Abstract: Methods and systems are provided for controlling an electron beam generated by an x-ray tube assembly including a unipolar cathode. In one embodiment, a voltage supplied to the cathode is controlled by a multi-stage switching unit including a first control circuit and a second control circuit. A bias voltage for switching the cathode on is generated by a voltage source of the second control circuit, and a gridding voltage for switching the cathode off is generated by a plurality of voltage sources of the first control circuit. When transitioning between the bias voltage and the gridding voltage and vice-versa, a control strategy is used where the voltage sources of the first control unit are selectively engaged and/or disengaged in a non-consecutive order in accordance with an optimized protocol, to prevent a voltage imbalance between capacitors of different stages of the multi-stage switching unit.

Abstract: A medical imaging system includes an X-ray source configured to emit X-rays. The medical imaging system also includes a high voltage generator configured to provide power to the X-ray source. The medical imaging system further includes a high efficiency power distribution unit configured to receive electrical power from an electrical grid and to store the electrical power, wherein the high efficiency power distribution unit includes an active rectifier configured to regulate a high voltage direct current outputted to components of the medical imaging system including the high voltage generator.

Abstract: Methods and systems are provided for controlling an electron beam generated by an X-ray tube assembly including a unipolar cathode with a long cable between driving electronics of the cathode and the X-ray tube. A voltage supplied to a gridding electrode of the cathode is controlled by a multi-stage switching unit including a first control circuit and a second control circuit. A bias voltage for switching the cathode on is generated by a high precision voltage source of the second control circuit, and a gridding voltage for switching the cathode off is generated by voltage sources of the first control circuit. A time taken to transition between the gridding voltage and the bias voltage is advantageously reduced by decreasing the supplied voltage to a common voltage (e.g., 0 V) in a first step, and then increasing the supplied voltage to the bias voltage or the gridding voltage in a second step.

Abstract: Methods and systems are provided for controlling an electron beam generated by an X-ray tube assembly including a unipolar cathode with a long cable between driving electronics of the cathode and the X-ray tube. A voltage supplied to a gridding electrode of the cathode is controlled by a multi-stage switching unit including a first control circuit and a second control circuit. A bias voltage for switching the cathode on is generated by a high precision voltage source of the second control circuit, and a gridding voltage for switching the cathode off is generated by voltage sources of the first control circuit. A time taken to transition between the gridding voltage and the bias voltage is advantageously reduced by decreasing the supplied voltage to a common voltage (e.g., 0 V) in a first step, and then increasing the supplied voltage to the bias voltage or the gridding voltage in a second step.

Abstract: Methods and systems are provided for controlling an electron beam generated by an x-ray tube assembly including a unipolar cathode. In one embodiment, a voltage supplied to the cathode is controlled by a multi-stage switching unit including a first control circuit and a second control circuit. A bias voltage for switching the cathode on is generated by a voltage source of the second control circuit, and a gridding voltage for switching the cathode off is generated by a plurality of voltage sources of the first control circuit. When transitioning between the bias voltage and the gridding voltage and vice-versa, a control strategy is used where the voltage sources of the first control unit are selectively engaged and/or disengaged in a non-consecutive order in accordance with an optimized protocol, to prevent a voltage imbalance between capacitors of different stages of the multi-stage switching unit.