Abstract:
A box (SCB1) for combining n strings or m arrays of a DC part of a PV plant comprises a plurality of n DC inputs (21, 22, 23, 24) for electrical connection to the n strings or to a plurality of m DC inputs for electrical connection to the m arrays, at least n or m DC direction sensors for detecting the direction of direct currents (I S1 , I S2 , I S4 , I R ) conducted in the n or m DC inputs (21, …, 24) and a combiner control unit (SCCU). The DC direction sensors communicate their output signals to the combiner control unit. The combiner control unit communicates a first tripping signal to first switching units associated to the DC direction sensors for opening n-1 or m-1 of the n or m pairs of first switching units in order to interrupt the direct currents (I S1 , I S2 , I S4 ) between each of n-1 or m-1 DC inputs (21, 22, 24) and the two busbars when in a remaining one (23) of the DC inputs the direct current changes from a forward (I S3 ) to a first reverse current (I R ). This allows a fast localization and removal of a faulty string or array without any remarkable interruption of the PV plant and with small-sized switching units, typically with hybrid breakers. Thus the PV plant is distinguished by a high yield rate and a high reliability and can be installed and operated in a cost-efficient manner. Furthermore for reason of the small-sized switching units the combiner box can be realized as rail arrangement with a plurality of box-shaped modules which are attached to the rail arrangement.
Abstract:
The method of the invention is performed in a combiner box of a DC part of a PV plant before start-up and forms a measuring circuit in which at least one of the direction of a DC current, the polarity of a voltage or a ground fault is measured and in which the result of the measurement is used to determine an installation error in the DC part.
Abstract:
A box (SCB1) for combining n strings or m arrays of a DC part of a PV plant comprises a plurality of n DC inputs (21, 22, 23, 24) for electrical connection to the n strings or to a plurality of m DC inputs for electrical connection to the m arrays, at least n or m DC direction sensors for detecting the direction of direct currents (IS1, IS2, IS4, IR) conducted in the n or m DC inputs (21, …, 24) and a combiner control unit (SCCU). The DC direction sensors communicate their output signals to the combiner control unit. The combiner control unit communicates a first tripping signal to first switching units associated to the DC direction sensors for opening n-1 or m-1 of the n or m pairs of first switching units in order to interrupt the direct currents (IS1, IS2, IS4) between each of n-1 or m-1 DC inputs (21, 22, 24) and the two busbars when in a remaining one (23) of the DC inputs the direct current changes from a forward (IS3) to a first reverse current (IR). This allows a fast localization and removal of a faulty string or array without any remarkable interruption of the PV plant and with small-sized switching units, typically with hybrid breakers. Thus the PV plant is distinguished by a high yield rate and a high reliability and can be installed and operated in a cost-efficient manner. Furthermore for reason of the small-sized switching units the combiner box can be realized as rail arrangement with a plurality of box-shaped modules which are attached to the rail arrangement.
Abstract:
The invention concerns a switching device (24) for a high voltage power system and an arrangement comprising such a switching device. The switching device comprises a first semiconductor switching element (26) capable of being turned off and having a first gate (G1) and a first and a second current conduction terminal (CCT1, CCT2) and a second switching element (26) capable of being turned on and comprising an electron tube with a second gate (G2) and a first and second electrode (E1, E2). The switching elements (26, 28) are series-connected with the first electrode (E1) connected to the second current conduction terminal (CCT2) with the first current conduction terminal (CCT1) and the second electrode (E2) providing connections to the power system and the switching elements being jointly operable for breaking or making a current path between the second electrode (E2) and the first current conduction terminal (CCT1).
Abstract:
An electrical switch, in particular a medium or high voltage switch, comprises two movable coils {8a, 8b) as well as two movable metal parts (10a, 10b), with the coils (8a, 8b) being arranged, e.g., between the metal parts (10a, 10b). Each coil (8a, 8b) is mechanically connected to the metal part (10a, 10b) on the opposite side and able to push the same away from the center of the assembly. The two coils (8a, 8b) can be arranged electrically in parallel to each other. Upon application of a current pulse to the coils (8a, 8b), the coils (8a, 8b) are attracted to each other due to their parallel magnetic fields, while the metal plates (10a, 10b) are accelerated outwards due to eddy currents. These two effects combine to separate the metal (10a, 10b) parts quickly.
Abstract:
A box (SCB1) for combining n strings or m arrays of a DC part of a PV plant comprises a plurality of n DC inputs (21, 22, 23, 24) for electrical connection to the n strings or to a plurality of m DC inputs for electrical connection to the m arrays, at least n or m DC direction sensors for detecting the direction of direct currents (IS1, IS2, IS4, IR) conducted in the n or m DC inputs (21, …, 24) and a combiner control unit (SCCU). The DC direction sensors communicate their output signals to the combiner control unit. The combiner control unit communicates a first tripping signal to first switching units associated to the DC direction sensors for opening n-1 or m-1 of the n or m pairs of first switching units in order to interrupt the direct currents (IS1, IS2, IS4) between each of n-1 or m-1 DC inputs (21, 22, 24) and the two busbars when in a remaining one (23) of the DC inputs the direct current changes from a forward (IS3) to a first reverse current (IR). This allows a fast localization and removal of a faulty string or array without any remarkable interruption of the PV plant and with small-sized switching units, typically with hybrid breakers. Thus the PV plant is distinguished by a high yield rate and a high reliability and can be installed and operated in a cost-efficient manner. Furthermore for reason of the small-sized switching units the combiner box can be realized as rail arrangement with a plurality of box-shaped modules which are attached to the rail arrangement.
Abstract:
The method of the invention is performed in a combiner box of a DC part of a PV plant before start-up and forms a measuring circuit in which at least one of the direction of a DC current, the polarity of a voltage or a ground fault is measured and in which the result of the measurement is used to determine an installation error in the DC part.
Abstract:
High voltage switching device comprising an outer casing, and at least two vacuum interrupters electrically connected in series to each other and having each a fixed contact and an associated movable contact. An actuating mechanism actuates the movable contacts between a first closed position in which they are connected to the corresponding fixed contacts, and a second open position in which they are separated therefrom. The actuating mechanism comprises a single drive unit supplying the energy required to move the movable contacts, and transmission means transmitting the energy required to the movable contacts; the transmission means comprise at least one transmission belt or chain drive which is actuated by the drive unit and operatively links the movement of the movable contacts.
Abstract:
A DC circuit breaker (10) is provided, comprising a pair of arcing contact members (20a, 20b) for holding an arc (22); an interaction element (40), adapted for interacting with the arc (22) in dependence of whether the arc (22) is in a first state (22a) or in a second state (22b) such that due to the interaction element (40) the arc voltage drop in the first state (22a) is lower than the arc voltage drop in the second state (22b); a resonance branch (30) coupled in parallel to the contact members (20a, 20b) thereby forming a resonance circuit adapted for letting a resonance branch current I r oscillate thereby inducing oscillations of an arc current I a , wherein the resonance branch (30) comprises a coupling element (32) for coupling the resonance branch (30) with the arc (22), such that the arc (22) is brought to the first state (22a) when the current Ir in the resonance branch (30) has a first direction, and that the arc (22) is brought to the second state (22b) when the current I r in the resonance branch (30) has a second direction.