Yokogawa WT5000 Precision Power Analyzer

Overview

Between 16 to 18% of the total charge of an electric car is consumed by electric drive system losses. Electric and hybrid car manufacturers therefore need to accurately evaluate motor and inverter control in order to achieve higher precision and greater efficiency. Additionally, the accurate analysis of inverter waveforms without interference from switching noise is a key part of evaluating the motor drive circuit.

Key requirements:

• Multi-phase measurements from battery, inverter and motor
• Evaluation of motor characteristics such as torque, rotation speed and direction, slip and electrical angle
• Battery charging/discharging characteristics
• Harmonic analysis of inverter signals at various rotation speeds

The WT5000 Advantage

With high accuracy, multi-channel power measurements, evaluation of up to 4 motors and harmonic comparison capabilities, the WT5000 helps automotive engineers improve conversion efficiency, shorten charging times and improve driving range. 

Guaranteed accuracy in multichannel measurements 
It enables simultaneous measurements of voltage, current, power, torque, rotation speed, electrical angle and mechanical power.

Motor evaluation and mechatronic efficiency 
Measure rotation speed, torque, and output (mechanical power) of motors from analog/pulse inputs of rotation or torque sensors. A single WT5000 can be configured for synchronized measurements from up to 4 motors simultaneously.

Battery charging & discharging characteristics
Integration of Instantaneous positive and negative values of energy allows the evaluation of battery charging and discharging characteristics.

Harmonics Analysis & comparisons 
With the ability to measure harmonics up to the 500th order even at low rotation speeds, the WT5000 supports harmonic analysis without the need for an external sampling clock. 

Overview

Energy generated by photovoltaic cell modules and wind turbines is converted from DC to AC by a power conditioner. Minimizing losses in these conversions is key to improve the efficiency of the overall energy system.

Key requirements:

• Multi-phase measurements from boost converter, inverter and storage battery
• Evaluation of maximum power and instantaneous peak values
• Energy bought and sold in grid
• Battery charging/discharging characteristics
• Harmonic analysis of inverter signals at various generator speeds

The WT5000 Advantage

WT5000 helps engineers working in the development of renewable energy solutions, to improve conversion efficiency by offering precision insights in charging, discharging, storage and overall efficiency. 

Multi-channel Power measurements 
Evaluate Power conditioner efficiency with simultaneous measurements from the inputs and outputs of boost converter, inverter, and storage battery. With measurement capabilities from up to 7 input elements the WT5000 is ideal for voltage, current, power, and frequency (for AC) before and after each converter, as well as converter efficiency and charging efficiency. 

Instantaneous peak power 
In photovoltaic power generation, an Maximum Power Point Traker (MPPT) controller varies the voltage to maximize energy harvested from the solar panel. The WT5000 is capable of measuring not only the voltage, current, and power but also the voltage, current, and power peak values plus (+) and minus (−) sides, respectively 

Energy Bought/Sold and Charged/Discharged 
The WT5000E provides a current integration (q), apparent power integration (WS), reactive power integration (WQ), as well as effective power integration capable of integration in the power sold/bought and charge/discharge modes. 

Harmonics Analysis & comparisons 
Voltage fluctuations and harmonics flow into the power systems due to reverse power flow. The harmonic measurement function enables measurement of harmonic components to compute and display total harmonic distortion (THD) and harmonic distortion factor.

Overview

Motor drive technology has become more complex in recent years, pure sine-wave PWM is less common, and cases where the mean voltage differs greatly from the fundamental voltage waveform, are more frequent.

Key requirements:

• Multi-phase measurements from battery, inverter and motor
• Evaluation of motor characteristics such as torque, rotation speed and direction, slip and electrical angle
• Harmonic analysis of inverter signals at various rotational speeds

The WT5000 Advantage

With high accuracy, multi-channel power measurements, motor evaluation and harmonic comparison capabilities, the WT5000 helps engineers in motor and drive development to improve power consumption and conversion efficiency in inverter/motor drive systems. 

Guaranteed accuracy across a wide range 
 The WT5000 guarantees a basic power accuracy of ±0.03%, between 1% to 130% of the selected voltage and current measurement ranges, at 50/60 Hz. 

Simultaneous measurements from the inputs and outputs of boost converter, inverter, and storage battery 

Inverter and motor efficiency 
In addition to computing power conversion efficiency of inverter and motor (up to 7 power inputs), the WT5000, also allows the measurement of rotational speed, torque, and output (mechanical power) from the analog/pulse inputs of rotation or torque sensor. 

Harmonics Analysis & comparisons 
With the ability to measure harmonics up to the 500th order even at low rotation speeds the WT5000 supports harmonic analysis without the need of an external sampling clock. 

Overview

In transformer or reactor development, the WT5000 can be used to evaluate magnetic material characteristics using Epstein frame system.

Key requirements:

• High precision measurements of primary coil current and secondary coil voltage is needed.
• High accuracy in low power factor is needed.
• The magnetic flux density B and AC magnetic field H are key parameters to calculate iron loss.

The WT5000 Advantage

 Highest voltage and current accuracy
WT5000 provides highest power accuracy:
0.01% of reading + 0.02% of range (50/60 Hz)

High accuracy at low power factor
Effect of Power Factor of WT5000:
0.02% of S (0.5 A or more)
0.07% of S (200 mA or less)

Overview

For customers who use a large number of power meters, WT5000 can be used as a reference standard for periodic in-house calibration of power measurement instruments, such as the WT300E series and WT500. 

Key requirements:

• Sufficient power accuracy is needed for power measurement instruments.
• Power factor is adjustable, and the accuracy in low power factor is guaranteed.

The WT5000 Advantage

Highest power accuracy 
WT5000 provides highest power accuracy: 
0.01% of reading + 0.02% of range (50/60 Hz) 

High accuracy at low power factor 
Effect of Power Factor of WT5000: 
0.02% of S (0.5 A or more) 
0.07% of S (200 mA or less)