JP2002533046A - Energy recovery system of electric fan for automobile radiator - Google Patents

Abstract

(57) Abstract: An energy recovery system for an electric fan for a radiator of a vehicle having at least one power supply (B) capable of starting at least one cooling fan (V). This power supply is connected to an electronic control device (CM), operated by a monitoring electronics box (CC), and coupled to an electric machine (M). The electronic control device (CM) and the electric machine (M) such that the electric machine (M) is configured as a motor for the fan or as a control generator operated by the fan itself. ), A monitoring circuit is arranged. The electric machine (M) is controlled by an application program for a computer capable of introducing the electric machine (M) into a function of a size or parameter in the system and / or a command outside the system.

Description

DETAILED DESCRIPTION OF THE INVENTION

An object of the present invention is an energy recovery system for an electric fan for a radiator of an automobile.

At present, there is a well-known tendency in the automotive industry to choose technical solutions aimed at reducing consumption.

[0003] It is an object of the present invention to generate electrical energy during periods when the electric fan itself is not in use by using an electric fan group of a radiator. On the other hand, the fan rotates with the hydrodynamic energy of the air flow introduced by the vehicle engine.

[0004] Normally, the above-mentioned energy is not used, so the fan, when not driven by an electric motor, rotates at a very high speed to reach a speed that dynamically balances the speed of the air. This situation occurs whenever the airflow generated by the vehicle's engine is sufficient to cool the radiator by itself.

It should be noted that even if the amount of recovered energy is on the order of tens of watts, these wattages must be approximately doubled in relation to the total amount of energy. Otherwise, the energy is supplied from the onboard synchronous generator with approximately 50% efficiency.

The present invention is particularly relevant and interesting when considering an electronic speed controlled electric fan. This is because the present invention can achieve the above-mentioned objects without additional practical costs. The only addition needed is to add to the machine's own control logic the management logic that allows the machine to function as a generator.

[0007] To achieve these and additional objects and advantages, which will be better understood below, the present invention provides at least one power supply (B) capable of starting at least one cooling fan (V). The present invention provides an energy recovery system for an electric fan for a radiator of an automobile, comprising: This power supply is connected to an electronic control device (CM), operated by a monitoring electronic box (CC), and coupled to an electric machine (M).
The electronic control device (CM) and the electric machine (M) such that the electric machine (M) is configured as a motor for the fan or as a controlled generator operated by the fan itself. ) Is disposed between the monitoring circuit.
The electric machine (M) is controlled by an application program for a computer capable of introducing the electric machine (M) into the size or parameters in the system and / or the function of commands outside the system.

The system according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a functional form of an electric fan group for a radiator of an automobile.

A indicates airflow, V indicates a fan, M indicates an electric machine (motor / generator), and CM indicates an electronic control unit for the latter. F shows an electrical filter placed between the CM and the battery (indicated by B) to smooth out the harmonic components of the current. CC indicates a control unit external to the motor. It sends inputs to the CM and controls the function of the fan (on, off, speed, etc.) according to variables imposed by different car manufacturers (eg, air temperature, vehicle speed, etc.).

The system configured in FIG. 1 in which the machine M is operated as a motor only by the CM is one of the well-known systems commonly used at present.

As mentioned above, in terms of cost, the invention applies only in the form of a block CM which gives a “bridge” command structure, without substantially modifying the functional blocks shown in FIG.

[0013] The present invention is particularly applicable to a variety of systems, including: a) incorporating input logic into the system to enable the conversion of an electric machine from a controlled motor to a controlled generator; b) the machine as a generator. According to the needs of the client, management software is added in the block CM that can control the generator at the required speed and limit the current to a maximum fixed level or limit according to the voltage of the battery.

[0014] Due to this deformation, a "braking phenomenon" that affects the fan rotated by the air flow.
The whole can be automatically controlled and managed to guarantee the maximum energy transfer from hydrodynamics to electricity (battery recharge).

For simplicity, reference is made to a motor that works by electronic switching. Its simplest form is a single-phase structure. This reference is made only for the explanation of the operating principle, taking into account that these types of motors are actually two-phase, three-phase or five-phase. However, the principles of operation described by the single-phase variant provide a sufficient explanation of how other multi-phase machines according to the current state of the art work.

The basic circuit usually starts with the bridge structure shown in FIG. This bridge structure provides a single-phase structure with four power switches P1, P2, P3, P4, which are fixed between the ends of the power supply lines. A filter CF is arranged between the bridge itself and the battery B. The simplest form of this filter is only one capacitor.

Within the bridge are the machine windings expressed as an equivalent network of electromotive force E, winding resistance Ra and winding inductance La.

When the machine functions as a motor, the control unit CC controlling the above-mentioned switches alternates between the two half-waves S1 and S2 of the electromotive force E (see FIG. 2A) according to known techniques. It operates by switching. In this case, since the power supply voltage is unipolar, one half-wave is in operation and only the other half-wave is in the bridge P1,
The P4 side switches alternately, or the P2 and P3 sides of the bridge switch alternately, always activating one pair in the machine.

These components, which in the embodiment being described are implemented by MOS, have in parallel parasitic components, usually diodes. In FIG. 1, each diode is shown in relation to a switch and is indicated by D1, D2, D3, D4.

When the machine is used as a generator, the switches P1 and P2 are no longer needed and are actually turned off by the control unit CC. as a result,
This circuit is as shown in FIG. That is, the structure is simplified to this kind of structure. 2
Two upper diodes D1 and D2, two switches P3 and P4, 2
There are two other diodes D3 and D4, but as can be seen, the latter two usually do not work. For this reason, they do not participate in the overall operation of the machine and can even be omitted from the drawing.

To understand what happens, for example, the half-wave S1 where the battery voltage is positive
It is then sufficient to consider that the switch P3 remains closed during the entire period when the electromotive force E is positive. During this half-period, node J is grounded (see FIGS. 2 and 3) and diode D1 is not operating, so it appears to be absent.

To further simplify the function on one half-wave (the function on the other half-wave is exactly the same in this case, it is useless to describe it) It can be further simplified. Here we can refer to the circuit shown in FIG. 4 which provides an immediate visual explanation of what happens.

The motor has an electromotive force E, an inductance La, a resistance Ra, a diode D2 (diode D1 is not shown because it is no longer used) and a closed switch P3 (which is (Shown as fully closed since it remains fully closed throughout the function).

What happens instead is that the other switch P4 operates by pulse modulation, ie opens and closes according to a predetermined duty cycle. The diode D2 acts first on the capacitor CF, which in turn acts on the battery B.

What actually happens during this pulse modulation?

The point of this question is that if the general electromotive force E of the machine is lower than the battery voltage,
That is how the battery B is actually charged. For example, assume that at the speed that the fan is rotating, the voltage generated inside the electric machine is 3 volts below the voltage of the battery.

When this voltage is three times lower, if switch P4 is closed, that voltage will cause a current to flow into motor inductance La and resistor Ra, and this current will be pulsed at this current level. To charge the inductance with a predetermined amount of energy corresponding to. FIGS. 5 and 5a show the shape of the current I by changing the charge CB of the battery B during the ON period T1 and the OFF period T2, respectively.

When the switch P4 is opened, the current storing energy equivalent to １ ／ Lai ² in the machine inductance La attempts to flow and continues to maintain.

When switch P4 is opened during the off period, the current from the circuit of the switch is set to zero (since it can no longer cycle through this circuit).
However, it continues to flow during the off phase of the circuit with respect to the battery.

During the period when P4 is off, the current reaching this level appears sharply through diode D2 and then into the battery circuit according to the well-known boost function diagram.

This inductance obviously seeks to reduce the current going to the battery over a period of time, but at some point switch P4 closes again and the current in the battery is reset to zero. And from this point, the current reappears in the circuit and continues to recharge it.

What happens next is that, despite the fact that there is a voltage at the start of the generator, a predetermined average current “flattened” by the capacitor of the filter CF is supplied to the battery B. is there. Starting from a lossy state in the circuit, in principle, the product EI at the input, ie the quadrupled average of the current circulating in the generator at 4 volts, is the average of the current supplied by the battery. And the value of the battery voltage.

To enable this transfer current to reach a maximum level, a shunt resistor Rs (current sensor) is provided on the return path of the battery towards the control system, from which the value of the current is taken and averaged. It is integrated through the RC circuit to give the value IB.
In practice, an average of the current in the battery is obtained and this average is given to the microswitch. This microswitch calculates the average value of the current that charges the battery,
Calculate momentarily as a function of fan conditions.

FIG. 4 shows purely by way of example an RC-type electric circuit R1, for obtaining an average value IB.
C1 is shown. Through this circuit the value of the current is time integrated and the value is transferred as input to the electronic control device CM.

At the end of the first half-wave, a Hall-effect sensor or other type of Rs sensor that can send a signal to the machine that the other half-wave is starting will move function to the other half of the machine. That is, in the other half-wave, the one that remains closed is P4 and the PWM
The one that functions with is P3. D2 does not work at all, but instead D1 becomes active in the circuit.

As can be seen from this embodiment, the bridge structure is quite basic, so that the machine effectively functions both as a generator and as a motor using the same components.

In fact, thanks to this structure, no additional power components are added and nothing else is done except to change the monitoring logic of the electronic switch. Therefore, the different software management is to switch the machine so that it monitors and limits either the speed or the current value of the machine, i.e. applies the logic that makes the machine function as a generator. Anything that can perform the management of the above is sufficient.

Instead of being of a single-phase type, the machine may have a two-phase bridge structure, a three-phase bridge structure, or a five-phase bridge structure.

In the case of a permanent magnet electronically controlled DC brush motor (not a brushless motor treated so far), an AC F.C. E. FIG. The same idea as for a single-phase brushless structure of a simplified circuit, requiring only a half-bridge structure without M, can be used (see FIG. 6).

In this case, when the machine is functioning as a motor, P1 is pulse-controlled,
P2 is off. When the machine is functioning as a generator, P1 is turned off and P2 is pulse-controlled.

In both cases, the loss of voltage on Rf sends information about the current in the motor to the motor control CM for the same reasons as described above.

In conclusion, the functions of the diodes (D1, D2) can be performed by the same switches (P1, P2) that are set to the on position within a time when they are expected to act as conductors for the diodes. Should be explained.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electric fan group for an automobile.

2 to 6 are diagrams of a wiring diagram and a system according to the present invention applied to an electric fan group for an automobile.

──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D037 CA04 CB34 3D038 AA05 AB01 AC14 5G003 AA07 BA01 CC02 DA07 GB06 5H590 AA02 CA14 CC02 CC22 CC23 CC24 CE05 FB01 FB03 FC12 FC17 FC22 FC26 GA10 GB05 HA02 HA04 JA02 JA13 JA19 JB15

Claims (13)

[Claims] 1. A monitoring electronic box (CC) connected to an electronic control device (CM).
A radiator electric fan energy recovery system comprising at least one power supply (B) coupled to the electric machine (M) and capable of starting at least one cooling fan (V) by the electric machine (M). The electronic control device (CM) and the electric machine (M) such that (M) is configured as a motor for the fan or as a controlled generator operated by the fan itself.
A monitoring circuit is arranged between the electronic machine (M) and a computer capable of introducing the electric machine (M) into a function of a size or a parameter in the system and / or a command outside the system. An energy recovery system controlled by an application program. 2. The monitoring circuit according to claim 1, wherein the monitoring circuit includes at least two electronic power switches (P3).
, P4) and at least two diodes (D1, D2) in a bridge or half-bridge configuration, wherein the switches (P3, P4) and the diodes (D1, D2) are connected to the electrical machine (M). 2. The energy recovery system according to claim 1, wherein the energy recovery system is electrically connected to the windings (E, Ra, La). 3. The function of said diodes (D1, D2) can be realized by the same switches (P1, P2) maintained in the on position during the delay time, said diodes functioning as conductors. The energy recovery system according to claim 2, wherein the energy recovery is performed. 4. The power source (B) is a storage battery, to which at least one
The energy recovery system according to claim 2, wherein the two filters (CF) are electrically connected in parallel. 5. The energy recovery system according to claim 4, wherein the filter (CF) is defined by one capacitor. 6. A first electronic power switch (P1, P2) during a first functional condition.
3) is closed, and the second electronic power switches (P2, P4) function with pulse modulation, the windings (E, Ra, La) being connected to a single electronic parasitic component (D2). The energy recovery system according to claim 2, wherein: 7. A current sensor device (Rs, Rf) in series with an impedance defined by a parallel connection of the filter (CF) and the power supply (B).
The energy recovery system according to claims 4 and 6, characterized in that the sensor device (Rs, Rf) obtains the value of the circulating current during the time. 8. The current value is integrated during the time by an RC type electric circuit (R1, C1) to obtain an average value (IB), and the average value (IB) is
The energy recovery system according to claim 7, characterized in that it is transferred as input to the electronic control device (CM). 9. The first electronic power switch (P1) during a second functional condition.
, P3) function with pulse modulation, and said second electronic power switch (P2, P4).
3), wherein said windings (E, Ra, La) are connected to a single electron parasitic component (D1). 10. The electric machine (M) according to claim 1, wherein the first and second functional conditions include:
Energy recovery according to claim 2, characterized in that the condition relates to an associated positive and / or negative half-wave of the electromotive force signal (E) of the first embodiment, the condition being indicated by an electronic sensor, for example a Hall effect sensor. system. 11. The machine according to claim 1, wherein the electric machine is a single-phase electronic switching machine, a two-phase bridge machine, a three-phase bridge machine, or a five-phase bridge machine. Energy recovery system. 12. The energy recovery system according to claim 1, wherein the electric machine (M) is defined by a single-phase brushless motor. 13. The energy recovery system according to claim 1, wherein the electric machine (M) is defined by a DC brush motor having an electrically controlled permanent magnet.