Circuit arrangement and method for transferring electrical charge between accumulators of an accumulator arrangement including a series circuit of accumulators

A method of transferring electrical charge between accumulators of an accumulator arrangement comprising a series circuit of accumulators, comprising

• measuring accumulator voltages across at least two of the accumulators of the accumulator arrangement by respectively closing a switch connected to each of the at least two of the accumulators and measuring a voltage across an inductive storage element connected to another one of the accumulators,
• selecting at least one of the some accumulators dependent on the measured accumulator voltages,
• taking energy from the accumulator arrangement,
• feeding at least a part of the energy taken from the accumulator arrangement to the at least one selected accumulator, only.

A circuit arrangement for transferring electrical charge between accumulators of an accumulator arrangement comprising a series circuit of accumulators, comprising a number of first series circuits each for connecting in parallel to one of the accumulators, and each comprising a switching element having a load path and a control terminal, and an inductive storage element connected in series to the load path;

• a further series circuit for connecting in parallel to the accumulator arrangement and comprising a further switching element having a load path and a control terminal, and a further inductive storage element connected in series to the load path, the further inductive storage element being inductively coupled to the inductive storage elements of the first series circuits;
• a control circuit comprising a number of first control outputs each of which being connected to the control terminal of one of the switching elements of the first series circuits, and a further control output connected to the control terminal of the further switching element;
• wherein the control circuit further includes a voltage measurement input coupled to the inductive storage elements of one of the first series circuits,
• wherein the inductive storage elements of the first series circuits are inductively coupled to one another, and
• wherein the control circuit is configured to measure the voltage across the inductive storage element of another one of the first series circuits when i) the switching element of the one of the first series circuits is open and ii) the switching element of the other one of the first series circuits is closed.

A method for transferring electrical charge between accumulators in a circuit arrangement, the circuit arrangement comprising:

• a number of first series circuits each for connecting in parallel to one of the accumulators, and each comprising a switching element having a load path and a control terminal, and an inductive storage element connected in series to the load path;
• a further series circuit for connecting in parallel to the accumulator arrangement and comprising a further switching element having a load path and a control terminal, and a further inductive storage element connected in series to the load path, the further inductive storage element being inductively coupled to the inductive storage elements of the first series circuits;
• a control circuit comprising a number of first control outputs each of which being connected to the control terminal of one of the switching elements of the first series circuits, and a further control output connected to the control terminal of the further switching element,
• the method including:
• closing the switching element of the first series circuit of one of the accumulators,
• measuring a voltage across the one of the accumulators,
• opening the inductive storage element of another series circuit, and
• measuring the voltage across the inductive storage element.