摘要:
Zur Ermittlung der Belastbarkeit einer über einen Wechselrichter (4) und einen Netzschalter (11) einem Wechselstromnetz (3) mit einer vorgegebenen Netzfrequenz zuschaltbaren Gleichspannungsquelle (2) wird eine Eingangsgleichspannung (U Q , U z ) bei geöffnetem Netzschalter (11) und bei einer einen Vier-Quadrantenbetrieb ermöglichenden Ansteuerung des Wechselrichters (4) erfasst. Dabei wird der Wechselrichter (4) bei geöffnetem Netzschalter (11) so angesteuert, dass er die Eingangsgleichspannung (U Q , U Z ) auf eine gegenüber der Netzfrequenz abweichende Prüffrequenz wechselrichtet, um eine auf die Gleichspannungsquelle (2) einwirkende Prüflast über den Eigenbedarf des Wechselrichters (4) bei der Netzfrequenz hinaus zu erhöhen.
摘要:
A stacked voltage source inverter having separate DC sources is described herein. This inverter is applicable to low or medium voltage, low to medium power applications such as photovoltaic utility interface systems, battery storage application such as peak shaving with renewables, motor drive applications and for electric vehicle drive systems. The stacked inverter consists of at least one phase wherein each phase has a plurality of low voltage full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with fast switching and small low pass AC output filter. A system controller controls operating parameters for each inverter. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.
摘要:
In the field of voltage source converters which provide high voltage direct current (HVDC) power transmission and reactive power compensation there is a need for an improved power electronic module which exhibits high efficiency, provides a safe failure mode, and is tolerant of faults. A power electronic module (30; 70), for use in a chain-link converter of a voltage source converter providing high voltage direct current power transmission and reactive power compensation, comprises a first set (32) of series-connected switching elements connected in parallel with an energy storage device (34). The first set (32) of series-connected switching elements includes a first latching switching element (38) and a first non-latching switching element (40).
摘要:
At the time of activation and powe flow inversion of a DC power transmission system, a quick transition to the steady state is achieved. A control device includes constant voltage control circuits 11A, 11B, constant current control circuits 12A, 12B, minimum value selecting circuits 13A, 13B, a DC current setter 16, and current margin setters 15A, 15B. When a power converter 5B serves as a inverter, the DC current setter 16 increases a DC current setting value Idp, the current margin setter 15B increases a current margin ΔId 2 for the power converter 5B, and the constant current control circuits 12A, 12B output respective control angles to the power converter 5B based on the difference between the current margin ΔId 2 and the DC current setting value Idp and the input that is a DC current Id 2 .
摘要:
A stacked voltage source inverter having separate DC sources is described herein. This inverter is applicable to low or medium voltage, low to medium power applications such as photovoltaic utility interface systems, battery storage application such as peak shaving with renewables, motor drive applications and for electric vehicle drive systems. The stacked inverter consists of at least one phase wherein each phase has a plurality of low voltage full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with fast switching and small low pass AC output filter. A system controller controls operating parameters for each inverter. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.