Siemens Healthcare Gmbh

Dirk Schneiderbanger

Helmut Lenz

Lennart Kilian

Daniel Niederlöhner

Matthias Gebhardt

Axel Friedrich

Roland Werner

Daniel Scheit

Christian Plewa

A method for operating an MR system with a gradient pulse amplifier unit that has an end stage connected to a gradient coil with switching elements is provided. The gradient pulse amplifier unit includes a modulator for actuating the switching elements, and lockout switches interconnected in signal paths from the modulator to the switching elements. The gradient pulse amplifier unit includes feeder circuit breakers interconnected in at least some signal paths from the modulator to the switching elements. The circuit breakers are connected in the associated signal paths downstream of the lockout switches. A gradstop unit configured to receive at least one shut-off signal and actuate the lockout switches and the feeder circuit breakers. When the gradstop unit receives a shut-off signal, the gradstop unit actuates the lockout switches to lock out and the feeder circuit breakers to output an actuation signal to the switching elements.

MR system with improved protection against cardiostimulation

A magnetic resonance apparatus with a safety structure for monitoring a safety-related function is provided. The safety structure includes a control path that is configured to control the safety-related function, and a first protect path and a second protect path. The first protect path and the second protect path are configured to acquire a safety-related parameter of the safety-related function. The first protect path is configured to identify a hazardous situation, independently of the control path and the second protect path, based on the safety-related parameter that the first protect path acquires. The second protect path is configured to identify a hazardous situation, independently of the control path and the first protect path, based on the safety-related parameter that the second protect path acquires. The first protect path and the second protect path are each configured to transfer the magnetic resonance apparatus into a safe state in a hazardous situation.

Safety structure of a magnetic resonance apparatus

A method for operating an MR system with a gradient power amplifier having at least one output stage that is connectable to a gradient coil, and having four switching elements connected to one another as an H-bridge includes, to operate the gradient coil, in alternation: 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 a voltage supply to blocking by inverting power drivers; and switching the switching elements attached to a common first pole of a voltage supply to blocking and switching the switching elements attached to a common second pole of a voltage supply to conductive by inverting power drivers. The switching elements attached to the first pole are switched by non-inverting power drivers, and the switching elements attached to the second pole are switched by inverting power drivers.

MR system with improved protection against cardiac stimulation

A circuit arrangement for an MRT system and a method for operating an MRT system are disclosed. The circuit arrangement includes a gradient amplifier having a switch-mode output stage, a regulator device, and a modulator connected therebetween in the circuit. To ensure patient safety, a control path is integrated into a drive path of the circuit arrangement or the MRT system provided for driving a gradient coil, the gradient coil being connected to an output of the switch-mode output stage. The control path includes a limiter stage connected downstream of the regulator device, the modulator, the switch-mode output stage and its supply voltage. The limiter stage is connected in the circuit between the regulator device and an input of the modulator, to limit a control signal output by the regulator device and limit the voltage for the gradient coil provided by the switch-mode output stage at its output.

Growing community of inventors

Langensendelbach, Germany

Dirk Schneiderbanger