Mr system with improved protection against cardiac stimulation

A magnetic resonance (MR) system comprising:

• a system controller;
• and
• a gradient power amplifier,
• wherein the gradient power amplifier comprises:
• at least one output stage that is connectable to a gradient coil;
• and
• four switching elements connected to one another as an H-bridge that are switched by respective power drivers, and
• wherein the switching elements attached to a common first pole of a voltage supply are configured to be switched by non-inverting power drivers, and
• wherein the switching elements attached to a common second pole of the voltage supply are configured to be switched by inverting power drivers.

In a non-transitory computer-readable storage medium that stores instructions executable by a magnetic resonance (MR) system to operate the MR system with a gradient power amplifier that has at least one output stage that is connectable to a gradient coil and has four switching elements connected to one another as an H-bridge that are switched by respective power drivers with which, to operate the gradient coil, in alternation, the instructions comprise:

• switching the switching elements attached to a common first pole of a voltage supply to conductive and switching the switching elements attached to a common second pole of the voltage supply to blocking;
• and
• switching the switching elements attached to the common first pole of the voltage supply to blocking and switching the switching elements attached to the common second pole of the voltage supply to conductive,
• wherein the switching elements attached to the first pole are switched by non-inverting power drivers, and
• wherein the switching elements attached to the second pole are switched by inverting power drivers.