CN204231234U - A kind of forcing press soft starting device - Google Patents

Abstract

The utility model discloses a kind of soft starting device of forcing press, comprise soft starter, major loop, control loop, described main circuit power end is connected to soft starter terminal 1L1, 3L2, 5L3, motor terminal is connected to soft starter terminal 2T1, 4T2, 6T3, the external bypass contactor KM1 of major loop receives soft starter terminal B1 respectively, the inlet wire side of B2 and B3 and soft starter terminal 2T1, 4T2, 6T3, described control loop wiring is: alternating current 220V 50Hz power supply is connected to soft starter terminal 1 by 2 pole circuit breaker Q F209, on 2, soft starter terminal is function ground connection.The utility model has the advantage of: the smooth start and the operation that achieve motor, effectively reduce the starting current of forcing press, can reduce distribution capacity, avoid electrical network increase-volume to invest.Decrease a dynamic stress of forcing press and load equipment simultaneously, extend the useful life of forcing press and relevant device.

Description

A kind of forcing press soft starting device

Technical field

The utility model relates to machine field, particularly relates to forcing press soft starting device.

Background technology

Asynchronous motor, with the feature of its excellent performance and Maintenance free, is widely used in all trades and professions.But due to greater impact electric current (being generally the 5-8 of Ie doubly) will be produced when it starts, simultaneously comparatively large owing to playing dynamic stress, the useful life of load equipment is reduced.The method of the reduced voltage starting adopted traditionally has the conversion of star triangle, from lotus root step-down reduced voltage starting.Although these two kinds of start modes all can reduce starting current, but the stepping switching after reduced voltage starting process completes and the moment adding total head, the peak current (secondary pulse electric current) of several times rated current will be produced, this electric current will impact distribution system, the destructive dynamic torque simultaneously produced can cause the mechanical shock of pump motor, very harmful to the rotor, idler gear etc. of motor, and supply line's power consumption is increased.

Soft starter put goods on the market in late 1970s and the beginning of the eighties.It is a kind of Electric Machine Control equipment integrating soft start, soft stop, light-load energy saving and multifunction protection.In whole starting process, realizing the starting current level and smooth without impacting, and the various parameters in starting process can be regulated according to the characteristic of motor load, as cut-off current, starting time etc.In addition, it also has multiple to electric motor protecting, and this just fundamentally solves many drawbacks of traditional decompression starting equipment.

The operation principle of soft starter: soft starter adopts three-phase anti-parallel thyristor as adjuster, is accessed between power supply and motor stator.This circuit is as Three-phase full-bridge rectification circuit.When using soft starter starting motor, the full conducting of thyristor, in mechanical property when motor is operated in rated voltage, realizes smooth starting, reduces starting current, avoids starting overcurrent tripping.When motor reaches rated revolution, starting process terminates, soft starter replaces the thyristor of having finished the work from employing bypass contactor, rated voltage is provided for motor runs well, to reduce the thermal losses of thyristor, extend the useful life of soft starter, improve its operating efficiency, make again electrical network avoid harmonic pollution.Soft starter also provides soft stop function simultaneously, and soft stop is contrary with Soft Start-up Process, and voltage reduces gradually, and rotating speed drops to zero gradually, avoids the torque shock ends that free parking causes.Soft starter has three kinds of start modes: voltage ramp starting-can obtain maximum output torque; Current limit starting-effectively can limit starting current; Crawl-test run debug function can be realized.

When motor starting, reduce the voltage being added to motor stator winding, the starting current of motor can be reduced.General reduced voltage starting refers to that the change in voltage that motor is added in motor stator winding in starting process is abrupt transients; And soft start uses regulator within the starting time of regulation, automatically starting voltage is risen continuously, smoothly until reach rated voltage.

The mechanical property of asynchronous motor can represent with n=f (M).Its characteristic curve as shown in Figure 1 to Figure 3.In as can be seen from Fig. 1 to Fig. 3, according to general reduced voltage starting, suppose starting voltage U=0.5Ue, then torque during motor starting is 0.25Mn, torque when namely starting only has 1/4 of motor breakdown torque.If at this moment voltage U is increased to motor rated voltage Ue, then the torque of motor just jumps to Mn from 1/4 quickly, such starting process be jump, rough, should not adopt the occasion of manufacturing technique requirent smooth start.And soft start voltage from initial voltage continuously and smoothly increases.From Fig. 1 to 3, the continuous of that curve continuously smooth of 0.5Ue moves in parallel to the right, always steadily to during that curve co-insides of rated voltage Ue, so the torque of motor will increase smoothly until till when torque is maximum Mn, starting process also just terminates.Like this, in starting process, the torque of motor is level and smooth instead of jumps, and starting process is stable.The relatively various start modes of asynchronous motor, can find out when motor direct-on-line starting, maximum to the impact of electrical network, attack time is also the longest, and normally used reduced voltage starting (star triangular decompression starter) is though smaller to the impact of electrical network, but owing to relating to a coil voltage handoff procedure, occur the unfavorable link of secondary pulse, the starting current that soft start has an impact owing to setting army's electrical network at prestart, therefore non-impact current, minimum on the impact of electrical network, and the impact of starting torque can be eliminated.

Utility model content

Technical problem to be solved of the present utility model is the starting current providing a kind of effective reduction forcing press, decrease a dynamic stress of forcing press and load equipment simultaneously, extend the soft starting device of the forcing press in the useful life of forcing press and relevant device.

The utility model solves the problems of the technologies described above by the following technical solutions: a kind of soft starting device of forcing press, comprise soft starter, major loop, control loop, described main circuit power end is connected to soft starter terminal 1L1, 3L2, 5L3, motor terminal is connected to soft starter terminal 2T1, 4T2, 6T3, the external bypass contactor KM1 of major loop receives soft starter terminal B1 respectively, the inlet wire side of B2 and B3 and soft starter terminal 2T1, 4T2, 6T3, described control loop wiring is: alternating current 220V 50Hz power supply is connected to soft starter terminal 1 by 2 pole circuit breaker Q F209, on 2, soft starter terminal is function ground connection.

Optimize, the internal control power supply that the soft starting device of forcing press is selected, soft starter terminal 8,9 short circuit, a termination soft starter terminal 4,5 of auxiliary relay KAO, another termination soft starter terminal 11, auxiliary relay KAO connects PLC.

Optimize, described soft starter has 3 groups of output relays able to programme, auxiliary relay K1 receives on the first group relay Chang Kaiduan 13,14, auxiliary relay K2 receives on the second group relay Chang Kaiduan 16,17, auxiliary relay K3 receives on the 3rd group relay Chang Kaiduan 19,20, and analog output terminal 23,24 is received on PLC.

The utility model has the advantage of: the smooth start and the operation that achieve motor, it effectively reduces the starting current of forcing press, can reduce distribution capacity, avoids electrical network increase-volume to invest.Decrease a dynamic stress of forcing press and load equipment simultaneously, extend the useful life of forcing press and relevant device.Soft stop function efficiently solves the parking surge problems of inertia system, is that traditional startup equipment cannot realize.

Accompanying drawing explanation

Fig. 1 is across-the-line starting, star/triangle starting and the soft start different manifestations curve chart at motor voltage (V).

Fig. 2 is across-the-line starting, star/triangle starting and the soft start different manifestations curve chart at electric current (I).

Fig. 3 be across-the-line starting, star/triangle start and soft start motor torque (M) different manifestations curve chart.

Fig. 4 is the structure principle chart of the utility model forcing press soft starting device.

Embodiment

Below in conjunction with accompanying drawing, the utility model is described in detail.

The electrical wiring mode that employing the utility model carries out soft start is as follows: be first major loop wiring, main circuit power end be connected to soft starter terminal 1L1,3L2,5L3; Motor terminal is connected to soft starter terminal 2T1,4T2,6T3; Then external bypass contactor KM1 is received respectively the inlet wire side of terminal B1, B2 and B3, and soft starter terminal 2T1,4T2,6T3.Then be control loop power supply and control loop wiring, alternating current 220V 50Hz power supply is connected on soft starter terminal 1,2 by 2 pole circuit breaker Q F209 (6A).Soft starter terminal 3 is function ground connection, and received by cable with on the earth point of soft starter close together, cable should be short as far as possible.

It is the internal control power supply selected in the present embodiment, therefore soft starter terminal 8,9 short circuit, then one is used to realize starting and stop to control with auxiliary auxiliary relay KAO, a termination soft starter terminal 4,5 of auxiliary relay KAO, another termination soft starter terminal 11.

Auxiliary relay KAO is by PLC program control.

Soft starter selected by the utility model has 3 groups of output relays able to programme, is received by auxiliary relay K1 on the first group relay Chang Kaiduan 13,14, is arranged to start complete function by soft starter; Auxiliary relay K2 is received on the second group relay Chang Kaiduan 16,17, be arranged to the motor overload function under event by soft starter; Auxiliary relay K3 is received on the 3rd group relay Chang Kaiduan 19,20, be arranged to the unbalance function of three-phase under event by soft starter.Finally analog output terminal 23,24 is received on the Analog input mModule of PLC, be arranged to current of electric function by soft starter, realize on PLC, monitor current of electric situation of change.

Operation principle is as follows: when electric motor starting, PLC control relay KAO closes, start soft starter, then by the angle of flow of electronic circuit control thyristor, the terminal voltage of motor is raised gradually with the speed of setting, be raised to full voltage always, make motor realize no surge start to the process controlling flexible starter for electric motor.When motor starting completes and reaches rated voltage, three-phase bypass contactor KM1 is closed, and motor directly drops into operation of power networks.Forcing press is unloaded when starting, then when normally running, maintain required low voltage, the power factor of motor is raised, efficiency increases.When motor stopping, also by controlling the angle of flow of thyristor, making terminal voltage of motor slowly be reduced to 0, thus realizing soft stop.When the situation that motor appearance is transshipped or three-phase is unbalance, soft starter can pass through auxiliary relay K2 and K3 immediately, and deliver to inside PLC, control KAO, realizes soft stop.

Debugging is as follows with the process of test run: conscientiously check after the installation of control of soft cabinet, whether correct check wiring by design drawing.The electronic devices such as thyristor permit no. megger test, can only check the insulation situation of thyristor in soft starter with digital multimeter high resistant shelves.New soft starter (during cold conditions) often organizes measured resistance value between thyristor input and output terminal should indicate about 1.3M, alternate while not connecing control loop (alternate), relatively measured resistance value should be designated as infinity.Before motor is connected with soft starter, the state of insulation of motor and cable must be checked with 500V insulation resistance tester.Only have insulation resistance to comply with relevant regulations, just permit motor and set the technical parameters such as start mode, initial voltage, starting time and downtime.Then forcing press starting test and parameter optimization is carried out.

Forcing press power of motor: 132KW, adopt star triangular decompression starter mode before not using soft starter, the switching controls of motor star triangle is realized by the time relay, reignition impulse current is large, and comparatively serious to the damage of main contactor main contacts, long-time running is gone down, the consequences such as burning of contact may be caused, and serious to electric network influencing, adopt forcing press soft starting device of the present utility model, achieve smooth start and the operation of motor.

According to the actual conditions of forcing press, the soft starter of the PST300-600-70 type that ABB AB can be selected to produce, this soft starter designs based on nearest microprocessor technology, stops for the soft start and soft stop realizing squirrel-cage.It has also attached the electric motor protecting function of several advanced person, has multiple integrated protection and warning function, almost all faults can be detected, and display it.

The foregoing is only the preferred embodiment that the utility model is created; do not create in order to limit the utility model; the any amendment done within all spirit of creating at the utility model and principle, equivalent to replace and improvement etc., all should be included within protection range that the utility model creates.

Claims (3)

1. the soft starting device of a forcing press, it is characterized in that: comprise soft starter, major loop, control loop, described main circuit power end is connected to soft starter terminal 1L1, 3L2, 5L3, motor terminal is connected to soft starter terminal 2T1, 4T2, 6T3, the external bypass contactor KM1 of major loop receives soft starter terminal B1 respectively, the inlet wire side of B2 and B3 and soft starter terminal 2T1, 4T2, 6T3, described control loop wiring is: alternating current 220V 50Hz power supply is connected to soft starter terminal 1 by 2 pole circuit breaker Q F209, on 2, soft starter terminal is function ground connection.

2. the soft starting device of a kind of forcing press as claimed in claim 1, it is characterized in that: the internal control power supply that the soft starting device of forcing press is selected, soft starter terminal 8,9 short circuit, the one termination soft starter terminal 4,5 of auxiliary relay KAO, another termination soft starter terminal 11, auxiliary relay KAO connects PLC.

3. the soft starting device of a kind of forcing press as claimed in claim 1, it is characterized in that: described soft starter has 3 groups of output relays able to programme, auxiliary relay K1 receives on the first group relay Chang Kaiduan 13,14, auxiliary relay K2 receives on the second group relay Chang Kaiduan 16,17, auxiliary relay K3 receives on the 3rd group relay Chang Kaiduan 19,20, and analog output terminal 23,24 is received on PLC.