FR2941301A1 - METHOD AND DEVICE FOR HIGH ENERGY EFFICIENCY CHARGING TESTING OF EQUIPMENT - Google Patents

Abstract

The method according to the invention is intended to carry out a charging test, with high energy efficiency, of an electrical, electronic or electromechanical (IT) equipment. It consists in replacing the dynamic load (1) of this equipment (IT) with a simulated load (BS) consisting of an electronic system behaving like the load (1) with respect to the equipment (IT). At least a fraction of the electrical energy received by the electronic system (BS) is injected, after having undergone an appropriate conversion to its regeneration, on a transmission and distribution network of electrical energy (TR).

Description

The present invention relates to a method and a device for the charging test, with high energy efficiency, of an electrical, electronic or electromechanical equipment, with simulation of the dynamic load of this equipment by an electronic system having, seen from equipment, the same characteristics including electrokinetic or electromechanical 15 that the actual load.

It also relates to the electronic simulation and energy transfer system implemented by said method.

The invention is not limited to a particular type of equipment to be tested: this equipment may, for example, consist of electronic or electromechanical systems on board a vehicle (civil or military) such as, for example, an aircraft.

It is known, in particular, that in the aeronautical field, there has been a technological evolution of actuators for several decades, in particular engines and cylinders, from hydraulics to electrohydraulics, or even pure electric power. This evolution has therefore made it necessary to design and manufacture new test means (test benches) capable of testing the control and / or power components of these actuators.

However, under load, the powers absorbed by these actuators are relatively large, for example 30 to 50 KW AC or 30 KW DC.

Usually, the power absorbed by the simulation devices used in place of these actuators is determined from a specific absorption law of the actuator considered.

The energy absorbed by these simulation devices is not used to generate an action, for example mechanical, similar to that of the actuator that it is supposed to simulate, but is usually dissipated by Joule effect.

The heat produced by this dissipation must then be evacuated by means of cooling integrated in the simulation device.

It thus appears that in addition to their relatively high energy consumption, these simulation devices have the disadvantage of requiring the use of heavy cooling devices, bulky and relatively expensive.

The object of the invention is therefore more particularly to eliminate these disadvantages.

It therefore proposes, for this purpose, a method for the test in charge of an equipment, this method comprising the replacement of the load by a simulated load consisting of an electronic system behaving as the load with respect to said equipment, and the controlled supply of the electronic system by said equipment as if it were the load.

According to the invention, this method is characterized in that at least a fraction of the electrical energy received by the electronic system is injected into a transmission and distribution network of electrical energy that may notably consist of the power supply network. equipment to test. after undergoing an appropriate conversion to its regeneration on said network.

Advantageously, the method according to the invention may comprise a step of continuous / alternating conversion of the voltage delivered by the equipment to be able to inject the electrical energy received on a transmission and distribution network of electric current, this conversion step being performed after adaptation of said voltage to said converter used to perform the conversion. This adaptation can be achieved by a voltage-boosting chopper whose absorbed current is slaved to the voltage Vi. from the equipment to be tested, with a current setpoint determined according to said voltage, by a voltage / current control law established according to a model of the simulated load.

The converter used may comprise a booster type (or "Boost") continuous / continuous slaved according to said control law, this chopper being followed by a conversion stage for transforming the direct current delivered by the chopper into a current suitable for the network on which the injection of electrical energy is to be made.

The chopper may be in the form of a quadrupole with two input terminals and two output terminals and comprise: a first circuit connecting a first chopper input terminal to a first output terminal, this first circuit comprising in series an inductance and a diode mounted directly, a second circuit connecting the second input terminal to the second output terminal, this second circuit being connected to the first by a controllable switch connected to the link between the inductor and the diode and an assembly comprising, connected in parallel between the two output terminals 5 of the chopper, a capacitor and a resistive load.

The operation of this chopper may comprise a succession of cycles comprising the following phases:

A phase of magnetic energy accumulation which is obtained when the switch is in the closed state (on state): the increase of the current in the inductance generates the storage of a quantity of energy in the form of of magnetic energy. The diode is then blocked so that the circuit downstream of the diode is disconnected from the power supply. A charge phase of the capacitor which is obtained during the opening of the switch: the inductance is then in series with the equipment and its electromotive force is added to the voltage applied to the input of the chopper by the equipment to be tested. The current flowing through the inductor then flows through the diode, the capacitor and the load. This results in a transfer of the energy accumulated in the inductor to the capacitance.

The output voltage (continuous) of the chopper is applied to the input of a regeneration circuit comprising a return inverter on the network which triggers on a voltage threshold: as soon as the output voltage of the chopper exceeds this threshold, the inverter returns the energy stored by the capacitor on the network. Thus, the inverter is capable of converting the output voltage of the chopper / hoist into a single or multiphase alternating voltage.

Of course, in the case where the equipment to be tested behaves with respect to the load as an alternating voltage generator, the chopper will have to be preceded by a voltage rectifier stage.

One embodiment of an electronic simulation system that can be used in accordance with the method according to the invention will be described below, by way of nonlimiting example, with reference to the appended drawings in which: FIG. 1 is a block diagram of the electronic simulation system;

Fig. 2 is a diagram illustrating the principle of controlling the chopper controllable switch shown in Fig. 1;

Figure 3 is a diagram of the safety circuit provided at the output of the chopper.

As illustrated in FIG. 1, the electronic simulation system used for carrying out the method according to the invention comprises:

a simulation circuit BS comprising two input terminals E1, E2 intended to connect to terminals BI, B, connecting the load 1 (shown in broken lines) of the equipment to be tested, replacing this charge, and two output terminals Si, S2 delivering a direct voltage Vo, and a regeneration circuit BR which receives on its two inputs E3, E4 the voltage delivered by the simulation circuit BS and a three-phase output 25 (terminals S3, S4 , S5) intended to be connected to a three-phase network TR for example 400 V.

In this example, the simulation circuit BS comprises a step-up chopper (block 2), of the "Boost chopper" type, controlled by a control circuit including a processor P according to a specific control law LC 2941301 -6- load 1 that we want to simulate. This chopper 2 is secured by a safety circuit CS.

The regeneration circuit BR comprises an inverter O for converting the output DC voltage Vo of the step-up chopper 2 into a three-phase AC voltage of 400V.

The choice of a voltage step-up chopper 2 is motivated for the following reasons: It allows, under the control of the processor P, to control the current delivered by the installation, according to the LC control law, and thus to simulate the load 1 (for example a resistive load). It makes it possible to obtain an output voltage Vo appropriate to the operation of the inverter O of the regeneration circuit BR and thus provides a function for adapting the signal between the output of the installation under test IT and the input of the inverter O.

In the case where the test installation IT delivers a DC voltage on its output terminals B 1, B2 (and behaves as a DC voltage source SC, shown symbolically in FIG. 1), the elevator chopper 2 can connect directly on terminals B ,, B2, or via a voltage adapter (indicated by a voltage divider bridge DV in Figure 1).

On the other hand, in the case where this voltage is alternative, it will be necessary to include a voltage rectifier stage upstream of the chopper 2.

In the example illustrated in FIG. 1, the elevator chopper 2 has been shown schematically in the form of a quadripole in which: The input terminal E1 is connected to the output terminal S1 via a circuit comprising an inductor L and a diode D mounted in forward direction.

The input terminal E2 is connected to the output terminal S2 via an equipotential conductor T (ground). This conductor T is connected to the connection between the inductor L and the diode D by a controllable switch SW1 and to the connection between the diode D and the output terminal S1 by an assembly comprising in parallel a capacitor C 1 and a resistor R1 .

The operating cycle of the chopper 2 previously described comprises two distinct phases according to the state of the switch SW1, namely:

A phase of accumulation of energy: when the switch SW1 is closed (on state), the increase of the current in the inductance L generates the storage of a quantity of energy in the form of magnetic energy. The diode D is then blocked and the circuit located downstream of the diode D is then disconnected from the circuit SC-L-SW1.

A phase of energy transfer which takes place when the switch SW1 is open; the inductance L is then in series with the source SC and its electromotive force (f.e.m) is added to that of the source SC (booster effect). The voltage across the inductance L is expressed as follows: VL = LdIL / dt IL being the current flowing in the inductor L The variation in time dt is none other than the switching time of the switch SW1 and diode D; he is so tiny. A large voltage therefore appears across the inductance L. The current flowing through the inductor L then passes through the diode D, the capacitor C1 and the resistor R1. This results in a transfer of the energy accumulated in the inductor L to the capacitor C1 which is therefore brought to a voltage Vo much higher than that of the voltage Vi delivered by the voltage source SC. In the example illustrated in FIG. 2, the command of the controllable switch SW1 is ensured by a servocontrol circuit, using a control law LC, from which a setpoint signal le which is applied on the input is developed. positive of a subtracter So which receives on its negative input a signal representative of the current IL crossing the inductance L and which is provided by a data acquisition block BA of the chopper 2. This acquisition block BA delivers in particular data voltage (in particular of the voltage Vi 'at the chopper input 2), current data (in particular the current IL flowing in the inductor L) and temperature data T ° I. T ° 2, T ° 3 at various points of chopper 2.

This acquisition block BA transmits in particular a datum representative of the voltage Vi 'to the control law which produces a corresponding reference signal, for example of the type where the = Vi' R 'being proportional to the resistance of the load 1.

The output of the subtracter So is connected to a corrector Co connected to the input of a controllable switch SW2, controlled by a safety circuit CS which receives the temperature data T ° 1, T ° 2, T ° 3 and produces a control signal of the switch SW2 according to these data.

The switch SW2 is connected by its output to the control input of a pulse width modulated signal generator GS.

The purpose of the safety circuit previously described is to block the control of the chopper 2 in case of overheating of the system. For this purpose, the sensors that measure the temperatures T ° 1, T ° 2, T ° 3 are placed in different locations of the chopper, in particular at the switch SW1 and the diode D, so that to monitor their evolution. The values are read by the BA acquisition block and processed by an operating system. If one of the temperatures T ° 1, T ° 2, T ° 3 is considered dangerous because it is too high, then the generator 5 GS transmits, to the control switch SW1 of the chopper 2, a provoking control signal his blockage.

Furthermore, a safety device placed at the output of the chopper 2 can be provided to lower the output voltage of the chopper 2 if an overvoltage 10 occurs. Its purpose is to discharge the capacitor IC before it reaches a predetermined maximum voltage.

As illustrated in FIG. 1, this safety device may comprise a safety control device 5 comprising a voltage divider bridge 15 provided with a hysteresis comparator which measures the output voltage Vo of the chopper 2. The comparator assures the control of a controllable switch SW3, for example of the IGTB type, for discharging the capacitor CI through a discharge resistor R2 when the output voltage VI reaches a predetermined high threshold value. By way of example, for an input voltage Vi equal to 1 10 V. the output voltage Vo of the chopper 2 will be between 575 V and 600 V. For the system to best simulate the behavior of a resistor, a tolerance of 3% has been set in relation to the rated current. The ripple of the current flowing in inductance L is 1.5A peak-to-peak, with a duty cycle of 0.83.

Since this chopper 2 is operated at voltages up to 800 V and at a frequency of a few KHz, for example 3 KHz, the choice of controllable switches SW1, SW2, SW3 has naturally focused on IGBT (Insulated Gate Bipolar Transistor) technology. With regard to the diode D used in the chopper 2, in this example, the choice fell on a FRED diode (Fast Recovery Epitaxial Diode) which makes it possible to obtain a very short recovery time and losses. weak switching. Inductance L has been chosen so that it can supply enough energy to keep the system running smoothly. In this example, it has an inductance of 21 mH with an internal resistance of 86 mS2. The capacitor used in the chopper has been determined so that it can work with a voltage of 800 V and therefore has a capacity of 831aF. The use of a set of the same capacity comprising two capacitors in series makes it possible to have a higher tension to be smoothed. The inverter 2, used in the regeneration block BR, may advantageously consist of a threshold triggering inverter O which allows reinjection on the network when a sufficient voltage is applied to its input. In the example described above, the inverter O used is an EMB 934 inverter from the company LEUZE.

This inverter O, which is a DC-AC converter makes it possible to convert the direct voltage Vo across the capacitor CI of the chopper 2 to the same voltage and at the same frequency as the three-phase output network (here 400 V - 50 25 Hz). .

In view of the fact that this inverter O supplies at its output a pulse width modulated pulse (PWM) voltage system, between each output of the inverter O and each phase Phi, Ph2, Ph3 of the TR network, a filter comprising, for example, inductance LF1, LF2, LF3. 2941301 -11- This filter converts the voltages delivered by the inverter O into almost sinusoidal currents directly applicable to the TR network.

FIG. 3 shows an embodiment of the control circuit of the controllable switch SW3 (here an IGBT transistor) provided for discharging the capacitor IC into the resistor R2.

This circuit comprises a hysteresis comparator CH having a subtractor OP operational amplifier, the negative input of which is connected to the cursor of a potentiometer Po connected between the terminals S 1 and S 2.

The positive input of this operational amplifier OP is connected to the junction of the resistors R3, R4 of a voltage divider bridge connected between the terminal S2 (ground) and a positive DC voltage source SV] (for example 5 volts) . The output of the operational amplifier OP drives the base of a transistor TI whose emitter is connected to the positive voltage source SV1 (5 V) and the collector is connected to ground via a light emitting diode DL1 driving a DC control circuit of the switch SW2 (driver IGTB), the DC control circuit being mounted between the ground and a DC source SV2 (for example 15V). The output of this DC control circuit is applied to the control terminal G2 of the controllable switch SW2 serving to discharge the capacitor C 1 through the resistor R2.

The advantage of the control circuit previously described is that when the voltage across the capacitor C rises to a first critical threshold (high threshold) the controllable switch SW2 becomes on and causes the discharge of the capacitor C 1 The voltage across the capacitor C then drops until it reaches a second threshold (low threshold) lower than the first one. In this case, the switch SW2 goes to the off state thereby interrupting the discharge of the capacitor CI. The control terminal G2 of the controllable switch is also connected to a control circuit controlled by a voltage-free detector.

This control circuit comprises a relay whose coil BO is supplied by a DC voltage source SV3 (for example 15 volts). This relay actuates two switches namely, a first switch 11 which, in the closed state, makes it possible to connect the control terminal G2 to a capacitor C2 and a second switch I2 which, when closed, makes it possible to connect the capacitor C2 to the DC voltage source SV3.

The two switches I2 have an inverted operation: in the closed state of one of the switches corresponds the open state of the other switch and vice versa. When the voltage of the source SV3 is present, the switch 11 is on and the capacitor C2 is maintained under load.

When the voltage of the source SV3 is absent (power failure), the switch I2 is on and applies the voltage of the capacitor C2 to the terminal G2.

Thus, thanks to the control circuit previously described, a discharge of the capacitor IC is obtained both in the case of an overvoltage and in the case of a power failure. 15

Claims (14)

Revendications1. A method for the energy-efficient, load-testing of electrical, electronic or electromechanical (IT) equipment, which method comprises replacing the dynamic load (1) of this equipment with a simulated load consisting of an electronic system ( BS) behaving like the load (1), vis-à-vis said equipment (IT) and the controlled supply of the electronic system (BS) by said equipment (IT) as if it were the power supply of the charge (1), characterized in that at least a fraction of the electrical energy received by the electronic system (BS) is injected, after having undergone a conversion appropriate to its regeneration, on a transmission and distribution network. electric energy (TR). 2. Method according to claim 1, characterized in that it comprises a DC / AC conversion step of the voltage delivered by the equipment (IT), after adaptation of this voltage to the converter (0) used to perform said conversion, and in that said adaptation is performed by a voltage step-up chopper (2) whose absorbed current is slaved to the voltage (Vi) coming from the equipment (IT) to be tested, with a current setpoint (Ic) determined in function of said voltage (Vi) by a voltage / intensity control law established according to a model of the simulated load (1). 3. Method according to claim 2, characterized in that the aforesaid voltage boosting chopper (2) is in the form of a quadrupole comprising: a first circuit connecting a first input (El) to a first output (S, ), said first circuit comprising in series, from the input, an inductance (L) and a diode (D) mounted directly, a second circuit connecting a second input (E2) to a second output (S2) this second circuit being connected to the first by a controllable switch (SW1) connected to the connection between the inductor (L) and the diode (D) and an assembly comprising, between the two outputs of the quadrupole, a capacitor (CI) and a load connected in parallel. 4. Method according to claim 3, characterized in that the aforesaid elevator chopper (2) performs a succession of cycles each comprising the following phases: a phase of accumulation of magnetic energy which is obtained when the switch (SW1 ) is in the closed state, the diode (D) being blocked, a charging phase of the capacitor (CI) which is obtained during the opening of the switch (SW1) and during which it is carried out a transfer of the energy accumulated in the inductor (L) to the capacitor (CI). 5. Method according to claim 2, characterized in that the DC / AC conversion step is performed by an inverter (Co) which returns the energy stored by the capacitor (CI) as soon as the output voltage of the chopper exceeds a predetermined voltage threshold. 6. Method according to one of the preceding claims, characterized in that it comprises a step of rectifying the voltage delivered by the equipment (IT) to be tested in the case where this equipment (IT) behaves vis-à-vis -vis the load as an alternating voltage generator. 7. Device for implementing the method according to one of the preceding claims, characterized in that it comprises a simulation circuit (BS) comprising a voltage step chopper controlled by a control circuit comprising a processor (P) according to a control law (LC) specific to the load that 2941301 - 15 - one wants to simulate and a regeneration circuit (BR) which transforms the voltage delivered by the simulation circuit into an alternating voltage that can be injected on a network. 5 8. Device according to claim 7, characterized in that the regeneration circuit (BR) comprises an inverter (0) adapted to convert the output DC voltage of the elevator chopper into a single or multiphase alternating voltage. 10 9. Device according to one of claims 7 and 8, characterized in that the aforesaid elevator chopper (2) comprises: an input (El) connected to an output (SI) via a circuit comprising an inductor ( L) and a diode (D) mounted in direct direction, an input (E2) connected to an output (S2) by a conductor (T) connected to the connection between the inductor (L) and the diode (D) by a controllable switch (SW1) and the connection between the diode (D) and the output (SI) by an assembly comprising in parallel a capacitor (CI) and a resistor (RI). 20 10. Device according to claim 7, characterized in that the control of the controllable switch (SW1) is provided by a servocontrol circuit using a control law (LC) from which is developed a setpoint signal which is applied to the positive input of a subtracter (So) which receives on its negative input a signal representative of the current (IL) passing through the inductor (I) and which is supplied by a data acquisition device of the chopper, and in that the output of the subtracter (So) is connected to a pulse width modulated (GS) modulated signal generator which generates a control signal of the switch (SW1). 2941301 - 16 - 11. Device according to claim 10, characterized in that the circuit providing the connection of the subtractor output to the control circuit comprises a controllable switch (SW2), controlled by a safety circuit (CS) which receives temperature data. (T ° 1, T ° 2, T ° 3) of the chopper and elaborates as a control signal of the switch (SW2) according to these data. 12. Device according to one of claims 7 to 11, characterized in that it comprises a safety device placed at the output of the chopper, so as to lower the output voltage of said chopper if an overvoltage occurs. 13. Device according to claim 12, characterized in that the aforesaid safety device comprises a voltage divider bridge 15 associated with a hysteresis comparator which measures the output voltage of the chopper and controls a controllable switch (SW3) for discharging the capacitor through a resistor (R2) when the output voltage (VI) reaches a predetermined high threshold value. 20 14. Device according to one of claims 7 to 13, characterized in that the inverter used in the regeneration block consists of a threshold-triggered inverter (0) which allows the reinjection of current on the network when a voltage sufficient is applied on its input.