CN105253751A - Three-phase electric phase shifter used for providing stability for elevator - Google Patents

Abstract

The present invention relates to a phase shifter for providing stable three-phase power to an elevator, comprising: an input unit for inputting a single-phase AC signal composed of first and second input terminals and first and second input lines connected to them ; rectify the single-phase AC signal input through the single-phase AC input part into a rectifying circuit part of a DC signal; use two switches to control the rectified DC signal in the rectifying circuit part, and adjust the 3rd output line and the other two The phase of the voltage between the two output lines, the inverter circuit part that outputs the third AC signal of the required phase; the inverter circuit part connected with the third contact between the two switches of the inverter circuit part an output unit composed of a third output terminal and first and second output terminals connected to the first and second input lines; and a controller for controlling the inverter circuit unit.

Description

Phase shifter for providing stable three-phase power to lifts

technical field

The present invention relates to a phase shifter that converts the phase of a single-phase input power supply to a three-phase in order to transmit stable three-phase power to an elevator. More specifically, it relates to a In the case of single-phase AC power input through the drive motor input power of the device, elevator, etc., which lifts or pulls goods by cables, it can also convert the input single-phase AC into a three-phase phase shifter, so as to A phase shifter that supplies stable three-phase AC power to drive the motor.

Background technique

Generally speaking, the elevators used in industrial sites are devices that use motors to wind or unwind steel wires to raise and lower heavy objects.

As an example of the prior art in this field, there can be mentioned a simple elevator for carrying goods, people, etc. up and down when constructing an outer wall of a building as shown in FIG. 1 . With reference to Fig. 1, the simple and easy elevator of prior art carries out lifting action by steel cable 4. Safety devices 3 and the lifting device 10 for simple elevators of the present invention are installed on both sides of the elevator frame 2 configured to be able to carry goods, and are provided with a control box 6 for controlling their actions. The elevator uses a lifting device 10, and the auxiliary steel cable 5 only passes through the safety device 3. The simple elevator 1 for conveying goods constituted in this way is turned on/off (ON/OFF) by operating the switch of the control box 6, so that the safety device 3 performs the opening and closing action, and the lifting device 10 for the simple elevator is driven by the motor 10-1. The positive and negative rotation is carried out, and the lifting is carried out through the steel cable 4 and the auxiliary steel cable 5.

Generally, the simple elevator 1 uses a single-phase motor as a motor for driving a steel wire (refer to FIG. 2 ). Since simple elevators used in industrial sites operate with excessive loads as needed, there is a problem that the life of the motor is shortened due to overload. Therefore, for stabilization, the power of motors used in simple lifts, hangers, cargo lifting devices, etc. used in industrial sites needs to be 380V. However, conventional motors of elevators used in this field use 220V single-phase motors, and there is a problem of supplying unsafe electric power. In this way, using 220V will cause power shortage, so it is necessary to use three-phase 380V. However, the problem is that the motor of the elevator used outdoors as conventional industrial use cannot use three-phase current. The place where three-phase is used does not necessarily have to be a power motor in an industrial site, and it is also widely applicable to general building switchboards and the like. In three-phase current, the current has 3 phases. With three phases, the safety of power supply can be ensured.

The reason for using three phases is firstly to obtain constant power. In single phase, voltage is electricity that is passed up and down as a sinusoidal waveform. However, in three phases, power is delivered at a constant magnitude. The most common use of generated electricity is as power for electrical equipment, most of which are motors. Three phases make it possible to move the motor in the desired direction also by the motor's starting torque without special devices. Compared with single-phase, three-phase power transmission and distribution is more economical. It is possible to reduce loss or reduce construction costs during delivery from a remote power station to a general factory or home. When making it three-phase by connecting one more strand than single-phase (two strands), it is possible to transmit 73% more power by increasing copper by 50%. Or three phases can be transmitted with 75% less copper wire than when the same power is transmitted through a single phase. In general, a 220V single-phase power supply is used as a general household power supply, but a three-phase power supply with high power efficiency is more suitable for factories and large commercial facilities that require large power. The single-phase motors popular at home and abroad in the past have the problem of wear of the centrifugal force switch contacts when starting up, and sometimes sparks can cause fires. Compared with three-phase motors, they have the disadvantage of high production costs. Therefore, even in places where only single-phase power is used, the elevator motor driven in a three-phase manner in order to realize the input of single-phase power, the phase shifter that converts single-phase AC input into three-phase AC and supplies it to the three-phase motor demand is increasing day by day.

As an example of the prior art in which a single-phase AC power is input to drive a three-phase motor driven by a three-phase AC, Korean Laid-Open Utility Model No. 20-2011-0009510 can be cited.

3 is a schematic structural block diagram of a three-phase motor disclosed in Korean Laid-Open Utility Model No. 20-2011-0009510.

Referring to FIG. 3 , a conventional three-phase motor driven by inputting a single-phase AC will be briefly described. When a single-phase 220V AC power supply is input to the three-phase drive motor 20, it is necessary to perform phase conversion to convert the single phase into three phases. In this case, a simple phase conversion unit 50 can be formed at the input end of the three-phase drive motor to convert the single-phase AC input into three-phase, which can be used as the input of the three-phase drive motor 20 . The phase conversion unit 50 is configured in such a way that the single-phase power supply connection terminals R, S input to the drive motor 20 are connected to two of the connection terminals U, V, W of the three-phase drive motor 20. A phase conversion capacitor 51 is connected between one of the two phases connected to the single-phase power supply and the remaining three-phase drive motor 20 connection terminal not connected to the single-phase power supply.

However, in the case of such conventional technology, although the structure is simple, there is a problem that it is necessary to improve the stability of the output three-phase signal. Therefore, in order to more stably drive a three-phase motor, there is an increasing demand for a novel phase shifter that skillfully processes an input signal of a single-phase AC power supply to output a three-phase AC signal with a stable three-phase phase.

prior art literature

patent documents

Patent Document 1: Republic of Korea Laid-Open Utility Model No. 20-2011-0009510.

Contents of the invention

The problem to be solved by the invention

The present invention is made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a phase shifter for an elevator that is installed in an elevator, receives a single-phase AC power supply, and outputs a stable three-phase AC power supply.

Solution to the problem

In order to achieve the above-mentioned purpose, the phase shifter for providing stable three-phase power to the elevator of the present invention is characterized in that it includes: the first and second input terminals 311, 312 and the first Composed of the second input lines 313 and 314, the input unit 310 that inputs the single-phase AC signal; the rectifier circuit unit 320 that rectifies the single-phase AC signal input through the single-phase AC input unit 310 into a DC signal; In the way of controlling the gate of the device, two switches 331 and 332 composed of a pair of transistors control the DC signal rectified in the rectifier circuit part 320 to output a signal, and the output control signal is passed through the third contact 333 and the current Inductor 355 that induces a voltage in proportion to the amount of change is output to the third output line 353, and an inverter circuit that outputs a third AC signal having a required voltage phase difference between the other two output lines 351 and 352 part 330; the third output terminal 354 connected to the third contact point 333 formed between the two switches 331 and 332 of the inverter circuit part 330 and the first and second input lines 313 and 314 The first and second output terminals 356, 357 connected to form the second output line 352 and the third output line 353 form an output unit 350 that applies a three-phase AC signal with a phase difference of 120°; and controls the The controller 340 of the output section.

Invention effect

An effect of the present invention is that it is possible to provide a phase shifter for an elevator that receives a single-phase AC power supply and outputs a stable three-phase AC power supply.

Description of drawings

Fig. 1 is the perspective view to the simple and easy elevator that conventional lifting device is installed;

Fig. 2 is the front view of conventional single-phase motor for simple elevator;

Fig. 3 is a schematic structural block diagram of a conventional three-phase motor;

Fig. 4 is the front view to the elevator drive motor that the phase shifter of the present invention is installed;

Fig. 5 is the input/output wiring block diagram of the phase shifter of the present invention;

Fig. 6 is the structural block diagram of the phase shifter of an embodiment of the present invention;

FIG. 7 is a circuit diagram of a phase shifter according to an embodiment of the present invention.

Explanation of reference signs

2: Lift frame 3: Safety device

4: Cable 5: Auxiliary cable

6: Control box 10: Lifting device

10-1: Motor 20: Conventional drive motor

50: Phase conversion unit 51: Phase conversion capacitor

100: shell 200: drive motor

300: phase shifter 310: input unit

311: 1st input terminal 312: 2nd input terminal

313: 1st input line 314: 2nd input line

310: input unit 320: rectification circuit unit

321: 1st contact point 322: 2nd contact point

323: 1st capacitor 324: 2nd capacitor

325: 1st diode 326: 2nd diode

330: Inverter circuit unit 331: First switch

332: 2nd switch 333: 3rd contact

340: controller 350: output unit

351: 1st output line 352: 2nd output line

353: 3rd output line 354: 3rd output terminal

355: Sensor 356: 1st output terminal

357: 2nd output terminal 358: 3rd capacitor

359: 4th capacitor.

detailed description

The present invention can be modified variously, and can have various embodiments, and only specific embodiments are shown in the drawings, and will be described in detail in the following detailed description. However, this does not limit the present invention to specific embodiments, and it should be understood that all changes, equivalents, and substitutions within the spirit and technical scope of the present invention are included.

When describing each drawing, similar reference numerals are used for similar components. Terms such as first and second can be used to describe various components, but the components are not limited to the terms. These terms are used only for the purpose of distinguishing one constituent element from other constituent elements.

For example, the term "and/or" includes a combination of multiple related items or one item among multiple related items.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as those generally understood by those skilled in the art.

Terms that are the same as those defined in commonly used dictionaries should be interpreted as meanings that are consistent with the meanings of words and sentences in the related art. As long as they are not clearly defined in this application, they should not be interpreted as ideal or overly formal. mean.

Hereinafter, a phase shifter for supplying three-phase AC power to a three-phase drive motor of an elevator according to an embodiment of the present invention will be described with reference to the drawings.

Fig. 4 is a front view of an elevator driving motor equipped with a phase shifter of the present invention.

With reference to Fig. 4, the three-phase drive motor 200 that is arranged on the hoisting device of the elevator and winds or unclamps the steel wire is connected with three strands of electric wires for supplying three-phase power, and the three strands of electric wires are independently arranged on the The output of the external phase shifter 300 that drives the motor 200 is connected. The input terminal of the phase shifter 300 is connected to an external power supply through a wire to input a single-phase AC signal, and the output terminal outputs a three-phase AC signal with a phase difference of 120° to the driving motor 200 .

FIG. 5 is a block diagram showing input/output wiring of the phase shifter of the present invention.

Referring to FIG. 5 , as an embodiment of the present invention, the input of the phase shifter 300 is single-phase AC220V, and the three-phase AC220V is output after passing through the phase shifter, which is used as a three-phase AC input for driving the three-phase drive motor 200.

Fig. 6 is a structural block diagram of a phase shifter according to an embodiment of the present invention.

Referring to Fig. 6, the phase shifter of the present invention is composed of: an input unit 310 for inputting a single-phase AC signal; a rectifying circuit unit 320 for rectifying the single-phase AC signal input through the single-phase AC input unit 310 into a DC signal The output voltage of the DC signal rectified in the rectification circuit part 320 is controlled by two switches 331 and 332 composed of a pair of transistors, and the inverter circuit part 330 that adjusts the phase of the output voltage; The 3rd output terminal 354 connected to the inverter circuit part 330 and the 1st and 2nd output terminals 356, 357 connected to the 1st and 2nd input lines 131, 314 of the phase shifter 300 are constituted, and the three-phase drive motor 200 , an output unit 350 that outputs a three-phase AC voltage with a phase difference of 120°; and a controller 340 that controls the inverter circuit unit 330 .

FIG. 7 is a circuit diagram of a phase shifter according to an embodiment of the present invention.

With reference to Fig. 7, phase shifter of the present invention comprises: by the 1st and the 2nd input terminal 311,312 and the 1st and the 2nd input wire 313,314 that are connected with them constitute, input the input part 310 of single-phase AC signal; Two switches 331 and 332 composed of a pair of transistors are used to control the gates of the controller to control the DC signal rectified in the rectification circuit part 320 to output a signal, and the output control signal is passed through the third contact 333 is output to the third output line 353 via the inductor 355 that induces a voltage in proportion to the amount of change in current, and outputs a third AC signal having a required voltage phase difference between the other two output lines 351 and 352 Inverter circuit part 330; by the 3rd output end 354 that is connected with the 3rd contact point 333 between two switches 331, 332 that constitute described inverter circuit part 330 and with described 1st and 2nd input Lines 313, 314 are connected to form the first and second output terminals 356, 357 on the second output line 352 and the third output line 353, and apply the output part 350 of a three-phase AC signal with a phase difference of 120°; And a controller 340 that controls the inverter circuit unit 330 .

The rectifier circuit unit 320 includes: a pair of capacitors 323 and 324 connected together to the first contact 321 connected to the first input line 313; and a second contact connected to the second input line 314 together. 322 of a pair of rectifier diodes 325,326. The inverter circuit unit 330 is composed of two switches 331 and 332 connected together to a third contact point 333 and composed of a pair of transistors whose gates are controlled by the controller 340 .

The controller 340 sends a control signal to the gates of the two switches 331, 332 of the inverter circuit part 330 to control the two switches 331, 332, thereby obtaining the first, second and third output Three-phase output voltages with the desired phase difference between terminals 356, 357, 354. The output unit 350 includes an inductor 355 between the third contact 333 and the third output end 354, a third capacitor 358 between the first output end 356 and the third output end 354, and a third capacitor at the third output end. A fourth capacitor 359 is provided between 354 and the second output terminal 357 , and a three-phase AC voltage having a phase difference of 120° is applied to the driving motor 200 .

Claims (4)

1. A phase shifter for providing stable three-phase power to the elevator, the phase shifter (300) enables the input to the hoisting device of the elevator to wind or loosen the single drive motor (200) of the steel wire Phase conversion of phase-to-phase AC power, characterized in that, The phase shifter (300) is connected in the following manner: the phase shifter (300) is independently arranged in the elevator with the driving motor (200) of the lifting device of the elevator, and the phase shifter ( The input end of 300) is connected with the external power supply through electric wire and input single-phase alternating current signal, and the output end of this phase shifter (300) will have the three-phase alternating current signal output of 120 ° phase difference to the drive motor (200) input terminal, The phase shifter includes: The input part (310) is composed of the first and second input terminals (311, 312) and the first and second input lines (313, 314) connected to them, and inputs a single-phase AC signal; a rectifier circuit unit (320), rectifying the single-phase AC signal input through the single-phase AC input unit (310) into a DC signal; The inverter circuit section (330) controls the DC signal rectified in the rectification circuit section (320) by two switches (331, 332) composed of a pair of transistors in such a manner that the gate is controlled by the controller. Output signal, the output control signal is output to the third output line (353) through the third contact (333) through the inductor (355) that induces voltage in proportion to the change of current, and output on the other two output lines (351, 352) have a third AC signal with a required voltage phase difference; The output unit (350) is composed of a third output terminal (354) connected to the third contact point (333) formed between the two switches (331, 332) of the inverter circuit unit (330) and a third output terminal (354) connected to the The first and second input lines (313, 314) are connected to form the first and second output terminals (356, 357) on the second output line (352) and the third output line (353), and the application has Three-phase AC signals with a phase difference of 120°; and A controller (340) controls the inverter circuit unit (330). 2. The phase shifter for providing stable three-phase power to the elevator according to claim 1, wherein the rectification circuit part (320) comprises: a pair of capacitors (323, 324), connected together to the first contact (321) connected to the first input line (313); and A pair of rectifier diodes (325, 326) are connected together to a second contact point (322) connected to the second input line (314). 3. The phase shifter for providing stable three-phase power to elevators according to claim 1, wherein: The controller (340) sends control signals to the gates of the two switches (331, 332) of the inverter circuit part (330) to control the two switches (331, 332), thereby obtaining Three-phase output voltage with a required phase difference between the 1st, 2nd and 3rd output lines. 4. The phase shifter for providing stable three-phase power to elevators according to claim 1, wherein: The output part (350) has an inductor (355) between the third contact point (333) and the third output end (354), and an inductor (355) between the first output end (356) and the third output end (354). A third capacitor (358) is provided between them, and a fourth capacitor (359) is provided between the third output terminal (354) and the second output terminal (357).