Control method for usage of redundancy in case of fault of multi-phase ac rectifier with distributed energy accumulators. RU patent 2507671.

FIELD: electricity.

SUBSTANCE: in accordance with the invention, a subsystem (10) of a branch (T1, …, T6) of valves corresponding to a faulty branch (T1, …, T6) of valves, of a faulty phase module (100) is controlled so that its terminal voltage (U_X21) is equal to zero, and therefore accordingly one subsystem (10) corresponding to this branch (T1, …, T6) of valves of the branch (T1, …, T6) of valves of each faulty phase module (100) is controlled so that their terminal voltages (U_X21) are equal to zero. Thus a control method is produced to use redundancy in case of a fault of a multi-phase AC rectifier with distributed energy accumulators (9), at the same time the generated output voltages (U_L10, U_L20 and U_L30) no longer contain a DC voltage component.

EFFECT: improved method of rectifier control, so that DC voltage components do not manifest themselves in case of a fault in output circuits.

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The invention relates to a method of control multi-phase rectifier AC with distributed energy storage devices according to the generic concept, paragraph 1, of the claims.

From DE 10103031 A1 known rectifier AC with distributed energy storage devices. Equivalent scheme of the AC adapter is presented in figure 1. According to the equivalent circuit, the famous rectifier AC has three-phase module, marked, respectively, as 100. These phase 100 modules on the side of the DC voltage electrical conductivity are connected, respectively, with positive and negative busbar P 0 and N 0 a constant voltage. Between these both teams tires P 0 and N 0 a constant voltage of the inverter, AC with the intermediate circuit voltage would include a concatenation of the two capacitors C1 and C2, which is a drop constant voltage U d . Connection point, both sequentially included capacitors C1 and C2 form a virtual midpoint (neutral) O. Each phase module 100, which forms a branch of the bridge multiphase AC adapter has the upper and lower partial branch of the bridge, which, because partial branches of the bridge are appropriate rectifier valve multiphase AC adapter with distributed energy storage devices, referred to as a branch of the T1 or T3, or KZT5, and T2, or KZT4, or KZT6 valves. Each of these branches T1-T6 gates has included a number of electrically consistently bipolar subsystems 10. In this equivalent circuit shown four subsystems 10. However subsystems number 10 on the branch T1, ..., T6 valves is not restricted to this represented by a number. Each point of connection of the two branches of T1 and T2 or T3 and T4 or T5 and T6 valves phase module 100 forms the conclusion L1 or L2, or L3 side of alternating voltage phase module 100. As in this image rectifier AC has three-phase module 100, their conclusions L1, L2 or L3 AC voltage, also called load conclusions can connect three-phase load, such as a motor three-phase current.

Figure 2 in more detail shows the equivalent circuit of the known forms of performance of bipolar subsystem 10. The schematic device figure 3 is fully functional equivalent version. Both forms of execution of bipolar subsystem 10 are known from DE 10103031 A1. These famous pole subsystem 10 are, respectively, two detachable semiconductor switch 1 and 3, two diodes 2 and 4 and unipolar storage capacitor 9. Both interruptible semiconductor switch 1 and 3 are connected electrically in series, and this scheme serial connection is enabled electrically in parallel savings capacitor 9. With each of interruptible semiconductor switches 1 and 3 electrically connected in parallel to one of the both diodes 2 and 4 in such a way that they in relation to the relevant switchable semiconductor switches 1 and 3 are included antiparallel. Unipolar storage capacitor 9 subsystems 10 either consists of a capacitor or battery of capacitors, consisting of several such condensers, resulting in capacity With 0 . Connection point emitter disable semiconductor switch 1 and anode diode 2 forms terminal X1 subsystem 10. Connection point emitter both interruptible semiconductor switches 1 and 3 and both diodes 2 and 4 forms the second terminal x2 subsystem 10.

In the form of implementation of bipolar subsystem 10 according to figure 3, the junction forms the first terminal X1. Connection point collector disable semiconductor switch 1 and diode cathode 2 forms the second terminal x2 subsystem 10.

In both views, two forms of execution of bipolar subsystem 10 as interruptible semiconductor switches 1 and 3, as shown in figure 2 and 3 apply bipolar transistors (IGBTs (IGBT). Can be used in field-effect transistors with the metal-oxide-semiconductor (MOS). In addition, may apply diode thyristor (GTO) or commutated thyristor units with integral gate (type of IGCT).

According to DE 10103031 A1, bipolar subsystem 10 each phase of the module 100 AC adapter on figure 1, can be managed to switch the switching condition of the I, II and III. In the switching status I switchable semiconductor switch 1 is on and switching off semiconductor switch 3 off. Thus existing at the terminals X1 and x2 terminal voltage U x21 bipolar subsystem 10 is equal to zero. In the switching status II switchable semiconductor switch 1 is off, and switchable semiconductor switch 3 is included. In this state of switching II existing terminal voltage U x21 bipolar subsystem 10 voltage U C , existing at the storage capacitor 9. Able to switch III, both interruptible semiconductor switch 1 and 3 are turned off, and existing at the storage capacitor 9 voltage U C is a constant.

To this rectifier AC distributed drives 9 of energy according to figure 1 could work with the reservation must be guaranteed that the defective subsystem 10 on their terminals X1 and x2 long . This means that the terminal voltage U x21 faulty bipolar subsystem 10, regardless of the direction of flow through the terminals X1 and x2 is zero.

Due to the failure of one of the subsystem 10 interruptible semiconductor switches 1, 3, or related to it, the scheme of management of the correct functioning of this subsystem 10 violated. Other possible reasons for the poor functioning of, among others, are malfunctions in a corresponding schema management interruptible semiconductor switches, their of communications and determination of the measured values. This means that a bipolar subsystem 10 can no longer properly managed in one of the possible States of switching I, II or III. Due to a short circuit subsystem 10 on its findings X1 and x2 this subsystem is no longer supplied no energy. Due to this, consequential damages, such as overheating and burning of further operation of the Converter AC, reliably excluded.

Such a conductive connection type short circuit between the connection terminals X1 and x2 faulty bipolar subsystem 10 must secure manner and without overheating allocate at least working current branch T1, ..., T6 valves phase module 100, which is defective bipolar subsystem 10. In DE 102005040543 A1 indicates how a faulty bipolar subsystem 10 may reliable way to become short. Thus, this famous rectifier AC with distributed energy storage devices can be operated next redundant.

For further explanations assume that storage capacitors 9 all of bipolar subsystems 10 have the same voltage U C . Method for the initial establishment of the state and its maintenance at work is also known from DE 10103031 A1. Figure 4 diagram on time t presents characteristic of the change in the difference of potentials U PL at terminal R phase module 100 towards the network conclusion L. Figure 5 the diagram on time t with the characteristics of the potential difference LN U at terminal L phase module 100 in relation to the potential on the terminal N. According to these characteristics, potentials U PL and U LN , at times t1, t2, t3, t4, t5, t6, t7 or t8 of the eight bipolar subsystems 10 branches T1 and T2 gates, respectively, one subsystem enabled or disabled. Moreover, integration corresponds to the transition from state I switch the switching condition II. Off corresponds to the transition from a state of switching II in the switching condition I. These two diagrams presented, respectively, period of T e a fundamental oscillation characteristics of the potential U LO (6) load output L a virtual middle point Of the phase module 100 AC adapter with distributed drives 9 energy characteristics of potentials U PL and U LN .

From DE 102005045091 A1 known way to control rectifier AC with distributed energy storage devices according to figure 1, with which in case of failure of at least one subsystem phase of the modulus of rectifier AC supports the conditions of symmetry. According to this a known method, first defines a branch of the gates of one of the three phases, in which one or more of bipolar subsystems defective. Each faulty subsystem is managed in a way that the amplitude of the terminal voltage, respectively equal to zero. In every other branch of gates faulty phase module, according to a number of specific bipolar subsystems corresponding to the number of subsystems controlled in such a way that the amplitude of the terminal voltage accordingly equal voltage. This management subsystems in a failed phase module also runs for subsystems branches valves serviceable phase modules.

Figure 7 shows the chart time t features a difference of potentials U PL terminals R phase module 100 relative to output load L phase module 100, and in the lower branch of KZT2, or KZT4, or KZT6, valves phase module 100 one bipolar subsystem 10 faulty. On Fig.8 shows the chart time t features a difference of potentials U LN terminals L on the capacities of terminals N. Of the characteristics of the difference of potentials U PL according Fig.7 you can see that the subsystem 10 each upper branch of the T1, or T3, or KZT5, valves each phase of the module 100 is managed so that its terminal voltage U X21 always voltage U C available at the storage capacitor 9. Due to this, shown for example four subsystems 10 each upper branch of the T1, or T3, or KZT5, valves remain only three subsystems 10, which are connected or disconnected. From time characteristics of the difference of potentials U LN each lower branch of KZT2, or KZT4, or KZT6, valves each phase of the module 100 you can see that each of the items shown for the example of four subsystems 10 is managed so that its terminal voltage U X21 is always zero. According to 1 of these lower branches KZT2, or KZT4, or KZT6, valves three-phase 100 modules branch KZT2, gates has a defective bipolar subsystem 10, indicated by the shading. Due to this, the value of the amplitudes of the voltage U LN each branch T2, T4 and T6 valves can be at most equal to only 3·U C . Through this well-known method amount used subsystems 10 in case of failure is set equal to the number of used subsystems 10 in case of absence of fault. The characteristic amplitude of the sum of the difference of potentials U PL and U LN is shown on the diagram Fig.8 a dashed line. In relation to the case of absence of fault voltage U L10 , U L20 and U L30 in case of failure have a correspondingly lower maximum amplitude. In the example shown below, these voltage U L10 , U L20 and U L30 in case of absence of fault have a maximum amplitude of the magnitude 1/2·U d , while in case of failure of the maximum amplitude is only 3/8·U d . That is, by the known method in the event of a malfunction receive a symmetrical three-phase voltage system with a lower maximum amplitude.

Figure 9 shows the characteristics of the difference of potentials U PL and U LN according Fig.7 and 8 to the time t. From this temporal characteristics of potential output load L1 or L2, or L3 from a virtual middle point On, you can see that it deviates from zero position already asymmetrically. This zero position was shifted to 1/8·U d . This means that this characteristic potentials has a constant component.

An invention is based on objective to improve the known method of control so that the output voltages AC adapter with distributed energy storage devices in case of fault, not manifested components of the DC voltage.

This problem is solved in accordance with the invention of the distinctive features in the relationship with signs of a limited part of paragraph 1 of the claims.

Due to the fact that the branches of the gates, corresponding defective branch of the valve faulty phase module a number of bipolar subsystems, and this number corresponds to the number of faulty subsystems controlled in such a way that the amplitude of terminal stresses are equal to zero, the output voltage of the faulty phase module no longer contains the constant component. In view of the symmetry conditions, the appropriate subsystems in the branches of gates serviceable phase modules are managed appropriately. Get free from the constant voltage symmetrical three-phase voltage system.

For further explanation of the invention refers to drawings which shows a schematic form of the relevant invention of ways to control multi-phase rectifier AC with distributed energy storage devices.

Figure 1 shows an equivalent circuit of the famous AC adapter with distributed energy storage devices;

figure 10-12 - represent characteristics of the potential phase rectifier system AC power on figure 1, in case of malfunction, respectively, in the diagram to the time t, which are generated by the corresponding invention of ways.

Suppose that a bipolar subsystem 10 branches T2 valves phase module 100 AC adapter with distributed drives 9 of energy according to figure 1 due to some fault is securely short. This faulty bipolar subsystem 10 below presents the equivalent circuit according to figures 1 through the hatch.

According to the relevant invention of the method, at first this faulty bipolar subsystem 10 should be determined. After this faulty bipolar subsystem 10 defined, this subsystem 10 controlled in such a way that the amplitude of the corresponding terminal voltage U X21 equal to zero. This phase module 100, in which branch of KZT2, gates has a defective subsystem 10, hereafter referred to as faulty phase module 100. This faulty phase module 100 has, in addition, the branch T1 gates, in which no subsystem 10 is not faulty. According to the mode corresponding to the invention, according to the number of faulty bipolar subsystems 10 in the affected branches T2 gates, corresponding number of bipolar subsystems 10 working branches T1 gates of this faulty phase module 100 is managed so that, accordingly, the amplitude of the terminal voltage U X21 equal to zero. In this example, because only one bipolar subsystem 10 branches T2 faulty valves in the corresponding branch of the T1 gates only one bipolar subsystem 10 controlled in such a way that the amplitude of its terminal voltage U X21 equal to zero.

10 on the chart on time t shows the time response of the difference of potentials U PL terminals R relative to output load L1. On 11 in the diagram to the time t shows the time characteristics of a potential difference LN U terminals L on the capacities of terminals N. From both the characteristics of potentials U PL and U LN can be seen that, of the four bipolar subsystems 10 branches T1 and T2 valves to control the order given only three subsystems 10. The sum of these two characteristics of potentials U PL and U LN newly independent constant voltage U d that exists between the teams tires P 0 and N 0 a constant voltage of this AC adapter with distributed drives 9 energy according to the figure 1. This means that the constant voltage U d in case of absence of fault in case of a failure equally. Based on the symmetry of bipolar subsystem 10 branches T4, T3, T6, T5 valves both serviceable phase modules 100 AC adapter with distributed drives 9 energy according to the figure 1 are managed appropriately. This means that the relevant faulty branches T2 valves faulty phase module 100 surviving branches of T4 and T6 valves serviceable phase modules 100 AC adapter on figure 1, a number of subsystems 10, corresponding to the number of faulty subsystems 10, controlled in such a way that the amplitude of terminal voltage U X21 respectively equal to zero. As in the faulty branches T2 valves faulty phase module 100 faulty only one subsystem 10, the relevant branches of KZT2, valves branches of T4 and T6 valves serviceable phase modules 100 AC adapter with distributed drives 9 energy of figure 1, respectively, only one bipolar subsystem 10 controlled in such a way that the amplitude of the corresponding terminal voltage U X21 are equal to zero. In a failed phase module 100 in a healthy branch T1 gates also one subsystem 10 controlled in such a way that the amplitude of the corresponding terminal voltage U X21 equal to zero. This means that in healthy phase modules 100 AC adapter with distributed drives 9 energy on figure 1, in the relevant working branches T1 valves faulty phase module 100 branches T3 and T5 valves serviceable phase modules 100 appropriate subsystems 10 in the number of faulty subsystems 10 faulty branches T2 valves are managed in such a way that the amplitude of their terminal voltage U X21 also zero.

Due to this control subsystems 10 AC adapter with distributed drives 9 energy get output voltage U L10 , U L20 and U L30 , which, respectively, are applied between the output L1, L2 and L3 AC voltage and virtual mid-point O. this weekend voltage U L10 , U L20 and U L30 have the feature of potential U LO , which is presented in the diagram to the time t at fig.12. This feature no longer has a constant component. The amplitude of these output voltages U L10 , U L20 and U L30 , respectively, less amplitudes of the output voltages generated by the known method of management. According to the example with four subsystems 10 to branch T1, ..., T6 valves output voltage U L10 , U L20 have, respectively, the amplitude 1/4·U d compared to the amplitude 3/8·U d (known way to control). However, this symmetrical three-phase voltage system with smaller amplitude is free from the constant voltage.

The constant component, which in a way is manifested in the output voltages U L10 , U L20 and U L30 AC adapter with distributed drives 9 energy of figure 1, stipulates in a connected machine with a rotating magnetic field shift neutral, which can lead to the currents in the bearings. In addition, the named constant component, when using an AC drive as active, direct mains supply, causes a shift in the capacity of an AC drive compared to ground potential, if neutral network moans grounded. This requires, in the circumstances, more cost isolation AC inverter. , In a manner appropriate to the invention, this lack is eliminated, but should take into account the lower amplitudes of the output voltages U L10 , U L20 and U L30 AC adapter on figure 1. More than bipolar subsystems 10 applies in the branches T1, ..., T6 gates, the more the number of steps will be output voltage U L10 , U L20 and U L30 AC adapter with distributed drives 9 energy of figure 1. Thus, it can be approximated sine characteristic even with faulty bipolar subsystems 10.

Way to control rectifier AC with at least two phase modules (100), with upper and lower branch (T1,..., T6) valves, contains respectively at least three electrically linking of the two-pole subsystem (10)in case of failure of at least one subsystem (10) branches (T1,..., T6) of the valve and is determined by the branch (T1,..., T6) valves with a faulty subsystem (10), respectively subsystem (10) branches (T1,..., T6) valves, with a faulty branch (T1,..., T6) gates, each of correct phase module (100) controlled in such a way that its terminal voltage (U X21 ) respectively equal to zero, wherein the subsystem (10) branches (T1,..., T6) valves, with a faulty branch (T1,..., T6) valves, faulty phase module (100) controlled in such a way that its terminal voltage (U X21 ) is equal to zero, and that accordingly subsystem (10) branches (T1,..., T6) valves, with this branch (T1,..., T6) gates, each of correct phase module (100) controlled in such a way that its terminal voltage (U X21 ) is equal to zero.