Mr. C at the Production Dept. asked project managers at the factory to provide him with an estimate of the typical production throughput on their production lines.

After analyzing the relevant data, Mr. C realized there was an issue on the production lines. The input voltage from wall sockets was very unreliable and had significant variations based on various factors like time of day, wiring impedance and load variations. Mr. C recalled that input voltage waveform of the refrigerator was too disturbed to collect the accurate data.

Lurking in the shadows of the operations is a condition known as poor voltage quality, a hidden cause that typically goes undetected. The voltage events can affect equipment performance in different ways.

Mr. C carefully analyzed the production process for bottlenecks to improve the throughput in manufacturing, and decided to improve the poor voltage quality. After searching for appropriate AC sources at the web site, Mr. C realized none of the AC source fitted his demands, it was too big to be installed in the production line.

Company W have been performing recruiting activities to attract talented candidates. Unfortunately, there’s been no progress on that since then. Candidates who are interested in our products and policy eventually decided to find other opportunities other than joining Company W. Mr. R at the R&D dept. wondered why this could happen, and reached a possible conclusion. Mr. R came up with test environment conflict that he experienced many times. Test environment conflict happens when more than one project needs to use same test instrument at the same time. It is a common cause of project delays and can be one of the main reasons why projects miss critical deadlines. Due to this, some engineers actually changed the job. Development department suffering from frequent test environment conflict gives engineers the same experience as being stuck in an airport during extreme delays. The occurrence of test environment conflicts can be reduced through the use of dedicated, persistent environments for individual projects. However, it would not be practical to install some large systems in their limited space.

Company T manufactures and supplies electric components for avionics market. The company had been facing a few problems about the AC power supplies to be used for the compliance test and endurance test. Electricity proves its potential in aviation industry. More Electric Aircraft (MEA) and All Electric Aircraft (AEA) are emerging and leading the way in the avionics industry. And the necessary power capacity of the power supply on board becomes high. The company had been trying to find the way to meet the trend.

Electrification of aircraft has been increasing in all aviation programs. The global MEA market has drastically grown because of the increase in global air traffic. The challenge in the global MEA market is the need for huge amounts of electric power for systems, with the current technologies in power electronics, it is difficult to achieve full efficiency. It had been a problem at the company to procure AC power supplies for their tests, since the top management showed reluctance to introduce the AC power supplies which the design and development department wanted. The top management carefully checked the budget request for unfixed projects. “They were concerned about the possibility that the AC power supplies would be covered with dust without using it after the introduction. If we introduced the AC power supplies with power capacity covering just current need, we knew that our test lab. will have lacked the power capacity in a few years. And buying additional power supplies as the need arises makes us spent more money”, said Mr. U at the Design and Development Dept.

What bothered Mr. U more was that he did not have enough space to install the big AC power supplies in their limited floor.

The company F manufactures electric components to be mounted in aircrafts. The company have been increasing effectiveness in quality control management to meet high safety performance. Quality Assurance Department who conducts verification test to comply with international standards plays an important role in the organizations. “To gain global market access for our products, we must comply with region or country specific directives and it has been becoming difficult every year”, said Mr. H, Director of the Quality Assurance Dept. at the company.

He also said, “We perform the strict compliance test and regulatory change is proceeding around the world, moreover the revisions of airframe base are made. Coping with the new regulatory requirements imposes a high degree of complexity upon our limited engineers. And the compliance test failures can be costly for a project team, time and money wise”, said Mr. H. These circumstances urged him to find the solution to increase the production efficiency with increasing engineer’s capability.

As a consequence of the electrification, it has been more challenging to ensure the appropriate compliance tests. Mr. H had dealt with the pressure to perform the test to meet the requirements. His team had a tight schedule, he should ensure that the team have a proper and a clear understanding of the standards, procedures and methodology to prevent lack of compliance. He had been urged to improve the situation before any problem occurs.

This case involves a company that supplies motors to a range of manufacturers. The company received a complaint from one of its customers about motor vibration. The head of the company’s design and development division explains:

“Our client told us to look into the issue of a motor we had supplied it with that was exhibiting vibration. The design and development division tried to find the cause on the case straight away.”

The team first tested the motor using an inverter power supply. However, the testing was more difficult than they expected.

“The output of pulse width modulation (PWM) inverters is characterized by a switching ripple current superimposed on the output waveform. Because the torque of the motor is also affected by ripple current from the inverter, we were unable to isolate the torque ripple attributable to the motor itself. This meant that our tests were unable to determine whether the problem was caused by the motor, the inverter, or the controller.”

As time ticked on with no solution in sight, the team became increasingly uneasy.

“If we didn’t identify the cause soon, we would be forced to shut down the motor manufacturing line. I was anxious and felt the need to identify the cause as soon as possible,” recalls the divisional head.

While QM Power moved premises with great expectations, an unreliable power supply made motor testing fraught with complications.

QM Power realized that the large power supply it had provided for testing purposes was unable to test its new motor properly. As things stood, QM Power had no prospect of performing precise or efficient testing.

The leader of the development team recalls─
“While we tried using mains power as an alternative, testing still didn’t go well. The unpredictable and noisy nature of the mains supply creates unexpected test results. After that, we tried using a variac to limit the voltage supplied to the device under test. However, this approach was not only time-consuming, but yielded spurious results, and tests sometimes had to be repeated. The variac also did not allow us to vary the frequency of the current supplied to the device under test. We would have liked to have had more flexibility when controlling frequency.”

When developing electric motors, it is ultimately necessary to control the voltage waveform applied to the motor being tested, to see how the motor will respond to unexpected conditions. QM Power needed to install a permanent, high-performance power solution in its new premises.

The development team began to research the problem in the hope of finding a relocatable, compact, high-output, power supply with variable frequency, that could perform both AC and DC testing.

Boosting Energy Efficiency is Easier Said than Done.

In this case study, our client had been actively trying to reduce their carbon dioxide emissions and established an even more aggressive emissions target. They were attempting to reduce the amount of power consumed by the factory where they manufactured their flagship product: air-conditioners. However, the factory in question was already implementing measures to reduce power consumption and was not readily able to make further cuts. The client therefore decided to focus on processes that had yet to be addressed by previous efficiency improvements. The manager of the client’s manufacturing division explains:

“When we performed another review of the various processes carried out in the factory, we found that a large amount of power was being consumed by elements under test, or EUTs. The main reason for the increased power consumption was that many power supplies and checking devices needed to be left on all the time to accommodate our irregular testing schedule. Also, because many different models of air-conditioners were tested at the factory, all of our power supplies needed to be on standby such that testing of the maximum capacity device could be performed at any time.”

In light of these findings, the manager asked the manufacturer of the power supply used at factory about energy saving features. However, he was informed that the power supplies lacked any such function.

“No other processes at the factory offered the potential for significant reductions in power consumption, so our only option was to make changes to the power supply for EUTs,” says the manager.

Asked repeatedly by management to come up with solutions, the manager was forced to find a solution as soon as possible.

Speeding up Analog Current Measurement and Sensor Adjustment.

The manufacturer in question receives a steady stream of requests to develop components for use in automotive applications that utilize hi-spec motors, including power steering and electric compressors. The design and development division always ran on a tight schedule and decided to improve this situation by making their testing process faster and more efficient. However, no matter how they tried, the team was unable to reduce the time taken by one particular process. A member of the design and development team explains:

“The issue was the process for outputting analog current readings for motors. While we normally used an inverter power supply when taking readings of high current motors, if a problem arose, we would replace the inverter power supply with a more precise AC power supply. In order to control the power supply output, we needed to take readings of current flow, and would attach an external current sensor to do so. Setting all this up was very time-consuming.”

Many of the motors were three-phase motors, which required three current sensors. Furthermore, when performing more involved tests, the team needed to connect power supplies and amplifiers as well.

“The complexity of the task and the limited number of personnel available meant the process was naturally time-consuming. We reviewed the process multiple times to try and improve things, but did not glean any insight into how we could make improvements,” says the employee.