CN202424597U

CN202424597U - Starting device for main electric motor of ship bow thruster

Info

Publication number: CN202424597U
Application number: CN2011204974391U
Authority: CN
Inventors: 宗许宁; 卢贤基
Original assignee: Dalian Maritime University
Current assignee: Dalian Maritime University
Priority date: 2011-12-05
Filing date: 2011-12-05
Publication date: 2012-09-05
Anticipated expiration: 2021-12-05

Abstract

The utility model discloses a starting device for a main electric motor of a ship bow thruster. According to the utility model, a thyristor excitation automatic regulating device is utilized to implement soft starting; for example, the YuKun ship bow thruster is separately supplied with power by a shaft driven generator; a terminal voltage of the generator is a terminal voltage of the electric motor; and if a certain method is adopted to ensure the terminal voltage of the generator equals to zero and then gradually boost the terminal voltage of the generator when the main electric motor is started, the rotating speed of the electric motor is also gradually accelerated when the voltage is risen so that the starting current can be always in a low state, and when a rated voltage is reached, the rotating speed of the electric motor also reaches a rated rotating speed, so that the soft starting of the nonimpact current is implemented. The starting method ensures equipment simple and only an exciter regulating device of the generator needs to be properly improved; and the starting current is always lower than a rated current of the electric motor, the starting process is stable, and basically, no current impact is generated for a power grid.

Description

Boats and ships bow thruster main motor starting device

Technical field

The present invention relates to electric motors, be specifically related to a kind of boats and ships bow thruster main motor starting device that utilizes the silicon controlled excitation automatic regulating apparatus to realize soft start.

Background technology

Thruster is a kind of special device that produces the boats and ships lateral thrust, can improve maneuverability and the fail safe of boats and ships when low speed, has improved the mobility of boats and ships.The general power of the main motor of thruster is all bigger, and for powerful motor, if across-the-line starting, then starting current is very big, will cause very big impact to electrical network.So it is necessary that the starting method of research motor is just wanted very much.Electric motor starting method commonly used at present has: 1, directly start.The advantage that directly starts is that equipment needed thereby is few, and Starting mode is simple, and cost is low.But for jumbo motor; The circuit and the transformer capacity that provide power supply on the one hand are difficult to satisfy the condition that motor directly starts; Powerful on the other hand starting current impacts electrical network and motor; Influence the useful life of motor, unfavorable to electrical network, so jumbo motor all will adopt reduced-voltage starting with the motor that can not directly start.2, the moving starting of stator string reactor or resistance: during starting, insert start-up circuit to reactor, excision after startup is accomplished.The advantage of this start mode is: equipment is simple, can reduce starting current.Shortcoming also clearly, this mode can only be used for underloading and starting under no load because starting current is when reducing, it is more that starting torque reduces.Also can in stator winding, seal in resistance, also can reduce starting current, but since guest performer's resistance on bigger power loss is arranged, especially to medium-sized, large-sized asynchronous motor is very uneconomical.3, single-circuit transformer reduced-voltage starting: adopt the autotransformer reduced-voltage starting, square proportional reduction of the starting current of motor and detent torque and its terminal voltage can obtain bigger detent torque under the situation of identical starting current.The advantage of autotransformer reduced-voltage starting is the direct labor to control, and also can control automatically with A.C. contactor, and durable in use, maintenance cost is low, is fit to all zero loads, the use of light-load starting asynchronous motor.Shortcoming is that manual operation will be disposed somewhat expensive auto-transformer case (from even compensator case); Automatically control will be disposed starting device and elements such as single-circuit transformer, A.C. contactor; Simultaneously, the setting of the mute time of single-circuit transformer point also is a difficult problem in the motor start-up process.4, Y-△ reduced-voltage starting: be applicable to that stator winding is the motor that △ connects, when starting, be connected into Y, speed transfers the △ operation during near rated speed to.The advantage of Y-△ reduced-voltage starting is need not acquire starting device, has control appliances such as starting switch or A.C. contactor just can realize, shortcoming is to be used for the motor that △ connects, and large-size asynchronous motor can not heavy load starting.5, soft start: soft starter is the soft start of a kind of current collection machine, soft stop, light-load energy saving and the kinds of protect function novel motor control assembly in one, is called Soft Starter abroad.Its main composition is the three-phase inverse parallel brake tube AC voltage regulator that is serially connected with between power supply and the controlled motor.The utilization diverse ways, the trigger angle of change thyristor is with regard to the output voltage of scalable thyristor voltage regulation circuit.In whole starting process, the output of soft starter is a level and smooth process of boosting, and up to the full conducting of thyristor, motor is worked under rated voltage.So, the starting method of motor is improved just show necessary.

Summary of the invention

The object of the present invention is to provide the rush of current in a kind of main motor starting process that solves thruster, the control starting current reduces the device to the boats and ships bow thruster main motor starting of the impact of electrical network.

Utilize the silicon controlled excitation automatic regulating apparatus to realize that soft start is that example adopts axle generator to supply power separately with the thruster of " educating enormous legendary fish, which could change into a roc " wheel bow; The terminal voltage of generator is the terminal voltage of motor; If starting during main motor we to adopt certain way to make the terminal voltage of generator earlier be zero, the generator voltage that raises gradually then, motor speed also raise gradually when voltage raise; Starting current will be under the low state always so; When reaching rated voltage, motor also reaches rated speed, thereby realizes the soft start of non-impact current.

Boats and ships bow thruster main motor starting device equipment of the present invention is simple, only needs the excitation unit adjusting device of generator is done suitable improvement; Starting current is lower than the motor rated current always, and start-up course is more steady, and electrical network is not had rush of current basically.

Description of drawings

Further set forth the present invention below in conjunction with accompanying drawing and case study on implementation.

Fig. 1 is the single line principle design block diagram of drive motors soft start of the present invention;

Fig. 2 is a single phase half wave controlled rectifier of the present invention;

Fig. 3 is No. 1 control circuit of the present invention;

Fig. 4 is No. 2 control circuits of the present invention.

Embodiment

Below in conjunction with embodiment boats and ships bow thruster main motor starting device of the present invention is described.

Embodiment 1.

Boats and ships bow thruster main motor starting device of the present invention utilizes the silicon controlled excitation automatic regulating apparatus to realize soft start.With the bow thruster of " educating enormous legendary fish, which could change into a roc " wheel is that example adopts axle generator to supply power separately, and the terminal voltage of generator is the terminal voltage of motor, if when the starting main motor we to adopt certain way to make the terminal voltage of generator earlier be zero; Generator voltage then gradually raises; Motor speed also raise gradually when voltage raise, and starting current will be under the low state, when reaching rated voltage always so; Motor also reaches rated speed, thereby realizes the soft start of non-impact current.

What this programme was inquired into is the G-M system that generator and thruster constitute; As shown in Figure 1; This device is designed by the inspiration of generator silicon controlled excitation automatic regulating apparatus, is formed in parallel by two excitation automatic regulating apparatuses, and each device is made up of rectification major loop and control circuit two parts; The rectification major loop is by armature winding, thyristor element, the fly-wheel diode of synchronous generator, compositions such as excitation winding; Control circuit is formed by measuring comparison, stabilizing circuit, phase-shift trigger unit etc.

Like Fig. 2 is the rectifying device circuit diagram, adopts element few, and circuit is simple; Single phase half wave controlled rectifier convenient for installation and maintenance, wherein the effect of fly-wheel diode is: when generator voltage instantaneous value decline zero passage, exciting current has been in and has reduced in the process gradually; To respond to an electromotive force at the excitation winding two ends; This electromotive force tries hard to stop reducing of exciting current, and diode-less D in the ifs circuit is then as long as this induced potential is higher than rectifier power source voltage; Because of bearing forward voltage, will continue conducting and out of control on the thyristor; Behind a parallelly connected diode D with excitation winding, then the induced potential of excitation winding (back-emf) can constitute the loop through D and makes exciting current continue circulation, so diode D claims fly-wheel diode.Between the afterflow period, thyristor turn-offs because of bearing reverse voltage, so appearance of negative voltage not.Fig. 3-4 is No. 1 control circuit, gathers voltage signal, mainly is in order to realize the function of automatic voltage adjustment; Given rated voltage when detecting generator voltage and set-point deviation is arranged, is given flip-flop circuit deviation signal through amplifying circuit relatively; Send control signal; Change the angle of flow of thyristor, increase or reduce exciting current, generator voltage is remained unchanged.

Like Fig. 3 is No. 2 control circuits, gathers current signal, and major function is to control the motor start-up electric current indirectly through the control exciting current.Given rated current signal, when detected current signal is not more than the rated current signal, the thyristor conducting, when greater than given signal, the angle of flow by deviation pass small thyristor makes it equal rated current.When axle was sent out to main mains supply, No. 2 device was excised through switch S 4, keeps the constant of set end voltage by a device.When the axle bill was solely supplied power for thruster, in the thruster motor start-up process, No. 1 device was excised through S3, No. 2 work.Existing soft start-up process is done explanation: when axle generator starts, set end voltage has reached 380V, and bus connection switch is separating brake, and the thruster system is ready; Press the thruster starting button, then S1 is closed, and magnet exciting coil is by short circuit, and set end voltage becomes the voltage that is produced by remanent magnetism; Delay time after several seconds, S2, the normal switching of S4 are closed, and S2 is normally closed to be opened, and the magnet exciting coil short circuit is disengaged; Generator has begun to press, and motor also begins starting, and in the motor start-up process, No. 1 device is not inserted.When starting current during, can not install regulating action No. 2, when starting current reaches rated current less than the motor rated current; No. 2 device is started working, and keeps starting current near rated current through the angle of flow of control thyristor, and motor speed raises gradually; After a period of time, electric current is again less than rated current, quits work for No. 2; Generator continues to boost, and when being raised to rated voltage, No. 1 device is inserted; The controller terminal voltage is constant, starts to finish No. 2 excitation adjusting devices of time-delay a period of time excision.

The above; Be merely the preferable embodiment of the present invention; But protection scope of the present invention is not limited thereto; Any technical staff who is familiar with the present technique field is equal to replacement or change according to technical scheme of the present invention and inventive concept thereof in the technical scope that the present invention discloses, all should be encompassed within protection scope of the present invention.

Claims

1. boats and ships bow thruster main motor starting device is characterized in that: utilize the silicon controlled excitation automatic regulating apparatus to realize soft start; Described starting device is formed in parallel by two excitation automatic regulating apparatuses, and each device is made up of rectification major loop and control circuit two parts, and the rectification major loop is by armature winding, thyristor element, the fly-wheel diode of synchronous generator, compositions such as excitation winding; Control circuit is formed by measuring comparison, stabilizing circuit, phase-shift trigger unit etc.; Adopt axle generator to supply power separately, the terminal voltage of generator is the terminal voltage of motor.