MXPA05004094A - High frequency battery charger and method of operating same. - Google Patents

Abstract

A high frequency charger includes a charge circuit (12) for charging a depleted battery (21) and a boost circuit (16) for jumpstarting a vehicle. Two separate high frequency transformers (14, 18) are provided for the charge (12) and boost circuits (16). A selector switch (22, 24) selectively activates at least one of the charging circuit and the boost circuit.

Description

before the end of the time limit to amend the claims For codes of two letters and other abbreviations, refer to them and be published in case of receipt of the same "Guide Notes in the Codes and Abbreviations" that appear on the pio of each regular issue from the PCT Gazette. (88) Date of publication of the international search report: July 8, 2004 HIGH FREQUENCY BATTERY CHARGER AND METHOD FOR YOUR OPERATION BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a battery charger or a booster and in particular to a high frequency charger.

TECHNICAL BACKGROUND There are currently dual-point battery chargers. When operated in a first mode, the battery charger supplies a high current output for a short duration of time. This short duration, high current can be used to start a vehicle with a depleted battery. In a second mode, the battery charger provides a low current output that is used to recharge the battery until it is fully charged. The known double-mode battery chargers typically use a single large transformer to acquire dual-mode capability. The single transformer is usually a linear type transformer. A contact of a primary winding of the transformer is loaded in order to obtain the double capacity with the linear type transformer. As the contact changes, the transformer, the output voltage, and therefore Ohm's law, changes the output current of the transformer resulting in double-mode capability. The use of a single transformer for both modes of operation has the advantage of being very cost effective and very efficient.

However, this solution also has several disadvantages. One of the disadvantages is that the known single-transformer battery chargers are very large and annoying. Standard linear transformers require iron for their cores, which adds weight to the battery charger. They also require orders of magnitude of more wire to form their windings compared to high frequency loaders, which again adds weight to the battery charger.

Furthermore, although the linear transformer provides a high current output, the high current output can only be provided for a very short period of time. As the transformer operates in the high current mode, it generates an excessive amount of heat. In fact, it can generate so much heat that the transformer actually melts. If melting occurs, the transformer will no longer operate in high current mode or low current mode. Linear transformers also present many leaks in terms of magnetic losses and stray current losses, resulting in inefficiency.

In addition, to charge the battery of a car that has insufficient electrical power by providing power from another source of energy, such as a battery charger, the power source and the battery must be connected through a pair of electrical wires, which typically have clamps on its ends for connection to the battery. Making this connection can be very dangerous if there is a problem with the connection. For example, it is well known that sparks or arcs are often present when a connection is attempted between a battery charger and a battery. Additionally, sparks or arcs can occur when the clamps connect to the battery with an inverse polarity. Sparks or arcs can also occur even after an apparently good connection has been made. Sparks or arcs can occur due to corroded or improperly made terminal connections.

In the past, the use of a delay circuit or "soft start" was used to avoid sparks. A delay circuit prevents the flow of energy to the battery until a connection has been made between the battery and the battery charger. This method helps avoid sparks when the initial connection of the battery and the battery charger is made. However, does not prevent sparks from occurring as a result of badly made or corroded connections, whose existence can only be determined after the current flow starts. Sparks or arcs can result in damage to the battery and under certain circumstances an explosion, fire and damage to the vehicle or person may occur. - 3 - In addition, a characteristic of liquid electrolyte type batteries, particularly acid and lead batteries used in vehicles, is that the chemical compound deposits slowly accumulating on the plates to partially or completely cover and displace the normal plate surfaces. The recharging of low current is inadequate insofar as, as such, it can not sufficiently eliminate such deposits that, with the passage of time, crystallize and cause a shock of the battery plates interfering with the movement of the electrolyte. When this happens, a battery still seems to have a charge and even the electrolyte can be verified and appear correct, but the battery no longer holds the charge because the plates are actually shorted. Batteries that use other electrolytes also face problems of correcting, maintenance and loading that need to be solved successfully.

Therefore, there is a need for a method to release the deposits that accumulate on the surfaces of the plates, where the deposits return to the solution or decompose. There is also a need for a battery charger in a simple and lightweight double mode. The battery charger must be able to provide a high current output that is sufficient to start a car or other vehicle with a dead battery, which is still easy to build and safe to operate.

According to a variation of the preceding embodiment of the invention, a high frequency charger including a charging circuit and a reinforcement circuit is provided. In this mode, the charging circuit and the reinforcement circuit are constructed using a single high-frequency transformer having two windings on its side, primary, a load winding and a reinforcement winding. The load winding and the reinforcement winding effectively (together with the single secondary winding) form the first and second high frequency transformers of the preceding embodiment of the invention (and can therefore be considered as the two separate transformers in other embodiments). of the invention). The reinforcing winding is adapted to provide high current that can be used to start a vehicle with exhausted battery. - 4 - DEFINITIONS In the description of the invention the following definitions are applicable through it.

A "computer" refers to any device that is capable of accepting a structured entry, processing structured input according to prescribed rules, and producing processing results as an output. Examples of a computer include a computer; a general-purpose computer; a supercomputer; a mainframe computer; a superminicomputer; a minicomputer; a work station; a microcomputer; a processor; A server; an interactive television; a hybrid combination of a computer and an interactive television and hardware (physical elements) specific to the application that emulate a computer or software (programs). A computer can have a single processor or multiple processors, which can operate in parallel or not in parallel. A computer is also referred to as two or more computers connected via a network to transmit or receive information between computers. An example of such a computer includes a distributed computer system for processing information through computers linked by a network.

A "computer readable medium" refers to any storage device used to store data accessible by a computer. Examples of a computer-readable medium include a magnetic hard drive; a flexible disk, an optical disk such as a CD-ROM or a DVD; a magnetic tape; a memory chip (for example ROM or RAM); and a carrier wave used to carry computer-readable electronic data, such as those used in the transmission and reception of emails or when accessing a network.

The term "software" refers to the rules prescribed to operate a computer. Software examples include the software itself; code segments; instructions; computer programs and a logic circuit - 5 - programmed. A "computer system" refers to a system that has a computer, wherein the computer comprises a computer readable medium that constitutes the software to operate the computer.

BRIEF DESCRIPTION OF THE INVENTION In accordance with one embodiment of the invention, a high frequency charger is provided for charging a battery. The charger comprises a charging circuit that includes a first high frequency transformer. A first switch commutes to the first high frequency transformer at a first frequency. The charger also includes a means for measuring the charging speed of the battery; a means to determine the amount of time the battery has been charged; means for measuring a battery voltage and a means for detecting an excessive time fault if the charging speed is higher than a predetermined current, the battery has been charged for a longer period than a predetermined amount of time and if the Battery voltage is greater than or equal to a predetermined voltage.

In another embodiment, the high frequency charger comprises: a charging circuit including a first high frequency transformer; a first switch that switches to the first high frequency transformer at a first frequency; a means to measure the charging speed of the battery; means for determining an amount of time that has been charged to the battery; a means for measuring a battery voltage; and a means for detecting a short-range cell-type battery failure if the charging speed is greater than a predetermined current, if the battery has been charged for a period greater than a predetermined amount of time or if the voltage of the battery is less than or equal to a predetermined voltage.

In another embodiment, the high frequency charger for charging a battery comprises a charging circuit including a first high frequency transformer; a first switch that switches to the first high frequency transformer at a first frequency; clamps to connect the charger to the battery, a means to measure the voltage in the clamps; a means to indicate a battery failure in poor condition if voltage is not detected in the clamps.

In another embodiment, the high frequency charger comprises a charging circuit that includes a first high frequency transformer; a first switch that switches the first high frequency transformer to a first frequency; means for measuring a battery charge current; means for determining an amount of time that has been charged to the battery; a means for measuring a battery voltage; and means for detecting an open cell battery failure if the charging current is less than the predetermined current, if the battery has been charged for a period greater than the predetermined amount of time or if the battery voltage is greater than or equal to a predetermined voltage.

In accordance with one embodiment of the invention, a high frequency charger including a charging circuit and a boost circuit is provided. In a preferred embodiment, the charging circuit includes a first high frequency transformer. A switch switches this first high frequency transformer to a predetermined frequency. The boost circuit includes a second high frequency transformer which is separated from the first high frequency transformer in the charging circuit. The first and second high frequency transformers are operated in a similar manner. However, the reinforcing circuit is adapted to provide a high current that can be used to start a vehicle with a depleted battery.

According to a variation of the preceding embodiment of the invention, a high frequency charger including a charging circuit and a reinforcement circuit is provided. In this mode, the charging circuit and the reinforcement circuit are constructed using a single high frequency transformer having two windings on its primary side, a load winding and a reinforcement winding. The load winding and the reinforcing winding 7 effectively (together with the secondary sole winding) form the first and second high frequency transformers of the preceding embodiment of the invention (and can therefore be considered as two separate transformers in other embodiments of the invention). The reinforcing winding is adapted to provide a high current that can be used to start a vehicle with a depleted battery.

In a preferred embodiment, a PWM controller provides an activation signal to the switch so that the load circuit transformer switches to transmit a pulse. The output pulse of the charging circuit can be used to condition the battery.

As noted, the transformer in the charging circuit and the transformer in the reinforcing circuit are preferably separated from each other, that is, there are two associated transformers and circuits. In this way, the battery charger does not depend on the same transformer for the standard charge and for the reinforcement. For example, if the transformer in a conventional charger burns while performing the reinforcement function, all charger functionality may be lost, since one transformer is used for both functions. However, in this mode, any of the transformers still ftinciona even if the other transformer is disabled for some reason.

A control circuit for a high frequency charger is also provided. In an exemplary embodiment, the control circuit includes a pulse width modulator (PWM) controller having a reference voltage input, a control input, and an output for a control signal. A switch receives the control signal and is activated or inactive in response to the control signal. A voltage divider network divides the voltage applied to the reference voltage input and to the control output. A duty cycle of the control signal output from the PWM controller varies based on the percentage of the reference voltage that is applied to the control. - 8 - In a further embodiment, the voltage divider network comprises a first resistor having a first terminal connected to a reference voltage input and a second terminal connected to a control input. Each of a plurality of second resistors has a first terminal connected to the second terminal of the first resistor and a second terminal. A plurality of transistors are also provided, each with a first electrode connected to the second terminal of one of the second resistors, a second electrode that is connected to ground and a third electrode that receives an enable signal. The enabling signal activates or inactivates the transistors, selectively connecting them to one of the second resistors with ground connection.

In another embodiment, a method for reducing the formation of an arc in a battery charger is described, comprising: providing a test current that is less than the charging current is from the battery charger to the battery; detect if the test current is present in the battery; if the test current in the battery is not detected, and indicates a fault; and if a test current is detected in the battery, the test current is increased by a predetermined amount and the sensor is returned to the detection stage.

According to another aspect of the invention, a computer readable storage medium is provided for use with a computer to control a high frequency charger including a charging circuit having a first high frequency transformer; a first switch that switches to the first high frequency transformer at a predetermined frequency to produce a load signal in a first mode of operation; the charging circuit operates in at least one of a pulse mode and a charge mode; and a selector for selecting one of the charge mode and the pulse mode, the computer readable information storage means stores a computer readable program code to cause the computer to perform the steps of: detecting a selected mode of operation for the charger; and when the pulse mode is selected: a) generate a driving signal for the first switch for a first period of time; b) disable the first switch for a second period of time; and c) return to stage a).

According to a further aspect of the invention, a computer readable information storage means is provided for use with a computer controlling a high frequency charger comprising a charging circuit that includes a high frequency transformer; and a switch that switches to the high frequency transformer at a predetermined frequency, the computer readable information storage means stores a computer readable program code to cause the computer to perform the steps of: verifying a flag (flag) indicating that the battery is in a state of bulk charge or a state of charge of absorption; if the battery is in a state of bulk charging, the duty cycle of a driving signal for the first switch is increased if the current provided by the battery charger is less than the desired current; the duty cycle of the driving signal for the first switch is decreased if the current provided by the battery charger is greater than the desired current; an indicator (flag) is set indicating that the battery is in the absorption charging stage when the battery voltage is greater than or equal to a predetermined voltage and has been charged for a predetermined period of time, otherwise it ends the loading process; if the battery is in the absorption charging stage, the duty cycle of the activating signal for the first switch decreases if the battery voltage is greater than or equal to a predetermined voltage; increases the duty cycle of the driving signal for the first switch if the battery voltage is less than the predetermined voltage; and stops the charging process when the battery has been charged for a period greater than a predetermined time.

According to a further embodiment of the invention, the computer readable information storage medium for use with a computer controlling a high frequency charger comprising a charging circuit includes a first frequency transformer; a first switch that switches the first high frequency transformer to a first frequency; a boost circuit that includes a second high frequency transformer; a second switch that switches to the second high-frequency transformer at a second frequency, and a selector to select one of a charging mode to charge an exhausted battery and a boost mode to supply a boost current to start a vehicle with the battery exhausted, the computer readable storage medium stores the computer readable program code to cause the computer to perform the steps of: detecting a selected mode of operation; if the booster mode is selected, control the booster circuit to supply the booster current to the depleted battery; check if there is a rapid increase in voltage after the vehicle has been started; if a rapid increase in voltage is present, indicate that the alternator is working properly; if the rapid increase in voltage is not present, indicate that the alternator is not working properly.

According to another embodiment of the invention, a high-frequency charger for charging a battery comprises a charging circuit that includes a first high-frequency transformer; a first switch that switches the first high frequency transformer to a first frequency; a filter coupled to the first and second high frequency transformers to pass a DC voltage signal (direct current); a means for coupling a resistor in parallel with the battery; a means to measure the voltage of the battery while the battery is coupled to the resistor; and a means for correlating the measured voltage with a CCA value.

The above features and other characteristics of the invention, together with the concomitant benefits and advantages will become apparent from the following detailed description when considered with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 is a k diagram showing a double frequency charger, according to one embodiment of the present invention. - eleven - Figure 2 is a diagram of the waveforms generated by the control circuits, according to an embodiment of the present invention.

Fig. 3 is a schematic circuit in the form of a partial k diagram showing one embodiment of the pulse enable circuit and the pulse width modulation controller shown in Fig. 1.

Figure 4 is a k diagram of a battery charger according to a further embodiment of the invention.

Figure 5 is a k diagram of a battery charger according to a further embodiment of the invention.

Figures 6 and 7 show flow diagrams of a method according to an embodiment of the invention.

Figure 8 is a flow chart of a method according to another embodiment of the invention.

Fig. 9 is a partial k diagram showing an alternative implementation of the dual high-frequency charger embodiments of Figs. 1 and 4.

DETAILED DESCRIPTION OF THE INVENTION Now with reference to Figure 1, a high frequency charger is shown, according to one embodiment of the invention, which includes a portion 8 of high frequency transformer. The high frequency transformer portion 8 typically receives a DC signal at its input. The DC signal can be supplied from a battery or from an AC input. In the embodiment illustrated, an AC inlet 2, which can be provided by a typical wall outlet, is coupled to a filter 4, for example, a pi filter or an LC filter. The filter 4 is used to uniformly return and clean the AC inlet. An AC signal output from the filter 4 is provided to conventional rectifiers and filtering capacitors 6 to rectify the AC signal. The rectifier is preferably a full wave rectifier of the type known to those skilled in the art and provides a DC output, for example, of approximately 150 volts DC.

The rectified and filtered full-wave DC output from the rectifier 6 is provided to the portion 8 of the high-frequency transformer of the battery charger. Port 8 of the high frequency transformer includes a charging circuit 12 and a boost circuit 16. The boost circuit 16 is used to provide a high current boost that can be used to start a vehicle with a spent battery. The charging circuit 12 is used for the normal battery charger. The operation of the boost circuit 16 and the load circuit 12 can be carried out sequentially, in any order, or simultaneously. The charging circuit 12 and the boost circuit 16 each include a high frequency transformer 14, 18, respectively. A DC output of the filtering rectifiers and capacitors 6 is provided to each of the high frequency transformers 14, 18.

The transformers typically receive an AC input and provide an AC output. For example, a transformer plugged into a standard wall receptacle is provided with an AC input of 120 volts and outputs with an AC signal that depends on the secondary winding of the transformer. In this way, the high frequency transformers 14, 18 need to be manipulated to behave in such a way that the DC signal of the rectifiers 6 has an appearance similar to that of an AC input. This manipulation is accompanied by switching the DC output of the rectifier 6 through the high frequency transformers. The transformers are turned on and off at a high frequency, for example about 20 kHz and above. This switching causes the transformers to behave as if their - 13 - input were outside AC.

This switching can be carried out using essentially any type of switch, for example, a field effect transistor (FET) or other electronic switch. The high-frequency transformers 14, 18 of the embodiment illustrated are switched by switches 22, 24, respectively, coupled thereto. The switches 22, 24 in turn are controlled by PWM controllers 23, 25. The PWM controller can be, for example, a Motorola TL 494 type controller or a separate controller. The PWM controller generates a PWM activation signal to turn the switches on and off.

The charging circuit 12 is capable of operating in two modes, a charging mode and a pulse mode. In charging mode, charging circuit 12 operates to charge a battery. In the pulse mode, the charging circuit 12 operates to condition or desulph a battery. A user may select one of these two modes by means of a selector 30. The selector 30 provides the user's selection to a pulse enable circuit 28. The pulse enable circuit 28 controls the PWM controller 23 according to the type of charging mode or operating pulse mode that is selected for the charging circuit 12.

When the pulse mode is selected, the pulse enable circuit 28 controls the PWM controller 23 so that it is alternately active and transmits a driving signal to the switch 22 and so that it is inactive and does not activate the switch 22. The enabling cycle / disabling switch switching 22 is repeated under the control of PWM controller 23. Figure 12 illustrates exemplary output waveforms for the pulse enable circuit 28 and the PWM controller 23. In the pulse mode, the pulse enable circuit 28 is activated such that its output signal Wi varies between the low and high states, as shown in Fig. 2. The PWM controller 23 is activated depending on the signal Wi of output of circuit 28 of pulse enable. During a first period of time ti, the output Wi of the pulse enable circuit 28-14 is high and the PWM controller 23 is activated to generate a PWM trigger signal W2, as shown in Fig. 2. The signal W2 driver activator 23 PWM is provided to switch 22, for example, for the gate of an FET comprising switch 22, for its on and off, for example, the activation signal from PWM controller 23 may have a cycle of work of less than 15% so that the FET is turned on for a very short period of time, transmits current to the battery and then disables it. The driving signal modulates the FET. During a second period of time t2, the output Wi of the pulse enable circuit 28 is low and deactivated to the PWM controller. No activation signal is provided to the FET and the FET remains off. Setting pulses of the high frequency transformer in this way shreds its output to condition the battery.

During the pulse mode, a series of pulses of output current are generated by the battery charger and are provided to the discharged battery 21. The current pulses may have a frequency of about one pulse per second and an increase time of about 100 volts / microsecond or less.

When the charging mode is selected by means of the selector 30, the PWM controller 23 is preferably always activated. The operation of the PWM controller 23 can be controlled, in part, by feedback from a battery 21 that is charged. The duty cycle of the driving signal generated by the PWM controller 23 is varied based on the charging state of the battery. A feedback signal from the battery that is charged 21 to the PWM controller 23 provides the information regarding the charging status of the battery. The more energy the battery needs, the greater the duty cycle; and the lower the power needed by the battery, the lower the duty cycle. The switch 22 switches to the transformer 14 in accordance with the activating signal to charge the battery.

Referring again to Figure 1, the reinforcement circuit 16 is now described. The boost circuit 16 provides a high current pulse that can be used to start an exhausted battery. The boost circuit 16 is enabled by a standard / boost selector 26 which can be operated by the user. When activated, the selector 26 enables the PWM controller 25 to generate a signal that drives a switch 24 which, in an exemplary embodiment, comprises an FET. The frequency of the activation signal of the FET 24 in the high-energy booster circuit may be the same or it may be different from the frequency of the activation signal for the switch 22 in the charging circuit, for example approximately 20 kHz or even higher. When the same frequency is used, the clock frequency for the PWM controller 23 is associated with the load circuit 12 to be shared by the PWM controller 25 for the high-energy boost circuit 16.

The high-energy boost circuit 16 receives a DC input from the rectifier 6. The DC input is provided to a high-frequency transformer 18 in the high-energy boost circuit 16. Preferably, the high frequency transformer 18 in the high energy boost circuit 16 is separated from the high frequency transformer 14 in the charging circuit 12. The high frequency transformer 18 in the high energy boost circuit 16 generates a relatively high current with respect to the output of the load circuit 12. For example, the current generated from the boost circuit 16 may vary from about 30 amps to about 500 amps, compared to about 2-25 amps for the charging circuit 12. Additionally, the output of the boost circuit 16 is typically generated only for a short period of time, for example, of about 3-40 seconds. Accordingly, the high frequency transformer 18 and the high energy boost circuit 16 is preferably slightly larger than the high frequency transformer 14 in the charging circuit 12.

The high frequency transformer 18 has such a duty cycle that it can be half the time on and half the time off, although there is always an output from the transformer that is rectified, filtered and used to recharge the battery. The PWM controller 25 typically shuts off for approximately 60-90% -16- of the time and turns on for approximately 10-40%, and then switches off again to reach, again, the duty cycle for the high frequency charger . During 10-40% of the time that the PWM controller 25 is on, the switch 24 switches to the high frequency transformer. This provides a high current pulse that leaves the high frequency transformer through the rectifier 19 to the battery to be charged.

Both the transformer 14 in the charging circuit 12 and the transformer 18 in the boost circuit 16 generate an AC signal that needs to be converted to DC, so that it can be used by the battery. Therefore, the output of the high frequency charger in the charging circuit passes through standard rectifiers and filter capacitors 19, 20 to provide a DC output. The high frequency transformer 14 in the charging circuit 12 is preferably a relatively small transformer capable of supplying a relatively low current, preferably between about 2 and about 30 amperes, and a voltage corresponding to what the battery needs, for example, approximately 14.2 volts. The switching operation for the high-frequency transformer 18 in the high-energy reinforcement circuit 16 by the transformer 24 is preferably performed in a manner similar to that described with respect to the charging circuit 12, but due to its different construction, it results in a current output of the booster circuit from about 30 amps to about 500 amps.

Returning now to FIG. 3, an example of circuitry (set of circuits) which may comprise the pulse enable circuit 28 is described. In the embodiment illustrated, the pulse enable circuit 28 incorporates a manual control of the PWM controller 23. In this way, a user can control the charging of the battery. The PWM controller 23 has an input 31 which applies a reference voltage, and a dead time control input 32. The dead time control input 32 controls the duty cycle of the driving signal from the output 34 of the PWM controller 23 based on a percentage of the reference voltage that is applied to the dead time control input -17- . For example, when full reference voltage is applied to the dead time control input 32, the duty cycle of the PWM counter-off output signal 23 is set to zero, switch 22 is turned off (Fig. 1) and No voltage is applied to the battery that is being charged. When no voltage is applied to the dead time control input 32, the duty cycle of the output signal of the PWM controller 23 is set to its maximum and maximum current is applied to the battery. The duty cycle of the driving signal from the output 34 of the PWM controller 23 varies between these two ends depending on the percentages of the reference voltage that is applied to the dead time control input 32.

In the embodiment shown in Figure 3 a combination of a counter circuit 36 and a number of transistors 38-41 is used to control the percentage of reference voltage that is applied to the dead time control input 32. The counter 36 is preferably a low active device with diodes, or a high output active decade counter, for example, a 4017B CMOS IC. Of course other distributions are possible within the scope of the invention. The outputs of the counter 36 are each connected to the transistors. In Figure 3, four transistors 38-41 are shown for four outputs of the counter 36. The number of corresponding outputs and transistors may vary depending on the type of counter used. Each transistor can be of type BJT or FET type. A control electrode of each transistor 38-41 is connected through a resistor 42-45 corresponding to a separate output of the counter 36. A first electrode in the main current path of each transistor 38-41 is coupled to ground. A second electrode in the main current path of each transistor 38-41 is coupled to a resistor 46-49, respectively. Each of the resistors 46-49 is coupled to a dead time control input 32 of the PWM controller 23. Each of the resistors 46-49 is also coupled to the resistor 51, which in turn is coupled to the reference voltage input 30 of the PWM controller 23.

The resistors 46-49, the associated transistors 38-41 and the resistor 51 form a voltage divider. The voltage difference between the reference voltage input 30 and - 18 - the dead time control input 32 is controlled by the values of the resistors 46-49. For example, each of the resistors 46-49 can be selected so that it has a different resistance. Voltage drops through resistors 46-49 will vary accordingly. Therefore, the percentage of the reference voltage applied to the dead time control input 32 varies depending on which transistor 38-41 is turned on and the value of its associated resistor 46-49.

For example, as the counter 36 is operating, one of the outputs of the counter 36 becomes active and turns on the respective transistor 38-41 connected to said output. Only one of the transistors 38-41 can be switched on at the same time. The on transistor 38-41 provides a current path from the dead time control input 32, through its respective resistor 46-49, to ground, and in this way alters the voltage at the control input 32 dead time with respect to the voltage at the reference voltage input 30. Alternatively, more than one of the transistors 38-41 can be turned on.

A switch 53, such as a push-button switch for pressing, can be coupled to the clock input 37 and used to activate the counter 36. For example, by pressing the switch once, the clock of the counter 36 is started from the zero output to the first output, operating the switch a second time activates the counter clock 36 to a second output, and so on. As each output of the counter 36 becomes active, the transistor associated with said output turns on, altering the voltage of the dead time control input 32. In this way, the duty cycle of the driving signal from the P M controller 23 can be controlled gradually manually through various levels.

Figure 4 is a block diagram of a battery charger according to another embodiment of the present invention. The embodiment shown in Figure 4 includes a microprocessor that controls many of the functions of the battery charger. The general operating principles of the battery charger are the same as for the previous mode and are not discussed in detail here.

In this embodiment, a microprocessor 50 is coupled to the switches 22, 24 which, for example, comprises the FETs, and to the portion 8 of the high frequency transformer. A screen 52 is also coupled to the microprocessor 50. The screen 52 is used to display various diagnostic and output information regarding the battery charger. The user controls for turning on and off the battery charger, as well as the selectors 26, 30 (see Figure 1) and the button switch 23 for pressing (Figure 3) to control the operation of the battery charger in the battery mode. stages can also be coupled to the microprocessor 50.

The microprocessor 50 can be programmed to perform essentially all of the control functions necessary for operation of the battery charger. For example, the microprocessor 50 can be programmed to control the charging procedure. When the load / pulse selector 30 is pressed to select the charging mode, the microprocessor 50 receives this selection and controls the charging operation of the battery. This can be carried out using the well-known delta V or other loading technique known to those skilled in the art. When the charge / pulse switch 30 is operated to select the pulse mode, the microprocessor 50 receives this selection and controls the battery charger to perform the desulfurization process. The microprocessor 50 may also include a timer such that the battery charger automatically deactivates after a predetermined period of time.

The microprocessor 50 can also monitor the loading operation. By means of a feedback circuit described in the following or by some other means, the microprocessor 50 can monitor the voltage or the sensing that is supplied to the battery from the battery charger and the voltage or current of the battery and can detect shorts circuits or other failures, as described in more detail in the following. A resistive divider can be used to provide the voltage and current measurements to the A / D input of the microprocessor. A visual or auditory indication of the faults is provided, for example on the screen 52. A running message describes the fault, a representative code or another message may be presented. The microprocessor 50 can also be programmed to control the current pulse width modulation function. In this case, the PWM controllers 23 and 25 (Figure 1) can be removed and their functionality can be incorporated into the microprocessor 50.

In a further embodiment, the circuit shown in Figure 4 may include a logical setting that allows the high frequency charger to provide the power supply 56. The power supply 56 can be accessed by means of a typical cigar plug-in power adapter that is provided in the battery charger.

The embodiments shown in Figures 1 and 4 can alternatively be implemented by incorporating the apparatus of Figure 9 to implement the portion 8 of the high frequency transformer. Figure 9 shows the use of a single high frequency transformer 18 'to implement the two high frequency transformers 14 and 18. The switching circuits 22 and 24 are connected to different contacts (18c 'and 18b', respectively) on the primary side of the transformer 18 '. The pole 18a 'of the transformer 18' is coupled to the DC current source formed by the components 2, 4 and 6 of FIGS. 1 and 4. As shown, the switching circuit 24 controls a contact 18c ', which corresponds to a winding implemented by the transformer 14 of the charging circuit 12, while the circuit 22 controls a contact 18b 'corresponding to a winding that implements the transformer 18 of the reinforcing circuit 16. This last winding necessarily produces the high current output that is needed to provide the boost function. Filter rectifiers and capacitors 19 'replace components 19 and 20 of FIGS. 1 and 4. The other components of the apparatus are as shown in FIGS. 1 and 4.

Figure 4 also illustrates a feedback loop that can be provided to prevent the battery from overcharging. The feedback loop ensures that the appropriate amount of current is supplied to the battery. An opto-isolator 58 is coupled between the microprocessor 50 and the battery 21 which is charged and provides information regarding the process of charging the battery to the microprocessor.

Additional circuitry may also be provided for protection in terms of polarity and short circuits, as shown in the embodiment of FIG. 5. FIG. 5 is a partial schematic diagram of a battery charger showing only the elements of short circuit and polarity protection to simplify the compression of this modality. The other elements of the battery charger can be included, as shown in figures 1, 3 and 4.

In this embodiment, the battery charger is provided with a polarity detection circuit. Only when the polarity detection circuit detects that the battery is connected to the battery charger with the correct polarity, supplies power to the battery. Typically, the battery charger includes a pair of clamps 60, 61 for connection to the positive terminal and the negative terminal, respectively, of the battery to be charged 21. A polarity detection circuit detects the polarity of the battery connection. the clamps 60, 61 and provides a signal to the microprocessor 50. In response to the signal from the polarity detection circuit, the microprocessor controls the operation of the battery charger to supply power to the battery 21 or to indicate an incorrect polarity, when that is the case.

In the embodiment illustrated in Figure 5, the polarity detection circuit includes an opto-isolator 62 connected to the clamps 60, 61 and the microprocessor 50. The opto-isolator includes a light emitting diode (LED) 63 and a phototransistor 65. When the battery 21 is connected with the correct polarity, the clamp 60 is connected to the positive terminal and the clamp 61 is connected to the negative terminal of the battery 21. The LED 63 is then deflected forward and turns on the phototransistor 65. When the phototransistor 65 is turned on, it provides a logic high signal to a leg a4 of the microprocessor 50. The high logic signal indicates to the microprocessor 50 that the correct polarity connection has been made. The clamp 60 connecting the negative terminal of the battery 21 reverses the polarities of the LED 63 and no signal is provided to the microprocessor 50.

In response to the high logic signal, the microprocessor 50 transmits a control signal to a control circuit to complete the connection between the battery charger and the battery 21. Here, the control circuit includes a transistor 72 coupled between one of the clamps 60, 61 and the charger circuit. The transistor 72 acts as a switch to connect the battery 21 to the charger circuit. Only when the switch 72 closes the transistor 69 will complete the connection between the battery charger and the battery 21. The opening and closing of the transistor 72 is controlled by means of the transistors 69 and 70. A control electrode of the transistor 69 receives the control signal from the microprocessor. When the control signal is received, the transistor 69 is turned on, which in turn turns on the transistor 70. The current flow through the transistor 70 activates a control electrode for the transistor 72 and turns on the transistor 72, completing the circuit between the charger circuit and the battery 21. Only when the control signal is provided to the transistor 69 is it possible for the transistor 72 to turn on.Once the correct polarity connection has been established, the transistor 72 can remain on even after the clips 60, 61 are disconnected from the battery 21. The clips disconnected in this manner still have power. Therefore, a means for detecting the presence of a battery in the clamps can be provided. The microprocessor 50 can be programmed to detect at which moment the clamps 60, 61 have been disconnected and, in response, the transistor 72 is turned off. A voltage divider consisting of the resistors 74 and 76 is provided for this purpose. voltage divides the voltage across the clamps 60, 61 and provides a portion of this voltage to the microprocessor 50. When the clamps are disconnected from the battery 21 the voltage across the clamps 60, 61 will be greatly increased. The voltage provided by the voltage divider will also be increased in a corresponding manner. When the voltage provided to the microprocessor 50 exceeds the selected amount, for example 18 volts, the microprocessor 50 detects that the clips 60, 61 have been disconnected and immediately turn off the transistors 69 and 70, which turn off the transistor 72. Various resistors, such as resistor 78, may also be included in the circuit.

According to another embodiment of the invention, the means for detecting the presence of a battery in the clamps can detect the presence of a current flowing through the clamps 60, 61 instead of, or in addition to the voltage across the clamps. tweezers. The presence of a current flowing through the clamps 60, 61 may indicate whether the clamps 60, 61 are connected to a battery. A current flowing through the clamps when they are connected to a battery and the lack of current can flow through the clamps when they are not connected to the battery. The microprocessor 50 is adapted to detect the current flowing through the clamps 60, 61. When no current is detected, the microprocessor 50 detects that the clamps 60, 61 have been disconnected and immediately turn off the transistors 69 and 70, which turn off the transistor 72.

The means for detecting the presence of a battery in the clamps can also be used to detect a battery in poor condition or a battery whose voltage is too low to be charged. Normally, even an exhausted battery has a certain voltage, usually about 3-5 volts. However, occasionally, a battery has no voltage because it is so discharged that the battery is completely exhausted. This type of battery can not be charged immediately, in case it can be charged. When the clips of the battery charger are connected to this type of battery, it is as if the battery charger is not connected to anything. Since the voltage of said battery is extremely low, the microprocessor 50 does not detect any voltage through the clamps. A failure indication is presented if an attempt is made to charge the battery. This type of fault will also occur if there is no connection or if a bad connection is made to the battery 21 and the charger is activated. When the fault occurs, the microprocessor 50 can be programmed to show a suggestion to the user that the battery must be reconditioned before attempting to charge it or to verify if the clamps 24 are connected to the battery.

In another embodiment of the invention, the microprocessor 50 is programmed to determine the available cold start amperage (CCA) of the battery 21. The CCA is the amount of energy exerted by a battery when a vehicle is started on a cold day. The definition of the Battery Council International (BCI) is the capacity or discharge load in amperes which a fully charged, new battery at -18 ° C (0 ° F) can supply for 30 seconds and maintain a voltage of 1.2 volts per cell or greater The CCA is determined in the described mode by connecting a resistor in parallel with a battery 21. The resistor must be connected for a short period of time so that it does not drain the battery. The voltage of the battery is determined at the moment under the load of the resistance. The lower the battery voltage, the lower the charge, and the lower the CCA of the battery. The microprocessor is programmed to relate the measured voltage to a CCA value. The CCA value can be displayed to the user.

Returning now to FIGS. 6 and 7, flow diagrams of a software program that can be used to control the operation of the microprocessor in accordance with an exemplary embodiment of the present invention are illustrated. At the start of the program, the battery charger is initialized, steps 100-108. The microprocessor checks the status of the various user controls that can be provided in the battery charger. These controls may include, for example, load / pulse selector 30, boost selector 26 and any other user control. The state of the input controls can be verified after a predetermined period of time has elapsed, for example 200 microseconds in order to allow the control signals to reach the microprocessor. During this initialization procedure and during the charging procedure, the microprocessor can detect various faults with the battery charger. For example, the battery charger can be provided with a temperature detector that can detect the temperature of the battery. If the temperature of the battery is above the prescribed temperature, the microprocessor determines that the battery has been overheated and inactive to the battery charger. A fault message may also be displayed on the screen 52 indicating the overheating condition. If the detected temperature is below the prescribed limit, then the loading process continues.

Subsequently, the microprocessor determines which of the operating modes (loaded, pulsed, reinforcement, etc.), has been selected, in steps 110-112. In the embodiment shown in Figures 6 and 7, the process for the charging mode and the battery conditioning mode are illustrated. If none of the available operating modes have been selected, the process returns to the initialization stage and checks the status of the input controls again.

Once the mode of operation is selected, said selection can be displayed to the user by means of the screen 52. For example, if the battery conditioning mode has been selected, this selection is shown to the user by means of the screen 52 , step 114. Then the battery conditioning mode is started. A timer is verified to determine if the battery charger has previously been in operation in the battery conditioning mode for a predetermined period of time. In this mode, it is verified if the battery charger has been operating in the battery conditioning mode for 24 hours. If the charger has been in operation in the battery conditioning mode for more than 24 hours, the battery conditioning process is complete and the process returns to the starting stage 102. If the battery conditioning procedure has been carried out for less than 24 hours, the battery conditioning process continues. The battery charger pulses the battery to perform the conditioning. The switching of the FET switch 22 is controlled to generate the conditioning pulses, steps 118-124. For example, the microprocessor can enable the PWM controller 23 to turn on and off the FET for a period of time, of approximately 50 microseconds. Subsequently, the PWM controller 23 is turned off, disabling the FET switch 22. The FET is not switched when the PWN controller 23 is off. PWN controller 23-26 - may remain off for approximately 1 second. The procedure then returns to step 114 and is repeated until the battery conditioning operation has been performed for 24 hours, at which time the battery conditioning procedure is completed.

When the microprocessor detects that the charging mode has been selected, the process proceeds to step 126. Here, the charging current that is supplied to the battery 21 is shown to the user by means of the display 52. The microprocessor detects if has completed the loading process. This can be done by verifying if an indication (flag) has been established that indicates that the loading process has been completed. If a full charge indication is established, the charger is turned off and a full charge indicator is activated, for example an LED to indicate to a user that the charge has been completed. The procedure then returns to the start stage and waits for additional instructions through user input, steps 128-132.

If the full charge indicator is not set, the process proceeds to step 134 (in figure 7) and detects if the battery is connected to the charger. This verification can prevent power from being supplied from the battery charger unless the battery is connected to the battery charger, avoiding a potentially dangerous situation. The means for detecting the presence of a battery in the clamps discussed in the foregoing in relation to Figure 5 can perform this verification. Additionally, the process for detecting a battery in poor condition or a battery having a voltage too low to be charged as described in the above can also be carried out at this time. If a bad battery, a battery with low voltage or the lack of a battery is detected, a fault indication is shown, and the carburetor can then be disabled in step 136, and the process returns to the initialization stage.

When a connection to a battery is detected, the microprocessor enables the PWM controller 23 to generate a driving signal for the FET switch 22, steps 138-142. If the loading process has already started, these steps can be skipped.

Then, it is determined whether the battery charger is operating in a bulk charging mode or an absorption charging mode. This determination is made by examining an indicator (flag) of absorption stage. If the absorption stage indicator (flag) is set, the battery is in the absorption charging mode and the process proceeds according to step 168. If the absorption stage indication is not established, the battery is still set. find in bulk loading mode. The process then proceeds to step 146 to continue the bulk loading mode and to determine at what time the bulk loading mode has been completed.

Additional failure checks can be made at this time to ensure that the loading operation proceeds correctly, steps 146-154. Failure verification can also be performed at other times during the procedure.The microprocessor can detect various faults, which include a battery with a short cell, a battery with an open cell and an excessive time allowed for the charging process, among other things Various measurement means are provided to measure the parameters required to supply this information to the microprocessor.

If a battery has a short cell, it is unlikely that the battery voltage will increase when you try to charge the battery. However, charging must be attempted for a certain period of time before it can be determined whether the battery has a short cell. The microprocessor can be programmed to monitor the voltage, current and charging time to detect a short cell. If the charging speed is greater than a predetermined current, the battery has been charged for a period greater than the predetermined amount of time and the battery voltage is less than or equal to a predetermined voltage, a shorted cell is detected. For example, if the battery charge rate is greater than 2 amps, the battery has been charged for more than 1 hour, and the battery voltage is less than or equal to approximately 11 volts, the charger is turned off and indicates to the user a short cell fault.

The process for detecting an open cell battery is similar to the process for detecting a short cell battery. An open cell battery has a certain voltage due to leakage between the open cell and its connectors. However, the open cell battery does not have the capacity to accept or supply current. When the battery charger is connected to an open cell battery, the microprocessor detects a voltage in the clips of the battery charger, but when the charging process starts, no appreciable current is detected. If no current is detected after a predetermined period of time, for example 5 minutes, an open cell battery is detected and the appropriate fault indication is displayed. If an open cell or a short cell is not detected, the process can proceed to step 156.

Step 156 determines whether the battery has been charged for an extended period of time, and if the charging process is not complete yet, an excessive time fault is declared. There may be situations where the battery voltage increases during charging, in contrast to a short-cell battery, but the battery is not fully charged within the predetermined time period. This can happen, for example, in a very large battery which is charged at a very low current speed. A battery with 100 amps per hour can not be charged with a speed of 2 amps in a reasonable amount of time. Therefore, the loading speed is too low to finish loading in a reasonable period of time and a failure is indicated. Additionally, another type of failure mode in a battery can cause the same circumstance, that is, a battery with a serious internal leak.

An excessive time fault occurs if a predetermined voltage is not reached within a predetermined period of time, although the current is still flowing. When these conditions are satisfied, an excessive time fault is indicated on the screen. For example, with reference to steps 150-156 of Figure 6, it is determined whether the battery has been charged for more than 18 hours. If so, the battery has been charged for a substantial period of time, although the battery voltage is not above 12 volts, by step 150. In this way, a fault is detected and the process advances to the step 152, where the charger is turned off, and after step 154, where a fault is indicated. - 29 - If the battery has not been charged for 18 hours, the process continues with step 158. Step 158 uses feedback from the battery to adjust the duty cycle of the signal that activates the FET 22. If the current is provided from the Battery charger is greater than or equal to the desired current, the duty cycle of the driving signal decreases, step 160. If the current current is less than the desired current, then the duty cycle of the driving signal is increased, step 162 Next, it is determined whether the battery voltage is greater than or equal to a predetermined voltage, for example 14 volts, for at least a predetermined period of time, for example, 2 seconds, step 164. If the battery voltage does not has been greater than or equal to 14 volts for at least 2 seconds, the procedure returns to the initialization stage. On the other hand, if the battery voltage has been greater than or equal to 14 volts for more than 2 seconds and the battery has not been charged for a predetermined time, for example 15 hours (step 166), a fault is indicated, and the process advances to steps 152 and 154. Otherwise, the process advances to stage 200 and an indicator is established for the absorption stage. The process then returns to the start stage and starts again.

If an absorption stage indication has been established, the process proceeds from step 144 to step 168. If the battery voltage is greater than or equal to a predetermined voltage, for example 14 volts, the duty cycle of the driving signal is decreased. If the voltage is less than 14 volts, the duty cycle of the driving signal is increased, steps 168-172. Subsequently, it is determined if the battery current is greater than or equal to the bulk charge current. If the current is greater than or equal to the bulk loading current, the duty cycle of the driving signal decreases, otherwise no changes are made to the duty cycle, steps 174-176. A check is then made to determine if the absorption charge mode is complete. If the battery voltage is greater than or equal to a predetermined voltage, for example 14 volts, and the battery has been charged for a predetermined time, for example 2 hours, the absorption charge mode is complete and an indicator is set of full load, stages 178-200. The loading process is complete and the process returns to the start stage and awaits additional instructions.

The microprocessor 50 can also be used to carry out a test of an alternator of a vehicle with a spent battery. When the vehicle alternator is functioning properly, the voltage level of the discharged battery 21 increases rapidly shortly after the battery has started to operate. The rapid increase in voltage can be detected by the microprocessor 50 based on the signals received by the microprocessor of the opto-isolator circuit 62. If a rapid increase in voltage is detected, a message that the alternator is functioning properly can be displayed on the screen 52. If a rapid increase in voltage is not detected, then a message indicating malfunction of the alternator may be displayed on the screen 52. The rapid increase in voltage may vary depending on how exhausted the battery is. The microprocessor can be programmed to take this variation into consideration.

Another fault that can be detected by the microprocessor is an overheated charger. The charger may overheat due to limited air flow or internal fault. A temperature detector that measures the internal temperature of the charger can be attached to the microprocessor. When the microprocessor detects that the temperature of the internal electronic circuits of the battery charger is too high, a fault is detected and is displayed on the screen 52.

In a further embodiment of the invention there is provided a method for electrically testing a connection between the battery charger and the battery to be charged. The method allows this connection to be tested before high current levels can result in sparks or arcs being available. According to this embodiment, a current amount less than the total available charge current is initially provided from the battery charger. It is then determined whether a smaller amount of current is present in the battery to be charged. If so, the current level provided from the battery charger is gradually increased, for example, gradually or in accordance with a successive change function. The current provided from the battery charger is checked in various increments to determine if the current provided from the battery charger is present in the battery being charged. If the current from the battery charger is present in the battery that is charged, the current increase continues until the desired charging current is reached. If, at any point during the current increase, the current from the battery charger is not present in the battery that is charged, one can be detected. failure. When a fault is detected, the current from the battery charger can be reduced to a lower level and safer that it does not produce a spark or arc.

In Figure 8 a flow chart is illustrated in relation to this embodiment in the invention. First, the battery charger is coupled to the battery that is charged, in step 202. The battery charger may have an available output current of about 6 amps, for example. Initially a much smaller current, for example 0.5 amps, is provided from the battery charger as a test current, step 204. In step 206, a test is performed to detect the presence of the 0.5 amp test current in the battery that is charged. If the test current is not detected, a fault is indicated and the charging process is stopped, in step 208. In step 210, it is determined whether the current is equal to the desired charging current. If so, charging continues to the desired charging current, step 212. Otherwise, the process proceeds to step 214. In this case, the 0.5 amp test current is present in the battery that is charged, and the current that is provided from the battery charger is increased to the next level, for example 0.75 amps. The process then returns to step 206 to detect the increased current. The battery has been provided with a gradual or successive increase in current in this manner which detects a failed connection between the battery charger and the battery that is charged before the high currents can produce sparks. The microprocessor can be programmed to operate the battery charger in this way. - 32 - Accordingly, a high frequency charger and a method for operating a high frequency charger are provided. The use of high frequency transformers provides several advantages. For example, with respect to the switching frequency which is sufficiently high, no iron is needed for the core of the transformers. A very light substance, for example ferrite, can be used, which greatly reduces the weight and unmanageability of the known devices. Additionally, the secondary winding of the transformers can have a small number of windings, for example as few as four turns of wire. In comparison, a conventional transformer may require more than 100 turns of wire. The higher the frequency, the smaller the wire needed, which further reduces the costs required to manufacture the device.

The embodiments illustrated and discussed in this specification are designed solely to show those skilled in the art the best way known to the inventors to produce and use the invention. Nothing in this specification should be considered as limiting the scope of the present invention. The embodiments described in the foregoing of the invention can be modified or varied and elements added or deleted, without departing from the invention, as will be appreciated by those skilled in the art based on the foregoing teachings. Therefore, it should be understood that, within the scope of the claims and their equivalents, the invention may be practiced in a manner other than that specifically described. For example, the processes described in the above can be carried out in a different order from that described above.

Claims (43)

1. A high frequency charger, characterized in that it comprises: a single high frequency transformer; a switch configuration for switching to a single high-frequency transformer to produce a charging current for charging a battery and for switching the single high-frequency transformer to produce a relatively high boost current as compared to the charging current; and a controller that provides a high frequency drive signal to the switch configuration.

2. The high frequency charger in accordance with the claim 1, characterized in that it further comprises a enabling circuit that selectively enables and disables the controller at a predetermined speed to produce a series of DC pulses as the DC output signal.

3. The high frequency charger in accordance with the claim 2, characterized in that the series of pulses has an increase time of less than 100 volts per microseconds.

4. The high frequency charger according to claim 2, characterized in that the series of pulses has a frequency of about one pulse per second.

5. The high frequency charger according to claim 1, characterized in that the reinforcement current from the single high frequency transformer has a current of about 30-300 amperes.

6. The high frequency charger according to claim 1, characterized in that the reinforcement current from the single high frequency transformer has a current of approximately 60-300 amperes. - 3. 4 -

7. The high frequency charger according to claim 1, characterized in that the charging current from the high frequency transformer has a current of approximately 2-20 amps.

8. The high frequency charger according to claim 1, characterized in that the charging current from the high frequency transformer has a current of about 2-15 amps.

9. The high frequency charger according to claim 1, characterized in that the charging current has a current of about 2-15 amps and the reinforcing current has a current of about 60-300 amperes.

10. The high-frequency charger according to claim 1, characterized in that the charging current has a current of approximately 2-20 amperes and the reinforcing current has a current of approximately 60-300 amperes.

11. The high frequency charger according to claim 1, characterized in that the charging current has a current of about 2-15 amps and the reinforcing current has a current of about 30-300 amperes.

12. The high frequency charger according to claim 1, characterized in that the charging current has a current of about 2-20 amperes and the reinforcing current has a current of about 30-300 amperes.

13. The high-frequency charger according to claim 1, characterized in that the reinforcement current from a single-frequency high-frequency transformer has a duration of about 3-35 seconds.

14. The high frequency charger according to claim 1, characterized in that it further comprises: connectors for coupling an output of the single high frequency transformer to the battery; circuit coupled to the connectors and operative to detect a failure with the battery; and a screen to indicate the detected fault.

15. The high frequency charger according to claim 14, characterized in that the fault includes at least one of the excessive time fault, a short cell fault, a bad battery failure, and an open cell fault.

16. The high frequency charger according to claim 14, characterized in that it further comprises a polarity protection circuit to allow current to flow through the connectors and to the battery only when the connectors are coupled to the battery with a correct polarity.

17. The high frequency charger according to claim 16, characterized in that the polarity protection circuit is coupled to the connectors to determine a polarity between the connectors and provides a polarity signal; and further comprising a switch coupled to at least one of the connectors and opening or closing depending on the polarity signal.

18. The high frequency charger according to claim 14, characterized in that it further comprises an alternator tester coupled to the connectors and to produce an alternator fault signal as a function of the voltage. - 36 -

19. The high frequency charger according to claim 18, characterized in that the alternator tester further comprises: operational circuitry to detect a rapid increase in voltage after a vehicle has been started with a battery and a fault signal has occurred of alternator in the absence of a rapid increase in voltage; and wherein the screen is coupled to the circuitry to provide an indication that the vehicle alternator is not functioning properly in response to the alternator fault signal.

20. The high frequency charger according to claim 14, characterized in that it also comprises circuitry coupled to the connectors and operative to desulphrate the battery.

21. A high frequency charger characterized in that it comprises: a high frequency transformer; a switch configuration for switching the high frequency transformer to produce a charging current for charging a battery and for switching the high frequency transformer to produce a relatively high boost current as compared to the charging current; and a controller that provides a high frequency drive signal to the switch configuration, wherein the boost current is sufficient to start a vehicle.

22. The high frequency charger according to claim 21, characterized in that the controller provides a pulse width modulated driving signal.

23. The high-frequency charger according to claim 21, characterized in that it further comprises measurement circuitry for measuring at least one of a voltage or a current in the battery.

24. The high frequency charger according to claim 23, characterized in that it further comprises a computer coupled to the measurement circuit to calculate at least one diagnosis based on at least one of the measured voltage or current.

25. The high frequency charger according to claim 21, characterized in that it further comprises a selector switch coupled to the controller to select one of: (1) a charging mode in which the high frequency transformer is switched to produce the charging current , and (2) a reinforcement mode in which the high frequency transformer is switched to produce the reinforcing current.

26. The high frequency charger according to claim 21, characterized in that the controller comprises: a first means for providing the driving signal to the switch configuration; and a second means for selectively enabling and disabling the first means, whereby the charging current comprises a series of DC pulses.

27. The high frequency charger according to claim 21, characterized in that it further comprises a microprocessor coupled to the controller to control the controller to provide the driving signal to the switch of the switching configuration to produce the charging current or the relatively high boost current. .

28. The high frequency charger according to claim 23, characterized in that it comprises: a processor coupled to the measurement circuit to perform an alternator test to detect an indication of alternator operation in dependence on at least the voltage in the battery; and a screen coupled to the processor to indicate at least one of the - 38 - battery voltage and indication of the operation of the detected alternator.

29. The high frequency charger according to claim 23, characterized in that the controller is coupled to the measurement circuitry and provides a high frequency driving signal to the switch based on at least one of the voltage and current in the battery.

30. The high frequency charger according to claim 21, characterized in that it further comprises a microprocessor coupled to the controller to selectively enable and inhibit the controller to produce the driving signal.

31. The high frequency charger according to claim 21, characterized in that it further comprises a microprocessor coupled to the controller to control the control to vary a duty cycle of the driving signal.

32. A high frequency battery charger for charging a battery, characterized in that it comprises: a charger circuit that includes a high frequency transformer, a switch that switches to the high frequency transformer, a filter coupled to the high frequency transformer to pass a signal DC voltage and a controller that provides a high frequency drive signal to the switch; measurement circuitry for measuring at least one of the voltage or current of the target battery; and a microprocessor that receives the measured voltage or current and calculates the diagnosis of the target battery based on at least one of the measured voltage or current.

33. The charger according to claim 32, characterized in that it further comprises connectors coupled to the charger circuit and adapted to be connected to the target battery to provide the DC voltage signal to the target battery, the measurement circuit is coupled to the connectors for measuring at least one of the voltage or current.

34. The charger according to claim 32, characterized in that the diagnosis includes at least one of an excessive time fault, a short cell fault, a bad battery failure or an open cell fault.

35. A method, characterized in that it comprises: producing both a charging current and a boost current for a battery using a high frequency switch of a DC power source through a high frequency transformer; supplying one or both of the charging and reinforcing currents to a battery, wherein the reinforcing current is relatively greater than the charging current and is sufficient to start a vehicle containing the battery.

36. The method according to claim 35, characterized in that the reinforcing current is in a range of about 30 amperes to about 300 amperes.

37. The method according to claim 35, characterized in that the reinforcing current is in a range of about 60 amperes to about 300 amperes.

38. The method according to claim 35, characterized in that the charging current has a current of approximately 2-20 amps.

39. The method according to claim 35, characterized in that the charging current has a current of about 2-15 amps. - 40 -

40. The method according to claim 35, characterized in that the charging current has a current of about 2-15 amps and the reinforcing current has a current of about 60-300 amperes.

41. The method according to claim 35, characterized in that the charging current has a current of approximately 2-20 amperes and the reinforcing current has a current of approximately 60-300 amperes.

42. The method according to claim 35, characterized in that the charging current has a current of about 2-15 amps and the reinforcing current has a current of about 30-300 amperes.

43. The method according to claim 35, characterized in that the charging current has a current of approximately 2-20 amperes and the reinforcing current has a current of approximately 30-300 amperes.