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 any people, when first
hearing about Chorus® motor technology, have questions about what it is, how it works,
and what it means for the world of electric motors. Whether an expert or an amateur in
the field, this page should address many of those concerns.If you have a question that is not answered here or elsewhere on our site, please feel free to contact us, or send an e-mail to pr@chorusmotors.gi. The Basics Q - First, what should I know about electric motors to understand what is important about the Chorus motor? A - Most AC induction motors now in use are 3-phase ("polyphase") machines. Each phase acts at a different angle from the others, so they work together to turn the rotor of the motor. Along with the main wave pattern (called "the fundamental"), there are accompanying repetitive complex waveforms called "harmonics". In a conventional electric motor, these harmonics act as a brake on the main wave. Harmonics slow down conventional electric motors and they limit the amount of power a motor can efficiently use to generate rotational force (called "torque"). Q - What is so special about the Chorus motor? A - The principal technical advance of the Chorus technology is that harmonics are co-opted and enlisted to act in concert with the fundamental. Instead of acting like a brake as in the conventional 3-phase motor, the harmonics are now used to drive the Chorus motor alongside the fundamental frequency. The most stunning breakthrough of the Chorus technology is that it changes what was a braking force into an additional driving force. Heat produced by an electric motor is energy that was not efficiently converted into motion. Efficiency and heating problems tend to set the limits of continuous power output on a variable frequency drive. The new Chorus motor is much more efficient, and produces less heat, than a variable frequency drive; and can have a commensurately higher continuous torque output. Furthermore, for short time periods, a Chorus motor provides 3 to 5 times the peak torque of a conventional drive. Peak torques are used when motors require extra power for short amounts of time for things like starting and stopping, or adjusting rapidly to changes in load. Q - Let's say I'm not familiar with electric motors; is this a relatively minor improvement? How does it relate to electric motor technology overall? A - Unlike most "new motor technologies," Chorus technology is a breakthrough. Electric motors are considered a mature technology which has already been heavily researched for decades; only small incremental improvements are expected. Efforts at solving the problems posed by the harmonics generated by motors and electronics have been made throughout the years and during that time the careers of very talented people have come and gone. The accepted conclusion has become "If it hasn't been done by now, it probably can't be done." Borealis has revisited electric motor technology and developed the Chorus motor for co-opting harmonics and using them to drive the motor. This breakthrough contrasts with existing motor technology which seeks to eliminate, reduce, or at least nullify harmonics. These previous approaches, while valid, tend to be more expensive and they cause the conventional motor to output much less power than is possible with a Chorus motor. Borealis' first Chorus technology patent was issued April 25, 2000, and several more patents have since been issued. A working 18-phase prototype demonstrates the advantages of the technology in head-to-head tests against standard 3-phase motors. Q - Does the Chorus drive have peak torque advantages? A - Operating the Chorus drive with a square wave drive results in a greater RMS voltage output from the inverter for the same DC link voltage. This means that the motor will be operated at a higher voltage and a correspondingly lower current, enabling the same power electronics to provide greater motor power at a fixed DC link voltage. This higher power may either be in the form of increased constant torque speed, or if the motor is wound with a greater number of turns, greater peak torque capability. Q - What would be the continuous torque rating? A - The motor continuous torque rating is set by heating and thus slot current; if the number of turns is increased then smaller wire would need to be used, and while the inverter would thus be capable of greater overload torque, the motor would have essentially unchanged continuous torque. Furthermore, the Chorus motor design makes better use of slot copper. In a conventional 3-phase machine, individual slots carry halves of two separate windings, often windings from different phases. The net result is that the RMS slot current is not simply the RMS winding current times the number of turns, but something less than this. A Chorus drive provides greater net slot current for the same winding current, resulting in greater MMF for the same copper losses, and thus greater efficiency. For the same RMS applied voltage, Chorus motor windings have fewer series turns for reduced copper losses. In summary, a Chorus drive offers higher efficiency, smaller size and weight, very high startup torques, greater continuous torque, and greater reliability. Q - Is it robust? A - In a normal 3-phase motor, failure of a single phase means the motor cannot start itself. Damage to a single phase in a multi-phase Chorus drive will only slightly reduce efficiency; this is another major improvement over conventional 3-phase AC motors. Implementation Questions Q - Does a Chorus drive cost more to manufacture? A - A smaller Chorus drive is cheaper to manufacture and has no commutator or brushes, which reduces maintenance. Normal fixed-frequency and variable-frequency motors can be rewound and on new motors, cheaper switches (SCRs, MOSFETs, or slower IGBTs) can be installed. Q - Do the power electronics cost more? A - A drive has two components, the motor itself, and the electronics which produce the control signals and synthesize the waves. The electronics are usually more expensive than the motor itself (at all drive sizes). Conventional drives use IGBTs (Insulated Gate Bipolar Transistor) for the electronics, which are faster switching elements (fast switching means fewer harmonics). For the same continuous capacity, IGBTs cost triple the price of SCRs with the same current capacity. SCRs- (Silicon-Controlled Rectifiers) produce a great deal of harmonics and makes them detrimental in a normal motor which is why SCRs have been largely replaced by IGBTs. By now you may already know where this is going. Chorus technology uses much older, more rugged, and far simpler SCRs since Chorus technology uses harmonics beneficially. Furthermore, SCRs are much more rugged than IGBTs, with 3x the overload current of IGBTs for the same continuous rating. So for momentary high torque applications, Chorus motor electronics will cost 1/9th that of the competition to manufacture. In the near term, Chorus motors are expected to use IGBTs as well; they are flexible and powerful devices. But because of other advantages, Chorus motors extract significantly more power from a given IGBT than a 3-phase motor can. Q - What about high speeds? A - The Chorus technology design is tolerant of harmonics. At high speed, an inverter will be forced to either operate at an extremely high switching frequency in order to develop a sinusoidal output, or the output will have substantial harmonic content. 100,000 RPM corresponds to 1.667 kHz; which is the order of the switching frequency normally used in inverters. However, to produce good sine waves, an inverter would need to operate in the 30-50 kHz or above range, with tremendous switching losses. This means that, all other things being equal, a Chorus drive will operate with lower inverter losses since a Chorus drive could operate with the inverter switching frequency the same as the output frequency. Q - What about low speed operation? A - The Chorus technology offers two solutions to the problem of low frequency operation. At very low drive frequencies, inverters suffer from a reduction in RMS current capability. This is caused by the time constants associated with conduction loss heating of the switching elements. At moderate frequencies, the heating experienced by the switching elements is related to the RMS current flow through these elements. At low drive frequencies, the switching elements will heat up and cool down as they each in turn conduct the drive current. This means that at low frequencies, the temperature rise of the switching elements is related to the peak current flow, and in order to suitably limit temperature rise, the peak current must be limited with corresponding reduction in RMS current. The first solution Chorus technology offers is that the pole changing capability of the machine may be used to maintain drive frequency even as synchronous speed is reduced. The second solution is to operate with square wave current flow. In this case the RMS current and the peak current are the same, and therefore there is no reduction in RMS current capability at low frequencies. A Chorus drive's ability to operate with high harmonic content may also have value in the high speed regime, where it will allow greater RMS voltage to be synthesized from the same DC rail voltage. This is similar to a technique used in 3-phase inverter systems, wherein a suitable amount of third harmonic component can be used to boost the output voltage. Q - Is there any other advantage at low speed operation? A - A Chorus motor, with its harmonic tolerance, can be operated at low speed with a square wave drive waveform, permitting greater RMS current to flow into the machine from the same power electronics, thereby increasing the power output of a given amount of power silicon. However, there is another engineering tradeoff that Chorus technology enables. When we speak about overload current, what we are really speaking of is the slot current. In a motor, you have many turns of wire, all sitting in parallel in the slots. The current in the wire, multiplied by the number of times the wire goes through a slot, gives the slot current. When we change the number of turns, we change two things: the amount of wire current needed to get a particular slot current, and the voltage needed to get this wire current. For example, if you double the number of turns, then for the same slot current you get to use half the wire current, but you need twice the voltage; power stays the same, since it is the product of voltage and current, but the relationship between the two is changed. All this comes down to matching the motor to its power supply. It is quite common to arrange 3-phase motors with several ways to connect the windings, so that various windings can be put electrically in series or parallel, so that the motor can operate at either 240 or 480 volts. With the lower voltage connection, one has to supply more current to the machine. When a motor is operated on an inverter, the output frequency and voltage are variable. One could, for example, take a motor wound to operate at 240 volts, and connect it to an inverter that was further connected to a 480-volt supply. The inverter would be capable of supplying the correct voltage. However, the lower voltage motor would require greater current; and in general, the inverter will have a maximum current which it could supply. So to provide the best low speed operation, you want a motor with lots of series turns; this will in turn reduce the current that the inverter needs to supply, and permit the inverter to provide greater slot current. However, increasing the number of turns increases the motor operational voltage. Since the inverter will also have a maximum output voltage, increasing the number of turns in the motor will degrade the high-speed performance of the drive system. In a variable voltage/variable frequency drive system, the voltage which the inverter must supply to the motor scales with speed. This means that at low speed, the output voltage needed is lower than at high speed. It yields an interesting result: changing the number of turns in the motor doesn't cause the machine to stop functioning, instead it changes the speed at which the motor operates at the maximum voltage of the inverter. If you increase the number of turns, then the inverter will reach its maximum voltage at lower speed. So what happens when we increase the number of turns? The inverter limited wire current stays the same; thus, the inverter limited slot current is increased. We can thus get move overload torque out of the motor. However, the maximum inverter voltage is reached at a lower speed; the motor is restricted to operating at lower speed, and thus has less motor limited power output. In the ideal case, the power output of both the motor and the inverter are matched to the load, so that the motor can provide sufficient low speed torque, and the inverter can provide sufficient voltage to operate at the desired high speed. A Chorus drive can expand this operational envelope. Previously mentioned is the fact that this technology will permit the use of square wave current flow in the motor, which would increase the power output of a given amount of power silicon by increasing the RMS current flow for a given peak current flow. If, however, we posit that this is not the case, and that the current carried in the Chorus inverter will be the same as that carried in a conventional inverter, there is still another means by which a Chorus drive allows us to get more power output out of a given inverter. The maximum voltage which an inverter can produce is set by the DC link voltage; this sets the peak amplitude of the output waveform. If a pure sine wave is synthesized, then the RMS voltage of this sine wave is directly related to this peak value. The use of harmonics allows this relationship to be changed. A known trick with 3-phase machines is to selectively add the third harmonic to the output waveform. By adding a suitable third harmonic to a waveform, the peak amplitude of the waveform can be reduced, all the while maintaining the exact same fundamental amplitude. The third harmonic doesn't actually flow into the machine; so the machine itself sees unchanged fundamental. By selectively adding a third harmonic to a waveform, the peak fundamental output voltage for a given DC link voltage may be increased. This means that with the same inverter and DC link voltage, we get to operate the motor at higher speed. On the other side of the coin, we could take the motor, and increase its turn count, thus keeping the same inverter limited maximum speed, but increasing the low speed torque. This same sort of technique can be used with a Chorus drive, but instead of adding third harmonic, we can add a large number of harmonics. In the limit, we can feed the motor with voltage square waves for high-speed operation. The fundamental component of a square wave of given peak amplitude is about 27% greater than the fundamental component of a sine wave of the same peak amplitude. This essentially means that we could increase the motor turn count by 27%, while keeping the same "base speed" (the speed at which the machine reaches maximum inverter voltage) with the same DC link voltage. This increase in turn count won't change the continuous capability of the machine, but the inverter limited overload slot current of the machine will essentially be increased by 27%. This improvement in inverter utilization at low speed is entirely in addition to any benefit obtained from square wave current drive. Additionally, with PWM techniques, we are not limited to operating with pure square waves; square wave operation could be used at high speeds, with sinusoidal excitation used at low speeds, or some other operational mix. Q - What about electronic interference? A - The lower frequency switching will permit the use of lower speed switching elements, which means reduced EMI. Additionally, the 'distribution' of switching events across phases means reduced peak amplitude of any produced EMI. Q - Is the Chorus technology a new electronic solution to the old harmonic problem? Do I just replace the electronics? A - No, the windings are also proprietary. Existing fixed-frequency and variable-frequency motors can be rewound and refitted with new electronics to become a Chorus drive. How Chorus Technology Works Q - How about giving me a more technical explanation? A - A Chorus drive is a high phase order induction machine. The stator has extensive pole changing capabilities, which allows the stator to generate any 4n+2 or 4n number of poles up to the slot count, with certain machine symmetry limitations. Because of induction machine scaling laws, the pure pole changing capability is of limited usefulness, higher pole count machines have smaller poles, and thus have greater magnetization losses. The primary benefit of the pole changing capability is that the drive phase relationships used to produce the pole changing effect are precisely the same phase relationships found between the harmonic components of the drive waveform. If one considers the drive waveform to be the desired fundamental with superimposed harmonics, one finds that the rotating field produced consists of the desired base pole count with superimposed higher pole count rotating fields. In contrast to a conventional 3-phase machine, these harmonic rotating fields rotate in synchronism with the desired fundamental rotating field. The efficiency loss associated with harmonics in the drive waveform is thus greatly reduced, and various engineering compromises made in order to reduce harmonic content may now be shifted in the direction of increased harmonic content. For example, the PWM base frequency may be substantially reduced. Q - What is the difference in the use of harmonics between a Chorus motor and a conventional 3-phase motor? A - The effect of harmonics on 3-phase machines is well known. Harmonic components in the drive waveform produce rotating magnetic fields that are superimposed upon the fundamental rotating field. The fundamental rotating field essentially swamps the harmonic components, but each component has its effect on machine output. For example, any fifth harmonic component in the drive waveform will produce a rotating field with the same pole count as that of the fundamental, but rotating in the reverse direction at five times the speed of the fundamental. A slight amount of fifth harmonic content in the drive feeding a 3-phase machine will cause substantial losses, a noticeable reduction in efficiency, and an increase in machine heating. In the Chorus technology, the rotating fields produced by the harmonics of any reasonable drive waveform are similarly swamped by those of the fundamental, with the exception of intentional pole changing. These harmonics are superimposed upon the fundamental rotating field, just as in the 3-phase case. The difference is that these harmonic rotating fields are rotating in synchronism with that of the fundamental. This means that a slight amount of fifth harmonic content in the drive feeding a Chorus motor will cause only a slight change in total machine efficiency. In a 3-phase machine, any harmonic content will result in essentially pure losses; whereas in a Chorus motor they produce useful output, with reduced efficiency relative to that of the fundamental. Q - What about Chorus motor overload performance? A - The Chorus technology design allows for substantially greater overload capabilities than conventional 3-phase machines. These overload capabilities allow, for example, for a compressor to be started against a load, as in a hot restart situation. The Chorus drive's overload capabilities are essentially open ended, and are thus inverter limited. It is well known that greater performance can be obtained from a rotating machine by increasing the magnetic flux density threading the machine. In the case of induction machines, just increase the terminal voltage. The breakdown torque of an induction machine scales as the square of the terminal voltage. However, when operating at increased terminal voltage, several things start to happen: the machine iron begins to saturate (which will directly increase losses), and the impedance of the machine will become extremely non-linear. Current flow will cease to be sinusoidal, even if the power supply maintains a pure sinusoidal voltage output. Finally, no-load current will increase, causing increased losses. For these and other reasons, conventional induction machines are not operated in the heavily saturated regime. Many of the loss terms associated with operating at high saturation levels are associated with harmonics caused by the non-linear response of the machine to saturation. Not only are there direct increases in various losses, but also as saturation is increased there is a general increase in non-synchronous torques. These harmonic loss terms can greatly degrade machine performance when operating at high saturation levels. The Chorus drive's tolerance of harmonics means that the machine can be operated at much higher saturation levels for extreme overloads; additionally moderate increases in terminal voltage and saturation levels may be used for continuous operation. The Chorus technology has been demonstrated with short term locked rotor torque of greater than ten times the continuous rated torque. Q - Are there any inverter efficiency improvements? A - All inverter design requires a certain amount of compromise. From the point of view of the motor, the ideal inverter would have a linear output, meaning that voltage and current would smoothly vary. However, linear control elements are inherently inefficient, and must be so; they act like variable resistors, and must therefore dissipate power while operating. The first compromise made in inverter design is the use of switch mode control elements. Switch mode control elements are either on, with minimized conduction losses, or off, with minimized losses because they aren't carrying any current. The higher the switching frequency, the greater the fidelity of the inverter output. However, higher switching frequency also entails greater switching losses, produces greater EMI, and may also place greater stresses on the motor winding itself. Higher speed control elements also tend to be more expensive, and have greater conduction losses. The Chorus technology, with its increased harmonic tolerance, permits operation with lower switching speeds. At the extreme end of this performance scale, A Chorus drive may be operated efficiently using autocommutated SCR type inverters, which supply either six-step voltage or six step current waveforms to the machine. SCR based inverters generally have switching speeds which are the same as the output frequency; and for a given current capacity SCR control elements are less expensive than bipolar or IGBT control elements, however the commutation control can be complex. In any case, inverters used with a Chorus drive will tend to use much lower switching speeds than is currently considered state of the art with 3-phase systems, and lead to efficiency improvements. Q - How does the pole changing work? A - The 120-degree phase relation is so deeply ingrained in the art as to have become gospel. Motors are wound with 3-phase windings that are positioned to evenly divide each pole into three sections. Nevertheless, 3-phase winding is not essential to induction motor operation. The transition to 3-phase power distribution from 2-phase power distribution was driven by the fact that both 3-phase and 2-phase power distribution require three wires; 2-phase power distribution is essentially imbalanced 3-phase power. The only requirement for the proper drive of a polyphase induction motor is that the phase difference between the currents feeding each pole/phase group be the same as the magnetic angle separating the pole/phase groups. In an example machine with 30 slots symmetrically arranged, and 2 poles, with single slot pole/phase groups, each pole/phase group is separated from the adjacent pole/phase by 12 degrees. The electrical angle between slots is thus simply 12 degrees. In a practical machine, windings which each fill two slots would be used, and in a star connection every other slot would be driven, thus the electrical angle between phases is 24 degrees. While the phase angle of the currents driving a slot must be in fixed relation to the magnetic field structure being generated, the electrical angle between slots is not fixed. If one changes the phase angle of the currents driving the various slots, then a different magnetic field structure will be produced. Several different phase relations will result in balanced polyphase drive of the machine. For example, using the same 30 slot machine, with 24 degrees between adjacent driven slots, if the electrical angle between adjacent phases were changed to be 72 degrees, we would obtain a rather interesting result. While traversing the stator, we find three complete cycles of current direction associated with one cycle of the stator. By increasing the electrical phase angle between phases by a factor of three, the number of magnetic poles developed by the stator is increased by a factor of three. There are a number of symmetry factors that enter into the selection of allowable phase differentials. The phase angle differential must be an integral multiple of the base phase relation; otherwise a discontinuity will develop. Additionally, for machines which use windings, rather than single inductors in single slots (so called "half turn" windings), the phase angle differential must be an odd integral multiple of the base phase relation, otherwise the currents in opposite sides of the same winding would oppose each other. Finally, the nice pattern of monotonically increasing pole count with increasing phase angle breaks down if the phase angle between slots exceeds 180 degrees. For wound stator machines then, the allowable multiples of the base phase differential are all odd integers less than or equal to the number of slots in the base pole phase group. The example 30 slot 15 phase machine is thus capable of operating with 2, 6, 10, 14, 18, 22, 26, or 30 poles, through the expedient of operating with phase differentials of 24, 72, 120, 168, 216, 264, 312, or 360 degrees. Note that the last configuration is not possible for a symmetric star connected drive, since all phase terminations are in phase. However it is possible to use "full bridge" drive to both sides of each phase winding. Also, the 30-pole field is not a self-starting rotating field. As the pole count increases, the synchronous speed of the machine will decrease for a fixed drive frequency, as one expects with conventional 3-phase machines of differing pole count. This change in pole count has been verified experimentally. As mentioned, the direct value of pole changing is rather small. When pole count is increased, the pole area necessarily decreases, and greater net current is required to maintain the same total magnetic flux levels. The increase in drive frequency needed to get the same synchronous speed means greater hysteresis and eddy current losses. Nevertheless, there are several benefits caused by pole changing. Back iron saturation is reduced during operation at high flux levels. Additionally, at extremely low synchronous speeds, the higher drive frequencies associated with pole changing may increase the RMS current capabilities of the power electronics. By far the most important benefit of the pole changing capabilities is in the use of harmonic currents. Q - How would you best describe the harmonic phase relation? A - Periodic waveforms may be decomposed into a (possibly infinite) sum of sinusoids. These sinusoids must be described by both their frequency and their phase. Of particular interest are harmonics, sinusoids with frequencies that are integral multiples of some base, or fundamental frequency. The amplitudes and phases of harmonic components may be used to describe the shape of nonsinusoidal periodic functions, although often only the amplitudes are described. A common example is the square wave, which may be described by the following equation which is an infinite series: F(t) = .( sin(t) + 1/3sin(3t) + 1/5sin(5t) + 1/7sin(7t) + 1/9sin(9t) + .....) A square wave is composed of the fundamental plus all odd order harmonics, with an amplitude decreasing as the inverse of the harmonic order. Critical to the shape of the square wave is the fact that all the harmonic components at their respective zero phases at the same time that the fundamental is at its zero phase. If we alter this phase relation, then a rather different waveshape is produced. If we graph the equation F(t) = .( - 2/3sin(3t) - 2/5sin(5t) - 2/7sin(7t) - 2/9sin(9t) + .....), which has exactly the same harmonic amplitudes as the square wave but adds a 180 degree phase difference to the third harmonic, then a nearly triangular waveform is produced. The harmonics present in any waveform of fixed shape will always have precisely the same phase relation and amplitude. We now give consideration to the phase relation between harmonics of the same order, but feeding different windings of the electrical machine. The question is: if, for any two phases in a machine the fundamental of the drive waveforms have the appropriate phase relation to properly drive the machine, what is the phase relation of any harmonic n of the drive waveforms? In the case of a balanced drive, meaning that the same drive waveform with the same amplitude and frequency is fed to each stator phase, the only difference between the currents flowing into each stator phase is their timing. Since the waveshapes are the same, each harmonic of the drive waveforms has exactly the same time differential. Phase angle, however, is not measured in fixed time units such as seconds, but rather in relative units. A phase angle of 360 degrees corresponds to a time differential of one full cycle of the waveform of interest. For example, a 24- degree phase angle between two 15-millisecond period drive waveforms corresponds to a time differential of 1 millisecond. The time differential between all of the harmonics is also 1 millisecond. The third harmonic has a period of 5 milliseconds, meaning that for the third harmonic the phase difference is 72 degrees. The fifth harmonic has a period of 3 milliseconds, and the phase difference will be 120 degrees. This series continues; for each harmonic in a pair of drive waveforms of exactly the same waveshape and amplitude, but with different phase, the phase difference measured in terms of the harmonic is equal to the phase difference measured in terms of the fundamental times the order of the harmonic. Consider this in relation to the method of pole changing in the Chorus drive. Pole changing is obtained when the phase angle between adjacent phases is changed to an odd multiple of the minimum symmetry allowed phase angle. The odd harmonics present in the drive waveform have phase angle differences that are odd multiples of the fundamental phase angle. If drive waveforms with suitable fundamental phase angle relations are fed to the Chorus drive, then harmonics present in these drive waveforms will have suitable phase angle relations for pole changing. If the fundamental component of the drive waveform produces a two pole rotating field; then the third harmonic will produce a six pole rotating field, the fifth harmonic will produce a ten pole rotating field, and so on. This will continue on up to the highest pole count rotating field which the stator of winding is capable. At the same time, each harmonic component, in addition to having a phase angle difference, and thus a pole count equal to its harmonic order times the fundamental phase angle difference, has a frequency equal to its harmonic order times the fundamental frequency. The third harmonic produces a rotating field with three times the pole count of the fundamental, and excites it at a frequency of three times that of the fundamental. The net result is a rotating field that rotates at the same speed and direction as that of the fundamental. Similarly for the fifth harmonic, and all odd harmonics up to the point where the highest possible pole count is produced. The rotating fields produced by harmonics in the drive waveform are synchronous with that of the fundamental. Questions about the Company and its Strategy Q - Why are you based in Gibraltar? A - We have discovered that Gibraltar is an excellent place for a company to be domiciled. Gibraltar is a long time member of the European Union having English Common Law as the basis of commercial transactions. Gibraltar has superb infrastructure for conducing business world wide and is a very pleasant place to live, and it also offers a very comfortable, English-speaking environment. Gibraltar GAAP is the accounting standard, which is very similar to UK GAAP. Chorus Motors plc and the other companies in the Borealis Family conform and comply with all the rules and regulations of the Gibraltar Authorities. It should be noted that we no longer report to or are under the regulation of the Canadian Securities Authorities nor do we report to the US Security Regulators. Q - Why aren't you listed on the NASDAQ? A - We don't meet the technical qualifications for the NASDAQ exchange which require, among other things, that companies are large enough and have a minimum number of market makers. Also, under certain circumstances, foreign companies on the NASDAQ can be considered US companies, for tax and IP purposes. For these reasons many foreign companies prefer to trade OTC, including many well-known European companies. We review this policy from time to time, and we may well seek listings on other exchanges with the higher profile we would get from a licensing deal. Q - Your parent company Borealis has other technologies. How come? A - Our parent is now primarily a research and development firm. Company policy is to allow all staff -- even if they are not on the scientific side -- complete freedom to come up with bright ideas for new research. Most of these ideas turn out to be completely impractical. The few that have merit have been developed and patents filed. Those most advanced in development are spun off as separate companies, like Power Chips plc, so they are not tied to the success or failure of other ventures. Borealis shareholders still retain a majority interest, but new investors who are interested only in the one particular technology are able to invest just in that activity. Hence the structure of multiple companies under one parent. Q - What does the logo mean? A - The logo shows a beluga whale carrying a pickaxe. Our parent company was involved in minerals and exploration in Canada, and the logo was created back then, in the 1980s. The beluga whale is an Inuit symbol of good luck and prosperity, and the pickaxe represents prospecting for minerals. However, the whale is also a general symbol for environmental concern and the pickaxe can stand for basic industrial work. So the same corporate logo is applicable to both old and new endeavours. Copyright © 1995 - 2009 Chorus Motors plc. All rights reserved. Wheeltug and Chorus are Registered Trade Marks of Borealis Technical Limited Forward Looking Statement may be found at http://www.chorusmotors.gi/fwdlook.shtml. |