逆变器外文文献及翻译

InverterInverter 1 1IntroductionIntroduction An inverter is an electrical device that converts direct current DC to alternating current AC; the converted AC can be at any required voltage and frequency with the use of appropriate transers, switching, and control circuits.Solid-state inverters have no moving parts and are used ina wide range of applications, fromsmall switching power supplies in computers, to large electric utility high-voltage direct current applications that transport bulk power. Inverters are commonly used to supply AC power from DC sources such as solar panels or batteries. There are two main types of inverter. The output of a modified sine wave inverter is similar to a square wave output except that the output goes to zero volts for a time before switching positive or negative. It is simple and low cost and is compatible with most electronic devices, except for sensitive or specialized equipment, for example certain laser printers. A pure sine wave inverter produces a nearly perfect sine wave output 3 total harmonic distortion that is essentially the same as utility-supplied grid power. Thus it is compatible with all AC electronic devices. This is the type used in grid-tie inverters. Its design is more complex, and costs 5 or 10 times more per unit powerThe electrical inverter is a high-power electronic oscillator. It is so named because early mechanical AC to DC converters were made to work in reverse, and thus were “inverted“, to convert DC to AC.The inverter pers the opposite function of a rectifier. 2 2ApplicationsApplications 2.12.1DC power source utilizationDC power source utilization An inverter converts the DC electricity from sources such asbatteries, solar panels, or fuel cells to AC electricity. The electricity can be at any required voltage; in particular it can operate AC equipment designed for mains operation, or rectified to produce DC at any desired voltageGrid tie inverters can feed energy back into the distribution network because they produce alternating current with the same wave shape and frequency as supplied by the distributionsystem.Theycanalsoswitchoffautomaticallyintheeventofa blackout.Micro-inverters convert direct current from individual solar panels into alternating current for the electric grid. They are grid tie designs by default. 2.22.2Uninterruptible power suppliesUninterruptible power supplies An uninterruptible power supply UPS uses batteries and an inverter to supply AC power when main power is not available. When main power is restored, arectifier supplies DC power to recharge the batteries. 2.32.3Induction heatingInduction heating Inverters convert low frequency main AC power to a higher frequency for use in induction heating. To do this, AC power is first rectified to provide DC power. The inverter then changes the DC power to high frequency AC power. 2.42.4HVDC power transmissionHVDC power transmission With HVDC power transmission, AC power is rectified and high voltag