Inverter applications on the escalator

    Current conventional escalator is still no-load rated speed operation, high energy consumption, mechanical wear, long service life and low defects. For example, 16 Jilin Trade Mall escalators, each electric power escalators 8kW, power 70kWh per day about escalators, running 11 hours a day, and always constant speed operation, in most cases, run at higher escalator 2/3 of the rated capacity or less, no-load each time the cumulative daily escalators for about 5 hours. If the escalator in the absence of the no-load shutdown or put on hold, will greatly reduce electricity consumption. If the escalator from the daily continuous operation mode was changed to constant run properly when riding constant speed, no ladder slow moving or stopped, will be able to achieve the purpose of saving. Reference to the large amounts of data, I feel this way can achieve.

    After research trials in escalator installation of electrical control circuit inverter, can be realized by a simple transformation of this function. Frequency control mode control escalator run, so that the escalator with a smooth start, energy-saving operation. No ladder, the escalator from the rated speed into low-speed operation, which saves energy, but also reduces the mechanical wear. When a passenger approached, escalator starts running at normal speed; passengers left, escalators deceleration becomes slow running or stopped, waiting for the next one passenger. If passengers continuously, escalators will continuously run at normal speed, until the last one to leave the escalator passengers.

    Now most of the production is no escalator speed control function, and escalators are made by three-phase asynchronous motor driven mechanical parts gearbox operation. According to the motor theory, AC motor speed formula is:

n = 60 × f / p (1 - s)

Formula: f is the frequency of the stator power; p the number of pole pairs; n is speed; s the slip.

(A) change the motor pole pairs p can change the motor speed, which is used in AC double-speed motor speed control method.

(Two) by adjusting the size of the stator winding voltage to change the purpose of the slip s to achieve speed control, which is used in AC variable speed motor speed control method.

(Three) the power to change the stator frequency f can achieve speed control purposes, but f can not exceed the maximum rated motor frequency, elevator as a constant torque load, speed and time in order to maintain maximum torque constant, according to the torque equation:

M = CmφIcosφ

The formula: Cm for the motor constant; I is the rotor current; φ of the motor air gap flux; cosφ the rotor power factor, φ must be kept constant. Also according to the voltage equation:

U = 4.44fWkφ

Where: U is the stator voltage; f is the stator voltage frequency; W is the stator winding turns; k constant for the motor, must be maintained U / f is constant, and according to principles of motor drive, the speed ratio of the ratio equal to the frequency equal to voltage ratio,

Equal to the power ratio.

Namely N0 / N1 = f0 / f1 = U0 / U1 = P0 / P1

Ie, the inverter must both transformer, frequency two functions, which is the fundamental frequency elevator control principle.Third, the economic analysis Change the existing variable speed constant escalator escalator, taking into account the motor without change, the original of the motor, after verification, the most effective way to save energy is to install the drive. By changing the power frequency inverter to achieve the purpose of speed. For example:Escalator motor for the two pairs of pole single speed motors, according to the formula

n = 60 × f / p (1 - s)

When the slip little change, n is essentially proportional to f. Escalator constant speed f = 50Hz, motor speed:

n = 60 × 50/2 = 1500, i.e. 1500 rpm.

Escalator slow line f = 20Hz, motor speed:

n = 60 × 20/2 = 600, 600 revolutions per minute.

When the motor is rated at 380V, frequency is 50Hz, through the inverter to change the frequency, the frequency of the original frequency of 40%, ie 20Hz when sent to the motor voltage becomes:

U1 = (380V × 20Hz) / 50Hz = 152V

According to the formula U0 / U1 = P0/P1 drawn P1 = 0.4P0

Thus the electric power consumed by the motor is 40% of the original power.

Based on the above projections, a 8kW electric motor, running 11 hours a day, electricity is 1 yuan per kWh, then it is a day of electricity:

1 × 11 × 8 × 0.8 = 70.4 million.

After installing the drive, if the daily Slow Running time 50% of the day, then slow-consuming daily tariff is:

1 × 5.5 × 8 × 0.4 × 0.8 = 14.08 million.

After installing the drive as a daily consumption: 70.4 / 2 +14.08 = 49.28 yuan.

After installing the drive as a daily saving: 70.4-49.28 = 21.12 yuan.

By measuring the actual saving energy meter around 20kWh per day.

Xi'an YuanQi Elevatorparts Company: Use high-quality elevator parts, for everyone's sa...

Xi'an YuanQi Elevatorparts Company: Use high-quality elevator parts, for everyone's sa...: According to data released by AQSIQ, China's annual increase in the number of elevators 300,000 or more. In many security risks, the...

Use high-quality elevator parts, for everyone's safety!

According to data released by AQSIQ, China's annual increase in the number of elevators 300,000 or more.

In many security risks, the current security threats on the domestic elevator use the most prominent is the "aging" crisis. According to statistics, China's elevator ownership has more than 1.63 million units, of which a considerable part of the 1990s, installation of an elevator, use the time up to ten years, and even some elevators used for over 20 years. However, due to the current state does not provide for mandatory retirement age elevator, leading to a large number of old elevator still sick to run, increasing the incidence of elevator accident.

"At present, Shanghai more than 15 years old accounted for a rough estimate of the old elevator lift 15% of the total, including each zone subway escalators, elevators old district of Van, some large shopping malls and other public elevator, this figure annually are incremented. these "overage elevator", if maintenance work has not kept up, there may be some security risks.

Elevator accidents, 80% of accidents happened in the maintenance aspect, which is the follow-up repair and maintenance is not in place, which is of special equipment testing, maintenance, updates, and other related procedures are not standardized. Maintenance units in order to save costs, parts procurement in the elevator will greatly lower prices, which led to a lot of substandard elevator parts into the market. Brought to the elevator market risks!

Elevator Association Expert Committee official said that China Elevator Maintenance is mainly based on "Management and maintenance of elevator use rules" maintenance units in accordance with the contract, the company commissioned by the property for 15 days once the elevator maintenance. But most repair and maintenance units are small, weak, poor treatment, difficult to cultivate and retain high-level skilled workers. Combined with a lot of elevator owners to implement "Maintenance subcontracting" third party in order to save costs, maintenance is likely to result not in place, risk increased. With this stage to improve the quality of people's lives, the increasingly high demand for travel, the elevator has become an irreplaceable tool. If the elevator can not guarantee the safety of people's lives, then how should we do it? So called Maintenance units and an elevator manufacturers, elevator parts used to strengthen the control. Lifts can be used to ensure that each high-quality elevator parts!

Elevator "old age", plus maintenance negligence, so that every day dealing with the elevator user misgivings. Who lives in an old district of Pudong, Shanghai Hu Kai described to reporters that he built in the district where earlier time, a problem often encountered in the elevator situation. "Although the property and also reflect over, but the maintenance is after all a temporary solution, but it can often fail to pass the annual, I also find it strange."

Xi'an YuanQi Elevatorparts Company: How does elevator inverter work ?

Xi'an YuanQi Elevatorparts Company: How does elevator inverter work ?: Now lift  elevator inverter  principle are used to control the frequency converter, the fault when the inverter will cause inconvenience ...

How does elevator inverter work ?

Now lift elevator inverter principle are used to control the frequency converter, the fault when the inverter will cause inconvenience to many people, if maintenance personnel can correctly understand the principle of elevator drive, then you have easy maintenance. Here by us Hui Bo Times Technology Co., Ltd. was telling you about this knowledge. VVVF Variable Voltage and Variable Frequency is the acronym meaning changing the voltage and frequency of change, that is, they say, VVVF. CVCF is Constant Voltage and Constant Frequency acronym, meaning constant voltage, constant frequency, that is, they say, constant voltage constant frequency. We use the power into AC power and DC power, DC power supply generally mostly through the transformer from the AC power source transformer, rectifier obtained. AC power using the power of the people accounted for 95% of the power used. Whether for home or for factories, single-phase and three-phase AC power supply, the voltage and frequency according national regulations have certain criteria, such as mainland China provides direct user single-phase AC power is 220V, three-phase AC wire voltage 380V, frequency of 50Hz, other countries may be in supply voltage and frequency of the voltage and frequency are different, if single-phase 100V/60Hz, three phase 200V/60Hz, etc., the standard voltage and frequency of the AC power supply called frequency alternating current.

Typically, the voltage and frequency fixed frequency alternating current is converted to a variable frequency AC voltage or a device called a "drive." In order to generate a variable voltage and frequency, the device is first necessary to convert AC power to DC (DC), this process is called rectification. The direct current (DC) is converted into alternating current (AC) of the device, its scientific term for the "inverter" (inverter). General Inverter is the DC power inverter is a certain fixed frequency and constant voltage power inverter. For the adjustable frequency inverter, voltage adjustable frequency inverter we called. Inverter output waveform is an analog sine wave, is mainly used in three-phase induction motor drive with, also known as inverter. Mainly used in the instrumentation for the detection devices require a higher variable frequency wave inverter, to sort out the waveform, you can output standard sine wave, called the variable frequency power supply. Frequency power inverter prices are generally 15 - 20 times. Since the inverter device generates a voltage or frequency changes in the primary device called "inverter", so the product itself is named "inverter", namely: inverter. Inverter can also be used in home appliances products. Use the inverter home appliances products, not only motor (such as air conditioning, etc.), as well as fluorescent lamps and other products. Inverter for motor control, either change the voltage, but also can change the frequency. But are used primarily for regulating fluorescent lamp inverter power supply frequency. Used car battery (DC) to produce alternating current devices "inverter" name for sale. The working principle of the inverter has been widely used in various fields. Such as computer power supply, in the application, the drive for inhibiting reverse voltage, frequency fluctuations and power of instantaneous power.

We repair a lot of the elevator inverter schematic inverter for elevator and found a lot of trouble because of their work environment through high temperature components likely caused by aging, elevator inverter installed in the building's topmost control room, often in the summer by sun exposure, coupled with the drive itself and the braking resistor heating, the electrical room temperature is very high, the working environment temperature will shorten the life of electronic components! Drive more obvious in this regard, the elevator electrical room ventilation problems in the design in addition to also pay attention to insulation, such as walls with hollow bricks, chamber top multi-layer design, if accompanied by an air conditioner, the drive's lifespan considerably longer !

Xi'an YuanQi Elevatorparts Company: The use of elevator inverter

Xi'an YuanQi Elevatorparts Company: The use of elevator inverter:     VVVF elevator inverter lift electronic control system includes the main controller, inverter and other hosts. MicroMaster440 series inv...

The use of elevator inverter

    VVVF elevator inverter lift electronic control system includes the main controller, inverter and other hosts. MicroMaster440 series inverter is developed by Siemens Multifunctional inverter. It's rated power ranges from 0.12Kw to 75Kw (constant torque), using a modular design, compact structure, having a plurality of freely defined input and output points, to meet a variety of customer requirements. The inverters are microprocessor controlled and uses advanced technology with modern insulated gate bipolar transistor (IGBT) as the power output devices. Therefore, they have a high reliability and functional diversity. A pulse width modulation switching frequency is optional, which can reduce the operating noise of the motor. Full and complete protection for the inverter and the motor provides a good protection.

Control System Components

    Electric control system uses a table 15kw motor, an inverter 15kw MicroMaster440 units as the main driver. Inverter braking unit and braking resistor feedback when releasing the brake run mechanical energy. System is simple and reliable, more traditional control method saves installation space, and improve reliability. Smooth motor starting current impact is small. Mechanical shock is also greatly reduced, increased operating life. Inverter control via terminals through digital input terminals (DIN) ON/OFF1 command and given a fixed frequency reference. Through three relay output signals to the feedback current inverter operation status, received by the encoder template rotary encoder signals. Inverter using closed-loop vector control.

Operating principle and functions

    Elevator inverters are used in applications where higher-end transmission applications must use closed-loop vector control to achieve good control effect. Vector control is a theory first proposed by Siemens and the practical realization of the project first phase asynchronous motor control, has reached the level of DC motor control. It simulates the DC motor control torque of the motor current is divided into two directions, respectively, and the excitation control can be used for high-precision speed control, torque control. In order to avoid starting to slip, and to overcome the startup guide shoes and static friction between the rails is a good start to achieve comfort, you need to start the process, open the front brake that is applied to a very small additional speed setpoint to inverter, the brake open the motor is in apparent motion non-moving state to strictly follow the speed given curve, to ensure comfort.

Xi'an YuanQi Elevatorparts Company: elevator inverter commissioning

Xi'an YuanQi Elevatorparts Company: elevator inverter commissioning: elevator inverter commissioning 1 Set the motor power, very few, considering the elevator to the operating current of the inverter. (2) S...

elevator inverter commissioning

elevator inverter commissioning
1 Set the motor power, very few, considering the elevator to the operating current of the inverter.
(2) Set the maximum output frequency of the inverter elevator, baseband, set the torque characteristics. Universal elevator inverter are available in many VPf curve for users to choose, users should be used according to the nature of the load curve select the appropriate VPf. If the fan and pump load, the torque converter to the elevator run code set to become operational characteristics of torque and torque reduction. In order to improve low-speed elevator inverter startup performance, so that the motor output torque can meet the production requirements of the load starts, to adjust the starting torque. In Thyssen Elevator parts of induction motor speed control system, the torque control is more complex. In the low frequency range, since the resistance, the leakage resistance effect can not be ignored, if VPf remain constant, the flux will decrease, thereby reducing the output torque of the motor. Therefore, the voltage at low frequencies to be appropriately compensated for to improve torque. Lift the drive by the general user manual to set the compensation. 3 Set the elevator inverter comes with keyboard operation mode, press the Run button, stop button, observe whether the motor can normally start, stop.
4 familiar with the drive is running a protection code fails to observe the thermal protection relay factory value, observe overload protection settings can be modified if necessary. The use of personnel elevator inverter can drive to the operating instructions for the inverter to set the electronic thermal relay function. When the inverter output current exceeds its allowable current, the inverter overcurrent protection will shut off the inverter output. Therefore, the inverter electronic thermal relay does not exceed the maximum threshold for the maximum allowable output current of the inverter.