electric energy meter Energy-saving technology

AC contactor AC contactor is widely used in low voltage circuits, is a safe, easy to control, CNC Electric‍ volume and a wide range of industrial necessities. Now commonly used in the rated current 63A and above large, medium-capacity AC contactor should more than million Taiwan dollars electric energy meter, its operating system at the time of retention of electromagnetic active power consumed between 10W ~ 100W; reactive power consumed in the Dole circuit breakers‍ spent tens to hundreds of spent between Seoul. The active power consumption distribution is roughly: 65% to 75% of the core, the short-circuit ring 25% to 30%, the coil 3% to 5%. For such a being in the industrialization and urbanization of exchanges and contacts with large country, and the energy needs of the growing tension, saving power resources has become imperative.

Such as the AC contactor solenoid operating system with an appropriate energy-saving technology to its operating system, the original design of electromagnetic ac to dc retention retention, core and short ring can save most of the loss in power, to obtain a high energy-saving efficiency (typically active saving rate> 90%). Moreover, through the Switchgear & Substation‍ transformation can reduce or eliminate noise, reduce the temperature rise of the coil and extend the service life of the contactor.

Voltage stabilizer Energy-saving products Categories

AC contactor mainly depends on its energy-saving program works and the corresponding structure processes. Fat suction within the electromagnetic AC contactor by Circuit Breakers‍ constant component F0 and F ~ alternating component composition. Among them:

Constant component: F0 = Fatm / 2 (Fatm = 107 B2 MS / 8π)

Alternating component: F ~ = F0 cos 2ωt.

At work, due to the armature reaction force always been the role of the spring, the contact springs Fr reaction force, the electromagnetic suction averages Fat> Fr; when Fat <Fr armature at the beginning of the release voltage stabilizer‍, Fat> Fr armature also was attracted state, so Again and again, the armature vibration and noise. At this point in the alternating magnetic core produced by hysteresis loss and eddy current loss will cause the core heat (superposition of silicon can play a role in reducing the eddy current losses). To reduce operating noise is usually electri calmete‍ open in the small capacity of the electromagnetic system yoke ends embedded in a small groove corresponding short-circuit ring, and its role is to be divided into two parts by the core flux, that does not pass through the magnetic flux Φ1 and short-circuit loop the magnetic flux Φ2 through the short-circuit loop, and Φ2 lag Φ1, suction is always greater than the synthesis reaction, thereby reducing the vibration and noise, but also increases the copper loss accordingly.

AC contactor power mainly by the retention power and pull the power of two parts, although larger coil pull starter instant power, but time is very short (tens of ms); working time has been in the retention hold (at this energy loss is mainly concentrated in the state of retention on iron loss). That is why if they can reduce the AC contactor work retention can save energy consumption, CNC Electric‍ according to this principle, the current energy contacts broadly categorized as follows.

Voltage stabilizer Coil-saving and Saver

Saver is divided into: capacitive, transformer, duty cycle (change) type. AC contactor Saver corresponding supporting the use of the contactor in the DC state retention operation, air circuit breaker‍ so to save energy. Saver AC contactor solenoid due to electromagnetic energy and the internal device Saver limitations generally applicable to the rated current of 60 ~ 600A AC contactor, lower than 60A AC contactor because the stored electromagnetic solenoid can run in DC maintain its pull; electromagnetic greater than 600A AC contactor can be easily generated so Saver damage internal components voltage stabilizer.

Contactor coil AC passed, it will produce a corresponding inductance, inductive influence of the size of the size of the current in the coil, AC solenoid coil inductance, the core is not closed when the inductance is small, a large current through , which is caused by the coil in the suction power of the largest timely reason. Circuit breaker‍ When the AC contactor pull into the retention time, due to long-term work in the state coupled with the coil power consumption, temperature rise. AC contactor usually work long hours can produce 50 ℃ ~ 60 ℃ degree heat, the summer plus 30 ℃ ~ 40 ℃ ambient temperature of the coil temperature rise faster. Coil long period of high temperature operation, will accelerate the aging and even burned, AC contactor life will be shortened.

According to AC contactor coil power consumption characteristics of fast rise, by reducing the power consumption and temperature to save energy. According to the internal structure, saving coil is divided into: double winding type, current limiting resistor, double winding self-conversion conversion type and location. Works will use energy-saving coil is usually on its pulsating DC coil retention program run: pull winding generally larger diameter, fewer turns, and thus lower impedance, resulting pull current large; retention winding general smaller diameter, number of turns, current transformer‍ the impedance of large, small and therefore holding current. Corresponding increase rectifiers and varistors and film capacitors, the AC contactor is energized to work in DC state, large starting current to ensure a reliable pull-electromagnetic systems, smaller holding current to reduce the retention power, thereby reducing the electrical losses and electromagnetic coil temperature of the system.

Energy-saving AC contactor

According to AC contactor structure, increasing as Power Saver, saving coil, mechanical locking device, electromagnetic system to the remanence (permanent magnet) retention type, etc., can play the energy saving effect. After contact with the tradition of saving energy, such as shown in Table 2.

Traditional CJ10, CJ12, CJ20 AC contactor, for example, for energy saving before and after comparison of the data, reflecting the energy saving effect.‍

In CJ20 / 400A / 3 year energy savings calculation: saving work properly before the contactor holding power for 180W, priced according to the average electricity tariff by 1 yuan / Kwh meter, working hours 12h / day:

Total power consumption before saving: 0.18Kw × 12h × 365 = 788 Kwh

After saving the total power consumption: 0.006Kw × 12h × 365 = 26 Kwh

Saving (annual electricity): 788Kwh - 26Kwh = 762Kwh

Cost-saving: 762Kwh × 1 元 / Kwh = 762 元

At present, energy-saving AC contactor has a certain market, but not enough popular, traditional exchanges and contacts currently in use on the dominant user. The main reason is the energy-saving type contactors expensive, the user can not accept the one-time investment, to be national policy to electric meter‍ increase efforts on the promotion of energy-saving contacts, promote the wide application of energy-efficient contactors....

electric energy meter Thyristor inverter circuit

Thyristor inverter circuit to convert the direct current into alternating current, which corresponds to a reverse process of the rectifier, is defined as an inverter. For example: power transformers‍ The thyristor electric locomotives electric energy meter, when the DC motor as a generator downhill braking operation, the locomotive of potential energy into electrical energy, trans go to the AC grid. Another example is the operation of a DC motor, brake to make it quickly, but also allows the motor as a generator to run the motor kinetic energy into electrical energy, anti-delivered to the grid. The converter operates in inverter state, if the converter is connected to the AC side of the AC power to DC to AC inverter with a Circuit breaker‍ frequency counter to the grid to go, called active inverter.

Voltage stabilizer AC inverter circuit Rationale

The DC circuit is called reverse into AC inverter circuit. In certain cases, the same set mcb circuit breaker‍ of thyristor rectifier circuit can make, but for the inverter.

The converter operates in inverter state voltage stabilizer‍, if the converter is connected to the AC side of the AC power to DC to AC inverter with a frequency counter to the grid to go, called active inverter. If the change is not the AC side current grid connection, but directly to the load, which converts DC to a certain frequency or adjustable frequency alternating current supplied to the load, then called passive inverter. AC frequency control is the use of CNC Electric‍ this principle. Except for the DC reversible active inverter speed control system, but also for AC induction motor rotor Rao line cascade control and other aspects of HVDC.

2 relative concept

Convert alternating current to direct current approach is rectified; and convert DC to AC inverter method.

Rectification, full-wave rectifying circuit is the use of one-way conduction of the diode characteristics, with four diodes connected into a bridge rectifier circuit voltage stabilizer‍, the input terminal is an AC current, the waveform is a sine wave, the direction of the alternating current, and an output terminal waveform current becomes the same direction, AC Contactors‍ and then through a filter circuit to obtain a DC waveform after filtered.

electric energy meter Inverter Classification

Source inverter also has passive inverter. For example, the DC voltage, through a simple, single-phase thyristor bridge type H, H is the output of the cross on each of the electric meter‍ four H's vertical thyristor, electric energy meter, at 34, 14 and 23 were opened to give a positive negative separated the output voltage and current.

The pulse width modulation inverter technology

Basic square wave inverter circuit is simple, but the output voltage waveform harmonic content is too large, but also both the THD (current harmonic distortion) is too large; the phase shift of multiple superimposed small harmonic content inverter output voltage waveform, That THD is small, but the circuit is more complex. The PWM pulse width modulation inverter, both the computer's circuitry, and the output voltage waveform, which has been widely used.

The so-called PWM technology (Pulse Width Modulation, PWM), is made of a reference wave (usually a sine wave, sometimes with a trapezoidal wave or injected zero sequence harmonic Electric transformer‍ sine wave or square wave, etc.) for the modulation wave (electric energy meter), and to N times the frequency of the modulation wave of the triangular wave (sawtooth wave is also sometimes used) of the carrier (Carrier Wave) waveform comparison, the modulation wave is greater than the carrier portion to generate a set of equal amplitude and a width proportional to the modulated waves equivalent rectangular pulse sequence is used to modulate the wave instead of using analog switch, and through the inverter power switch on / off control, the DC power into AC power, this technique is called pulse control inverter technology. Because triangular carrier wave (or sawtooth) vertical section is a linearly varying degrees, so this technique is called pulse control inverter technology. Since the triangular carrier wave (or sawtooth) is vertical width is linear, so that this modulation is linear, when the modulation wave is a sine wave, a rectangular pulse width of the output pulse train changes sinusoidally, this modulation Air circuit breaker‍ technique typically also known as the sinusoidal pulse width modulation (Sinusoida PWM) technology.

Voltage stabilizer Inverter FAQ

u outside interference

The inverter may be due to a number of occasions in the strong electromagnetic interference, such as motors, power inverter, a strong magnetic field in the vicinity.

Far away from the device similar to circuit breakers‍ the above.

u inverter does not respond

1. Battery and the inverter is not connected, reconnect.

2. Battery pole reversed, the fuse is blown. Replace the fuse.

u output voltage is low

1. Overload, load current exceeds the nominal current, turn off some of the load restart.

2. Input voltage is too low. Ensure input Cncelegroup‍ voltage is within the nominal voltage range.  

electric energy meter Inverter include:

Dedicated power inverter

Communications for power inverter   

Frequency inverter powered

Industrial sine wave inverter

Square wave inverter

The role and characteristics of medical Inverter

Due to a variety of different types of medical equipment supply needs, use the most is the centralized power structure. I.e., by a power converter to produce the desired concentration of various voltage air circuit breaker‍ levels of the output voltage. Due to its low cost, high efficiency, adjustable output voltage electric energy meter, low output noise, fast dynamic response and other type of equipment is very suitable for medical use, is a medical device is currently the most used type of a power supply. Medical equipment supply program to determine the need to consider the following questions.

Security and isolation is a major difference between the ordinary commercial power and medical supply. Typically, in addition to some experimental analysis class equipment, medical equipment mostly installed near the bed or the operating table, and the operator's distance from the more recent, the shell will often be Circuit Breakers  ‍touched. There are a variety of medical equipment inside the strong, weak parts, if the strength of electrical isolation between the insulated shell material or have a problem, it will be very dangerous. General medical equipment safety testing power supplies must be UL60601-1, C-UL, EN60601-1 safety certification. Inputs and outputs must be more than 4,000V isolation voltage, and low leakage current requirements to meet safety creepage distance requirements. And part of the need for a strong electric double insulation, especially some of them might be more in contact with the enclosure designed to enhance insulation.

Electromagnetic compatibility and immunity to electromagnetic interference

Select the type of equipment to be medical or build a good power supply system must focus on improving the supply of electromagnetic compatibility and electromagnetic interference. CNC Electric‍ Mainly from the following aspects to consider: design. PCB design and layout, in general will contain some of the high frequency power signal, any traces on the PCB can be functioned as an antenna, the length and width of the printed lines will affect the resistance and inductance, thus affecting the frequency respond in a timely manner will be coupled to the RF signal and cause problems through the circuit traces DC signal from adjacent tracks. Medical power supply must be selected so that the big brands, has a strong R & D strength of the company's products, which in the design and production processes can ensure good quality.

Shield

In order to suppress the switching power supply generated by radiation, eliminate the influence of electromagnetic interference from other electronic devices in the medical equipment electric energy meter‍, the best way is to supply the magnetic shield, the shield and then the entire cabinet or medical Power Transformer‍ devices to a single entity, this is a more effective approach.