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Introduction to variable frequency power supply:

   ◇AC POWER ANDOURCE is a precision power source that transforms the mains power into the required voltage and frequency through a power conversion circuit. Due to the inconsistent power grid indicators of various countries in the world, the production of export products needs to simulate the power grid conditions of different countries. Test various export electrical products. In the past, a generator was used for secondary frequency conversion, but the power consumption was large, the noise was large, and the stability was poor. The variable frequency power supply can provide the standard grid voltage and frequency of all countries in the world. The output voltage and frequency are stepless digitally adjustable, which is suitable for voltage and frequency aging testing of exported electrical products. The variable frequency power supply can also be used as the power supply for imported 60HZ equipment.

   Features of variable frequency power supply:

◇ The variable frequency power supply adopts the sine pulse width modulation PWAND design and is promoted by the original imported Mitsubishi 1GBT. The response time is fast, for 100% load removal/loading, the voltage stabilization response time is within 2ANDAND. The waveform is pure, the frequency is high and stable, and there is no interference magnetic wave (EANDI, EANDC). The variable frequency power supply is not only the best power supply for R&D, laboratories, and measurement rooms, but also the standard power supply for EAND/EANDC/safety testing.

◇ The variable frequency power supply has the characteristics of strong load adaptability, high efficiency, good stability, good output waveform quality, easy operation, small size and light weight. For different types of power sources around the world, users can not only simulate the voltage and frequency (40 ~ 70Hz) around the world for test applications; among them, the special intermediate frequency power supply according to the national military standard can also support 400Hz, 1000HZ frequency of national defense military detection, avionics And navigation, communication and other application equipment.

   Variable frequency power supply purchasing principles and special customization

(1) When purchasing a variable frequency power supply, it is best to understand the nature of the load you will use. There are five types of load that you can see: 1. Resistive load, 2. Inductive load 3. Capacitive load: 4. Rectified load; 5. Hybrid load; 6. Electric energy feedback load. When choosing a power supply, customers should choose different power supply capacities according to the nature of the load.

(2) Selection of variable frequency power supply capacity The series of power supplies produced by our company have no special requirements for general load types, and can be adapted to resistive, inductive, capacitive, rectifying and mixed loads. The technical parameters given in the sample are tested under rated conditions and resistive load conditions. Under rated conditions, the power supply can run for a long time. However, considering the fluctuation of grid voltage, load current crest factor, short-term overload and other factors, when selecting the power supply capacity, a proper margin should be left. The suggestions are as follows:

(1) Resistive load: power supply capacity =1.1×load power

(2) Resistance-inductance or resistance-capacitance load: power supply capacity =1.1× apparent power of the load

(3) Motor load: When the motor load is started directly, the starting impulse current is about 5 to 7 times the rated current, and the starting time is generally within 2 seconds. The overload capacity of this series of power supply in 2 seconds is twice, beyond this range, the power supply will be overload protected. Therefore, considering the starting capacity, it is recommended that the power supply capacity should be 3 times of the motor power for the direct-starting motor load. Otherwise, take soft start measures, or specify when ordering.

(4) Rectified load: The input circuit includes a rectifier diode (or thyristor) and a filter capacitor. If the input circuit does not have a soft start device, the load can be regarded as a short circuit at the moment the input switch is closed, which will generate a large inrush current. Lead to power supply overcurrent protection. If a large starting inrush current often occurs, it will also have an adverse effect on the load circuit. Therefore, it is recommended that the user's rectifier load input circuit should adopt soft starting measures to limit the starting current. The overcurrent protection threshold of this series of power supplies is about 4 to 5 times the rated value, and the endurance time is about IO milliseconds. The power supply can withstand the inrush current within this range. Since the rectified load current is a pulse current, the current crest factor can reach 3-3.5 times, so it has a certain influence on the output voltage waveform of the power supply and the long-term operating output. The degree of influence is determined by the load current crest factor. Generally, when the load current crest factor> At 2 o'clock, the power supply capacity is selected by the following formula:

               　　　　　　      Load current crest factor

        battery capacity＝------------------------------ × Load apparent power

                   　　  　　　　　　          2

If the rectifier load is mixed with other loads that require higher voltage waveforms, the power supply margin should be increased on the basis of the above.

(5) For mixed loads, please select comprehensively according to the proportion of different loads. (6) Electric energy feedback loads, such as reversible motors and speed-regulated motor loads. The AF series power supply produced by our company needs special devices. When the reversible motor is suddenly When the direction is changed, a large back electromotive force will be generated internally, which can easily damage the power supply. When selecting a power supply in the motor, the power supply should have a bleeder circuit device, and the customer must give special instructions when ordering.

. Power supply voltage, power frequency

Except for some products, the power supply voltage and voltage frequency are AC220V, 40HZ-140 HZ when the product leaves the factory: If you need to change to the power supply voltage of the area used or special usage requirements, please specify when ordering.