KR101214264B1

KR101214264B1 - Ac moter pump

Info

Publication number: KR101214264B1
Application number: KR1020100079971A
Authority: KR
Inventors: 배성호; 김진선
Original assignee: 김진선; 배성호
Priority date: 2010-08-18
Filing date: 2010-08-18
Publication date: 2012-12-20
Also published as: KR20120017339A

Abstract

The present invention improves the pressure switch installed in the pressure tank of the conventional single-phase AC motor pump 10 to quantitatively extract the height of the pressure state in the pump 10 to control the phase of the AC voltage in the pumping operation proportionally or pulse Single-phase AC motor pump that can control the strength of operation (control of the speed of AC single-phase induction motor) flexibly by controlling width switching, minimizing power consumption and allowing smooth operation. It relates to the control apparatus of (10).
The control device of the single-phase AC motor pump 10 has a pressure tank, and in the single-phase AC motor pump 10 having a pressure switch coupling part 12 in the pressure tank,
It is provided with a pressure sensor unit 20 having a fastening portion 22 corresponding to the pressure switch coupling portion 12 to replace the pressure sensor unit 20 in place of the pressure opening and closing switch,
The pressure sensor unit 20 has a housing and a pressure sensor 26 inside the housing, and proportionally outputs the driving motor 14 based on an analog signal of increasing or decreasing type by the pressure sensor 26. Configure a control board 24 having a control circuit for controlling,
The pressure sensor 26 is formed in a long shape so as to be exposed to the pressure tank through the fastening part 22 of the pressure sensor unit 20 and to be installed tightly so as not to be flooded into the pressure sensor 26 and the circuit board. It is characterized in that the installation of the pressure transmission unit.

Description

Control device of single phase AC motor pump {AC MOTER PUMP}

The present invention improves the pressure switch installed in the pressure tank of the conventional single-phase AC motor pump to quantitatively extract the height of the pressure in the pump to control the phase of the AC voltage in the pumping operation or operate by controlling the pulse width switching. The present invention relates to a control device for a single-phase AC motor pump that can flexibly control the strength of the AC motor (speed control of an AC single-phase induction motor) to minimize power consumption and to allow smooth operation. .

In general, single-phase AC motor pumps, which are installed and operated in homes, rural areas, and some industrial uses, have a simple structure and low-cost mechanical pressure switch.

In this conventional method, since only two outputs of ON / OFF are possible, the driving motor also repeats 100% ON operation or 0% OFF operation, so smooth operation is not possible. In other words, when the pressure is low, when the switch is turned on and the pump is operated, a starting current is applied to operate the motor to a normal range quickly.When the pressure is high, the operation is stopped by abruptly shutting off the power by cutting off the power supply. As a result, power consumption increases, as well as a water hammer phenomenon occurs due to a sudden stop of the driving motor, and due to the shock, vibration or shock is given to the structure including the pipe, thereby deteriorating durability. For example, when a small amount of water is pumped, the switch is frequently turned on and off because the pressure change is small. At this time, the motor consumes a starting current to produce a normal speed every time despite the frequent ON / OFF operation, so the power consumption increases. In addition, even if the pump is stopped due to the driving motor applying the starting current, if the pump is suddenly stopped, the water pressure that is pumped causes a water hammer phenomenon that impacts the valve, the pipeline, and the pump, resulting in a decrease in the strength of the structure or the fastening between structures. Loose phenomenon such as sickle, bolt, etc. occurs, and the durability of the pump is reduced. In particular, if the driving motor frequently starts / stops repeatedly, pulsation may occur severely, resulting in a decrease in durability of the pump. This not only increases maintenance costs, such as after-sales costs, but also causes noise problems due to frequent pump operation.

In order to solve this problem, some pumps employing a motor capable of inverter control and vector control are operated. However, this type of motor pump has a disadvantage of requiring an expensive initial purchase cost and requiring considerable knowledge for maintenance. .

The present invention has been made to solve the above-mentioned conventional problems, the object of the present invention, the control method by the on / off simple mechanical pressure switch installed in the pressure tank of the conventional single-phase AC motor pump, pressure sensor By changing to analog control method such as increase / decrease which is provided by the motor, single-phase AC motor drive is proportionally controlled by phase or pulse width switching instead of simple on / off control to minimize power consumption and smoothly operate the pump. It is to provide a single-phase AC motor pump control device to maintain a stable mechanical durability for a long time, and to enable quiet operation by minimizing noise.

According to an aspect of the present invention,

In the single-phase AC motor pump having a pressure tank, and having a pressure switch coupling for mounting a pressure on / off switch in the pressure tank,

A pressure sensor unit having a fastening part corresponding to the pressure switch coupling part may be replaced with a pressure sensor unit instead of the pressure switching switch.

The pressure sensor unit has a housing, a pressure sensor inside the housing, and a circuit board comprising a control unit for controlling the output of the driving motor in proportion to the output signal based on an analog signal of an increase or decrease by the pressure sensor and a circuit supporting the same. Install, configure,

The pressure sensor is formed in a long form in the lower part of the pressure sensor is exposed to the pressure tank through the fastening portion of the pressure sensor unit is characterized in that it is installed and configured to be installed tightly so that it does not become flooded into the pressure sensor and the circuit board.

In addition, the control unit according to the present invention compares the signal value sensed by the pressure sensor according to the set pressure range value input, when the pressure sensing value is less than the set value to operate the drive motor by turning on the switch,

If it is greater than or equal to the set value, cut off the switch to turn off the drive motor.

The set value is the upper pressure limit that determines when the driving motor should be turned off because the water pressure to be maintained by the pump is satisfied, and the water pressure is lowered below the boundary point where the water pressure drops due to the cause of water supply. Configure the lower pressure limit when the motor is running,

When the water pressure is low and the water pressure drops below the pressure lower limit or lower, the drive motor operates to turn on the drive motor to the upper limit or higher and to control the supply of current so as to approach the upper limit, so as to have a smooth hydraulic pressure change. It features.

In addition, if the water pressure is equal to or higher than the upper limit of the set range, the drive motor is kept off and the user opens the valve to supply water. It is characterized in that the measured and increased to increase or decrease the current supplied to the drive motor in proportion to the displacement value.

The control device of the single-phase AC motor pump of the present invention is economical because it can be used as it is without changing the electrical wiring without changing the structure or wiring of the conventional pump, and can be installed and operated quickly and easily at the replacement level of accessories. .

In addition, through the sensing by the pressure sensor and electronic control through it, soft control such as smooth start and slow stop operation, not sudden start and stop, is possible, resulting in improvement of durability, noise reduction and safety improvement. This minimizes the occurrence of failures due to this effect, and reduces the maintenance costs, as well as the economic life of the product life is long.

1 is a structural diagram of a control device of a single-phase AC motor pump according to the present invention.
Figure 2a, 2b is an embodiment of a control device of a single-phase AC motor pump according to the present invention.
3 is a basic circuit diagram of AC phase control of a single phase AC motor pump according to the present invention;
4 is an AC PWM basic circuit diagram of a single-phase AC motor pump according to the present invention.
5 is a phase control block diagram of a single phase AC motor pump according to the present invention;
Figure 6 is a PCM control block diagram of a single phase AC motor pump according to the present invention.
7 is a phase control and PCM control characteristic diagram of the single-phase AC motor pump according to the present invention.
8 is a characteristic diagram of the starting speed of the single-phase AC motor pump according to the present invention.
9 is a conceptual diagram of the soft start and soft stop of the single-phase AC motor pump according to the present invention.
10 is a graph comparing the soft-start characteristics of the single-phase AC motor pump and the starting current characteristics of the general single-phase AC motor pump according to the present invention.
11 is a flowchart of a control device for a single-phase AC motor pump according to the present invention.

The single-phase AC motor pump 10 of the present invention includes a pressure tank as shown in FIG. 1, and has a pressure switch coupling part 12 for mounting a pressure on / off switch in the pressure tank.

The pressure switch coupling portion 12 is provided with a pressure sensor unit 20 having a fastening portion 22 fastened thereto. This is to minimize the cost and to facilitate the replacement operation by simply replacing by using the pressure sensor unit 20 instead of the ON / OFF controlled pressure switch that was used in the conventional motor pump 10.

The pressure sensor unit 20 has a housing and a pressure sensor 26 inside the housing, and proportionally outputs the driving motor 14 based on an analog signal of increasing or decreasing type by the pressure sensor 26. A control board 24 having a control circuit for controlling is configured.

In addition, if necessary, the power supply unit and the control board 24 may be installed as shown in FIG. 2B in a position for accommodating the starting capacitor and the power lead wire, and the pressure sensor 26 may be separately installed in the pressure switching switch seat. At this time, the pressure sensor 26 and the control unit are connected by a cable (power line, signal line).

The pressure sensor 26 is formed in a long shape so that the pressure sensor 26 is exposed to the pressure tank through the fastening part 22 of the pressure sensor unit 20 and is not flooded into the pressure sensor 26 and the control board 24. Install and configure the pressure transmitter which is installed in a watertight manner.

The control board 24 includes a power supply circuit for supplying electricity, a microprocessor 201, a phase detection circuit 204, and a motor driver 205.

The pressure sensor 26 receives the pressure applied to the pressure tank through the pressure transmitter and transmits an analog signal to the microprocessor 201. The microprocessor 201 receives the signal and compares it with the set pressure value to determine the proportional control (duty control or pulse control) based on phase as shown in FIGS. 3 and 5 or the AC switching control (PWM as shown in FIGS. 4 and 6). pulse width modulation) to control the output of the motor driver 205. In addition, it is preferable that the pressure sensor 26 is a popular type, and the pressure recognition range may be a type capable of sensing the comprehensive range of a conventional mechanical pressure switch on the market. The output signal is connected to the ADC input terminal of the microprocessor 201 through proper amplification process, S / W, and H / W filtering. The detection period of the signal is preferably set to (sampling time) 200 ms (five times a second).

In addition, the motor driving unit 205 uses a thyristor (triac, SCR, etc.) device as shown in FIG. 3, or a solid state such as a power transistor or a fidld-dffect transistor (FET) as shown in FIG. 4. desirable. Since the motor driving unit 205 implements soft start and soft stop through proportional control as shown in FIGS. 8 to 10, the motor pump 10, which is a control target, reduces noise and enhances durability.

In the control method of the motor driver 205, the phase proportional control circuit is separated from the control port of the microprocessor 201 by a photo triac as shown in FIG. Phase proportional control is performed by controlling the gate of evil (onion). The SCR or triac used must be rated above the rated components. Snubbers are added to the peripheral circuits.

In addition, as shown in FIG. 4, the AC pulse width switching control circuit insulates the TR or FET, which is a power control element, and the microprocessor 201 using a port coupler, and the switching frequency is about 15KHz to minimize annoyance to human ears during operation.

The microprocessor 201 prepares to perform the freeze / stuck prevention function by writing a type in which an E2PROM is built in and updating the past elapsed operating time by an hour unit when it is stopped. This time is cleared when operation starts.

When the power is out for a long time or the power of the motor pump 10 is cut off, the elapsed time at this time is not updated.

The control board 24 of the present invention constitutes a protection circuit. That is, a magnetic holding device (interlock) is provided in the control board 24 to stop the operation of the motor 14 from damage or abnormal operation of the microprocessor 201 to protect the circuit.

In addition, the pressure sensor 26 also monitors the microprocessor 201 continuously and determines that the sensed signal value is out of the effective upper limit value / lower limit value or does not match the minimum / maximum pressure change over time. The motor 14 is stopped and protected.

In addition, even during normal operation, if there is no change in pressure for a certain time after the start of the operation of the motor 14, it is determined that the idle, sensor failure or impeller is stuck by foreign matters and cannot rotate, and the motor 14 is stopped and protected.

In constructing such a protection circuit, it is preferable to use a commercially available earth leakage circuit breaker if installed and mixed in the power inlet of the front end of the power supply of the motor pump 10 to enhance safety. As a condition for installing the earth leakage breaker, the motor pump 10 may be spaced apart from each other to prevent damage due to flooding.

11 is a flowchart of a control device of the single-phase AC motor pump 10 according to the present invention. As shown in FIG. 11, a pressure upper / lower limit value for setting an on / off operating range of the single-phase AC motor 14 or the motor 14 is shown. When the pressure change value according to the operation of the time or the number of times is counted and the pressure measurement value does not change or the pressure change is slight, the machine stops in a state without difficulty to prevent mechanical failure or damage and Initialize the initial variable values, such as the limit time to inform the administrator, and then start the operation process.

When the operation process starts, first, the pressure value of the pressure sensor 26 is read and compared with the pressure lower limit value, and when the pressure is lower than the lower pressure limit value, the motor 14 is operated to operate the pump 10. At this time, if the pressure value is larger than the lower limit value, it is determined that the cause of operation of the pump 10 does not occur and returns to the start of the operation process, and the operation waiting time is accumulated in the process. When the standby state continues as the pump 10 is not operated and continues to be returned, the operation wait time is accumulated, and the motor 14 is forcibly driven when the set standby time is exceeded. When the pressure of the pump 10 is maintained for a long time, various impurities contained in the water in the conduit may stick to a place such as a pumping fan or a shaft and become solidified, causing malfunction. If the) does not operate, it counts and operates once when the set time arrives so that impurities do not settle. When the operation standby time exceeds the set time and the motor 14 is operated, only a short time is operated because the pressure is maintained.

On the other hand, when the pressure measured value falls below the lower limit, the motor 14 is operated and the pressure by the pressure sensor 26 is repeatedly measured and compared with the upper limit. As a result, when a value more than the upper limit value is measured, the motor 14 is turned off and returned to the starting sequence of the initial operation process.

If the pressure measurement value is kept above the lower limit value, it is determined whether the pressure displacement value exceeds the set pressure displacement value and whether the pressure displacement is zero (zero), and the control is performed accordingly.

When the measured value exceeds the pressure displacement value, the measured value of the pressure sensor 26 is returned in the order of reading, and when the pressure displacement value does not exceed the set input displacement value, the time is counted again to accumulate the accumulated time. If it is determined that the set time has been exceeded and it is not exceeded, the pressure sensor 26 is returned in the order of reading the measured value again, and if it is exceeded, emergency operation is performed. That is, it determines that the failure is sounding an alarm or lighting an emergency light and at the same time operating a breaker to cut off the power to stop the motor 14.

On the other hand, when the pressure measurement value is the same as the previously measured pressure value, that is, when there is no change in the pressure displacement value (zero value), the cumulative amount (time or number of times) is counted. If it is determined that the set cumulative amount has been exceeded and it is not exceeded, the measured value of the pressure sensor 26 is returned in the order of reading, and if it is exceeded, emergency operation is performed. That is, the motor 14 may overheat due to a failure in reading the pressure displacement due to a failure of the sensor. Thus, the alarm is activated and the breaker is activated to cut off the power supplied to the motor 14 to prevent an accident. .

In this order, the driving motor 14 operates, and when the motor 14 is stopped or operated, the smooth operation is performed by the soft operation circuit rather than suddenly starting and suddenly braking.

10-pump 12-pressure switch coupling
14-Motor 20-Pressure Sensor Unit
22-Fastening Part 24-Control Board
26-pressure sensor

Claims

In the single-phase AC motor pump 10 having the pressure switch coupling portion 12,
A housing,
Pressure sensor 26 for sensing the pressure of the pump in the housing,
A control board 24 having a control circuit for proportionally controlling the output of the motor 14 based on an analog signal of increasing or decreasing form by the pressure sensor 26;
A fastening part 22 corresponding to the pressure switch coupling part 12,
The pressure transmitting part 23 communicates with the pressure sensor 26 in a long form inside the fastening part 22 and transmits the water pressure of the pressure tank to the pressure sensor 26.
Composed of a pressure sensor unit 20 made of
Control device for a single-phase AC motor pump characterized in that the fastening portion 22 is fastened to the pressure switch coupling portion (12).

The method of claim 1, wherein the control circuit compares the signal value sensed by the pressure sensor 26 in accordance with the input set pressure range value
When the hydraulic pressure sensing value is lower than the set lower limit value, the motor 14 is operated by turning on a switch.
If it is greater than or equal to the set upper limit value, the motor 14 is turned off by blocking the switch.
When operating the motor 14 to raise the water pressure dropped below the set lower limit value to the set upper limit value, the water pressure displacement with time is measured at the water pressure in the off state of the motor 14 and the motor is proportional to the displacement value. A control device for a single-phase AC motor pump, characterized in that the increase / decrease control of the current supplied to (14) is performed.

delete

The method of claim 1, wherein the control board 24 is
The pressure sensor 26 measures the pressure applied to the pressure tank and transmits an analog signal to the microprocessor 201,
The microprocessor 201 receives the signal and compares it with a set pressure value, and determines the phase by using a phase control based on phase (duty control or pulse control) or AC switching control (PWM (pulse width modulation) pulse width modulation). A control device for a single-phase AC motor pump, characterized in that for controlling the output of (205).

The method of claim 2, wherein the control circuit
When the motor 14 is stopped, the past operation elapsed time is updated at a predetermined time period,
If the motor (14) does not drive even after the operation signal of the motor (14) is sent, the control device for a single-phase AC motor pump characterized in that it is determined that the failure due to freezing or seizure in the pipeline.