KR102574474B1 - Low-noise inverter of bldc motor for driving fire screen of stage device in performance hall - Google Patents

Abstract

A low-noise inverter of a BLDC motor for driving a fire curtain of a performance hall stage device according to the present invention is a BLDC motor inverter for driving a fire barrier separating a stage and seats in a performance hall in the event of a fire, comprising: a commercial power supply for inputting AC power; a power conversion module for converting AC power supplied from the commercial power supply unit into DC power; a SIC module that receives DC power supplied from the power conversion module and converts it into power required by the BLDC motor; An MCU controlling the speed and torque of the BLDC motor by switching a carrier frequency to a 114KHZ band through a pulse width modulation (PWM) variable voltage; A plurality of Hall sensors that are formed inside the BLDC motor and detect the position information of the rotor with current flowing elements when a magnetic field is received; by removing resonance noise, the audible frequency band generated when the BLDC motor is driven It has the effect of eliminating electrical noise.

Description

Low-noise inverter of BLDC motor for driving fire screen of stage device in performance hall

The present invention relates to a low-noise inverter of a BLDC motor for driving a fire curtain of a stage device in a performance hall, and more particularly, to protect seats from a fire on the stage, a border decoration or device separating the seats and the stage when a fire occurs on the stage It blocks the opening of the proscenium, which corresponds to the arch, to prevent flame or smoke from entering the audience and provides power to open and close the theater stage fire screen, which can be lifted and lowered to extend the time for audiences to evacuate. It relates to a low-noise inverter of a BLDC motor for driving a fire screen of a stage device for controlling a BLDC motor.

A conventional BLDC motor is driven with a PWM carrier frequency of 4KHZ to 20KHZ.

As it is driven at the above-described frequency, the conventional BLDC motor has a problem in that electrical noise causes the generation of high-frequency sound within an audible frequency.

That is, the conventional BLDC motor has a problem of generating resonance noise as vibration occurs in the coil when magnetism is generated in the coil during driving.

Republic of Korea Patent Registration No. 10-2269480 (2021. 06. 21)

In order to solve the above-described problems, the present invention is a fire prevention of a performance hall stage device that can remove resonance by suppressing vibration generated in a coil by vibration when driving a BLDC motor by switching to a carrier frequency band of 114KHZ band An object of the present invention is to provide a low-noise inverter of a BLDC motor for driving a film.

In order to achieve the above object, the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention is an AC power source A commercial power supply unit for inputting; A power conversion module for converting the AC power supplied from the commercial power supply unit into DC power; a SIC module that receives DC power supplied from the power conversion module and converts it into power required by the BLDC motor; An MCU controlling the speed and torque of the BLDC motor by switching a carrier frequency to a 114KHZ band through a pulse width modulation (PWM) variable voltage; It is characterized in that it includes; a plurality of Hall sensors that are formed inside the BLDC motor and sense the position information of the rotor as an element through which current flows when a magnetic field is received.

In addition, in order to achieve the above object, the power conversion module of the low-noise inverter of the BLDC motor for driving the fire curtain of the theater stage apparatus according to the present invention includes a bridge diode for converting AC power supplied from the commercial power supply into DC power; a capacitor that is charged by receiving the DC power converted by the bridge diode; a resistor connected in parallel between the bridge diode and the condenser so that the condenser is charged by bypassing the DC power converted in the bridge diode; and an electromagnetic contactor that, when the capacitor is charged, turns from an OFF state to an ON state so that the inverted current is offset.

In addition, in order to achieve the above object, the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention is formed between the MCU and the SIC module and has a built-in boost circuit to increase the output voltage of the MCU It is characterized in that it further comprises; gate driver for converting the voltage level to the gate voltage of the SIC module.

In addition, in order to achieve the above object, the MCU of the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention measures the signal generated during rotation of the BLDC motor instead of the encoder by the hall sensor In the process, it is characterized in that the accumulated error is removed by treating the accumulated error as a zero point due to the occurrence of an encoding numerical error due to the distortion of the corresponding signal.

In addition, in order to achieve the above object, the MCU of the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention measures the temperature of the BLDC motor in real time or periodically so that the temperature does not rise above the threshold Characterized in monitoring the BLDC motor. A low-noise inverter of BLDC motors for driving fire screens in theater stage devices.

In order to achieve the above object, the MCU of the low-noise inverter of the BLDC motor for driving the fire curtain of the theater stage device according to the present invention receives the amount of current according to the driving of the BLDC motor measured by the shunt resistance, and how much the corresponding BLDC motor It is characterized by determining whether it has a moment (force) of

The low-noise inverter of the BLDC motor for driving the fire curtain of the theater stage device according to the present invention removes the resonance sound by switching the carrier frequency to the 114KHZ band, thereby eliminating electrical noise in the audible frequency band generated when the BLDC motor is driven there is

In addition, the low-noise inverter of the BLDC motor for driving the fire curtain of the performance hall stage device according to the present invention treats the accumulated error of the distorted encoding value as zero point in the process of measuring the signal generated during the rotation of the BLDC motor by the hall sensor It has the effect of obtaining a precise position value.

In addition, the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention is economical due to the above-mentioned effects and uses a highly efficient BLDC motor for the theater stage device, thereby reducing installation and maintenance costs There is a derived effect.

1 is a block diagram of a low-noise inverter of a BLDC motor for driving a fire curtain of a theater stage device according to the present invention.
2 is a diagram showing the location of a hall sensor of a BLDC motor for driving a fire curtain at a performance hall stage according to the present invention and a graph of detected waveforms.

The terms or words used in this specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to explain their invention in the best way. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical spirit of the present invention.

Therefore, since the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, they can be substituted at the time of this application It should be understood that there may be many equivalents and variations.

Hereinafter, with reference to the accompanying drawings, a low-noise inverter of a BLDC motor for driving a fire curtain of a stage device for separating a stage and seats of a performance hall in the event of a fire according to the present invention will be described in detail.

1 is a block diagram of a low-noise inverter of a BLDC motor for driving a fire curtain of a theater stage device according to the present invention.

As shown in FIG. 1, the low-noise inverter of the BLDC motor for driving the fire screen of the theater stage device according to the present invention includes a commercial power supply unit 100, a power conversion module 200, a SIC module 300, 300, and a BLDC motor 400, a shunt resistor (SHUNT RESISTOR: 500), a hall sensor 600, an MCU 700, and a drum 800.

The commercial power supply unit 100 is AC power corresponding to 220V or 380V supplied from the switchboard to the concert hall.

The power conversion module 200 converts AC power supplied from the commercial power supply unit 100 into stable DC power and supplies it to the SIC power semiconductor 300 .

More specifically, the power conversion module 200 includes a bridge diode 210, a resistor 220, an electromagnetic contactor 230, and a capacitor 240.

The bridge diode 210 converts AC power supplied from the commercial power supply unit 100 into DC power.

The resistor 220 is connected in parallel between the bridge diode 210 and the capacitor 240 so that an instantaneous inverted current is supplied when the DC power converted in the bridge diode 210 is charged into the capacitor 240. Accordingly, the capacitor 240 may be damaged, which is alleviated.

That is, the DC power converted by the bridge diode 210 is not directly applied to the condenser 240, but is slowly charged in the condenser 240 for a short time of about 500 m/sec via the resistor 220. It is possible to prevent the capacitor 240 from being damaged by an instantaneous overcurrent.

As described above, when charging of the condenser 240 via the resistor 220 is completed, the magnetic contactor 230 in an OFF state is turned on, and the inverted current is offset, thereby canceling the bridge diode 210. ), current is stably supplied to the capacitor 240.

The capacitor 240 is connected to the drain terminal of the transistor of the SIC module 300, and the charged DC current is supplied through the drain terminal of the SIC module 300, which is a power semiconductor.

The SIC module 300 receives DC power supplied from the condenser 240 and converts it into power required by the BLDC motor 400.

That is, the SIC module 300 converts AC power required for the BLDC motor 400 from DC power supplied by being connected to the gate terminal.

The SIC module 300 has excellent material properties compared to silicon, so it can withstand about eight times higher voltage, can flow up to 100 times more current, has excellent thermal conductivity, and has a small leakage current, so it is a semiconductor device suitable for energy saving.

In particular, since the SIC module 300 has a high operating temperature of 500 to 600° C. and excellent thermal conductivity, it is easy to cool even if the heat transfer area is small.

For reference, Si-based MOSFETs and IGBT power semiconductors, which are mainstream, have a problem in that when the voltage blocking performance is doubled, the on-resistance increases five times, so that high withstand voltage characteristics and high frequency characteristics cannot be sufficiently satisfied.

As shown in FIG. 2, the BLDC motor 400 has a permanent magnet located in the center as a rotor, and a total of six strands of three iron core coils are formed, each with two strands, and when current flows through the corresponding coil Using the principle of being a magnet, the rotor is driven by the principle that the rotor rotates by passing current two strands at a position (phase) difference of 120 degrees.

That is, the BLDC motor 400 is a mechanism configured by rotating a rotor, which is a magnet corresponding to a field, and sequentially switching drive coils disposed around it. The permanent magnet of the electrons and the attractive or repulsive force act. The repulsive force acts on the same pole, and the attractive force acts on the other pole to rotate.

The speed of the BLDC motor 400 is controlled through PWM (Pulse With Modulation: Pulse Width Modulation) voltage/current under the control of the MCU 700.

The MCU 700 can control the speed and available torque of the BLDC motor 400 by applying a variable voltage to the motor winding through PWM (Pulse With Modulation) and switching the carrier frequency to the 114 KHZ band.

The Hall sensor 600 is a magnetic field sensor and is an element through which current flows when a strong magnetic field is received, and detects positional information about the location of the magnetic field, that is, the location of the rotor, so that the MCU 700 can check it.

That is, the Hall sensor 600 is formed between stators as shown in FIG. 2A, and detects where the position of the rotor is and transmits it to the MCU 700, the MCU 700 detects the Hall sensor By applying a current to the coil with the positional information of the rotor detected by (600), attractive and repulsive forces can be generated between the rotor and the fixing thread so that the rotor can rotate.

In the present invention, the hall sensor 600 is used to drive so as to be controlled according to the field angle of the BLDC motor 400.

The hall sensor 600 measures the signal generated when the BLDC motor 400 rotates and replaces the encoder, and at this time, an encoding numerical error may occur due to distortion of the signal. It is difficult to control the exact position due to errors in the lifting distance of the motor.

As a method for removing the accumulated error, the magnet of the drum 800 is positioned so that the accumulated error of the encoding value can be removed when the drum 800 rotates once.

That is, the MCU 700 can remove the accumulated error by using (handling) the accumulated error that may occur in the entire driving distance of the BLDC motor for driving the fire curtain on the stage of the performance hall, which is a lifting equipment, as a zero point.

For example, when the gear ratio between the motor and the drum is 1:100, the amount of rotation of the motor is generated at the corresponding gear ratio, and 100 pulses must be input for the drum 800 to rotate once, but 101 pulses are input 1 pulse is captured as an error.

In the above, the case where the drum 800 rotates once was mentioned as an example, but when the drum 800 rotates hundreds or thousands of times, the cumulative error increases, so that the lifting of the fire curtain on the stage of the performance hall cannot be performed smoothly.

In order to solve this problem, it is preferable that the MCU 700 uses the generated pulse error as a zero point.

When the hall sensor 600 transmits position information of the stator, the MCU 700 generates phase voltages of the BLDC motor 400 with the position information.

The Hall sensor 600 can obtain an output as shown in FIG. 2B when a current flows through a coil wound around the stator.

The three Hall sensors 600 built into the BLDC motor 400 provide digital signals obtained by measuring the rotor position within a 60 degree sector to the MCU 700.

As the BLDC motor 400 rotates, the current to the motor terminal is electrically switched (rectified) every 60 degrees, so the current space vector is always within the nearest 30 degrees in the orthogonal direction.

The shunt resistor 500 measures the amount of current generated while driving the BLDC motor 400 .

The MCU 700 receives the amount of current measured by the shunt resistor 500 and determines how much moment (force) the corresponding BLDC motor 400 currently has.

The MCU 700 is connected to the capacitor 240 of the power conversion module 200 and measures the voltage of the corresponding capacitor 240 to obtain a constant voltage from the SIC module 300 when the BLDC motor 400 is driven. Allow current to be applied to the BLDC motor 400.

In the process of converting AC power and supplying it from the condenser 240 to the BLDC motor 400, when a non-constant voltage current is supplied, damage to the SIC module 300 may occur, so that a constant voltage is supplied to the BLDC The MCU 700 needs to measure the voltage of the capacitor 240 so that it can be applied to the motor 400 .

Since the MCU 700 outputs a voltage of 5V and the SIC module 300 has a gate trigger voltage of 15V, a voltage of 15V or higher must be applied to perform 35mΩ switching according to the data sheet.

Therefore, the gate driver 900 formed between the MCU 700 and the SIC module 300 has a built-in boost circuit to convert the output voltage of the MCU 700 to the gate voltage of the SIC module 300. change the level

A high-speed photocoupler for communication is used as a gate signal control element of the SIC module 300, and the MCU 700 generates a gate control signal so that the SIC module 300 can be switched at high speed.

The BLDC motor 400 includes a permanent magnet as a rotor inside, and when the temperature of the permanent magnet rises above a critical value, the magnetic field weakens and the coil burns out.

Accordingly, the MCU 700 measures the temperature of the BLDC motor 400 in real time or periodically to monitor the BLDC motor 400 so that the temperature does not rise above a threshold value.

That is, when the temperature of the BLDC motor 400 rises above the reference value, the MCU 700 controls the BLDC motor 400 not to be driven so that the temperature of the BLDC motor 400 falls below the reference value.

As shown in Patent Registration Publication 10-2258793 (May 25, 2021), the drum 800 internally rotates the drive gear, driven gear, and drum gear of the BLDC motor 400 meshed together.

In particular, the drum 800 has a wire connected to open and close the theater stage fire screen on its outer circumferential surface, and as the BLDC motor 400 is driven, it rotates in one direction to wind the wire to open the theater stage fire screen, and in the opposite direction rotates to release the wire to close the stage fire screen of the performance hall.

In the above, the technical idea of the present invention has been described together with the accompanying drawings, but this is an illustrative example of a preferred embodiment of the present invention, but does not limit the present invention. In addition, it is obvious that various modifications and imitations can be made by anyone having ordinary knowledge in the technical field to which the present invention belongs without departing from the scope of the technical idea of the present invention.

100: commercial power supply
200: power conversion module
210: bridge diode
220: resistor
230: electromagnetic contactor
240: condenser
300: SIC module
400: BLDC motor
500: SHUNT RESISTOR
600: hall sensor
700: MCU
800: drum
900: gate driver

Claims (5)

In the inverter of the BLDC motor for driving the fire barrier separating the stage and the audience in the event of a fire,
Commercial power supply for inputting AC power;
a power conversion module for converting AC power supplied from the commercial power supply unit into DC power;
a SIC module that receives DC power supplied from the power conversion module and converts it into power required by the BLDC motor;
An MCU controlling speed and torque of the BLDC motor by switching a carrier frequency to a 114KHZ band through a pulse width modulation (PWM) variable voltage;
A plurality of Hall sensors that are formed inside the BLDC motor and sense the position information of the rotor as an element through which current flows when a magnetic field is received; including,
The MCU
In the process of measuring the signal generated when the BLDC motor rotates instead of the encoder, an encoding numerical error occurs due to distortion of the corresponding signal in the process of measuring the signal generated when the BLDC motor rotates, and the accumulated error is treated as zero point to eliminate the accumulated error. A low-noise inverter of BLDC motor for driving the fire screen of the stage equipment of the performance hall.
According to claim 1,
A gate driver formed between the MCU and the SIC module and converting the voltage level from the output voltage of the MCU to the gate voltage of the SIC module; BLDC for driving the fire screen of the theater stage device further comprising Low-noise inverter for motors.
delete According to claim 1,
The MCU
A low-noise inverter of a BLDC motor for driving a fire screen of a theater stage device, characterized in that by measuring the temperature of the BLDC motor in real time or periodically to monitor the BLDC motor so that the temperature does not rise above a threshold value.
According to claim 1,
The MCU
A low-noise inverter of a BLDC motor for driving a fire screen of a theater stage device, characterized in that it determines how much moment (force) the corresponding BLDC motor has by receiving the amount of current according to the driving of the BLDC motor measured by the shunt resistance .