Abstract

The applicaton generally relates to apparatus for driving high voltage power switching devices such as IGBTs. An aspect provides a method of adding a sensing capability to a device driver for driving at least one high voltage power switching device of a power switching apparatus having device side circuitry comprising said at least one device and said driver and having control side circuitry comprising a driver controller, the device driver arranged to be coupled to a said driver controller by a communications link, the device driver arranged to drive said at least one device on or off in response to a switching signal received on said communications link from the driver controller, the device driver further arranged to transmit an acknowledge signal to said driver controller in response to said received switching signal, said acknowledge signal detectable at said driver controller as a valid said acknowledge signal, the method comprising: providing a sense circuit to output an indication of a condition of said device side circuitry; providing a modulation circuit to modulate a said acknowledge signal dependent on said condition indication prior to said transmission such that said modulated acknowledge signal is said acknowledge signal to be transmitted by said device driver to said driver controller in response to said received switching signal and detectable at said driver controller as a valid said acknowledge signal.

IPC Classes  ?

• H03K 17/18 - Modifications for indicating state of switch

Abstract

We describe a controller (130) for controlling a power semiconductor switching device (132) into a selected one of a plurality of states, the states including a fully-off state, a saturated-on state, and at least one intermediate state. The switching device controller includes a voltage sense input (142) to sense a voltage on the device; a current sense input (current feedback) to sense a current passing through the device; a negative feedback control circuit (138) coupled to the sense inputs, a control output (136) to provide to the power semiconductor switching device a drive signal with a response dependent on one or more adjustable parameters; and a circuit controller (140) to control the adjustable parameters responsive to state command data, to control the switching device into a selected state, in particular by controlling an effective resistance of the device. Preferred intermediate states include an active low current state and an active low voltage state.

IPC Classes  ?

• H03K 17/18 - Modifications for indicating state of switch
• H03K 17/082 - Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit
• G08C 15/06 - Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path successively, i.e. using time division
• H02J 13/00 - Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the networkCircuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
• G08C 25/02 - Arrangements for preventing or correcting errorsMonitoring arrangements by signalling back from receiving station to transmitting station
• H03K 17/12 - Modifications for increasing the maximum permissible switched current
• H03K 17/10 - Modifications for increasing the maximum permissible switched voltage
• H03K 17/16 - Modifications for eliminating interference voltages or currents

Abstract

We describe a system for controlling very large numbers of power semiconductor switching devices (132) to switch in synchronisation. The devices are high power devices, for example carrying hundreds of amps and/or voltages of the order of kilovolts. In outline the system comprises a coordinating control system (110, 120), which communicates with a plurality of switching device controllers (130) to control the devices into a plurality of states including a fully-off state, a saturated-on state, and at least one intermediate state between the fully-off and saturated-on states, synchronising the devices in the at least one intermediate state during switching.

IPC Classes  ?

• H02M 1/088 - Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
• H03K 17/12 - Modifications for increasing the maximum permissible switched current
• H03K 17/10 - Modifications for increasing the maximum permissible switched voltage
• H03K 17/16 - Modifications for eliminating interference voltages or currents

Abstract

We describe a fault-tolerant power semiconductor switching device control system (100), the control system comprising: a coordinating control system (110); and a plurality of switching device controllers (120) each coupled to said coordinating control system and each configured to control a respective power semiconductor switching device (130); wherein said coordinating control system is configured to send real time switching control data to said switching device controllers to control switching of said power semiconductor switching devices, and to receive real time acknowledgement data from said switching device controllers; wherein a said switching device controller is configured to receive said real time switching control data from said coordinating control system, to control a said power semiconductor switching device responsive to said real time switching control data, and to provide said real time acknowledgement data confirming said switching device control to said coordinating control system; and wherein said coordinating control system is further configured to control further switching of said power semiconductor switching devices responsive to said real time acknowledgement data.

IPC Classes  ?

• H03K 17/18 - Modifications for indicating state of switch
• H03K 17/082 - Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit
• G08C 15/06 - Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path successively, i.e. using time division
• H02J 13/00 - Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the networkCircuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network

Abstract

We describe techniques suitable for communicating switching data in a control system controlling, for example, kilovolts at hundreds of amps. The system comprises a central controller (110) coupled to sub - controllers (120) and thence to a plurality of switching device controllers (SDs,130), preferably in a tree - structure, each SD controlling a power semiconductor switching device such as an IGBT. The method includes formatting switching control data as one or more switching control data packets comprising data for controlling switching of a combination of the devices, sending these from the central controller to the switching device controllers, at the SDs formatting state data representing states of the switching devices controlled in combination into a plurality of acknowledgement data packets, and sending these back to the central controller. The techniques may be employed for controlling the synchronised switching of, potentially, tens, hundreds or thousands of power semiconductor switching devices.

IPC Classes  ?

• H03K 17/18 - Modifications for indicating state of switch
• H03K 17/082 - Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit
• G08C 15/06 - Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path successively, i.e. using time division
• H02J 13/00 - Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the networkCircuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
• G08C 25/02 - Arrangements for preventing or correcting errorsMonitoring arrangements by signalling back from receiving station to transmitting station

Abstract

This invention generally relates to voltage balancing among series - connected power switching devices comprising one or more insulated gate bipolar transistor (IGBT), and more particularly to a method controlling sharing of voltage among series - connected power switching devices, wherein at least one said device is an insulated gate bipolar transistor (IGBT), the method comprising: controlling the IGBT dependent on a reference signal (Vref) and collector or emitter voltage of the IGBT such that during an off period of said IGBT said reference signal limits an absolute value of collector-emitter voltage of said IGBT to be within a range; and control to temporarily change during said limiting said reference signal from an initial value (Vclamp) to a temporary clamp value (Vtemporal clamp) to reduce said range, said change when each of said devices is in a substantially non-conducting state (off).

IPC Classes  ?

• H03K 17/082 - Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit
• H03K 17/10 - Modifications for increasing the maximum permissible switched voltage