RU2218659C2 - Bipolar signal shaping device - Google Patents

Abstract

FIELD: bipolar pulse shape defibrillators and high-power bipolar electric pulse shapers. SUBSTANCE: device has series- connected cells for shaping positive- and negative-polarity signals, one or more cells for each polarity; each cell has electrical energy storage and electronic controlled switch handling this energy; bypass electronic controlled switch incorporating backward diode is connected in each cell of both polarities in parallel with leads of respective cell; for shaping positive-polarity signal mentioned bypass switch incorporated in each cell and provided with backward diode is connected to negative-polarity switching control circuit for closing it at positive polarity of signal being shaped; for shaping negative-polarity signal controlled bypass electronic switch of each cell incorporating backward diode is connected to positive-polarity signal switching control circuit for closing it at positive polarity of signal being shaped; positive-polarity signal shaping control circuit functions to control on-operation of controlled switch of each cell for shaping positive-polarity signal; negative-polarity signal shaping control circuit is used to control on-operation of electronic control switch of each cell for shaping negative-polarity signal. EFFECT: simplified design and reduced cost of device. 1 cl, 5 dwg

Description

 Devices for generating a bipolar signal can be used in defibrillators with a bipolar pulse shape, formers of powerful bipolar electric pulses.

A known bipolar signal generation circuit using a unipolar signal conditioner, which is connected to the load through a bridge polarity switch (H-bridge). For example, a bridge polarity switching circuit appears in US Pat. No. 6,208,895; 6,175,765; 6,097,982; 6,041,254; 5,824,017 and 5,741,306. When generating a powerful signal with a voltage of several kilovolts and a current of tens of amperes, the following solutions can be used to build a bridge circuit:
1. Use powerful high-voltage electronic keys in each arm;
2. Compose the shoulders of the bridge from series-connected keys to a lower voltage.

 In the case of the first option, expensive electronic devices are used. With the second option, inexpensive mass-produced power electronics devices designed for voltages of 400 ... 600 V can be used, but there is a problem of voltage equalization on series-connected electronic switches, which reduces the efficiency of their use.

 The prototype is the scheme presented in US patent 6,097,982 (FIG. 8 and FIG. 9). This circuit uses a unipolar signal conditioner (FIG. 8), composed of series-connected power cells with electric energy storage devices (polar electric capacitors), controlled by keys (thyristor) and reverse diodes. To obtain a bipolar signal, the output of a unipolar signal conditioner is connected to a bridge switching circuit (FIG.9), in the diagonal of which the load is switched on. Each arm of the bridge consists of series-connected controlled keys (IGBT) with parallel-connected resistors for voltage equalization when the keys are open.

 The disadvantage of this scheme is the need to use a large number of power switches, most of which are used exclusively for switching polarity, the need to use voltage equalization circuits on the key elements of the open shoulders of the bridge. In addition, the circuit uses discrete high-power high-speed reverse diodes, which increase the cost of the product. The high-voltage bridge circuit for switching polarity, used in the prototype, requires the inclusion of several series-connected electronic controlled keys in one bridge, to equalize the voltages on which, with an open shoulder, resistors are used, through which currents must flow, the value of which should be significantly higher than the leakage currents of electronic keys .

 In the inventive device for the formation of a bipolar signal, the voltage on the electronic switches controlling the polarity switching does not exceed the voltage on the cell energy storage device, and there is no need for voltage equalization. Also, since the electronic keys controlling the polarity switching contain integrated reverse diodes, there is no need to use discrete reverse diodes, as is done in the prototype. Also, if the same electronic keys are used in the prototype circuit to control pulse formation and in the bridge circuit, the number of similar electronic keys in the bipolar signal generation device is less than or equal to the number of keys in the prototype bridge circuit (the average voltage on the keys in the bridge circuit should be lower than due to the uneven voltage on the disconnected shoulders of the bridge) and at least one and a half times less than in the entire prototype circuit.

 The problem to which the invention is directed, is to simplify and reduce the cost of the device.

 The essence of the invention lies in the fact that the device uses a series connection of cells to form a signal of positive and negative polarity, in which bypass circuits connected to the terminals of these cells and including integrated ones are closed to pass a current of positive polarity in the cells to form a signal of negative polarity. reverse diodes, and to pass a current of negative polarity in the cells to form a signal of positive polarity are closed I have bypass electronic keys connected in parallel to the terminals of these cells and including integrated reverse diodes, and in this way current flows in two directions through the cells connected in series. As a result, the functional combination of the signal conditioning circuit and the polarity switching circuit is ensured and an exception is made from the circuit of powerful high-speed reverse diodes in a discrete design and a decrease in the total number of power electronic keys.

 Figure 1 shows a device for generating a bipolar signal.

 In FIG. Figure 2 shows the current path during the formation of a signal of positive polarity when the switch key of the energy storage cell of the signal generation cell of positive polarity is closed. Figure 3 shows the current path during the formation of a positive polarity signal when the switching key of the energy storage cell of the positive polarity signal generation cell is open. Figure 4 shows the current path when generating a signal of negative polarity, when the switch key of the energy storage cell of the formation of a signal of negative polarity is closed. Figure 5 shows the current path when generating a signal of negative polarity, when the switch key of the energy storage cell of the formation of a signal of negative polarity is open.

 Figure 1 shows a device for generating a bipolar signal. The device consists of one or more cells of the formation of a signal of positive polarity (1, 2) and one or more cells of the formation of a signal of negative polarity (3, 4). Load 5 is connected to the terminals 6, 7 of the device. The signal generation cells include an electric energy storage device (8, 9, 10, 11), an electronic controlled key, a switching energy storage device for a load (12, 13, 14, 15), a bypass electronic controlled key with an integrated reverse diode (16, 17, 18, 19).

 The positive polarity switching control circuit 20 with a positive polarity of the signal supplies the closure signals of one or more bypass keys of the negative polarity signal generation cells 18, 19 to provide current flow in the direction from the output of circuit 6 to the output of circuit 7. The control circuit for generating a positive polarity signal 21 controls the inclusion one or more electronic controlled keys (12, 13), switching energy storage devices (8, 9) to the load in the positive pulse generation cells polarity (1, 2), while the bypass electronic controlled keys of these cells are open. Integrated reverse diodes of bypass electronic controlled keys 16, 17 serve to ensure the flow of current with open electronic controlled keys 12,13, switching energy storage devices to the load.

 A negative polarity switching control circuit 22 with a positive pulse polarity provides closure signals for one or more bypass keys of the positive polarity pulse generating cells 16, 17 to ensure that the current flows in the direction from the output of circuit 7 to the output of circuit 6. The control circuit for generating a negative polarity pulse 23 controls the inclusion one or more electronic controlled keys (14, 15), switching the energy storage device (10, 11) to the load in the cells of the negative pulse formation polarity (3, 4), while the bypass electronic controlled keys of these cells are open. The integrated reverse diodes of the bypass electronic controlled keys 18, 19 are used to provide current flow when the electronic controlled keys 14, 15 are open, switching energy storage devices to the load.

 The operation of the device for generating a bipolar signal is illustrated by the example with one cell of signal formation of positive polarity and one cell of signal formation of negative polarity. The energy storage devices in the cells are charged up to a voltage of 500 V, which ensures the use of power electronic keys for mass use. Figure 2 ... 5 shows the path of the current generating the signal at various possible states of the switching elements of the device.

 In FIG. 2 shows the current path when generating a signal of positive polarity, when the switching key of the energy storage 13 of the cell generating the signal of positive polarity 2 is closed. Current flows from the lower terminal of load 5 through the bypass key 18 of the negative polarity signal generating cell 3 (the switching key of the energy storage cell 14 of the negative polarity signal generating cell is open), through the energy storage 9 of the positive polarity signal generating cell, the switching key of the energy storage cell 13 of the positive signal generating cell polarity to the top terminal of the load.

 In FIG. 3 shows the current path when generating a signal of positive polarity, when the switching key of the energy storage 10 of the cell generating the signal of positive polarity 2 is open. Current flows from the lower terminal of load 5 through the bypass key 18 of the negative polarity signal generating cell 3 (the switching key of the energy storage 14 of the negative polarity signal generating cell is open), through the reverse diode of the bypass key 17 of the positive polarity signal generating cell to the upper terminal of the load.

 In FIG. 4 shows the current path when generating a signal of negative polarity when the switching key of the energy storage 14 of the cell for generating a signal of negative polarity 3 is closed. Current flows from the top output of load 5 through the bypass key 15 of the positive polarity signal generation cell 2 (the switching key of the energy storage cell 13 of the positive polarity signal generation cell is open), through the energy storage 14 of the negative polarity signal generation cell, the switching key of the energy storage cell 14 of the negative polarity signal cell polarity to the lower terminal of the load.

 In FIG. 5 shows the current path when generating a signal of negative polarity when the switching key of the energy storage 14 of the cell for generating a signal of negative polarity 3 is open. The current flows from the top terminal of load 5 through the bypass key 17 of the positive polarity signal generating cell 2 (the switching key of the energy storage 13 of the positive polarity signal generating cell is open), through the reverse diode of the bypass key 18 of the negative polarity signal generating cell to the lower terminal of the load.

 The device for generating a bipolar signal is used in a defibrillator developed at the Moscow State Institute of Electronic Technology for the Federal State Unitary Enterprise Production Association Ural Optical and Mechanical Plant (Yekaterinburg). The device for generating a bipolar signal has been tested on several models.

Sources of information
1. US patent 6208895, CL A 61 N 1/39, published 03/27/2001.

 2. US patent 6175765, CL. A 61 N 1/39, published on 16.01.2001.

 3. US patent 6041254, CL. A 61 N 1/39, published 03/21/2000.

 4. US patent 5824017, CL. A 61 N 1/39, published on 20.10. 1998.

 5. US patent 5741306, CL A 61 N 1/39, published on 04/21/1998.

 6. US patent 6097982, CL. A 61 N 1/39 ,, published 01.08.2000 - prototype.

Claims (1)

A device for generating a bipolar signal, containing series-connected cells for generating a signal, including electric energy storage devices and electronic keys for switching them, characterized in that the cells for generating a signal are made in the form of one or more separate cells for generating a signal of positive polarity and for generating signal of negative polarity, a bypass electron is included in each of the cells of both polarities in parallel with the terminals of the corresponding cell a controlled key with a reverse diode, while a bypass electronic controlled key with a reverse diode of each cell for generating a signal of positive polarity is connected to a switching circuit of negative polarity with the possibility of its closure with a negative polarity of the generated signal, and a bypass electronic controlled key with a reverse diode each cells for generating a signal of negative polarity is connected to a positive polarity switching control circuit with the possibility of Sintered its circuit when the positive polarity signal is generated, the control signal generation circuit of a positive polarity controls the switching of the electronic key managed for each cell of the signal of positive polarity, negative control circuit forming the polarity signal controls the controllable switch of the electronic switching each cell to form a negative polarity signal.

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