Sma Solar Technology Ag

Andreas Knobloch

Klaus Rigbers

Thomas Wappler

Pablo Ignacio Correa Vasquez

Pablo Ignacio Correa Vasques

Gerrit Braun

Matthias Rehbein

An inverter with a rated power of at least 3 kVA includes a first assembly which includes a first printed circuit board and a DC/AC converter stage, and a second assembly which includes a second printed circuit board and an EMC filter for the DC/AC converter stage. The first printed circuit board is mounted on a heat sink and lies substantially flat on the heat sink, and the DC/AC converter stage has converter components which comprise power semiconductors, chokes and link circuit capacitors. The chokes and the link circuit capacitors are arranged together on one side of the first printed circuit board, and the heat sink is arranged on the opposite side of the first printed circuit board, and the chokes and/or the power semiconductors are thermally connected to the heat sink via the first printed circuit board and a thermally conductive material arranged between the first printed circuit board and the heat sink. The second printed circuit board is arranged on the side of the first printed circuit board opposite the heat sink, and a metal sheet is arranged between the first assembly and the second assembly, and the second printed circuit board is mounted on the metal sheet.

Inverter of compact design

A method is disclosed for stabilizing a DC voltage in a DC grid that includes a DC bus connected to a higher-order grid and to which an energy generating system and at least one load are connected.

Method for stabilizing the DC voltage in a DC grid, and DC-to-DC converter for connecting a PV generator to a DC grid

An energy generation system provides balancing power for an AC voltage grid, and comprises a photovoltaic generator and an energy store, wherein the energy generation system exchanges a total electrical power with the AC voltage grid (), wherein the total power exchanged is set as a function of a current maximum PV power, a predefinable basic PV power between zero and the maximum PV power and a provided or requested balancing power. When no balancing power is requested: a total basic power, which comprises the basic PV power can be fed in; When a negative balancing power is requested: the PV power can be reduced compared to the basic PV power; When a positive balancing power is requested: a battery power can be drawn from the energy store if the requested positive balancing power is greater than the difference between the maximum PV power and the basic PV power.

Method for providing control power for an alternating voltage system by means of an energy-generating plant

A method for operating an energy generation system containing a photovoltaic generator and an inverter, wherein electric power is transferred between the inverter and an AC voltage grid, and wherein the transferred electric power comprises an active power (P) and a reactive power (Q) is disclosed. The method includes operating the photovoltaic generator, in a first operating mode, at a maximum active power point (MPP) by way of the inverter, and setting the active power (P) of the photovoltaic generator via the inverter in a second operating mode depending on a grid frequency instantaneous value (f) and on a grid frequency rate of change (df/dt), and in the second operating mode, setting the reactive power (Q) depending on a grid voltage instantaneous value (U) and on a grid voltage rate of change (dU/dt).

Method for operating an energy generating system, and inverter for an energy generating system

A method and system for operating an inverter, which has a terminal with four conductor connectors for connection of the inverter to three outer conductors and to a neutral conductor of an AC voltage grid is disclosed. The method includes determining a connection configuration of the inverter to the AC voltage grid by actuating switching elements of a bridge circuit of the inverter to generate a zero-phase sequence system having a zero-phase sequence system current, and measuring and evaluating output currents of the inverter with respect to the zero-phase sequence system current. The method also includes identifying a presence of a connection of the neutral conductor to a conductor connector provided for connection to the neutral conductor when the zero-phase sequence system current exceeds a prescribed threshold value and identifying that the neutral conductor is not connected to the conductor connector provided for connection to the neutral conductor otherwise.

Inverter with identification of neutral connection

In order to reduce spurious emissions of a current converter or voltage converter having at least one power switch which is actuated with an actuating signal, wherein each actuating signal comprises switch-on pulses spaced apart from one another, and wherein pulse widths of the switch-on pulses are modulated in order to meet a specification for a current or a voltage in or at the current converter or voltage converter, the pulse widths are additionally varied more quickly and more strongly than is appropriate for meeting the specification in order to change the spectrum of the spurious emissions. In this context, changes to the pulse widths when they additionally vary compared to the pulse widths that would result only owing to their modulation to meet the specification are made on the basis of successive groups of changes which each extend over a predefined number of successive switch-on pulses and in which a sum of the changes is zero in each case. The successive groups of changes are varied with respect to at least one aspect which is selected from absolute values of the changes, signs of the changes, a sequence of the changes and an extent of the group.

Growing community of inventors

Kassel, Germany

Andreas Knobloch