WO2008068541A1

WO2008068541A1 - Method and control unit for equipment using electrical energy

Info

Publication number: WO2008068541A1
Application number: PCT/HU2007/000117
Authority: WO
Inventors: László GLOCZ
Original assignee: Glocz Laszlo
Priority date: 2006-12-07
Filing date: 2007-12-05
Publication date: 2008-06-12
Also published as: HU226986B1; HUP0600901A2; HU0600901D0

Abstract

Method for controlling an apparatus (37) operated with electric energy, e.g. electric motor (1). The energy source is a direct-current storage means (2) which is connected to the apparatus (37) through a control unit (3) and a converter circuit connected to the same. The control unit (3) comprises a first control circuit (5) and a second control circuit (6) both provided with temporary energy storage means (7) and having the same structure but operated in push-pull manner so that in a first state of the clock signal the temporary energy storage means (7) in the first control circuit (5) are recharged while the voltage of the previously recharged temporary energy storage means (7) in the second control circuit (6) is transmitted to the motor (1). In a second state of the clock signal the control circuits (5,6) are controlled inversely.

Description

METHOD AND CONTROL UNIT FOR EQUIPMENT USING ELECTRICAL ENERGY

The invention relates to a method for controlling an apparatus operated with electric energy, for example an electric motor wherein the energy source is provided by a direct-current storage means preferably comprising at least two batteries, the storage means is connected to the motor through a control unit and a converter circuit connected to the same. The invention also relates to an electric apparatus for controlling the motor, for example an electric motor of a vehicle provided with at least one control element, namely a deceleration sensor and/or an acceleration sensor, preferably a brake means and/or an accelerator means, wherein the energy source is provided by a direct-current storage means preferably comprising at least two batteries, during acceleration the motor is operated in motor mode of operation and during deceleration it is operated in generator mode of operation, and the storage means is connected to the motor through a control unit and a converter circuit connected to the same. Further, the invention relates to a control unit for controlling an electric apparatus, for example an electric motor of a vehicle provided with at least one control element, namely a deceleration sensor and/or an acceleration sensor, preferably brake means and/or accelerator means, wherein the deceleration sensor of the vehicle has outputs for transmitting the signals of the brake means when sensing the operation of the brake means and a brake signal which is proportional to the extent of movement of the brake means, and the acceleration sensor of the vehicle has outputs for transmitting the signals of the accelerator means when sensing the operation of the accelerator means and an acceleration signal which is proportional to the extent of movement of the accelerator means, the energy source of the vehicle is provided by a direct-current storage means comprising at least two storage units preferably batteries, the motor is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration, and the storage means is connected to the motor through a control unit and a converter circuit which is connected to the same.

Controlled electric motors are widely used in vehicles. Basically, the present invention is intended for use in vehicle driving, but it can be used for driving electric motors, too. Electric motors for driving vehicles, known brake systems and circuit arrangements of electric motors operated by high-frequency alternating voltage can be learnt from the book titled "Jarmϋvillamossag" (Vehicle electrics) by Istvan Schmidt, lmre Rajk and Gyulane Vincze, Budapest, Technical University Press 2002.

In these days vehicle manufacturers are developing environment friendly hybrid and entirely electric vehicles. The object of the present invention is to make operation of these vehicles more economical. Recently, economic operation of electrically driven machines can be ensured by AM motors controlled by an inverter circuit operated with high-frequency alternating voltage. The circuit generating the high-frequency voltage comprises a single-phase inverter circuit and a transformer (the general frequency is 20-25 kHz). Commonly, the inverter is a resonant inverter with a 4/4 oscillating circuit. An inverter provided with dual switching element is connected to the alternating voltage mains. The two semiconductors of the dual switching element are controlled simultaneously, so that current flow in both directions is ensured. Depending on the sign of the mains voltage the inverter controller determines whether the semiconductor of the lower bridge branch or the semiconductor of the upper bridge branch is to be controlled. The instant of switching is synchronized to the zero transition of the mains voltage. The revolution number of the motor is controlled by pulse-width modulation.

Commonly, during deceleration and acceleration ultra-capacity is applied in the individual control circuits. In case of parallel brake systems the ultra-capacity is parallel connected to the main energy source, i.e. to the battery of the vehicle through a DC/DC electronic converter adapted for bidirectional flow of energy. With a converter provided with current control the flow of energy can be directed and the current jerks can be led to the ultra-capacity. By means of the DC/DC converter the charging current, the discharge current and the voltage of the ultra- capacity can be controlled. The voltage of the ultra-capacity may be higher or lower than the voltage of the battery. In case of serial application the ultra-capacity unit and the battery are serial connected. In operation - in case of even speed - the switch is in a first position. The DC/DC converter is connected to the mains voltage through a small temporary diode and causes a short-circuit in the ultra-capacity. The DC/DC converter is also adapted to continuously decrease or increase the output voltage relative to the input voltage. Therefore a vehicle driving requiring a direct voltage supply with varying intensity can also be connected to the output. This is applied for example when wheel-hub motors without commutator are used. In deceleration mode of operation the switch is turned to a second position, the voltage of the ultra-capacity is recharged in a controlled manner by means of the DC/DC converter. The energy stored in the ultra-capacity can be used during the transient time of the acceleration phase subsequent to deceleration. During this time the switch is left in its second position. As soon as the ultra-capacity is discharged, the switch is turned to the first position and the diode again causes a short-circuit in the ultra-capacity.

The same DC/DC converter may be applied both in the parallel and serial systems, but with a different purpose. In case of the parallel system the ultra- capacity is connected to the output of the converter and the converter is used for controlling the voltage and the charge of the ultra-capacity. In case of the serial connection the drive of the vehicle is connected to the output of the converter and the converter controls the voltage and current of the driving. A DC/DC converter suitable for controlling the bidirectional energy flow can be for example a buck- boost connection. Neither of these solutions can provide for the improved efficiency that is attainable with the present invention.

As opposed to the known single-way voltage multiplying rectifier the control unit of the present invention is not controlled by an intermediate oscillating circuit. It is entirely symmetric, operates in both directions and its energy storing capacity is independent of the voltage type (AC or DC) of the energy source. The object of the present invention is to provide a more dynamic, economical and energy-saving electric motor driving which is adapted to regain the motional energy in the form of electric energy in the deceleration mode of operation.

It has been realized that if an electric motor is controlled by a control unit comprising two control circuits both having the same structure, namely a first control circuit and a second control circuit which operate in push-pull manner, and the control circuits are provided with temporary energy storage means, further, if the first control circuit and the second control circuit are controlled in push-pull manner by a clock signal generated by a clock signal generator the above object can be achieved. It has also been realized that if the energy stored in the temporary energy storage means of one of the control circuits is transmitted to the motor in the acceleration mode of operation so that the voltage is increased and the current is decreased, the other control circuit recharges its own temporary energy storage means from the storage means, and in deceleration mode of operation one of the control circuits recharges its own temporary energy storage means from the motor operating as a generator, and the other control circuit transmits the energy stored in its recharged temporary energy storage means to the storage means.

Accordingly, in a first aspect there is provided a method for controlling an apparatus operated with electric energy, for example an electric motor, wherein the energy source is provided by a direct-current storage means comprising at least two storage units preferably batteries, the storage means is connected to the apparatus through a control unit and a converter circuit which is connected to the control unit. The control unit comprises two circuits, a first control circuit and a second control circuit both having the same structure but operating in push-pull manner, and the control circuits are provided with temporary energy storage means. The first control circuit and the second control circuit are controlled in push-pull manner by a clock signal generated by a clock signal generator. During the method in a first state of the clock signal the temporary energy storage means of the first control circuit or part of them are connected to each other parallel and the temporary energy storage means are connected to the storage means thereby recharging the temporary energy storage means to a voltage level close to the voltage level of the storage means. Meanwhile the temporary energy storage means of the second control circuit or part of them are connected to each other serially and the so produced direct voltage which is many times higher than the voltage of the storage means is transmitted to the converter circuit then the continuous/intermittent direct voltage appearing at the output of the converter circuit is transmitted to the motor.

In a second state of the clock signal the temporary energy storage means of the first control circuit or part of them are connected to each other serially and the so produced direct voltage which is many times higher than the voltage of the storage means is transmitted to the converter circuit. The intermittent direct voltage appearing at the output of the converter circuit is connected to the motor. Meanwhile the temporary energy storage means in the second control circuit or part of them are connected to each other parallel which are then connected to the storage means.

In a second aspect there is provided a method for controlling an electric apparatus for example an electric motor of a vehicle provided with at least one control element, namely a deceleration sensor and/or an acceleration sensor, preferably a brake means and/or an accelerator means. The energy source of the electric apparatus is provided by a direct-current storage means comprising at least two storage units preferably batteries. The motor is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration. The storage means is connected to the motor through a control unit and a converter circuit which is connected to the control unit. The control unit is formed from two control circuits with the same structure, namely a first control circuit and a second control circuit which operate in push-pull manner, and the control circuits are provided with temporary energy storage means. The first control circuit and the second control circuit are push-pull controlled by a clock signal generated by a clock signal generator in such a manner that in the normal state of the deceleration sensor and/or when the acceleration sensor is operated i.e. in the acceleration mode of operation: - In a first state of the clock signal the temporary energy storage means of the first control circuit or part of them are connected to each other parallel, the storage units in the storage means are connected serially or serially and parallel and the temporary storage means are connected to the storage means. In this manner the temporary energy storage means are recharged to a voltage level close to the voltage level of the storage means. Meanwhile the temporary energy storage means of the second control circuit or part of them are connected to each other serially. The so produced direct voltage which is many times higher than the voltage of the storage means is transmitted to the converter circuit. The continuous/intermittent direct voltage appearing at the output of the converter circuit is transmitted to the motor.

- In a second state of the clock signal the temporary energy storage means of the first control circuit or part of them are connected to each other serially. The so produced direct voltage which is many times higher than the voltage of the storage means is transmitted to the converter circuit. The intermittent direct voltage appearing at the output of the converter circuit is connected to the motor, while the temporary energy storage means in the second control circuit or part of them are connected to each other parallel which are then connected to the serially or serially and parallel connected storage units of the storage means.

When the deceleration sensor is operated i.e. in deceleration mode of operation: - In a first state of the clock signal the temporary energy storage means of the first control circuit or part of them are connected to each other serially and the temporary storage means are recharged from the motor operating as a generator to the direct voltage appearing at the control unit side output of the converter circuit. In the meanwhile the temporary storage means in the second control circuit or part of them and the parallel or parallel and serially connected storage units of the storage means are connected parallel, and the energy stored in the temporary storage means is transmitted to the storage means. - In a second state of the clock signal the temporary storage means of the first control circuit or part of them and the parallel or parallel and serially connected storage units of the storage means are connected parallel. The energy stored in the temporary energy storage means is transmitted to the storage means. Meanwhile the temporary energy storage means of the second control circuit or part of them are connected serially and the voltage appearing at the outputs of the motor operating as a generator is connected to the temporary energy storage means through the converter circuit. The intermittent direct voltage appearing at the output of the converter circuit is charged into the temporary energy storage means. Advantageously, the energy source is formed from at least three storage units the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries, the storage units are connected to each other serially in the drive mode of operation, and parallel or parallel and serially in the deceleration mode of operation by means of power supply switching elements. Preferably, the temporary storage means are high capacity condensers

(ultra-capacity) or short-time working accumulators.

The motor may be an electric motor of any type, for example a brush less DC motor, brush less AM motor or a double-commutator AC motor with brush. The generator may be an electric motor of any type which can be operated as a generator, for example a brush less DC motor or a cage motor.

Preferably, the clock signal of the clock signal generator is set to a value between 0.05 and 20 Hz. Advantageously, the frequency of the clock signal generator in the deceleration mode of operation and in the acceleration mode of operation is different. For example, on activation i.e. in cold-start mode of operation, when the motor is switched to the power supply, the ultra-capacity system is utilized primarily as temporary energy storage means so that the energy is charged into the parallel connected temporary energy storage means at least for a period of time which equals to the total working period of the serially connected temporary storage means.

Advantageously, in deceleration mode of operation detection of the signal of the acceleration means is disabled.

Preferably, the converter circuit is a known motor control circuit of a brush less DC motor.

The current from the storage means is charged into the temporary energy storage means of the control circuits through a known current-limiting circuit. Further, when the deceleration sensor is operated the current of the temporary energy storage means is led into the parallel or parallel and serially connected storage means through a known current-limiting circuit and a known DC-DC converter, e.g. buck-boost circuit connected serially to the current-limiting circuit.

In a third aspect there is provided a control unit for controlling an electric apparatus for example an electric motor of a vehicle provided with at least one control element, namely a deceleration sensor and/or an acceleration sensor, preferably a brake means and/or an accelerator means. The deceleration sensor of the vehicle has outputs for transmitting the signals of the brake means when sensing the operation of the brake means and a brake signal which is proportional to the extent of movement of the brake means, and the acceleration sensor of the vehicle has outputs for transmitting the signals of the accelerator means when sensing the operation of the accelerator means and an acceleration signal which is proportional to the extent of movement of the accelerator means. The energy source of the vehicle is provided by a direct-current storage means comprising at least two storage units preferably batteries. The motor is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration. The storage means is connected to the motor through a control unit and a converter circuit which is connected to the control unit. The control unit is formed from two control circuits with the same structure, namely a first control circuit and a second control circuit which operate in push-pull manner, and the control circuits are provided with temporary energy storage means. The first control circuit and the second control circuit are controlled by clock signals generated by a clock signal generator. The temporary energy storage means between the earth potential and the supply input of the motor are connected serially so that first switching elements having a first control input, a first input and a second input are interposed between them. One of the outputs of the first temporary energy storage means is connected to the earth potential, the second input of the very last first switching element is connected to the supply input of the motor, and a second input of a second switching element - provided with a second control input - is connected to the first input of each of the first switching elements respectively. The first inputs of the second switching elements are electrically connected together and are connected to the positive output of the storage means. Each of the second inputs of the first switching elements except the second input of the very last first switching element is connected to a first input of a third switching element provided with a third control input. The second inputs of the third switching elements are connected to the earth potential. The second control input and the third control input of the first control circuit as well as the first control input of the second control circuit and one of the outputs of the clock signal generator are connected together. The second control input and the third control input of the second control circuit as well as the first control input of the first control circuit and the other output - with the opposing signal level/amplitude - of the clock signal generator are connected together.

Preferably, the energy source is formed from at least three storage units the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries which are controlled by power supply switching elements controlled by power supply control signals. The storage units are connected to each other and/or to the earth potential serially in the drive mode of operation, and parallel or parallel and serially in the deceleration mode of operation. The switching elements can be relays, CMOS semiconductors, thyristors or bipolar transistors or known switching circuits.

Advantageously, the converter circuit is also adapted to control the revolutions per minute in a known manner. Preferably, the converter circuit is a known control circuit for controlling electric motors which is adapted to control the revolution per minute by pulse-width control.

Advantageously, the control unit is adapted to control more than one motors, at least one of these motors - exclusively in acceleration mode of operation - is operated as motor, and at least one of these motors - exclusively in deceleration mode of operation - is operated as generator.

Preferably, the pulse width of the output signal of the converter circuit is variable.

A detailed description of the invention will be given with reference to the accompanying drawings in which:

Figure 1 is a schematic illustration of the arrangement according to the invention for controlling an electric motor;

Figure 2 is a schematic illustration of the arrangement according to the invention for controlling a motor of a vehicle; Figure 3 shows the first control circuit of the arrangement of Figure 1 ;

Figure 4 shows the arrangement of Figure 2 in more details, where the switching elements are shown schematically;

Figure 5 is a schematic illustration of the general application of the control arrangement according to the invention. The invention is shown in details in Figure 4 while Figures 1-3 and 5 are schematic drawings of the solution according to the invention.

The control unit 3 according to the invention is adapted to control the motor of a vehicle having an electric motor 1 and at least one control element 9, namely a deceleration sensor 10 and/or an acceleration sensor 11. Advantageously, the deceleration sensor 10 is a brake means 12 for example a brake pedal, and the acceleration sensor 11 is an accelerator means 13 for example a gas pedal. When the brake means 12 which is the deceleration sensor 10 of the vehicle is in operation it generates a brake means signal 14 and a brake signal 15 which is proportional to the extent of movement of the brake means 12. Brake signal 15 is transmitted to converter circuit 4. The brake means signal 14 for giving signals of the operation of the brake means 12 may be the output signal of an optical sensor e.g. an opto transistor or a micro-switch which starts working when the brake pedal is pushed. The brake signal 15 which is proportional to the extent of movement of the brake means 12 may be the output signal of an optical or mechanical potentiometer.

The acceleration sensor 11 has outputs for an accelerator means signal 16 when operation of the accelerator means 13 is detected, and for an acceleration signal 17 which is proportional to the extent of movement of the accelerator means

13. The acceleration signal 17 is transmitted to the converter circuit 4. The accelerator means signal 16 may be the output signal of an optical sensor e.g. an opto-transistor or a micro-switch which starts working when the gas pedal is pushed. The acceleration signal 17 which is proportional to the extent of movement of the accelerator means 13 may be the output signal of an optical or mechanical potentiometer.

The energy source of the vehicle is a direct-current storage means 2 which comprises at least two storage units 36 preferably batteries. The motor 1 is operated in motor mode of operation during acceleration while during deceleration it is operated in generator mode of operation. The storage means 2 is connected to motor 1 through the current-limiting circuit 34 and a known DC-DC converter circuit which is connected serially to current-limiting circuit 34, and through control unit 3 and converter circuit 4 which is connected to the control unit 3. The DC-DC converter circuits are not shown in the Figures. The control unit 3 is formed from two control circuits both having the same structure, namely a first control circuit 5 and a second control circuit 6 which operate in push-pull manner. The control circuits 5, 6 are provided with temporary energy storage means 7. The first control circuit 5 and the second control circuit 6 are controlled by a clock signal generated by a clock signal generator 8. Advantageously, the clock signal generator 8 has Q output and negated output Q The temporary energy storage means 7 are connected together serially between the earth potential and the supply input of the motor 1 so that first switching elements 21 having a first control input 18, a first input 19 and a second input 20 are interposed between them. One of the outputs 23 of the first temporary energy storage means 22 is connected to the earth potential, the second input 25 of the very last first switching element 24 is connected to the supply input of the motor 1. A second input 28 of a second switching element 27 - provided with a second control input 26 - is connected to the first input 19 of each of the first switching elements 21 respectively. The first inputs 29 of the second switching elements 27 are electrically connected together and are connected to the positive output of the storage means 2. Each of the second inputs 20 of the first switching elements 21 except the second input 25 of the very last first switching element 24 is connected to a first input 32 of a third switching element 31 provided with a third control input 30. The second inputs 33 of the third switching elements 31 are connected to the earth potential. In the first control circuit 5 the second control inputs 26 are connected to the third control input 30 as well as to the first control input 18 of the first switching elements 21 , 24 of the second control circuit 6 and also to one of the outputs of the clock signal generator 8, in the present example to Q output. In the second control circuit 6 the second control inputs 26 are connected to the third control input 30 as well as to the first control input 18 of the first switching elements 21 , 24 of the first control circuit 5 and also to the other output of the clock signal generator 8, in the present example to negated output Q .

The energy source, i.e. the storage means 2 comprises at least three storage units 36 the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries which are controlled by power supply switching elements 35 controlled by power supply control signals 38 in such a manner that the storage units 36 are connected to each other and/or to the earth potential serially in the drive mode of operation, and parallel or parallel and serially in the deceleration mode of operation. The advantage of using low voltage storage units 36 is that there is no need for a buck-boost circuit (which operates at a loss) between the control unit 3 and the storage units 36, since the cells can be shifted in compliance with the decreasing voltage in the control unit 3 by means of a comparator circuit. The invention can be adapted to control an apparatus 37 (Figure 5) which can be for example a power-supply unit, a voltage converter, a power station, etc. or it can be adapted to control an electric motor 1 (Figure 1). In these cases there is no need for control element 9, brake means 12 and accelerator means 13 (which are indispensable in case of vehicles' control). Further, there is no need to control the storage units 36 in the storage means 2, i.e. the power supply switching elements 35 can be omitted. In order to avoid excessive current load on control unit 3 and storage means 2 a known current- limiting circuit 34 and a serially connected DC-DC converter can be interposed between them.

The power-supply switching elements 35 may be designed similarly to the switching elements used in control unit 3. The switching elements can be CMOS semiconductors, thyristors or bipolar transistors or switching circuit arrangements.

Naturally, simple relays can also be used. However, modern semi-conductors are cheaper, quieter, etc. In case of dual energy supply comprising ultra-capacity, if parallel connected power CMOS semiconductor devices are used for the switching elements of the control unit, then the residual energy of the control unit is only 1.7%. It is less than the residual energy measured at the load which is 2.5 times higher relative to the pulse energy of the energy storage means. The control unit must always be designed so that its output DC voltage should be the integral DC voltage of the load plus the voltage of a temporary energy storage means. If 50% of the effective energy source is applied on the control unit 3, then a saw-tooth signal whose steepness is correspondent to the cumulated voltage of two temporary energy storage means appears at its output with the higher voltage i.e. at the load-side. Decreasing the steepness of a saw-tooth signal can be able reached by increasing the matrix net, which results residual energy growth.

The converter circuit 4 is also adapted to control the revolution number in a known manner. Motorola Inc. describes such converter circuits 4 using integrated circuits MC 33035 or MC 33039. Designing of these can be learnt through the Internet from the home page of Motorola. In case of a brush less DC motor 1 the converter circuit 4 may be accomplished by a known control circuit adapted to control the revolution number of the motor through pulse-width control. Control unit 3 can be used for controlling more than one motor 1. When the vehicle is provided with more than one motor 1 , the motors 1 can be operated so that exclusively in acceleration mode of operation at least one of them is used as motor, and exclusively in deceleration mode of operation at least one of them is used as generator. Implementing of this is well within the knowledge of one skilled in the art.

Control of motor 1 is accomplished by implementing the method according to the invention. The method according to the invention is adapted to control apparatus 37 operated with electric energy. In the present example the method is used for controlling electric motor 1 wherein the energy source of the vehicle is a direct- current storage means 2 which comprises at least two storage units 36 preferably batteries. The storage means 2 is connected to motor 1 through control unit 3 and converter circuit 4 which is connected to the control unit 3 or if it is needed, the storage means 2 is connected to apparatus 37. The nature of apparatus 37 determines whether converter circuit 4 should be installed between control unit 3 and apparatus 37.

The control unit 3 is formed from two control circuits with the same structure, namely a first control circuit 5 and a second control circuit 6 which operate in push-pull manner. The control circuits 5, 6 are provided with temporary energy storage means 7. The first control circuit 5 and the second control circuit 6 are controlled in push-pull manner by a clock signal generated by a clock signal generator 8. In the first control circuit 5, in the first state of the clock signal the Q output of the clock signal generator 8 controls the second control inputs 26 and the third control inputs 30. The second inputs 28 and the first inputs 29 of the second switching elements 27 as well as the first inputs 32 and the second inputs 33 of the third switching elements are connected. In this manner the temporary energy storage means 7 or part of them are connected to each other parallel and at the same time the temporary energy storage means 7 are connected to the storage means 2 thereby recharging the temporary energy storage means 7 to a voltage level close to the voltage level of the storage means 2. When the ultra-capacity operated as temporary energy storage means 7 is activated, i.e. in cold-start mode of operation, the connection between the storage means 2 and the parallel connecting capacities can be programmed with the clock signal so that each clock signal connects only one ultra-capacity operated as temporary energy storage means 7 to storage means 2 at a time, thereby reducing the load on current limiting circuit 34. In the meanwhile in the second control circuit 6 by controlling the first control inputs 18 through the Q output of the clock signal generator 8, the first inputs 19 and the second inputs 20 and 25 of the first switching elements 21 and the last of the first switching elements 24 are connected together. In this manner the temporary energy storage means 7 or part of them are connected serially in the second control circuit 6 and the so produced direct voltage which is many times higher than the voltage of the storage means 2 is transmitted to the apparatus 37. If it is necessary for the operation of the apparatus 37, the voltage of the storage means 2 is transmitted to the converter circuit 4, and in the present example the continuous/intermittent direct voltage appearing at the output of the converter circuit 4 is transmitted to the motor 1.

In the second state of the clock signal the negated output Q of the clock signal generator 8 operates similarly. That is, the temporary energy storage means 7 or part of them are connected serially in the first control circuit, as it has been described previously with reference to control circuit 6, and the so produced direct voltage which is many times higher than the voltage of the storage means 2 - if it is necessary for the operation of the apparatus 37 - is transmitted to the converter circuit 4, and the continuous/intermittent direct voltage appearing at the output of the converter circuit 4 is transmitted to the apparatus 37, in the present example to the motor 1. In the meanwhile the temporary energy storage means 7 or part of them are connected parallel in the second control circuit 6 in the similar manner as it has been described in case of the first control circuit 5, and then they are connected to storage means 2.

The method according to the invention is further adapted to control an electric apparatus for example an electric motor 1 of a vehicle provided with at least one control element 9, namely a deceleration sensor 10 and/or an acceleration sensor 11 , preferably a brake means 12 and/or an accelerator means 13. The energy source is provided by a direct-current storage means 2 comprising at least two storage units 36 preferably batteries. The motor 1 is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration. The storage means 2 is connected to the motor 1 through a control unit 3 and a converter circuit 4 which is connected to the control unit 3. The control unit 3 is formed from two control circuits with the same structure, namely a first control circuit 5 and a second control circuit 6 which operate in push-pull manner, and the control circuits 5 and 6 are provided with temporary energy storage means 7. The first control circuit 5 and the second control circuit 6 are push-pull controlled by a clock signal generated by a clock signal generator 8. In the normal state of the deceleration sensor 10 and/or when the acceleration sensor 11 is operated i.e. in the acceleration mode of operation the procedure described earlier is done, that is:

In the first control circuit 5, in the first state of the clock signal the Q output of the clock signal generator 8 controls the second control inputs 26 and the third control inputs 30. The second inputs 28 and the first inputs 29 of the second switching elements 27 as well as the first inputs 32 and the second inputs 33 of the third switching elements are connected. In this manner the temporary energy storage means 7 or part of them are connected to each other parallel and at the same time the temporary energy storage means 7 are connected to the storage means 2 thereby recharging the temporary energy storage means 7 to a voltage level close to the voltage level of the storage means 2. In the meanwhile the storage units 36 of the storage means 2 are connected serially or serially and parallel to the power supply switching elements 35 depending on the charging voltage or charging current. In Figure 4 only the solution in which the storage units 36 are connected either serially or parallel is shown. Implementing the serial and parallel (mixed) connection of the storage units 36 is well within the knowledge of a person skilled in the art. In this way, when the accelerator means 13 and also the acceleration sensor 11 are operated, that is when accelerator means signals 16 and acceleration signals 17 are transmitted, the storage units 36 are connected serially.

In the meanwhile in the second control circuit 6 by controlling the first control inputs 18 through the Q output of the clock signal generator 8, the first inputs 19 and the second inputs 20 and 25 of the first switching elements 21 and the last of the first switching elements 24 are connected together. In this manner the temporary energy storage means 7 or part of them are connected serially in the second control circuit 6 and the so produced direct voltage which is many times higher than the voltage of the storage means 2 - if it is necessary for the operation of the apparatus 37 - is transmitted to the converter circuit 4 and in the present example the continuous/intermittent direct voltage appearing at the output of the converter circuit 4 is transmitted to the motor 1.

In the second state of the clock signal the temporary energy storage means 7 or part of them are connected serially in the first control circuit 5 by means of the negated output Q of the clock signal generator 8 as it has been described previously, and the so produced direct voltage which is many times higher than the voltage of the storage means 2 - if it is necessary for the operation of the apparatus 37 - is transmitted to the converter circuit 4, and the continuous/intermittent direct voltage appearing at the output of the converter circuit 4 is transmitted to the apparatus 37, in the present example to the motor 1.

In the meanwhile in the second control circuit 6 the temporary energy storage means 7 or part of them are connected to each other parallel and at the same time the temporary energy storage means 7 are connected to the storage means 2 thereby recharging the temporary energy storage means 7 to a voltage level close to the voltage level of the storage means 2. In the meanwhile the storage units 36 of the storage means 2 are connected serially or serially and parallel to the power supply switching elements 35 depending on the charging voltage or charging current. In Figure 4 only the solution in which the storage units 36 are connected either serially or parallel is shown. In this way, when the accelerator means 13 and also the acceleration sensor 11 are operated, that is when accelerator means signals 16 and acceleration signals 17 are transmitted, the storage units 36 are connected serially.

When the deceleration sensor 10 is operated, that is in deceleration mode of operation the following steps are taken: In the first state of the clock signal the temporary energy storage means 7 or part of them are connected serially in the first control circuit 5 by means of the negated output Q of the clock signal generator 8 as it has been described previously, and from the motor which operates as a generator the temporary energy storage means 7 are recharged to the direct voltage level appearing at the output of the converter circuit 4.

In the meanwhile in the second control circuit 6 the temporary energy storage means 7 or part of them are connected together parallel and are connected parallel to the storage means 2. In this manner the energy stored in the temporary energy storage means 7 is charged to the storage means 2 thereby increasing its voltage level to a level close to the operating voltage.

In the meanwhile the storage units 36 in the storage means 2 are connected parallel or parallel and serially to the power supply switching elements

35 depending on the charging voltage or charging current. In Figure 4 only the solution in which the storage units 36 are connected either serially or parallel is shown. In this way, when the brake means 12 and also the deceleration sensor 10 are operated, that is when signals 14 of the brake means 13 and brake signals 15 are transmitted, the storage units 36 are connected together parallel.

In the first control circuit 5, in the second state of the clock signal the Q output of the clock signal generator 8 controls the second control inputs 26 and the third control inputs 30. The second inputs 28 and the first inputs 29 of the second switching elements 27 as well as the first inputs 32 and the second inputs 33 of the third switching elements are connected. In this manner the temporary energy storage means 7 or part of them are connected to each other parallel and at the same time the temporary energy storage means 7 are parallel connected to the storage means 2. In this manner the temporary energy storage means 7 are charged to a voltage level close to the voltage level of the storage means 2. In the meanwhile the storage units 36 of the storage means 2 are connected parallel or serially and parallel by suitably operating the power supply switching elements 35 depending on the charging voltage or charging current. In this way, when the brake means 12 and also the deceleration sensor 10 are operated, that is when signals 14 of the brake means 13 and brake signals 15 are transmitted, the storage units 36 are connected together parallel.

In the meanwhile in the second control circuit 6 by controlling the first control inputs 18 through the Q output of the clock signal generator 8, the first inputs 19 and the second inputs 20 and 25 of the first switching elements 21 and the last of the first switching elements 24 are connected together. In this manner the temporary energy storage means 7 or part of them are connected serially in the second control circuit 6 and the temporary energy storage means 7 are charged from the motor operating as a generator with the intermittent direct voltage appearing at the output of the converter circuit 4. The energy source is formed from at least three storage units 36 the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries. As it has already been mentioned, the storage units 36 are connected to each other serially in the drive mode of operation (acceleration, control), and parallel or parallel and serially in the deceleration mode of operation (neutral, braking) by means of power supply switching elements 35.

The temporary storage means 7 are high capacity condensers or short-time working accumulators.

The motor 1 may be an electric motor of any type, for example a brush less DC motor, brush less AM motor or a double-commutator AC motor with brush. If it is intended for use also as a generator, then it may be an electric motor of any type which is adapted for recharging, for example a brush less DC motor or a cage motor.

The clock signal of the clock signal generator 8 is set to a value between 0.05 and 20 Hz and the frequency value of the clock signal generator is different in the deceleration mode of operation and in the acceleration mode of operation. The advantage of it is that the length of the charging time can be set so that the highest efficiency can be achieved. For example, in case of vehicles, when the motor 1 is switched to the power supply, i.e. in cold-start mode of operation, the ultra- capacity system is utilized primarily as temporary energy storage means 7 so that the energy is charged into the parallel connected temporary energy storage means 7 at least for a period of time which equals to the total working period of the serially connected temporary storage means 7. The similar procedure is done in order to avoid jerking in the deceleration mode of operation. In case of vehicles, detection of the signals of the acceleration sensor 11 is disabled when the deceleration sensor is in operation.

Converter circuit 4 is a known control circuit (e.g. made by Motorola) adapted to control a brush less DC motor 1.

When charging the temporary storage means 2 from the storage means 2, the current of the storage means 2 is led to the temporary energy storage means 7 of either the first control circuit 5 or the second control circuit 6 through a known current limiting circuit 34. In the same manner, when operating the deceleration sensor 10, the current of the temporary energy storage means 7 is led to the parallel or parallel and serially connected storage means 2 through a known current limiting circuit 34, with the exception that when the deceleration sensor 10 is operated, a known buck-boost DC-DC adapter stage is connected serially to the current limiting circuit 34. The advantage of the control unit and the control method according to the invention is that there is no transformer connection, therefore there is no iron and copper loss during operation. The output voltage and current of the control unit according to the invention is completely smooth direct voltage and this voltage and current is led to the motor as opposed to one known solution in which high- frequency alternating voltage the energy flow of which is uneven is transmitted to the motor.

When the energy source which can be a dual energy source is formed from fuel cells, there is no need for many cells in order to control the motor with low loss and high voltage. In case of an accumulator which also can be a dual energy source, for the same reason, there is no need for many batteries. The internal resistance of the energy sources can be kept on low level in both cases.

In case of fuel cells recharging by braking is also possible in such a manner that the control unit is disconnected from the fuel cell, and a control logic should be applied so that the control unit is able to receive a certain level energy, even by full level energy from the motor. When the energy source is an accumulator, by disconnecting the control unit in deceleration mode of operation, the accumulator can be saved of transient current pulses.

Only a control unit of this type can be loaded continuously with power impulses much higher than that of the energy supply of the control unit. The control unit and the method of the invention makes it possible to control a plurality of parallel connected motors which rotate jointly. When the electric motors are operated in the generator mode of operation (engine brake) the generated electric energy can be charged back to the temporary storage means, storage means in a highly efficient manner. The control unit according to the invention can be added to a number of known electric motors.

By means of the control unit the energy from the storage means e.g. battery or other energy source can be transmitted to and fro almost without loss. If an accumulator system is used as temporary energy storage means the components of the effective energy which can be continuously delivered, i.e. the available maximum voltage and current in the opposing but reversible direction are increased and decreased as a function of time. In this manner nearly 100% efficiency is ensured. If an ultra-capacity system is used as temporary energy storage means, then 50% efficiency is obtained, i.e. the maximum effective energy obtainable at the output of the control unit opposite the output connected to the storage means is 50% of the maximum effective energy stored in the storage means. When two control units are used, supply voltage with opposite polarity of a switched mode amplifier - operated by a known high-frequency modulator - can be produced. With this switched mode amplifier the energy can be transmitted to the (AC) motor and back so that the modulators of the switched mode amplifier are controlled by a half-wave sinus signal, and during deceleration the inputs of the AC motor are connected back to the inputs of the modulator. Alternatively, for the load a bridge circuit is used which is controlled by a 4/4 square signal. In case of electric vehicles, e.g. scooters, provided with a circuit of this type their range, speed and the working time can be the multiple of the same of the known ones. The expected range of vehicles provided with engine of 1080 W is: (4/V2)x π x 10² km.

The control unit is a universal converter, since an AC or DC motor with a voltage higher than the low voltage accumulators can not be controlled without loss. Without the control unit a sinus greater than the voltage of the accumulator can not be transformed without loss. The present invention is different from the known transformers in that it is dynamic, it is controlled by clock signals, it is able to store energy and can be operated nearly without loss.

The control unit is able to receive an AC and DC voltage of some 10,000. The temporary energy storage means can be implemented by known ferrite memories, or other coil elements in the control unit. This has an advantage that its energy load functions is mirror symmetric to that of the ultra capacities. If such a control unite in accordance with the invention is connect to a control unit having ultra capacities, then the resulted current-voltage transformation (diagonalization) can be almost 100%. In case of using two control units in the present method, a high frequency cycle control can be applied, and by this way dissipation of semiconductors can be reduced. Connecting high speed (n X 16 GHz) logic gates together the resulted quadrangular signal generator of Fig. 8 can be used in other technical fields, e.g. computer technology. The control method according to the energy process control does not comprise known alternative or digital pulse-width modulators, instead, digital integral calculus is performed, i.e. it generates energy windows. The result of the digital integral calculus, that is the energy windows generated on the load are controlled by the signals of the control devices, the samples of the digital speedometer and a central constant frequency clock signal generator. Consequently, the load is always optimal, and the accelerating energy and the braking energy are utilized in the most economic way. The energy control method can be implemented on XILINX programming platform, and capable to use in ASIC systems, where typically 15000 logic gates are operated. The invention may be realized with CMOS semiconductors, thyristors by using Schottky-diodes for triggering which can control the switching element during switching on/off in the steepest manner.

The control unit when constructed in a miniaturized form by using SMD technology can be used for current/voltage conversion, for upgrading efficiency of solar cells, as a result of which these devices can be operated more economically.

The arrangement of opto-diodes and the processing elements are different issues of design. In case of electric cable supplied vehicles the cable can be eliminated.

LIST OF PARTS

1 electric motor 20 second input

2 storage means 21 first switching elements

3 control unit 25 22 first temporary energy

4 converter circuit storage means

5 first control circuit 23 output

6 second control circuit 24 first switching element

7 temporary energy 25 second input storage means 30 26 second control input

8 clock signal generator 27 second switching element

9 control element 28 second input

10 deceleration sensor 29 first input

11 acceleration sensor 30 third control input

12 brake means 35 31 third switching element

13 acceleration means 32 first input

14 break means signal 33 second input

15 brake signal 34 current-limiting circuit

16 transmitting the signal 35 switching element

17 acceleration signal 40 36 storage unit

18 first control input 37 electric apparatus

19 first input 38 supply control signal

Claims

1. Method for controlling an apparatus (37) operated with electric energy, for example an electric motor (1), wherein the energy source is provided by a direct-current storage, means (2) comprising at least two storage units (36) preferably batteries, the storage means (2) is connected to the apparatus (37) through a control unit (3) and a converter circuit (4) connected to said control unit (3) characterized in that said control unit (3) comprises a first control circuit (5) and a second control circuit (6) both having the same structure but operating in pull- push manner, said control circuits (5, 6) are provided with temporary energy storage means (7), and said first control circuit (5) and said second control circuit

(6) are controlled in push-pull manner by a clock signal generated by a clock signal generator (8) in such a manner that: - in the first state of the clock signal said temporary energy storage means (7) of said first control circuit (5) or part of them are connected to each other parallel, and said temporary energy storage means (7) are connected to said storage means (2) thereby recharging said temporary energy storage means (7) to a voltage level close to the voltage level of said storage means (2), in the meanwhile said temporary energy storage means

(7) of said second control circuit (6) or part of them are connected to each other serially and the so produced direct voltage which is many times higher than the voltage of said storage means (2) is transmitted to said converter circuit (4) and the continuous/intermittent direct voltage appearing at the output of said converter circuit (4) is transmitted to said motor (1); - in the second state of the clock signal said temporary energy storage means (7) of said first control circuit (5) or part of them are connected to each other serially and the so produced direct voltage which is many times higher than the voltage of said storage means (2) is transmitted to said converter circuit (4) and the intermittent direct voltage appearing at the output of said converter circuit (4) is connected to said motor (1) while said temporary energy storage means (7) in said second control circuit (6) or part of them are connected to each other parallel and are connected to said storage means (2).

2. Method for controlling an electric apparatus (37) for example an electric motor (1) of a vehicle provided with at least one control element (9), namely a deceleration sensor (10) and/or an acceleration sensor (11), preferably a brake means (12) and/or an accelerator means (13), wherein the energy source is provided by a direct-current storage means (2) comprising at least two storage units (36) preferably batteries, or fuel cell, said (1) motor is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration, further said storage means (2) is connected to said motor (1) through a control unit (3) and a converter circuit (4) which is connected to the control unit(3), characterized in that said control unit (3) is formed from a first control circuit (5) and a second control circuit (6) both having the same structure but operating in push-pull manner, said control circuits (5, 6) are provided with temporary energy storage means (7), further said first control circuit (5) and said second control circuit (6) are push-pull controlled by a clock signal generated by a clock signal generator (8) in such a manner that in the normal state of said deceleration sensor (10) and/or when said acceleration sensor (11) is operated i.e. in the acceleration mode of operation: - in the first state of the clock signal said temporary energy storage means (7) of said first control circuit (5) or part of them are connected to each other parallel, said storage units (36) in said storage means (2) are connected serially or serially and parallel and said temporary storage means (7) are connected to said storage means (2) thereby recharging said temporary energy storage means (7) to a voltage level close to the voltage level of said storage means (2), while said temporary energy storage means (7) of said second control circuit (6) or part of them are connected to each other serially, and the so produced direct voltage which is many times higher than the voltage of said storage means (2) is transmitted to said converter circuit (4), and the continuous/intermittent direct voltage appearing at the output of said converter circuit (4) is transmitted to said motor (1), - in the second state of the clock signal said temporary energy storage means (7) of said first control circuit (5) or part of them are connected to each other serially, and the so produced direct voltage which is many times higher than the voltage of said storage means (2) is transmitted to said converter circuit (4), and the intermittent direct voltage appearing at the output of said converter circuit (4) is connected to said motor (1) while said temporary energy storage means (7) in said second control circuit (6) or part of them are connected to each other parallel which are then connected to said serially or serially and parallel connected storage units (36) of said storage means (2); when said deceleration sensor (10) is operated i.e. in deceleration mode of operation: - in the first state of the clock signal said temporary energy storage means (7) of said first control circuit (5) or part of them are connected to each other serially and said temporary storage means (7) are recharged from said motor (1) operating as a generator to the direct voltage appearing at the control unit side output of said converter circuit (4), in the meanwhile said temporary storage means (7) in said second control circuit (6) or part of them and said parallel or parallel and serially connected storage units (36) of said storage means (2) are connected parallel, and the energy stored in said temporary storage means

(7) is transmitted to said storage means (2) - in the second state of the clock signal said temporary storage means (7) of said first control circuit (5) or part of them and said parallel or parallel and serially connected storage units (36) of said storage means (2) are connected parallel, and the energy stored in said temporary energy storage means (7) is transmitted to said storage means (2), while said temporary energy storage means (7) of said second control circuit (6) or part of them are connected serially and the voltage appearing at the outputs of said motor (1) operating as a generator is connected to said temporary energy storage means (7) through said converter circuit (4) and the intermittent direct voltage appearing at the output of said converter circuit (4) is charged into said temporary energy storage means (7).

3. Method according to claims 1 or 2 characterized in that said energy source is formed from at least three storage units (36) the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries, said storage units (36) are connected to each other serially in the drive mode of operation, and parallel or parallel and serially in the deceleration mode of operation by means of power supply switching elements (35).

4. Method according to any of claims 1-3 characterized in that said temporary storage means are high capacity condensers or short-time working accumulators.

5. Method according to any of claims 1-4 characterized in that said motor (1) may be an electric motor (1) of any type, for example a brush less DC motor, brush less AM motor or a double-commutator AC motor with brush.

6. Method according to any of claims 2-5 characterized in that said generator may be an electric motor (1) of any type which can be operated as a generator, for example a brush less DC motor or a cage motor.

7. Method according to any of claims 2-6 characterized in that the clock signal of said clock signal generator (8) is set to a value between 0.05 and 20 Hz and the frequency of the clock signal generator (8) in the deceleration mode of operation and in the acceleration mode of operation is different.

8. Method according to any of claims 1-7 characterized in that after said motor (1) is switched to the power supply - on activation i.e. in cold-start mode of operation - an ultra-capacity system is utilized primarily as temporary energy storage means (7) so that the energy is charged into the parallel connected temporary energy storage means (7) at least for a period of time which equals to the total working period of the serially connected temporary storage means (7).

9. Method according to any of claims 2-8 characterized in that in deceleration mode of operation detection of the signal (16) of the acceleration means (13) is disabled.

10. Method according to any of claims 1-9 characterized in that said converter circuit (4) is a known motor control circuit designed for a brush less DC motor.

11. Method according to any of claims 1-10 characterized in that the current from said storage means (2) is charged into said temporary energy storage means (7) of said first and second control circuits (5, 6) through a known current-limiting circuit (34).

12. Method according to any of claims 2-11 characterized in that when said deceleration sensor (10) is operated the current of said temporary energy storage means (7) is led into said parallel or parallel and serially connected storage means (2) through a known current-limiting circuit (34) and a known DC-DC converter, e.g. buck-boost circuit connected serially to the current-limiting circuit (34).

13. Control unit (3) for controlling an electric apparatus (37) for example an electric motor (1) of a vehicle provided with at least one control element (9), namely a deceleration sensor (10) and/or an acceleration sensor (11), preferably a brake means (12) and/or an accelerator means (13), said deceleration sensor (10) of the vehicle has outputs for transmitting the signals (14) of said brake means (12) when sensing the operation of said brake means (12) and a brake signal (15) which is proportional to the extent of movement of said brake means (12), and said acceleration sensor (11 ) of the vehicle has outputs for transmitting the signals (16) of said accelerator means (13) when sensing the operation of said accelerator means (13) and an acceleration signal (17) which is proportional to the extent of movement of said accelerator means (13), the energy source of the vehicle is provided by a direct-current storage means (2) comprising at least two storage units (36) preferably batteries, said motor (1) is operated in motor mode of operation during acceleration and in generator mode of operation during deceleration, said storage means (2) is connected to said motor (1) through a control unit (3) and a converter circuit (4) which is connected to said control unit (3), characterized in that said control unit (3) is formed from two control circuits, a first control circuit (5) and a second control circuit (6) both having the same structure but operating in push-pull manner, and said control circuits (5, 6) are provided with temporary energy storage means (7), said first control circuit (5) and said second control circuit (6) are controlled by clock signals generated by a clock signal generator (8), said temporary energy storage means (7) between the earth potential and the supply input of said motor (1) are connected serially so that first switching elements (21) having a first control input (18), a first input (19) and a second input (20) are interposed between them, one of the outputs (23) of the first temporary energy storage means (22) is connected to the earth potential, the second input (25) of the very last first switching element (24) is connected to the supply input of said motor (1), further a second input(28) of a second switching element (27) - provided with a second control input (26) - is connected to the first input (19) of each of said first switching elements (21) respectively, the first inputs

(29) of the second switching elements (27) are electrically connected together and are connected to the positive output of said storage means (2), each of the second inputs (20) of said first switching elements (21) except the second input (25) of the very last first switching element (24) is connected to a first input (32) of a third switching element (31) provided with a third control input (30), the second inputs

(33) of said third switching elements (31) are connected to the earth potential, further the second control input (26) and the third control input (30) of said first control circuit (5) as well as the first control input (18) of said first switching element (21 , 24) of said second control circuit (6) and one of the outputs of said clock signal generator (8) are connected together, while the second control input (26) and the third control input (30) of said second control circuit (6) as well as the first control input (18) of said first switching element (21 , 24) of said first control circuit (5) and the other output - with the opposing signal level - of said clock signal generator (8) are connected together.

14. Control unit according to claim 13 characterized in that the energy source is formed from at least three storage units (36) the total voltage amount of which is 36 V, for example three 12 V batteries or eight 4.5 V batteries which are controlled by power supply switching elements (35) controlled by power supply control signals (38) so that the storage units (36) are connected to each other and/or to the earth potential serially in the drive mode of operation, and parallel or parallel and serially in the deceleration mode of operation.

15. Control unit according to any of claims 13-14. characterized in that said switching elements (21 , 24, 27, 31) can be relays, FET transistors, thyristors or bipolar transistors, or switching circuits formed from combinations of these in a known manner.

16. Control unit according to any of claims 13-15 characterized in that said converter circuit (4) is also adapted to control the revolutions per minute in a known manner.

17. Control unit according to claim 16 characterized in that said converter circuit (4) is a known control circuit also adapted to control the revolutions per minute by pulse-width control for controlling the electric motor applied.

18. Control unit according to any of claims 13-17 characterized in that said control unit (3) is adapted to control more than one motors (1).

19. Control unit according to any of claims 13-18 characterized in that the pulse width of the output signal of said converter circuit (4) is variable.

20. Control unit according to any of claims 13-19 characterized in that the vehicle controlled by said control unit (3) is provided with more than one motors (1) and at least one of said motors - exclusively in acceleration mode of operation - is operated as motor, and at least one of said motors - exclusively in deceleration mode of operation - is operated as generator.