time relay KT, the heat relay KP, the breaker KF and the phase sequence failure protecting relay K. The utility model solves the questions that the machine unit can not protect itself when the traditional control device loses voltage, the starting current is strong, during the period of the starting the intermediate frequency outputs, when the machine unit loses phase, three-phase power supply can not be cut off in time and results in burning down of the frequency- changer. The utility model is applicable to the electric control of the all kinds of frequency changer set.

Description

Frequency conversion unit electrical control gear

Affiliated technical field:

The utility model relates to a kind of electrical control gear, particularly a kind of frequency conversion unit electrical control gear.

Background technology:

For protecting vibrating head and frequency conversion unit normally to move, need improve control circuit, increase control device.But all there are some following shortcomings in traditional frequency conversion unit electrical control gear because of the reason in its design:

1, unit can not self-protecting after the voltage decompression, causes phase sequence incorrect, and vibrating head is reversed, thereby damages vibrating head.

2, unit is in starting process, and intermediate frequency just has output, if this moment, the vibrating head circuit was connected, then bringing onto load starting of unit causes very big pressure drop, makes that unit can't normal starting, and damages unit coil and other electric elements.

3, do not have open phase protection, when unit runs into faults such as losing phase, stall or excess load, can not in time cut off three phase supply, cause frequency convertor to burn.

4, short-circuit protection is unreliable.

Summary of the invention:

The purpose of this utility model is: provide that a kind of phase failure to the frequency conversion unit, phase sequence are incorrect, overcurrent, three-phase voltage is undesired shields; zero intermediate frequency output in the starting process; vibrating head and frequency conversion unit are normally moved, and safe and reliable frequency conversion unit electrical control gear.

The utility model is to realize above-mentioned purpose by the following technical solutions:

This frequency conversion unit electrical control gear is made of switching circuit and control circuit, and switching circuit is made up of circuit breaker KF and thermal relay KP, is connected on the power supply circuits; It is characterized in that: described control circuit is by A.C. contactor 1KM, 2KM, 3KM, control button 1SB, 2SB, and time relay KT and phase sequence phase failure relay K form; The fixed end of control button 1SB is connected with the U1 of supply line, and the fixed end of the moved end of control button 1SB, control button 2SB and A.C. contactor 1KM often leave auxiliary contact 1KM ₁The fixed end connect; The moved end of control button 2SB, A.C. contactor 1KM often leave auxiliary contact 1KM ₁Moved end, the normally closed auxiliary contact 2KM of A.C. contactor 2KM ₁Fixed end, time relay KT fixed end, A.C. contactor 3KM often open auxiliary contact 3KM ₁Fixed end, A.C. contactor 1KM often open auxiliary contact 1KM ₂The fixed end connect; The normally closed auxiliary contact 2KM of A.C. contactor 2KM ₁The moved end be connected with coil one end of time relay KT; The moved end of time relay KT contact and the normally closed auxiliary contact 2KM of A.C. contactor 2KM ₂, A.C. contactor 3KM coil be connected; A.C. contactor 3KM often leaves auxiliary contact 3KM ₁Moved end, A.C. contactor 1KM often open auxiliary contact 1KM ₂Moved end, the normally closed auxiliary contact KP of thermal relay KP ₁Fixed end, the normally closed auxiliary contact 3KM of A.C. contactor 3KM ₂The fixed end be connected the normally closed auxiliary contact KP of thermal relay KP ₁The moved end be connected the normally closed auxiliary contact 3KM of A.C. contactor 3KM with coil one end of A.C. contactor 1KM ₂The moved end be connected with coil one end of A.C. contactor 2KM; The other end of the coil of A.C. contactor 3KM and the coil of A.C. contactor 1KM is connected with the fixed end of phase sequence phase failure relay K; After being connected, the moved end of the coil of the coil of time relay KT, A.C. contactor 2KM, phase sequence phase failure relay K is connected with the W1 of supply line; Three main contacts 1KM of A.C. contactor 1KM ₃Be connected in series with the U1 of supply line, V1, W1; Three main contacts 2KM of A.C. contactor 2KM ₃Be attempted by motor M both sides U2, X respectively, on the circuit of V2, Y and W2, Z; Three main contacts 3KM of A.C. contactor 3KM ₃Be connected on the end of circuit X, Y, Z and intermediate frequency generator three main contacts 3KM of A.C. contactor 3KM ₃The moved end link together.

The utility model compared with prior art has following beneficial effect:

1, three-phase voltage undesired, when phase sequence is incorrect, the frequency conversion unit can not start.Solved the problem that causes vibrator rollback corruption vibrator because of the unit counter-rotating.

2, change motor into star and triangle comprehensively starts, start the frequency conversion unit with star earlier,, be changed to triangle operation work automatically, thereby reduce the excessive shortcoming of starting current by time-delay.It is bigger to have overcome the triangle starting current, and the user does not notice that the electric current that frequency conversion unit bringing onto load is started is bigger sometimes, thereby damages the deficiency of frequency conversion unit.

3, the frequency conversion unit is in running, if the phase failure avoided the single phasing of motor to burn motor autostop in 2 seconds.

4, the frequency conversion unit is in running, if short circuit, circuit breaker is with automatic powered-down; If overcurrent, thermal relay will disconnect main power source.

5, ground connection good reliability.Adopt zero connection protection, reduced the ground voltage (1.732 times of voltages have descended) of intermediate frequency power supply; If leaky has appearred in vibrating head, will produce a bigger short circuit current, control device will in time be cut off the electricity supply, and guarantee that vibrator does not move under long-term electric leakage state, guarantees operator's personal safety.

Description of drawings:

Fig. 1 is the circuit theory diagrams of frequency conversion unit electrical control gear;

Fig. 2 is the structural representation of frequency conversion unit electrical control gear.

Among the figure: 1KM, 2KM, 3KM, A.C. contactor, 1SB, 2SB, control button, KT, the time relay, KP, thermal relay, KF, circuit breaker, K, phase sequence phase failure relay, TD, binding post, M, motor, GA, intermediate frequency generator.

Embodiment:

This frequency conversion unit electrical control gear is by A.C. contactor 1KM, 2KM, 3KM, control button 1SB, 2SB, and time relay KT, thermal relay KP, circuit breaker KF and phase sequence phase failure relay K and binding post TD form switching circuit and control circuit.Switching circuit is made up of circuit breaker KF and thermal relay KP, is connected on the power supply circuits.Control circuit is by A.C. contactor 1KM, 2KM, 3KM, control button 1SB, 2SB, and time relay KT and phase sequence phase failure relay K form.The fixed end of control circuit by control button 1SB is connected with the U1 of supply line, and the moved end of the coil by time relay KT, the coil of A.C. contactor 2KM, phase sequence phase failure relay K is connected and then is connected with the W1 of supply line.

The course of work of this frequency conversion unit electrical control gear is: at first, energized, three-phase voltage is normal, and phase sequence is correct, and phase sequence phase failure relay K connects.Press control button 2SB again, A.C. contactor 3KM begins action, and M is connected into star with motor; A.C. contactor 3KM often leaves auxiliary contact 3KM ₁Connect A.C. contactor 1KM, the 380V power supply enters motor M, and motor M is in the star starting.Three main contacts 3KM of A.C. contactor 3KM ₄The magnetizing coil of while short circuit intermediate frequency generator GA, in starting process, intermediate frequency generator GA no-output.In starting process, time relay KT on-delay prolonged disconnected break of contact A.C. contactor 3KM after 3 seconds, finished motor M starting process.The normally closed auxiliary contact 3KM of A.C. contactor 3KM ₂Connect A.C. contactor 2KM, motor M is converted to the triangle operation; Simultaneously, the energising of intermediate frequency generator GA magnetizing coil is thrown and is encouraged, and intermediate frequency generator GA exports normal 200V, 125HZ intermediate frequency power supply.

Over current fault occurs as the frequency conversion unit, thermal relay KP plays overcurrent protection, the normally closed auxiliary contact KP of thermal relay KP ₁Disconnect A.C. contactor 1KM, motor M shuts down.

If after the phase failure, the electric elements among the phase sequence phase failure relay K will play a protective role, and after 2 seconds, phase sequence phase failure relay K disconnects, and promptly entire circuit disconnects.

If short circuit, the electric elements among the circuit breaker KF disconnect circuit breaker, and promptly entire circuit disconnects.

If the electric leakage of vibrating head rod shell, its comprehensive line will be got back on the unit neutral line by earth connection, form a short circuit current, and the air switch of machine line terminal box cuts out automatically, and promptly entire circuit disconnects.

Claims

1, a kind of frequency conversion unit electrical control gear, it is made of switching circuit and control circuit, and switching circuit is made up of circuit breaker KF and thermal relay KP, is connected on the power supply circuits; It is characterized in that: described control circuit is by A.C. contactor 1KM, 2KM, 3KM, control button 1SB, 2SB, and time relay KT and phase sequence phase failure relay K form; The fixed end of control button 1SB is connected with the U1 of supply line, and the fixed end of the moved end of control button 1SB, control button 2SB and A.C. contactor 1KM often leave auxiliary contact 1KM ₁The fixed end connect; The moved end of control button 2SB, A.C. contactor 1KM often leave auxiliary contact 1KM ₁Moved end, the normally closed auxiliary contact 2KM of A.C. contactor 2KM ₁Fixed end, time relay KT fixed end, A.C. contactor 3KM often open auxiliary contact 3KM ₁Fixed end, A.C. contactor 1KM often open auxiliary contact 1KM ₂The fixed end connect; The normally closed auxiliary contact 2KM of A.C. contactor 2KM ₁The moved end be connected with coil one end of time relay KT; The moved end of time relay KT contact and the normally closed auxiliary contact 2KM of A.C. contactor 2KM ₂, A.C. contactor 3KM coil be connected; A.C. contactor 3KM often leaves auxiliary contact 3KM ₁Moved end, A.C. contactor 1KM often open auxiliary contact 1KM ₂Moved end, the normally closed auxiliary contact KP of thermal relay KP ₁Fixed end, the normally closed auxiliary contact 3KM of A.C. contactor 3KM ₂The fixed end be connected the normally closed auxiliary contact KP of thermal relay KP ₁The moved end be connected the normally closed auxiliary contact 3KM of A.C. contactor 3KM with coil one end of A.C. contactor 1KM ₂The moved end be connected with coil one end of A.C. contactor 2KM; The other end of the coil of A.C. contactor 3KM and the coil of A.C. contactor 1KM is connected with the fixed end of phase sequence phase failure relay K; After being connected, the moved end of the coil of the coil of time relay KT, A.C. contactor 2KM, phase sequence phase failure relay K is connected with the W1 of supply line; Three main contacts 1KM of A.C. contactor 1KM ₃Be connected in series with the U1 of supply line, V1, W1; Three main contacts 2KM of A.C. contactor 2KM ₃Be attempted by motor M both sides U2, X respectively, on the circuit of V2, Y and W2, Z; Three main contacts 3KM of A.C. contactor 3KM ₃Be connected on the end of circuit X, Y, Z and intermediate frequency generator three main contacts 3KM of A.C. contactor 3KM ₃The moved end link together.